taxonID	type	description	language	source
4E3F87EAF427FFA4F89BF9E7FA60DBB7.taxon	type_taxon	Type species. Ceratonereis mirabilis Kinberg, 1865, by subsequent designation (Hartman 1948).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF427FFA4F89BF9E7FA60DBB7.taxon	diagnosis	Diagnosis for atoke specimens (emended from Bakken & Wilson 2005, new features highlighted in boldface). Prostomium with anterior margin deeply incised. Two antennae subulate or lanceolate, two palps with cylindrical palps and rounded or pyriform palpostyles, four eyes, four pairs of anterior cirri with cirrostyles long and slender, present. Maxillary ring with conical paragnaths in areas II – IV, area I with or without paragnaths. Oral ring with papillae on areas VI, areas V and VII – VIII bare; areas VI-V-VI λ-shaped. Paired oesophageal caeca absent. Dorsal cirri with cirrophores and cirrostyles distinct. Dorsal ligules strongly reduced or absent in posterior chaetigers.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF421FFAEF89BFB51FC55DE80.taxon	description	Figures 3 – 4	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF421FFAEF89BFB51FC55DE80.taxon	materials_examined	Type material. Southwestern Atlantic Ocean, Brazil. Syntypes of Ceratonereis mirabilis SMNH 456 (2), 9 º S Brazil, 33 m, 1852, Coll. Werngren. Additional material. Southwestern Atlantic Ocean, Brazil. MNHN A 886 (1), R / V Calypso, Sta. 14, F. Noronha, baie Sta. Antonio, 6 – 10 m, plongée, roche, coraux, 18 November 1961. MNHN A 886 (1), R / V Calypso, Sta. 23 (8 ° 19 ’ S, 34 ° 39 ’ W), drague, algues, coraux, 75 m, 21 November 1961. MNHN A 886 (1), R / V Calypso, Sta. 31 (9 º 40 ’ S, 35 ° 18 ’ W), drague, algues, 54 – 47 m, 22 November 1961. MNHN A 886 (no specimen found), R / V Calypso, Sta. 10 (3 º 51.5 ’ S, 33 º 51.5 ’ W), drague, roches, coraux, algues, 17 November 1961.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF421FFAEF89BFB51FC55DE80.taxon	description	Description. Syntypes (SMNH 456) consists of four fragments in poor condition, very friable tissue, dissections were not attempted (Fig. 3 A); an anterior fragment 6 mm long, 0.8 mm wide at chaetiger 10 excluding parapodia, 29 chaetigers (Fig. 3 A, B), and its respective posterior end 6 mm long, 0.8 mm wide, 24 chaetigers (Fig. 3 A), used for number of paragnaths; another larger medium portion 5.8 mm long, 1 mm wide, 19 chaetigers, and a posterior end 4 mm long, 0.8 mm wide, 17 chaetigers. Additional material from Brazil (MNHN A 886) in good condition (Fig. 3 C – E); one specimen dried (Sta. 23) and in two fragments; one specimen (Sta. 14) incomplete, most anterior cirri detached, 9 mm long, 1 mm wide at chaetiger 10 excluding parapodia, 42 chaetigers, used for description of parapodia and chaetae; one specimen (Sta. 31) incomplete, in good condition, 5.5 mm long, 1.5 mm wide at chaetiger 10 excluding parapodia, 11 chaetigers. Body pale, without pigmentation, glandular masses not observed (Fig. 3 A – E). Prostomium as long as wide, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 3 A – E). Antennae lanceolate, 1.5 x long of prostomium, as long as or shorter than palps (Fig. 3 B – E). Eyes rounded, subequal, in trapezoidal arrangement (Fig. 3 A – E). Palpophores subcylindrical, longer than prostomium; tips of palpostyles rounded or pyriform (Fig. 3 A – E). Achaetous ring as long as chaetiger 1, anterior margin convex (Fig. 3 A, D). Tentacular cirri smooth, posterodorsal cirri extending backwards to chaetiger 15 (Fig. 3 B – E). Pharynx everted in one syntype, examined by dissection in non-type. Jaws amber, 7 teeth present along cutting edge (Fig. 4 H). Maxillary ring cylindrical, oral ring frustum-shaped, 2 – 3 x longer and 1.2 x wider than maxillary ring (Fig. 3 B). Maxillary ring: I = 0; IIa = 14 (14 – 15) and IIb = 16 (14 – 16) cones in arc; III = 11 (11 – 25) cones in ellipse; IVa = 12 (12 – 15) and IVb = 18 (15 – 18) cones in ellipse. Oral ring: V = 0; VIa-b = 1 rounded papilla; VII-VIII = 0. Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Dorsal cirri filiform, progressively relatively longer; 4.7 x longer than neuroacicular ligule in chaetiger 2, 5.7 x longer in chaetiger 7, 8 x longer in chaetiger 13, 10.3 x longer in chaetiger 23, 9.3 x longer in chaetiger 33 (Fig. 4 I – M). Dorsal ligule subulate or digitiform, progressively shorter toward posterior chaetigers; 1.3 x longer than neuroacicular ligule in chaetiger 7, 0.6 x length of neuroacicular ligule in chaetiger 13, 0.7 x length in chaetiger 23, 0.2 x length in chaetiger 33 (Fig. 4 I – M). Notopodial prechaetal lobe absent throughout (Fig. 4 I – M). Median ligule subconical, blunt tip; 1.4 x longer than neuroacicular ligule in chaetiger 7, 1.4 x longer in chaetiger 13, 1.3 x longer in chaetiger 23, as long as in chaetiger 33 (Fig. 4 I – M). Neuroacicular ligule subconical throughout, progressively relatively shorter toward posterior chaetigers (Fig. 4 I – M). Neuropodial superior and inferior lobes absent (Fig. 4 I – M). Neuropodial postchaetal lobe digitiform in anterior chaetigers, becoming lamelliform toward posterior chaetigers (Fig. 4 I – M). Ventral ligule digitiform throughout, longer than neuroacicular ligule in anterior chaetigers, becoming shorter than toward posterior chaetigers; 3.6 x longer than neuroacicular ligule in chaetiger 2, 1.2 x longer in chaetiger 7, 1.3 x longer in chaetiger 13, 0.6 x length of neuroacicular ligule in chaetiger 23, 0.6 x length in chaetiger 33 (Fig. 4 I – M). Ventral cirrus filiform, extending beyond tip of neuroacicular ligule in posterior chaetigers; 2.8 x longer than neuroacicular ligule in chaetiger 2, 2.6 x longer in chaetiger 7, 2.3 x longer in chaetiger 13, 2.4 x longer in chaetiger 22 (Fig. 4 I – M). Aciculae amber throughout. Notoaciculae present in first two chaetigers (Fig. 4 I). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 4 J – M). Notochaetae both short-bossed heterogomph spinigers and falcigers; spinigers in all chaetigers, pectinate, teeth minute, decreasing in size toward tip (Fig. 4 A); falcigers appearing from chaetigers 15 – 16, pectinate, teeth coarse, distal teeth not extending beyond blade tip, blade tip with a distal tooth, giving a bifid appearance (Fig. 4 B, C), occasionally two falcigers with distinct blade size at the same chaetiger (Fig. 4 C), shaft becoming slightly stouter toward posterior chaetigers (Fig. 4 B, C). Supracicular neurochaetae short-bossed heterogomph spinigers and long-bossed heterogomph falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, teeth minute, distal teeth occasionally barely extending beyond blade tip, blade tip rounded along first 15 – 16 chaetigers, with a very small distal tooth thereafter, often nearly rounded (Fig. 4 D, F), blades becoming shorter toward posterior chaetigers (Fig. 4 D, F). Infracicular neurochaetae both long-bossed heterogomph spinigers and falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, teeth minute, distal teeth barely extending beyond blade tip, blade tip rounded along first 15 – 16 chaetigers, with a very small distal tooth thereafter, often nearly rounded, blades becoming shorter toward posterior chaetigers (Fig. 4 E, G). Pygidium unknown.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF421FFAEF89BFB51FC55DE80.taxon	discussion	Remarks. Treadwell (1901) thought that Nereis gracilis Webster, 1884 was a junior synonym of Ceratonereis mirabilis (as Nereis mirabilis). Later, Hartman (1948) briefly redescribed C. mirabilis based on the type material and also concluded C. tentaculata, C. singularis, Nereis singularis Treadwell, 1943 (fide Hartman 1956), and Nereis gracilis (fide Hartman 1959) are junior synonyms of it. Perkins (1980) redescribed the species based on both type and non-type materials of several localities from the Caribbean Sea, recognized C. tentaculata as a valid species, and regarded Nereis gracilis Webster, 1884 as a junior synonym of it. After the examination of type and additional material from Brazil, C. mirabilis is restricted to Brazilian coasts, and the synonymy of N. gracilis is rejected and discussed in the remarks of the latter species. Synonymy of N. singularis with C. mirabilis and C. singularis is discussed in the remarks of the latter species. The specimens of C. mirabilis recorded by Santos & Lana (2003) from Rocas Atoll, Brazil, match well with the current description. Ceratonereis mirabilis has been recorded several times from the Caribbean Sea (Dean 2012). Perkins (1980) recorded C. mirabilis from Bermuda, Bahamas, Barbados, Florida, and Puerto Rico, but Bermudan specimens belong to C. gracilis and the remaining ones need to be re-assessed because likely they are C. nancyae n. sp.; records of C. mirabilis by Salazar-Vallejo & Jiménez-Cueto (1997) belong to C. nancyae n. sp. Ceratonereis mirabilis sensu Imajima (1972) differs from C. mirabilis in the following features: 1) in Japanese specimens, dorsal ligules are longer than median ligules in anterior chaetigers, whereas in Brazilian ones they are shorter; 2) in Japanese specimens, dorsal ligules are relatively larger in posterior chaetigers than in Brazilian specimens; 3) in Japanese specimens, dorsal cirri are relatively shorter than in Brazilian ones. Atoke specimens from the South China Sea recorded by Wu et al. (1985) are similar to Japanese ones, except the jaws have indistinct teeth along the cutting edge, dorsal cirri are relatively longer, and ventral cirri extend beyond ventral ligules in the first two chaetigers. The same author excluded the presence of lobes in areas VI in the description, but they were represented in the drawing of the pharynx (Imajima 1972, fig. 13 b). Fauvel (1939) recorded C. mirabilis from Vietnam after the presence of an anterior margin of prostomium deeply incised, long dorsal cirri and falcigers with long blades; also, he suggested specimens identified by Gravier & Dantan (1934) as Nereis (Ceratonereis) singularis, and their new species Nereis (Ceratonereis) incisa and Nereis (Ceratonereis) imperfecta, from Central Vietnam, are synonyms of C. mirabilis. Specimens used in those works were not studied here; re-evaluation of these specimens is needed to determine if they are C. mirabilis or C. singularis. Day (1967) recorded C. mirabilis from Mozambique and Madagascar, but their specimens differ from Brazilian ones as follows: 1) in African specimens, the dorsum is minutely papillated, whereas in Brazilian ones it is smooth; 2) in African specimens, dorsal cirri are relatively shorter throughout the body than in Brazilian ones; 3) in African specimens, ventral cirri are shorter than ventral ligules in posterior chaetigers, whereas in Brazilian ones they are longer; 4) in African specimens, median ligules are shorter than neuroacicular ligules, whereas in Brazilian ones they are longer. Records of C. mirabilis from the Persian Gulf (Fauvel 1911; 1918; 1919), the Australian (Hutchings & Turvey 1982), Egyptian (Abdelnaby 2020), Indian (Pati et al. 2014; Sekar et al. 2016), and Mediterranean coasts (Çinar 2005), and other regions, need to be addressed in future works.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42DFFA8F89BFCE4FB45DA1C.taxon	description	Figures 5 – 8	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42DFFA8F89BFCE4FB45DA1C.taxon	materials_examined	Type material. Northwestern Atlantic Ocean, Bermuda. Syntypes of Nereis gracilis USNM 4787 (2), Bermuda, 1876, Coll. G. B. Goode. Additional material. Northwestern Atlantic Ocean, Bermuda. USNM 1436352 (1), St. George’s Island, 6 – 9 m, 25 August 1960, Coll. T Tucker. USNM 1490819 (1), Bermuda, S side of Ferry Reach, about ½ way along Kindley Field Rd., 23 November 1976, narrow-bladed grass in mud substrate, Coll. ML Jones. USNM 1490818 (2), Bermuda, SW of Whalebone Bay, 17 November 1979, Coll. ML Jones. USNM 1490820 (1), Harrington Sound, Trunk Island, 12 August 1975, in rocks, Coll. ML Jones. AMNH 2405 (1), Castle Harbor Reef, Bermuda, 15 August 1931, Coll. Bermuda Oceanographic Expedition. AMNH 2504 (1), Castle Harbor Reef, Bermuda, 15 August 1931, Coll. Bermuda Oceanographic Expedition. AMNH 2538 (5 males), Bermuda, 18 August 1931, Coll. Bermuda Oceanographic Expedition. AMNH 556 (1 female), Bermuda, no date, Coll. A. E. Verrill and party.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42DFFA8F89BFCE4FB45DA1C.taxon	description	Description of atoke. Syntypes of Nereis gracilis (USNM 4787) consist of two anterior fragments in fair condition (Fig. 5 A); one anterior end with deep cuts along some chaetigers caused by previous dissections, 55 mm long, 1.2 mm wide at chaetiger 10 excluding parapodia, 30 chaetigers; another anterior end 76 mm long, 1.4 mm wide at chaetiger 10, 33 chaetigers. Specimen from Bermuda (USNM 1490819) complete, 14 mm long, 0.7 mm wide at chaetiger 10, 61 chaetigers. Two additional specimens from Bermuda (USNM 1490818) complete, one specimen used for description, 35 mm long, 1.1 mm wide at chaetiger 10, 73 chaetigers (Fig. 5 G). Non-type female (AMNH 556) incomplete, not transformed, 5.2 mm long, 1 mm wide at chaetiger 10, 21 chaetigers (Fig. 8 A); body filled with oocytes, parapodia as in atokes. Body pale or whitish, glandular masses not observed (Fig. 5 E – H). Prostomium 1.8 – 2.0 x wider than long, sub pentagonal, anterior margin deeply incised, dorsal groove present (Fig. 5 B, E, H). Antennae subulate, 1.5 x longer than prostomium, not extending beyond palps (Fig. 5 B, E, H). Palpophores subcylindrical, twice longer than prostomium; tips of palpostyles pyriform (Fig. 5 B, E, H). Eyes rounded, subequal, in trapezoidal arrangement, blackish, as wide as basal diameter of antennae, lenses not visible, posterior pair not covered by achaetous ring (Fig. 5 B, E, H). Achaetous ring as long as chaetiger 1, anterior margin convex (Fig. 5 B, E, H). Tentacular cirri smooth, posterodorsal cirri extending backwards to chaetigers 16 – 18 (Fig. 5 E, G, H). Pharynx not everted in syntypes, dissection avoided to prevent further damage, everted in non-type specimen (USNM 1490820) (Fig. 5 C – D). Jaws brown to dark brown (Figs 5 C – D, 6 A), 6 teeth extended along cutting edge (Fig. 6 A). Maxillary ring cylindrical, oral ring frustum-shaped, both ring with similar length and width (Fig. 5 C – D). Maxillary ring: I = 0; IIa = 6 (6 – 12) and IIb = 14 (7 – 14) cones in ellipse; III = 6 (6 – 10) cones in round; IVa = 10 (10 – 13) and IVb = 14 (10 – 14) cones in round (Fig. 5 C – D). Oral ring: V = 0; VIa-b = 1 slightly lamelliform papilla; VII – VIII = 0 (Fig. 5 C – D). Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Dorsal cirri filiform, progressively relatively longer; 3 x longer than neuroacicular ligule in chaetiger 2, 7 x longer in chaetiger 7, 4.2 x longer in chaetiger 13, 6 x longer in chaetiger 23, 9 x longer in chaetiger 42, 7.8 x longer in chaetiger 60, 20 x longer in chaetiger 71 (Fig. 6 B – H). Dorsal ligule subulate, progressively shorter and becoming digitiform toward posterior chaetigers, present throughout chaetigers; 2.3 x longer than neuroacicular ligule in chaetiger 7, 0.7 x length of neuroacicular ligule in chaetiger 13, 0.6 x length in chaetiger 23, 0.7 x length in chaetiger 42, 0.2 x length in chaetiger 60, 0.6 x length in chaetiger 71 (Figs 6 B – H, 7 A – C). Notopodial prechaetal lobe absent throughout (Figs 6 B – H, 7 A – C). Median ligule subconical or digitiform, progressively longer toward posterior chaetigers; 1.3 x longer than neuroacicular ligule in chaetiger 7, as long as in chaetiger 13, as long as in chaetiger 23, 1.5 x longer in chaetiger 42, 1.2 x longer in chaetiger 60, 1.6 x longer in chaetiger 71 (Figs 6 B – H, 7 A – C). Neuroacicular ligule subconical throughout, progressively relatively shorter toward posterior chaetigers. Neuropodial superior and inferior lobes absent (Figs 6 B – H, 7 A – C). Neuropodial postchaetal lobe digitiform in first two chaetigers, lamelliform and shorter than neuroacicular ligules thereafter, disappearing toward most posterior chaetigers (Figs 6 B – H, 7 A – C). Ventral ligule digitiform throughout, progressively shorter toward posterior chaetigers; 1.3 x longer than neuroacicular ligule in chaetiger 2, as long as in chaetiger 7, 0.7 x length of neuroacicular ligule in chaetiger 13, 0.5 x length in chaetiger 23, 0.5 x length in chaetiger 42, 0.4 x length in chaetiger 60, 0.7 x length in chaetiger 71 (Figs 6 B – H, 7 A – C). Ventral cirrus filiform, extending beyond tip of neuroacicular ligule in posteriormost chaetigers; twice longer than neuroacicular ligule in chaetiger 2, 1.6 x longer in chaetiger 7, 1.5 x longer in chaetiger 13, 1.5 x longer in chaetiger 23, 1.5 x longer in chaetiger 42, 1.7 x longer in chaetiger 60, 3.2 x longer in chaetiger 71 (Figs 6 B – H, 7 A – C). Aciculae amber throughout. Notoaciculae present in first two chaetigers (Figs 6 B, 7 A). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Figs 6 B – H, 7 A – C). Notochaetae both short-bossed heterogomph spinigers and falcigers; spinigers in all chaetigers, pectinate, teeth minute, decreasing in size toward tip; falcigers appearing from chaetigers 15 – 16, pectinate, teeth coarse, distal teeth barely extending beyond blade tip, blade tip with a distal tooth, giving a bifid appearance (Fig. 7 D – F), shaft becoming slightly stouter and blades longer toward posterior chaetigers (Fig. 7 D – F). Supracicular neurochaetae short-bossed heterogomph spinigers and long-bossed heterogomph falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, teeth minute, distal teeth barely extending beyond blade tip, blade tip rounded along first 15 – 17 chaetigers, with a distal tooth and bifid appearance thereafter, blades becoming wider toward posterior chaetigers (Fig. 7 G). Infracicular neurochaetae both long-bossed heterogomph spinigers and falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, teeth minute, distal teeth barely extending beyond blade tip, blade tip rounded along first 15 – 17 chaetigers, with a distal tooth and bifid appearance thereafter (Fig. 7 H – J), blades longer than supracicular falcigers in anterior chaetigers and becoming shorter toward posterior ones, blades becoming narrower toward posterior chaetigers, uppermost falcigers with longer blades than lowermost ones (Fig. 7 H – J). Pygidium funnel-shaped (Fig. 5 F); anal cirri filiform, as long as last 9 – 10 chaetigers (Fig. 5 F – G). Description of male epitoke. Non-type male (AMNH 2538) complete (Fig. 8 B), 12.7 mm long, 1 mm wide at chaetiger 10, 69 chaetigers, used for description. Body pale or yellowish, pigmentation absent (Fig. 8 A – B). Prostomium 1.2 x wider than long, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 8 B – C). Antennae lanceolate, as long as prostomium, not extending beyond palps (Fig. 8 B – C). Eyes rounded, subequal, in trapezoidal arrangement, blackish, 1.5 x wider than basal diameter of antennae, lenses visible, posterior pair not covered by achaetous ring (Fig. 8 B – C). Achaetous ring as long as chaetiger 1, anterior margin convex (Fig. 8 A – C). Tentacular cirri smooth (Fig. 8 A), posterodorsal cirri extending backwards to chaetiger 15. Pharynx dissected. Shape and size of both maxillary and oral rings difficult to interpret since the pharynx was not everted. Maxillary ring: I = 0; IIa = 8 (7 – 10) and IIb = 12 (10 – 12) cones in ellipse; III = 7 (7 – 8) cones in round, IVa = 11 (10 – 11) and IVb = 13 (13 – 15) cones in ellipse. Oral ring: V = 0; VIa-b = 1 slightly lamelliform papilla, VII-VIII = 0. Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Body divided into three regions: 1) pre-natatory region includes chaetigers 1 – 16 (15 – 16), 2) natatory region includes chaetigers 17 – 37 (36 – 37), 3) caudal region from chaetiger 38 (37 – 38) to end of body (Fig. 8 B). Pre-natatory region with parapodia resembling atokous ones (Fig. 8 E – F). Most dorsal cirri detached (Fig. 8 E – F). Dorsal ligule subconical, as long as neuroacicular ligule. Notopodial prechaetal lobe absent (Fig. 8 E – F). Median ligule subconical, as long as neuroacicular ligule (Fig. 8 E – F). Neuroacicular ligule subconical, progressively relatively longer toward middle chaetigers (Fig. 8 E – F). Neuropodial superior and inferior lobes absent (Fig. 8 E – F). Neuropodial postchaetal lobe digitiform in anterior chaetigers, lamelliform and shorter than neuroacicular ligule thereafter. Ventral ligule subconical, 1.2 x longer than neuroacicular ligule in first two chaetigers, as long as thereafter (Fig. 8 E – F). Ventral cirrus basally swollen and 1.8 x longer than neuroacicular ligule in first two chaetigers, filiform and 1.6 x longer thereafter (Fig. 8 E – F). Natatory region with most dorsal cirri detached (Fig. 8 G – H), crenulations absent. Dorsal ligule subconical, 0.3 x length of neuroacicular ligule throughout (Fig. 8 G – H). Notopodial prechaetal lobe rounded, lamelliform, 0.6 x length of neuroacicular ligule throughout (Fig. 8 G – H). Median ligule subconical, 1.3 x longer than neuroacicular ligule in anterior chaetigers, 1.2 x longer than thereafter (Fig. 8 G – H). Neuroacicular ligule subconical, mucronate, progressively relatively shorter toward posterior chaetigers, distally flattened (Fig. 8 G – H). Neuropodial inferior lobe digitiform, present in anterior chaetigers only (Fig. 8 G – H). Neuropodial postchaetal lobe transformed into flabelliform ventral lamella, half as long as neuroacicular ligule in anterior chaetigers, as long as toward posterior chaetigers (Fig. 8 G – H), reaching and fusing with ventral ligule (Fig. 8 H). Ventral ligule subconical and 0.3 x length of neuroacicular ligule in anterior chaetigers (Fig. 8 G), rounded and 0.2 x length toward posterior chaetigers (Fig. 8 H). Ventral cirrus filiform and 1.6 x longer than neuroacicular ligule in anterior chaetigers and 1.3 x longer toward posterior ones; upper and lower lamella appearing toward posterior chaetigers, upper one obovate and twice longer than rounded lower one. Caudal region with parapodia resembling atokous ones (Fig. 8 I – J). Most dorsal cirri detached (Fig. 8 I – J). Dorsal ligule subconical, blunt tip, progressively relatively longer toward posterior chaetigers; 0.3 x length of neuroacicular ligule in anterior chaetigers (Fig. 8 I), half as long as toward posterior chaetigers (Fig. 8 J). Medial ligule subconical, progressively relatively longer toward posterior chaetigers, as long as neuroacicular ligule in anterior chaetigers (Fig. 8 I), 1.7 x longer toward posterior chaetigers (Fig. 8 J). Neuroacicular ligule subconical, mucronate, progressively relatively shorter toward posterior chaetigers (Fig. 8 I – J). Ventral ligule digitiform in very first chaetigers, absent thereafter (Fig. 8 I – J). Ventral cirrus filiform, 1.2 x longer than neuroacicular ligule in anterior chaetigers (Fig. 8 I), 1.3 x longer toward posterior chaetigers (Fig. 8 J). Aciculae amber throughout. Notoaciculae present in first two chaetigers (Fig. 8 E). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 8 E – J). Both noto- and neurochaetae resembling atokous ones in pre-natatory region, replaced with paddle-like, shortbossed heterogomph chaetae in natatory region. Caudal region lacks chaetae excepting aciculae. Pygidium with four rounded lobes, each one with a small lamella; anal cirri absent (Fig. 8 D).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42DFFA8F89BFCE4FB45DA1C.taxon	discussion	Remarks. The syntypes of C. gracilis are in poor condition, most dorsal cirri are missing and the remaining ones are broken. Ceratonereis gracilis and C. mirabilis are very similar, especially in the short-bossed notopodial falcigers (usually used to separate species), so it is not surprising they were synonymized. Perkins (1980) redescribed C. mirabilis based on the Brazilian syntypes and the Bermudan syntypes of Nereis gracilis all in poor condition, and additional material from the Gulf of Mexico and the Caribbean Sea. Perkins (1980) noted differences between syntypes of C. mirabilis and N. gracilis, but they were considered “ of less importance ”. The differences in the number of paragnaths and the relative size of the chaetae were attributed to differences in size between the syntypes of both species, but how he reached that conclusion is unclear. The few specimens available for this study prevent this hypothesis from being tested, but in the specimens examined, the ranges largely overlap between both species, so here I focused on the differences in the parapodial characteristics. Regarding parapodia, Perkins (1980) stated that they are similar in both species and highlighted that N. gracilis also have ventral cirri reaching tips of ventral ligules in anterior chaetigers and are longer than all ligules in posterior chaetigers as it appeared in the original description by Webster (1884). The first feature is shared with the other two species studied by Perkins (1980), Ceratonereis tentaculata and C. singularis, whereas the second one is unique for C. mirabilis (doubtful in C. tentaculata); however, the author described and figured ventral cirri shorter than neuroacicular ligules for specimens from Gulf of Mexico and Florida (Perkins 1980, fig. 3 c, d). Based on the specimens examined here, C. gracilis and C. mirabilis share both features mentioned above, and only C. maya n. sp. has ventral cirri surpassing neuroacicular ligules in posterior chaetigers. Based on the both type and non-type material examined, C. gracilis differs from C. mirabilis in the following features: 1) in C. gracilis, dorsal cirri are 4.2 x longer than neuroacicular ligule in chaetiger 13, 6 x longer in chaetiger 23, whereas in C. mirabilis they are 8 x longer and 10.3 longer, respectively; 2) in C. gracilis, dorsal ligules of anterior chaetigers are as wide as median ligules, whereas in C. mirabilis they are narrower; 3) in C. gracilis, dorsal ligules of chaetigers 10 – 13 surpass the half of median ligules, whereas in C. mirabilis they are shorter; 4) in C. gracilis, ventral ligules of chaetigers 10 – 13 are 1.3 x longer than neuroacicular ligules, whereas in C. mirabilis they are 0.7 x the length of the neuroacicular ligules; 5) in C. gracilis, ventral cirri in chaetigers 20 – 23 does not surpass ventral ligules whereas in C. mirabilis they greatly surpass them; 6) in C. gracilis, the distal teeth of notopodial and neuropodial falcigers of middle and posterior chaetigers are longer and sharper than in C. mirabilis. Therefore, C. gracilis is regarded as a valid species and reinstated, with a distribution restricted to Bermuda.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42BFFB7F89BF958FD31DE54.taxon	description	Figures 9 – 10	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42BFFB7F89BF958FD31DE54.taxon	materials_examined	Type material. Northwestern Atlantic Ocean, United States. Holotype USNM 58740, Hutchinson Island, Sta. Lucie County, Florida (27 ° 19.1 ’ N 80 ° 13.2 ’ W), 8.2 m depth, 12 December 1976, Coll. N Whiting. Additional material. Northwestern Atlantic Ocean, United States. USNM 1490821 (5), S side of Tavernier Key, Florida Keys, Florida, July 1960, Coll. ML Jones. USNM 1490822 (1), Sta. 3 A, Key Largo, Florida Keys, Florida, 19 November 1968, Coll. ME Rice. Caribbean Sea, Mexico. ECOSUR P 3189 (2), Puente Las Coloradas, Yucatán (21 ° 35 ’ 36.82 ” N 88 ° 3 ’ 21.75 ” W), on dark greenish sponges, in mangrove roots, 13 May 2009, Col. S. I. Salazar-Vallejo, L. F. Carrera-Parra. ECOSUR P 3190 (1), Puente Las Coloradas, Yucatán (21 ° 35 ’ 36.82 ” N 88 ° 3 ’ 21.75 ” W), on algae in piles, 15 October, 2009, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. ECOSUR P 1111 (3), Laguna Nichupté, Quintana Roo (21 ° 06 ’ 11.6 ” N 86 ° 47 ’ 21.1 ” W), 5 July 1988, Coll. S. Jiménez-Cueto. ECOSUR P 1149 (2), Laguna Nichupté, Quintana Roo (21 ° 05 ’ 11.5 ’’ N 86 ° 47 ’ 21 ’’ W), 30 October 1987, Coll. M. S. Jiménez- Cueto. ECOSUR P 1155 (1), R / V Edwin Link, Sta. 2783 (18 ° 42 ’ N 87 ° 41 ’ W) Mahahual, Quintana Roo, 58.8 m depth, 24 August 1990. ECOSUR P 1159 (2), Mahahual, Quintana Roo (18 ° 43 ’ 1 ’’ N 87 ° 42 ’ 23 ’’ W), 1 October 1996, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. ECOSUR P 1161 (2), R / V Edwin Link, Sta. 2788 (18 ° 51.74 ’ N 87 ° 37.38 ’ W) Punta Changuay, Quintana Roo, 52.7 m depth, 26 August 1990. ECOSUR P 1162 (2), Laguna Nichupté, Quintana Roo (21 ° 06 ’ 11.6 ” N 86 ° 47 ’ 21.1 ” W), 30 October 1987, Coll. M. S Jiménez-Cueto. ECOSUR P 1163 (3), Laguna Nichupté, Quintana Roo (21 ° 05 ’ 11.5 ’’ N 86 ° 47 ’ 21 ’’ W), 30 October 1987, Coll. M. S. Jiménez- Cueto. ECOSUR P 1164 (1) Laguna Nichupté, Quintana Roo (21 ° 06 ’ 11.6 ” N 86 ° 47 ’ 21.1 ” W), 19 April 1988, Coll. M. S. Jiménez-Cueto. ECOSUR P 1165 (2), Laguna Nichupté, Quintana Roo (21 ° 05 ’ 11.5 ’’ N 86 ° 47 ’ 21 ’’ W), 30 October 1987, Coll. M. S. Jiménez-Cueto. ECOSUR P 1205 (1), Laguna Nichupté, Quintana Roo (21 ° 05 ’ 11.5 ’’ N 86 ° 47 ’ 21 ’’ W), 28 October 1987, Coll. M. S. Jiménez-Cueto. ECOSUR P 1207 (4), Playa Aventuras, Quintana Roo (20 ° 29 ’ 50 ” N 87 ° 13 ’ 53 ” W), 18 May 1986, Coll. S. I. Salazar-Vallejo. ECOSUR P 1217 (17), Punta Nizuc, Quintana Roo (21 ° 02 ’ 5.51 ” N 86 ° 47 ’ 43.02 ” W), 4 m depth, 1 September 1997, Coll. L. F. Carrera-Parra, S. I. Salazar-Vallejo, M. A. Ruiz-Zárate. Jamaica. UMML 22.1148 (2), R / V Pillsbury, Cruise 7006, Sta. 1252 (17 ° 09 ’ N 78 ° 57 ’ W), W Pedro Bank, Jamaica, 26 m depth, 14 July 1970.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42BFFB7F89BF958FD31DE54.taxon	description	Description. Atoke holotype (USNM 58740) complete, in two fragments, 20 mm long, 0.7 mm wide at chaetiger 10, 59 chaetigers (Fig. 9 B). Non-type specimen (ECOSUR P 1164) from Laguna Nichupté, Mexico, used for description to avoid further destruction of type material, in good incomplete, 14 mm long, 0.9 mm wide at chaetiger 10 excluding parapodia, 54 chaetigers. Another specimen (ECOSUR P 3190) from Las Coloradas, Mexico, used to show pharynx (Fig. 9 E – F), 26 mm long, 1.2 mm wide, 58 chaetigers. Non-type specimens most incomplete with tentacular and dorsal cirri missing. Body pale whitish or pale, glandular masses or pigmentation not observed (Fig. 9 A – D). Prostomium as long as wide, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 9 A, D). Antennae subulate, as long as prostomium, as long as palps (Fig. 9 A, D). Palpophores subcylindrical, as long as prostomium; tips of palpostyles rounded or pyriform (Fig. 9 F). Eyes rounded, subequal, in trapezoidal arrangement, blackish, as wide as basal diameter of antennae, lenses not visible, posterior pair not covered by achaetous ring (Fig. 9 A, D). Achaetous ring shorter than chaetiger 1, anterior margin convex (Fig. 9 A, D). Tentacular cirri smooth, posterodorsal cirri extending backwards to chaetigers 14 – 15 (Fig. 9 A, B, D). Pharynx examined by dissection in holotype, everted in non-type specimen. Jaws amber, 8 teeth (2 ensheathed) restricted to first two-thirds of cutting edge (Fig. 10 I). Maxillary ring cylindrical, oral ring frustum-shaped, 3 – 4 x longer and 1.2 x wider than maxillary ring (Fig. 9 E, F). Maxillary ring: I = 0; IIa = 8 and IIb = 9 cones in arc; III = 9 cones in round; IVa = 14 and IVb = 18 cones in ellipse. Oral ring: V = 0; VIa-b = 1 rounded papilla (Fig. 9 E, F); VII – VIII = 0. Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Dorsal cirri filiform, progressively relatively longer; 3.5 x longer than neuroacicular ligule in chaetiger 3, 7 x longer in chaetiger 10, 6 x longer in chaetiger 17, 6 x longer in chaetiger 19, 7.3 x longer in chaetiger 28, 10 x longer in chaetiger 53, 6.4 x longer in chaetiger 65 (Fig. 10 A – H). Dorsal ligule subulate, progressively shorter and becoming digitiform toward middle chaetigers, absent from chaetiger 20; 1.8 x longer than neuroacicular ligule in chaetiger 3, 1.5 x longer in chaetiger 10, 0.9 x length of neuroacicular ligule in chaetiger 17, 0.2 x length in chaetiger 19 (Fig. 10 A – H). Notopodial prechaetal lobe absent throughout (Fig. 10 A – H). Median ligule subconical or digitiform, progressively shorter toward posterior chaetigers; 1.4 x longer than neuroacicular ligule in chaetiger 3, 1.1 x longer in chaetiger 10, 0.8 x length of neuroacicular ligule in chaetiger 17, 0.8 x length in chaetiger 19, 0.9 x length in chaetiger 28, 0.6 x length in chaetiger 65 (Fig. 10 A – H). Neuroacicular ligule subconical throughout, progressively relatively longer toward posterior chaetigers. Neuropodial superior and inferior lobes absent (Fig. 10 A – H). Neuropodial postchaetal lobe lamelliform and shorter than neuroacicular ligules throughout, disappearing toward most posterior chaetigers (Fig. 10 A – H). Ventral ligule digitiform throughout, progressively shorter toward posterior chaetigers; 1.7 x longer than neuroacicular ligule in chaetiger 2, 1.2 x in chaetiger 3, 0.8 x length of neuroacicular ligule in chaetiger 10, 0.7 x length in chaetiger 17, 0.6 x length in chaetiger 19, 0.3 x length in chaetiger 28, 0.3 x length in chaetiger 53, 0.2 x length in chaetiger 65 (Fig. 10 A – H). Ventral cirrus filiform, not extending beyond tip of neuroacicular ligule; 2.2 x longer than neuroacicular ligule in chaetiger 2, 2 x longer in chaetiger 3, 1.6 x longer in chaetiger 10, 1.5 x longer in chaetiger 17, 1.2 x longer in chaetiger 19, 1.5 x longer in chaetiger 28, 1.1 x longer in chaetiger 53, 1.5 x longer in chaetiger 65 (Fig. 10 A – H). Aciculae amber throughout. Notoaciculae present in first two chaetigers (Fig. 10 A). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 10 A – H). Notochaetae both short-bossed heterogomph spinigers and falcigers; spinigers in all chaetigers, pectinate, teeth minute, decreasing in size toward tip; falcigers appearing from chaetigers 15 – 17, pectinate, teeth coarse, distal teeth barely extending beyond blade tip, blade tip with a distal tooth, giving a bifid appearance (Fig. 10 J), shaft becoming slightly stouter toward posterior chaetigers (Fig. 10 E – H). Supracicular neurochaetae short-bossed heterogomph spinigers and long-bossed heterogomph falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, teeth minute, distal teeth barely extending beyond blade tip, blade tip rounded along first 17 – 20 chaetigers (Fig. 10 K), with a distal tooth and bifid appearance thereafter. Infracicular neurochaetae both long-bossed heterogomph spinigers and falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, teeth minute, distal teeth barely extending beyond blade tip, blade tip rounded along first 17 – 20 chaetigers, with a distal tooth and bifid appearance thereafter (Fig. 10 L), blades longer than supracicular ones in anterior chaetigers, becoming shorter toward posterior ones. Pygidium tripartite; anal cirri filiform, as long as last 10 segments (Fig. 9 C).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42BFFB7F89BF958FD31DE54.taxon	discussion	Remarks. The original description is d and the attributes therein described match well with the type material examined. However, some features were not illustrated or described, including parapodia from the first two chaetigers, the pharynx including jaws, and posterior end. To improve the original description, and to show the current state of type material, a brief description including figures was made. The species is easily recognizable by the combination of attributes of disappearance of dorsal ligules from middle chaetigers and the presence of falcigers with distal teeth (i. e., bidentate) in noto- and neuropodial fascicles. Salazar-Vallejo & Jiménez-Cueto (1997: 363) described an inverted occurrence of falcigers having and lacking distal teeth in specimens of Laguna Nichupté (bidentate falcigers in first anterior chaetigers, becoming unidentate toward posterior ones), but after the examination of the specimens, the arrangement is as in holotype of C. longicirrata.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF42BFFB7F89BF958FD31DE54.taxon	distribution	Distribution. Florida, U. S. A.; Caribbean Sea.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF437FFB0F89BFF6CFDECDD0C.taxon	description	Figures 11 – 12	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF437FFB0F89BFF6CFDECDD0C.taxon	materials_examined	Type material. Caribbean Sea, Mexico. Holotype ECOSUR 0245, Contoy Island, Quintana Roo (21 ° 31 ’ 44.28 ” N 86 ° 48 ’ 11.53 ” W), 1.5 m depth, 1 March 2001, Coll S. I. Salazar-Vallejo, L. F. Carrera-Parra. Paratypes ECOSUR 0246 (2), Contoy Island, Quintana Roo (21 ° 31 ’ 44.28 ” N 86 ° 48 ’ 11.53 ” W), 1.5 m depth, 1 March 2001, Coll S. I. Salazar-Vallejo, L. F. Carrera-Parra. Paratype ECOSUR 0247 (1), Cabo Catoche, Quintana Roo (21 ° 36 ’ 32.06 ’’ N 87 ° 06 ’ 52.64 ’’ W), 2.5 m depth, 10 May 2009, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. Additional material. Gulf of Mexico, Mexico. ECOSUR 1120 (1), Laguna de Términos, Campeche, 27 July 1984, Coll. E. Escobar. Caribbean Sea, Mexico. ECOSUR P 1150 (4), Laguna Yalahau, Quintana Roo (21 ° 30 ’ N 87 ° 15 ’ W), 8 September 1993, Coll. S. I. Salazar-Vallejo. ECOSUR P 1157 (1), Punta Gorda, Quintana Roo (19 ° 47 ’ 51.03 ” N 87 ° 32 ’ 49.70 ” W), 27 August 1984, Coll. E. Escobar. ECOSUR P 1158 (1), Laguna Nichupté, Quintana Roo (21 ° 06 ’ 11.6 ” N 86 ° 47 ’ 21.1 ” W), 3 February 1988, in seagrasses, Coll. M. S. Jiménez-Cueto. ECOSUR P 1167 (2), Laguna Nichupté, Quintana Roo (21 ° 06 ’ 11.6 ” N 86 ° 47 ’ 21.1 ” W), 30 October 1987, Coll. M. S. Jiménez- Cueto. ECOSUR P 1197 (2), Laguna Nichupté, Quintana Roo (21 ° 06 ’ 11.6 ” N 86 ° 47 ’ 21.1 ” W), 5 July 1988, Coll. M. S. Jiménez-Cueto. ECOSUR P 1199 (1), Ría Lagartos, Yucatán (31 º 35 ’ 55.25 ” N, 88 º 9 ’ 23.9 ” W), 18 February 1999, Coll. S. I. Salazar-Vallejo, J. R. Bastida-Zavala. ECOSUR P 1200 (1), R / V Edwin Link, Sta. 2774 (18 ° 45.63 ’ N 87 ° 15.84 ’ W), Cayo Norte, Banco Chinchorro, Quintana Roo, 20 August 1990, Coll. E. Escobar, L. Soto. ECOSUR P 1201 (1), Punta Gavilán, Quintana Roo, 25 August 1990, Coll. E. Escobar, L. Soto. ECOSUR 1202 (3 males), Punta Gavilán, Quintana Roo, 25 August 1990, Coll. E. Escobar, L. Soto. ECOSUR P 1203 (1), Punta allen, Quintana Roo (19 º 47 ’ 58 ” N, 87 º 28 ’ 29 ” W), 2 June 1986, Coll. F. E. Donath. ECOSUR P 1206 (1), Punta Hualastok, Bahía de la Ascensión, Quintana Roo, 28 April 1987, Coll. M. S. Jiménez-Cueto. ECOSUR P 1208 (2), Laguna de Términos, Campeche (18 ° 39 ’ 7.29 ” N 91 ° 32 ’ 25.22 ” W), 27 July 1984, Coll. E. Escobar. ECOSUR P 1220 (1), Buenavista, Quintana Roo (18 ° 30 ’ 42 ’’ N 87 ° 45 ’ 30 ” W), 27 September 1996, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. ECOSUR P 3191 (1), Camping Beach, Contoy Island, Quintana Roo (21 ° 28 ’ 28.9 ” N, 86 ° 47 ’ 22.5 ” W), on seashell, 26 February 2008. ECOSUR P 3192 (1), Puerto Viejo, Contoy Island (21 ° 29 ’ 19 ” N, 86 ° 47 ’ 44 ” W), on mangrove roots, 24 February 2008. ECOSUR P 3193 (2), Contoy Island, Quintana Roo, Mexico, 1 March 2001. Jamaica. UMML 22.1163 (1), R / V Pillsbury, Cruise 7006, Sta. 1258 (17 ° 03 ’ N 78 ° 10 ’ W), Pedro Banks, Jamaica, 15 m depth, 15 July 1970. Nicaragua. UMML 22.1164 (1), R / V Pillsbury, Cruise 7101, Sta. 1330 (11 ° 51 ’ N 83 ° 27 ’ W), SE Nicaragua, 24 m depth, 28 January 1971. Venezuela. USNM 47771 (1), Cumaná Key, Mochima, 12 m depth, 21 October 1971, Coll. Edwards. USNM 49709 (1), La Gabarra Beach, Mochima Bay, 8 m depth, 11 May 1971, Coll. R. Edwards. British Virgin Islands. LACM-AHF 7370 (2) White Bay, Guana Island (18 ° 28 ’ 32 ” N, 64 ° 34 ’ 39 ” W), on artificial reef matrix structures (ARMs), 1.5 m depth, 9 July 2000, Coll. T. Zimmerman, G. Hendler, R. Ware, K. Fitzhugh. Type locality. Contoy Island, Quintana Roo, Mexico, at 1.5 m depth (Fig. 1).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF437FFB0F89BFF6CFDECDD0C.taxon	etymology	Etymology. The specific term maya is a noun in apposition. ‘ Mayan people’ is a collective term commonly used to refer indigenous peoples living mainly in southeast Mexico, Guatemala, Belize, Honduras, and El Salvador.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF437FFB0F89BFF6CFDECDD0C.taxon	description	Description. Holotype (ECOSUR 0245) is a complete atoke female, in excellent condition (Fig. 11 A – B, D – F), 240 mm long, 2.6 mm wide at chaetiger 10 excluding parapodia, 130 chaetigers, with oocytes present. Paratype (ECOSUR 0247) complete and in good condition (Fig. 11 C), 56 mm long, 1.5 mm wide at chaetiger 10 excluding parapodia, 65 chaetigers. Body pale or yellowish, tapering (Fig. 11 A – F); with brown pigmentation in paratype (Fig. 11 C), prostomium with spots in the incision of anterior margin, two spots over the eyes, and a cordiform spot between posterior pair of eyes, achaetous ring and anterior segments with two transverse narrow bands, giving it a striate appearance, pigmentation progressively faded out toward posterior end. Prostomium 1.5 x wider than long, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 11 A, C – D). Antennae lanceolate, 1.3 x longer than prostomium, not extending slight beyond palps (Fig. 11 A, C – D). Eyes rounded, subequal, in trapezoidal arrangement, blackish, as wide as basal diameter of antennae, lenses not visible, anterior pair sometimes reniform, posterior pair not covered by achaetous ring (Fig. 11 A, C – D). Achaetous ring twice longer than chaetiger 1, anterior margin convex (Fig. 11 A, C – D). Tentacular cirri smooth, posterodorsal cirri extending backwards to chaetiger 16 (Fig. 11 A, C – D). Pharynx everted in holotype (Fig. 11 A, E – F). Jaws brown with 8 teeth along cutting edge (Fig. 12 H). Maxillary ring cylindrical, oral ring frustum-shaped, 1.6 x longer and 1.4 x wider than maxillary ring (Fig. 11 E – F). Maxillary ring: I = 0; IIa = 8 and IIb = 7 cones in arc; III = 8 cones in round; IVa = 9 and IVb = 10 cones in round (Fig. 11 E – F). Oral ring: V = 0; VIa-b = 1 rounded papilla; VII-VIII = 0 (Fig. 11 E – F). Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Dorsal cirri filiform, progressively relatively longer; 3.2 x longer than neuroacicular ligule in chaetiger 1, 5.5 x longer in chaetiger 12, 9 x longer in chaetiger 30, 6.8 x longer in chaetiger 81, 10.4 x longer in chaetiger 121 (Fig. 12 A – F). Dorsal ligule subconical or digitiform, progressively shorter toward posterior chaetigers, present throughout; 1.4 x longer than neuroacicular ligule in chaetiger 12, 1.2 x longer in chaetiger 30, 0.2 x length of neuroacicular ligule in chaetiger 81, strongly reduced from chaetiger 121 (Fig. 12 A – E); posterior chaetigers in paratype with dorsal ligules throughout, 0.3 x length in chaetiger 52, 0.6 x length in chaetiger 65 (Fig. 12 F – G). Notopodial prechaetal lobe absent throughout. Median ligule subconical; 1.5 x longer in chaetiger 12, 1.8 x longer in chaetiger 30, 0.7 x length of neuroacicular ligule in chaetiger 81, 0.8 x length in chaetiger 121 (Fig. 12 A – G). Neuroacicular ligule subconical throughout, mucronate in middle and posterior chaetigers, progressively relatively longer and wider toward posterior chaetigers (Fig. 12 A – G). Neuropodial superior and inferior lobes absent (Fig. 12 A – G). Neuropodial postchaetal lobe digitiform in first two chaetigers, lamelliform and shorter than neuroacicular ligules thereafter, disappearing toward most posterior chaetigers (Fig. 12 A – G). Ventral ligule digitiform throughout, progressively shorter toward posterior chaetigers; 1.3 x longer than neuroacicular ligule in chaetiger 1, as long as in chaetiger 12, 0.6 x length of neuroacicular ligule in chaetiger 30, 0.2 x length in chaetiger 81, 0.3 x length in chaetiger 121 (Fig. 12 A – G). Ventral cirrus filiform, extending beyond tip of neuroacicular ligule in posteriormost chaetigers; 1.6 x longer than neuroacicular ligule in chaetiger 1, 1.7 x longer in chaetigers 12 and 30, 1.2 x length in chaetiger 81, 2 x length in chaetiger 121 (Fig. 12 A – G). Aciculae amber throughout. Notoaciculae present in first two chaetigers (Fig. 12 A). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 12 A – G). Notochaetae both short-bossed heterogomph spinigers and falcigers; spinigers in all chaetigers, pectinate, teeth minute, decreasing in size toward tip (Fig. 12 K); falcigers appearing from chaetigers 15 – 17, pectinate, basal teeth minute and greatly increasing in size toward distal blade, distal teeth not extending beyond blade tip in middle chaetigers and extending beyond toward posterior ones (Fig. 12 I – J), blade tip rounded throughout, shaft becoming slightly stouter toward posterior chaetigers (Fig. 12 I – J). Supracicular neurochaetae short-bossed heterogomph spinigers and long-bossed heterogomph falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, increasing in size toward distal blade, distal teeth extending beyond blade tip, blade tip rounded throughout, blades becoming wider toward posterior chaetigers (Fig. 12 M). Infracicular neurochaetae both long-bossed heterogomph spinigers and falcigers; spinigers with blades pectinate, basal teeth coarse and greatly decreasing in size and becoming minute toward distal blade (Fig. 12 N); falcigers pectinate, basal teeth minute and greatly increasing in size toward distal blade (Fig. 12 L, O), distal teeth extending beyond blade tip, blade tip rounded throughout (Fig. 12 L, O), blades shorter than supracicular falcigers in anterior chaetigers and becoming longer toward posterior ones, uppermost falcigers with longer and narrower blades than lowermost ones (Fig. 12 L). Pygidium swollen, funnel-shaped; anal cirri missing (Fig. 11 B).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF437FFB0F89BFF6CFDECDD0C.taxon	discussion	Remarks. The holotype is the largest specimen, being several times larger than the remaining material and more than 100 chaetigers. Of the specimens examined, only the holotype (last 5 chaetigers) and one paratype (ECOSUR P 1150) (last 2 chaetigers) have inconspicuous dorsal ligules in posterior-most chaetigers. In the first instance, the inconspicuous dorsal ligules in a few posterior-most chaetigers were attributed to the size and number of chaetigers in the holotype. This situation is similar to that found in Ceratonereis australis Hartmann-Schröder, 1985 having inconspicuous dorsal ligules in few posterior-most chaetigers and the number of chaetigers of the holotype is 100 chaetigers or greater (Hartmann-Schröder 1985). However, the finding of a complete small specimen demonstrated the presence of very reduced dorsal ligules, so the size was discarded for this species as a factor for this feature. Perkins (1980) studied some specimens from Venezuela, finding a high resemblance to C. singularis; however, the condition and number of species prevented an adequate description for a new species, naming it as Ceratonereis sp. Specimens studied by him, and deposited in USNM, were examined and are identical to those collected in the Mexican Caribbean. Hartmann-Schröder (1985) proposed the new subspecies Ceratonereis (Ceratonereis) singularis singularis for the form identified by Perkins as Ceratonereis sp. Type and additional materials of C. singularis from Western Mexico were examined to study if they belong to the same species, and they demonstrate to be distinct, and a new name for the new species C. maya n. sp. is proposed to avoid homonymy with C. singularis Treadwell, 1929 when elevated to the species level. There are several differences between C. singularis and C. maya n. sp. allowing their clear separation: 1) in C. maya n. sp., dorsal cirri are relatively longer throughout body than in C. singularis; 2) in C. maya n. sp., the dorsal ligules are much narrower than neuroacicular ligules in middle chaetigers, whereas in C. singularis they have similar wide; 3) in C. maya n. sp., both dorsal and ventral ligules reduce greatly their size toward posterior chaetigers, becoming papillae-like in posterior-most chaetigers and even inconspicuous, whereas in C. singularis they are relatively larger in posterior chaetigers; 4) the blades of notopodial short-bossed heterogomph falcigers in C. maya n. sp. are subequal in the same fascicle, whereas in C. singularis they can have different lengths; 5) pygidium in C. maya n. sp. is funnel-shaped, whereas in C. singularis it is tripartite and minute.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF437FFB0F89BFF6CFDECDD0C.taxon	distribution	Distribution. Caribbean Sea.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF433FFBBF89BFE68FDECDD0C.taxon	description	Figures 2 B, D; 13 – 16	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF433FFBBF89BFE68FDECDD0C.taxon	materials_examined	Type material. Caribbean Sea, Mexico. Holotype ECOSUR 0248, Buenavista, Quintana Roo (18 ° 30 ’ 42 ’’ N 87 ° 45 ’ 30 ” W), 1 m depth, 27 September 1996, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. Paratype ECOSUR 0249, Punta Allen, Quintana Roo (19 ° 47 ’ 58 ’’ N 87 ° 28 ’ 29 ’’ W), 11 June 1986, Coll. F. E. Donath. Additional material. Northwestern Atlantic Ocean, Bahamas. ECOSUR P 3110 (1), R / V Pillsbury, Cruise 7106, Sta. 1431 (21 ° 41 ’ N 73 ° 51 ’ W), Hogsty Reef, Bahamas, 27 m depth, 22 July 1971. Gulf of Mexico, Mexico. ECOSUR P 1204 (2), Sabancuy, Campeche (19 ° 10 ’ N 91 ° 39.9 ’ W), 28 August 1984, Coll. E. Escobar. Caribbean Sea, Mexico. ECOSUR P 1118 (14), Buenavista, Quintana Roo (18 ° 30 ’ 42 ’’ N 87 ° 45 ’ 30 ” W), 1 m depth, 27 September 1996, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. ECOSUR P 1151 (7), Xahuayxol, Quintana Roo (18 ° 33 ’ 30 ” N 87 ° 44 ’ 02 ” W), 27 September 1996, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. ECOSUR P 1152 (6 males), R / V Edwin Link, Sta. 2774 (18 ° 45.63 ’ N 87 ° 15.84 ’ W), Banco Chinchorro, Quintana Roo, 51.8 m depth, 20 August 1990. ECOSUR P 1153 (5), Punta Herradura, Quintana Roo (18 ° 34 ’ 59.61 ” N 87 ° 44 ’ 14.50 ” W), 28 September 1996, Coll. S. I. Salazar-Vallejo, L. F. Carrera-Parra. ECOSUR P 1154 (4 males), R / V Edwin Link, Sta. 2782 (18 ° 34.41 ’ N 87 ° 26.81 ’ W), Banco Chinchorro, Quintana Roo, 274.3 m depth, 23 August 1990. ECOSUR P 1156 (2 males), R / V Edwin Link, Sta. 2775 (18 ° 45.46 ’ N 87 ° 15.75 ’ W), Chichorro Bank, Quintana Roo, 86 m depth, 20 August 1990. ECOSUR P 1160 (1), R / V Edwin Link, Sta. 2777 (18 ° 26.02 ’ N 87 ° 18.82 ’ W) Banco Chinchorro, Quintana Roo, 66.4 m depth, 21 August 1990. ECOSUR P 3194 (1), Cayo Norte, Banco Chinchorro, Quintana Roo, May 1998. Jamaica. UMML 22.1150 (1), R / V Pillsbury, Cruise 7006, Sta. 1195 (17 ° 24 ’ N 76 ° 02 ’ W), SE Jamaica, 14 m depth, 3 July 1970. UMML 22.1149 (1), R / V Pillsbury, Cruise 7006, Sta. 1217 (17 ° 33 ’ N 77 ° 13 ’ W), S Jamaica, 27 m depth, 6 July 1970. UMML 22.1162 (1), R / V Pillsbury, Cruise 7006, Sta. 1230 (17 ° 52 ’ N 77 ° 58 ’ W), SW Jamaica, 31 m depth, 7 July 1970. UMML 22.1151 (1), R / V Pillsbury, Cruise 7006, Sta. 1233 (17 ° 60 ’ N 78 ° 05 ’ W), SW Jamaica, 21 m depth, 7 July 1970. UMML 22.1152 (1), R / V Pillsbury, Cruise 7006, Sta. 1258 (17 ° 03 ’ N 78 ° 10 ’ W), Pedro Bank, 15 m depth, 15 July 1970. UMML 22.1153 (1), R / V Pillsbury, Cruise 7006, Sta. 1259 (17 ° 04 ’ N 77 ° 55 ’ W), S Jamaica, 11 m depth, 15 July 1970. UMML 22.1165 (1), R / V Pillsbury, Cruise 7006, Sta. 1196 (17 ° 28 ’ N 75 ° 57 ’ W), SE Jamaica, 26 m depth, 3 July 1970. ECOSUR P 3111 (3), R / V Pillsbury, Cruise 7006, Sta. 1250 (17 ° 20 ’ N 78 ° 48 ’ W), SW Jamaica, 24 m depth, 14 July 1970. Antigua and Barbuda. UMML 22.1154 (1), R / V Pillsbury, Cruise 6907, Sta. 966 (17 ° 08 ’ N 62 ° 03 ’ W), NW Antigua, 18 m depth, 20 July 1969. UMML 22.1155 (7), R / V Pillsbury, Cruise 6802, Sta. 975 (17 ° 29 ’ N 61 ° 55 ’ W), SW Barbuda, Lesser Antilles, 29 m depth, 21 July 1969. UMML 22.1156 (1), R / V Pillsbury, Cruise 6907, Sta. 967 (17 ° 16 ’ N 62 ° 02 ’ W), NW Antigua, 22 m depth, 20 July 1969. ECOSUR P 3112 (2), R / V Pillsbury, Cruise 6806, Sta. 968 (17 ° 18 ’ N 61 ° 52 ’ W), N Antigua, Lesser Antilles, 18 m depth, 20 July 1969. Saint-Barthélemy. UMML 22.1179 (1), R / V Pillsbury, Cruise 6907, Sta. 981 (18 ° 01 ’ N 62 ° 55 ’ W), Saint-Barthélemy Channel, Lesser Antilles, 22 m depth, 22 July 1969. UMML 22.1157 (1), R / V Pillsbury, Cruise 6806, Sta. 979 (17 ° 51 ’ N 62 ° 39 ’ W), ESE Saint-Barthélemy, Lesser Antilles, 37 m depth, 22 July 1969. Anguilla. UMML 22.1158 (1), R / V Pillsbury, Cruise 6907, Sta. 983 (18 ° 20 ’ N 62 ° 38 ’ W), S Anguilla Valley, Lesser Antilles, 49 m depth, 22 July 1969. St. Kitts and Nevis. ECOSUR P 3113 (2) R / V Pillsbury, Cruise 6802, Sta. 955 (17 ° 04 ’ N 62 ° 34 ’ W), S Nevis, Lesser Antilles, 11 m depth, 19 July 1969. UMML 22.1159 (8), R / V Pillsbury, Cruise 6907, Sta. 961 (17 ° 27 ’ N 62 ° 51 ’ W), NW St. Kitts, Lesser Antilles, 11 m depth, 19 July 1969. Guadeloupe. UMML 22.1160 (1), R / V Pillsbury, Cruise 6907, Sta. 939 (16 ° 22 ’ N 61 ° 09 ’ W), NW La Désirade, Lesser Antilles, 95 m depth, 16 July 1969. Caribbean Netherlands. UMML 22.1161 (2), R / V Pillsbury, Cruise 6907, Sta. 965 (17 ° 26 ’ N 63 ° 23 ’ W), Saba Bank, 24 m depth, 20 July 1969. Type locality. Buenavista, Quintana Roo, Mexico (18 ° 30 ’ 42 ’’ N 87 ° 45 ’ 30 ” W).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF433FFBBF89BFE68FDECDD0C.taxon	etymology	Etymology. Named after the late Nancy Voss (UMML), an eminent cephalopod researcher and marine biologist, for making available a large number of specimens for this study.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF433FFBBF89BFE68FDECDD0C.taxon	description	Description of atoke. Holotype (ECOSUR 0248) complete, in good condition, 18.5 mm long, 0.9 mm wide at chaetiger 10 excluding parapodia, 65 chaetigers (Fig. 13 A). Paratype (ECOSUR 0249) incomplete, 21 mm long, 1.5 mm wide at chaetiger 10 excluding parapodia, 44 chaetigers. Non-type specimens used to illustrate pharynx; one specimen 4 mm long, 1 mm wide, 17 chaetigers (ECOSUR P 3112); another specimen 9 mm long, 1 mm wide, 33 chaetigers (ECOSUR P 3113). Body whitish or pale, glandular masses or pigmentation not observed (Fig. 13 A – C). Prostomium 1.5 x longer than wide, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 13 C – E). Antennae subulate, 1.6 x longer than prostomium, shorter than palps (Fig. 13 C – E). Palpophores subcylindrical or digitiform, 1.5 x longer than prostomium; tips of palpostyles subpyriform (Fig. 13 D – E). Eyes rounded, subequal, in trapezoidal arrangement, blackish, slightly wider than basal diameter of antennae, lenses not visible, posterior pair not covered by achaetous ring (Fig. 13 C – E). Achaetous ring shorter than chaetiger 1, anterior margin convex (Fig. 13 C – E). Tentacular cirri smooth, posterodorsal cirri extending backwards to chaetigers 13 – 14 (Fig. 13 A, C – D). Pharynx examined by dissection in holotype (Fig. 13 A, C), everted in non-type specimen (Fig. 13 D – E). Jaws amber, 4 teeth restricted to first third of cutting edge and 4 ensheathed (Fig. 14 Q). Maxillary ring cylindrical, oral ring frustum-shaped, twice longer and 1.7 x wider than maxillary ring (Fig. 13 D – E). Maxillary ring: I = 0; IIa = 9 and IIb = 10 cones in arc; III = 5 cones in round; IVa = 8 and IVb = 9 cones in round (Fig. 13 D – E). Oral ring: V = 0; VIa-b = 1 slightly lamelliform papilla; VII – VIII = 0 (Fig. 13 D – E). Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Dorsal cirri filiform, progressively relatively longer; 2.8 x longer than neuroacicular ligule in chaetiger 2, 5 x longer in chaetiger 8, 10.2 x longer in chaetiger 17, 6 x longer in chaetiger 39, 8.3 x longer in chaetiger 57 (Fig. 14 A – J). Dorsal ligule subulate or subconical, progressively shorter toward posterior chaetigers, present throughout; 1.2 x longer than neuroacicular ligule in chaetiger 8, 0.6 x length in chaetiger 17, 0.2 x length in chaetiger 39, 0.2 x length in chaetiger 57 (Figs 2 B, D; 14 A – J). Notopodial prechaetal lobe absent throughout (Figs 2 B, D; 14 A – J). Median ligule subconical, progressively shorter toward posterior chaetigers; 0.8 x length than neuroacicular ligule in chaetiger 8, 0.7 x length in chaetiger 17, 0.9 x length in chaetiger 39, 1.2 x longer in chaetiger 57 (Figs 2 B, D; 14 A – J). Neuroacicular ligule subconical throughout, progressively relatively shorter toward posterior chaetigers. Neuropodial superior and inferior lobes absent (Figs 2 B, D; 14 A – J). Neuropodial postchaetal digitiform in most anterior chaetigers, becoming lamelliform and shorter than neuroacicular ligules thereafter (Fig. 2 B, D), disappearing toward most posterior chaetigers. Ventral ligule digitiform throughout, progressively shorter toward posterior chaetigers; 1.2 x longer than neuroacicular ligule in chaetiger 2, 0.7 x length in chaetiger 8, 0.6 x length in chaetiger 17, 0.3 x length in chaetiger 39, 0.4 x length in chaetiger 57 (Figs 2 B, D; 14 A – J). Ventral cirrus filiform, not extending beyond tip of neuroacicular ligule; twice longer than neuroacicular ligule in chaetiger 2, 1.5 x longer in chaetiger 8, 1.5 x longer in chaetiger 17, 1.3 x longer in chaetiger 39, 1.8 x longer in chaetiger 57 (Fig. 14 A – J). Aciculae amber throughout. Notoaciculae present in first two chaetigers (Fig. 14 A, F). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 14 A – J). Notochaetae both short-bossed heterogomph spinigers and falcigers; spinigers in all chaetigers, pectinate, teeth minute, decreasing in size toward tip; falcigers appearing from chaetigers 15 – 17, pectinate, teeth coarse, distal teeth barely extending beyond blade tip, blade tip with a distal tooth, giving a bifid appearance (Fig. 14 K – L), shaft becoming slightly stouter toward posterior chaetigers (Fig. 14 K – L). Supracicular neurochaetae short-bossed heterogomph spinigers and long-bossed heterogomph falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, basal teeth minute and increasing in size toward distal blade, distal teeth rarely extending beyond blade tip, blade tip rounded along first 15 – 16 chaetigers, with a distal tooth and bifid appearance thereafter, blades becoming narrower toward posterior chaetigers (Fig. 14 N). Infracicular neurochaetae both long-bossed heterogomph spinigers and falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, basal teeth minute and increasing in size toward distal blade (Fig. 14 O – P), distal teeth rarely extending beyond blade tip, blade tip rounded along first 15 – 16 chaetigers, with a distal tooth and bifid appearance thereafter, distal tooth poorly developed and sometimes distal tip almost rounded (Fig. 14 O – P), blades longer in anterior chaetigers (Fig. 14 M) and becoming shorter toward posterior ones (Fig. 14 O – P), blades becoming narrower toward posterior chaetigers (Fig. 14 O), uppermost falcigers with longer and wider blades than lowermost ones. Pygidium tripartite (Fig. 13 B); anal cirri missing in holotype (Fig. 13 B). Description of male epitoke. Non-type male (ECOSUR P 1152) complete, 6.2 mm long, 0.5 mm wide at chaetiger 10 excluding parapodia, 56 chaetigers (Fig. 15 A). Another non-type male (ECOSUR P 1156) incomplete, 5.8 mm long, 1 mm wide at chaetiger 10 excluding parapodia, 29 chaetigers (Fig. 15 B). Body pale or yellowish, pigmentation absent (Fig. 15 A – B). Prostomium 1.4 x – 1.7 x wider than long, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 15 A – B, D – E). Antennae subulate, as long as prostomium, not extending beyond palps (Fig. 15 A – B, D – E). Eyes rounded, subequal, in trapezoidal arrangement, anterior and posterior pair overlapped, blackish, twice wider than basal diameter of antennae, lenses visible, posterior not covered by achaetous ring (Fig. 15 A – B, D – E). Achaetous ring as long as chaetiger 1, anterior margin convex (Fig. 15 A – B, D – E). Tentacular cirri smooth (Fig. 15 B), posterodorsal cirri extending backwards to chaetigers 14 – 15 (Fig. 15 B). Pharynx dissected. Shape and size of both maxillary and oral rings difficult to interpret since the pharynx was not everted. Maxillary ring: I = 0; IIa = 10 and IIb = 12 cones in arc, III = 6 cones in round, IVa = 11 and IVb = 12 cones in ellipse. Oral ring: V = 0; VIa-b = 1 rounded papilla, VII-VIII = 0. Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Body divided into three regions: 1) pre-natatory region includes chaetigers 1 – 15 (15 – 16), 2) natatory region includes chaetigers 16 – 36 (36 – 37), 3) caudal region from chaetiger 37 (37 – 38) to end of body (Fig. 15 A). Pre-natatory region with parapodia resembling atokous ones (Fig. 16 A – B, D). Dorsal cirrus basally slightly swollen in anterior chaetigers and becoming filiform toward posterior chaetigers; 4.5 x longer than neuroacicular ligule in chaetiger 2, 6 x longer in chaetiger 3, 5.5 x longer in chaetiger 7 (Fig. 16 A – B, D). Dorsal ligule digitiform, progressively relatively longer toward middle chaetigers; 1.2 x longer than neuroacicular ligule in chaetiger 3, 1.6 x longer in chaetiger 7 (Fig. 16 B, D). Notopodial prechaetal lobe absent (Fig. 16 A – B, D). Median ligule subconical, progressively relatively longer toward middle chaetigers; 1.5 x longer than neuroacicular ligule in chaetiger 3, 1.8 x longer in chaetiger 7 (Fig. 16 A – B, D). Neuroacicular ligule subconical, progressively relatively longer toward middle chaetigers (Fig. 16 A – B, D). Neuropodial inferior lobe digitiform in anterior chaetigers, absent toward posterior ones (Fig. 16 A – B, D). Neuropodial postchaetal lobe digitiform in anterior chaetigers, lamelliform and shorter than neuroacicular ligule thereafter. Ventral ligule subconical, 2.3 x longer than neuroacicular ligule in first two chaetigers, 1.5 x longer in chaetiger 3, as long as in chaetiger 7 (Fig. 16 A – B, D). Ventral cirrus basally swollen in anterior chaetigers and becoming filiform toward posterior chaetigers; 4 x longer than neuroacicular ligule in chaetiger 2, 2.5 x longer in chaetiger 7 (Fig. 16 A, D). Natatory region with dorsal cirrus filiform, crenulations absent; twice longer than neuroacicular ligule throughout (Fig. 16 E – F). Dorsal ligule obovate; 0.3 x length of neuroacicular ligule in anterior chaetigers, 0.2 x length thereafter (Fig. 16 E – F). Notopodial prechaetal lobe rounded, lamelliform; 0.6 x length of neuroacicular ligule in anterior chaetigers, 0.8 x length thereafter (Fig. 16 E – F). Median ligule subconical, 1.2 x longer than neuroacicular ligule in anterior chaetigers, 1.4 x longer thereafter (Fig. 16 E – F). Neuroacicular ligule subconical, progressively relatively shorter toward posterior chaetigers, distally flattened (Fig. 16 E – F). Neuropodial superior and inferior lobes absent (Fig. 16 E – F). Neuropodial postchaetal lobe transformed into flabelliform ventral lamella, 1.8 x longer than neuroacicular ligule in anterior chaetigers, as long as toward posterior chaetigers (Fig. 16 E – F), reaching and fusing with ventral ligule (Fig. 16 E – F). Ventral ligule rounded; 0.3 x length of neuroacicular ligule throughout (Fig. 16 E – F). Ventral cirrus filiform; 0.7 x length of neuroacicular ligule in anterior chaetigers, as long as toward posterior ones (Fig. 16 E – F); upper and lower lamella appearing in anterior chaetigers and disappearing toward posterior ones, upper and lower ones obovate and subequal (Fig. 16 F). Caudal region with parapodia resembling atokous ones (Fig. 16 C). Dorsal cirrus filiform, 12 x longer than neuroacicular ligule (Fig. 16 C). Dorsal ligule absent (Fig. 16 C). Medial ligule subconical, progressively relatively shorter toward posterior chaetigers; 1.4 x longer than neuroacicular ligule (Fig. 16 C). Neuroacicular ligule subconical, mucronate (Fig. 16 C), progressively relatively shorter toward posterior chaetigers. Ventral ligule digitiform, 0.2 x length of neuroacicular ligule (Fig. 16 C). Ventral cirrus filiform, extending beyond tip of neuroaciculae; 2.5 x longer than neuroacicular ligule (Fig. 16 C). Aciculae amber throughout. Notoaciculae present in first two chaetigers (Fig. 16 A). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 16 A – E). Both noto- and neurochaetae resembling atokous ones in pre-natatory region, replaced with paddle-like, shortbossed heterogomph chaetae in natatory region. Caudal region lacks chaetae excepting aciculae. Pygidium with four rounded lobes, each one with a small lamella; anal cirri absent (Fig. 15 C).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF433FFBBF89BFE68FDECDD0C.taxon	discussion	Remarks. Ceratonereis nancyae n. sp. closely resembles C. mirabilis, mainly in prostomial and chaetal features, but they differ in the following parapodial features: 1) in C. nancyae n. sp., the jaws are narrower than in C. mirabilis; 2) in C. nancyae n. sp., ventral ligules of chaetigers 10 – 13 are shorter than neuroacicular ligules, whereas in C. mirabilis they are longer; 3) in C. nancyae n. sp., both median ligules and ventral cirri from chaetigers 23 – 25 are shorter than neuroacicular ligules, whereas in C. mirabilis they are longer; 4) in C. nancyae n. sp. ventral cirri does not surpass neuroacicular ligules throughout body, whereas in C. mirabilis they extend beyond in posterior chaetigers. Records of C. mirabilis by Liñero-Arana & Díaz-Díaz (2007) from Venezuela more closely resembles C. nancyae n. sp. than C. mirabilis, but they differ in the following features: 1) in specimens from Venezuela, longest tentacular cirri reach chaetiger 6, whereas in C. nancyae n. sp. they reach 13 – 14; 2) in specimens from Venezuela, anterodorsal tentacular cirri are subequal to posterodorsal ones, whereas in C. nancyae n. sp. they are longer; 3) in specimens from Venezuela, dorsal ligules in chaetiger 25 are as long as median ligules, whereas in C. nancyae n. sp. they are much shorter; 4) in specimens from Venezuela, palps are as long as prostomium and antenna are shorter than prostomium, whereas in C. nancyae n. sp. they are longer. Based on these differences, Venezuelan specimens likely belong to an undescribed species, requiring further examination of specimens.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF433FFBBF89BFE68FDECDD0C.taxon	distribution	Distribution. Caribbean Sea.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF438FF85F89BFE68FDDBDE70.taxon	description	Figures 2 A, C; 17 – 19	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF438FF85F89BFE68FDDBDE70.taxon	materials_examined	Type material. Tropical Eastern Pacific, Mexico. Holotype male AMNH 1986, San Jose Island, Baja California Sur, Gulf of California, 25 March 1911, Coll. CH Townsend. Additional type material. Holotype of Nereis singularis Treadwell, 1943 USNM 20092, 42.45, - 47.1083, collected from surface, 8 August 1928, Coll. Carnegie Institution of Washington. Paratype (fide AMNN records) AMNH 2129, 42 º 10 ’ N 47 º 19 ’ W, Coll. Cruise of the non-magnetic ship, Carnegie Plankton Collection. Additional material. Tropical Eastern Pacific, Mexico. LACM-AHF 7408 (2), R / V Velero III, Sta. 1093 - 40 (25 ° 49 ’ 25 ” N 111 ° 18 ’ 35 ” W), Puerto Escondido, Baja California Sur, 15 – 27 m depth, 10 February 1940, Coll. Allan Hancock Foundation (AHF). LACM-AHF 7410 (2), R / V Velero III, Sta. 1903 - 40 (25 ° 49 ’ 25 ” N 111 ° 18 ’ 35 ” W), Puerto Escondido, Baja California Sur, 15 - 27 m depth, 10 February 1940, Coll. AHF. LACM-AHF 7411 (5), R / V Velero III, Sta. 662 - 37 (25 ° 31 ’ 35 ” N 111 ° 01 ’ 45 ” W), off San Marcial Reef, Agua Verde Bay, Baja California Sur, 15 m depth, 11 March 1937, Coll. AHF. LACM-AHF 7412 (1), R / V Velero III, Sta. 683 - 37 (26 ° 53 ’ 50 ” N 111 ° 52 ’ 25 ” W), off Bahia Concepcion, Baja California, 22 m depth, 15 March 1937, Coll. AHF. LACM-AHF 7413 (1), R / V Velero IV, Sta. 2024 - 51 (27 ° 48 ’ 33 ” N 114 ° 42 ’ 30 ” W to 27 ° 49 ’ 00 ” N 114 ° 42 ’ 09 ” W), Scammon’s Lagoon, Baja California Sur, 13 - 16 m depth, 18 Apil 1951, Coll. AHF. LACM-AHF 7415 (1), R / V Velero III, Sta. 277 - 34 (21 ° 51 ’ 35 ” N, 105 ° 54 ’ 30 ” W), Isabel Island, Nayarit, 18 - 46 m depth, 5 March 1934, Coll. AHF. LACM-AHF 7416 (3), R / V Velero IV, Sta. 1101 - 40 (25 ° 31 ’ 00 ” N, 111 ° 01 ’ 45 ” W), Agua Verde Bay, Baja California Sur, 18 m depth, 12 February 1940, Coll. AHF. LACM-AHF 7417 (2), R / V Velero III, Sta. 1103 - 40 (25 ° 31 ’ 05 ” N, 111 ° 02 ’ 30 ” W), Agua Verde Bay, Baja California Sur, shore, 12 February 1940, Coll. AHF. AMNH 1913 (75 males), San Jose Island, Baja California Sur, Gulf of California, electric light, April 1911, Coll. U. S. S. Albatross. AMNH 1950 (30 males), SE side Carmen Island, Baja California Sur, Gulf of California, electric light, 1911, Coll. U. S. S. Albatross.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF438FF85F89BFE68FDDBDE70.taxon	description	Description of male epitoke. Holotype male (AMNH 1986) complete, 15 mm long, 1.5 mm wide at chaetiger 10 excluding parapodia, 65 chaetigers (Fig. 17 A); three parapodia previously dissected, anal cirri missing, dissections avoided to prevent further damage. Additional material (AMNH 1930 and AMNH 1950) consists of several males, all in good condition, one male (AMNH 1950) selected for description (Figs 2 A, 17 B), 28.5 mm long, 2.8 mm wide at chaetiger 10 excluding parapodia, 73 chaetigers. Body pale or yellowish, brownish pigmentation in anterior chaetigers (Fig. 17 A – B). Prostomium 1.3 x wider than long, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 17 A – C). Antennae lanceolate, 1.5 x longer than prostomium, not extending beyond palps (Figs 2 A, 17 A – C). Eyes rounded, subequal, in trapezoidal arrangement, anterior and posterior pair overlapped, blackish, as wide as basal diameter of antennae, lenses visible, posterior not covered by achaetous ring (Figs 2 A, 17 A – C). Achaetous ring as long as chaetiger 1, anterior margin convex (Figs 2 A, 17 A – C). Most tentacular cirri detached, remaining smooth (Figs 2 A, 17 A – C). Pharynx everted in holotype (Fig. 17 E) and in non-type specimen (Fig. 17 F – G). Jaws amber, 7 teeth along cutting edge (Fig. 18 G). Maxillary ring cylindrical, oral ring frustum-shaped, 1.8 x longer and 1.4 x wider than maxillary ring (Fig. 17 E – G). Maxillary ring: I = 0; IIa = 11 and IIb = 12 cones in arc; III = 10 cones in round; IVa = 16 and IVb = 18 cones in round (Fig. 17 E – G). Oral ring: V = 0; VIa-b = 1 rounded papilla; VII – VIII = 0 (Fig. 17 E – G). Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Body divided into three regions: 1) pre-natatory region includes chaetigers 1 – 16 (15 – 16), 2) natatory region includes chaetigers 17 – 37 (36 – 37), 3) caudal region from chaetiger 38 (37 – 38) to end of body (Fig. 17 A – B). Pre-natatory region with parapodia resembling atokous ones (Figs 2 A, 18 A – B). Dorsal cirrus basally slightly swollen in anterior chaetigers and becoming filiform toward posterior chaetigers; 3.6 x longer than neuroacicular ligule in chaetigers 7 and 14 (Fig. 18 A – B); upper lamella present from chaetiger 14 (Fig. 18 B). Dorsal ligule digitiform, progressively relatively longer toward middle chaetigers; as long as neuroacicular ligule in chaetiger 7, 1.4 x longer than in chaetiger 14 (Fig. 18 A – B). Notopodial prechaetal lobe absent (Fig. 18 A – B). Median ligule subconical, progressively relatively longer toward middle chaetigers; 1.5 x longer than neuroacicular ligule in chaetiger 7, 1.7 x longer in chaetiger 14 (Fig. 18 A – B). Neuroacicular ligule subconical, progressively relatively longer toward middle chaetigers (Fig. 18 A – B). Neuropodial superior and inferior lobes absent (Fig. 18 A – B). Neuropodial postchaetal lobe digitiform in anterior chaetigers, lamelliform and shorter than neuroacicular ligule thereafter. Ventral ligule subconical, 0.7 x length of neuroacicular ligule in chaetigers 7 and 14 (Fig. 18 A – B). Ventral cirrus slightly basally swollen in anterior chaetigers and becoming filiform toward posterior chaetigers; 2.2 x longer than neuroacicular ligule in chaetiger 7 (Fig. 18 A). Natatory region with dorsal cirrus filiform, crenulations absent; twice longer than neuroacicular ligule throughout (Figs 2 C; 18 C – D). Dorsal ligule subconical in anterior chaetigers, basally swollen thereafter; 0.7 x length of neuroacicular ligule thereafter (Figs 2 C; 18 C – D). Notopodial prechaetal lobe rounded, lamelliform; half as long as neuroacicular ligule in anterior chaetigers, as long as thereafter (Figs 2 C; 18 C – D). Median ligule subconical, progressively relatively shorter toward posterior chaetigers; as long as neuroacicular ligule throughout (Figs 2 C; 18 C – D). Neuroacicular ligule subconical, mucronate, progressively relatively shorter toward posterior chaetigers, distally slightly flattened (Fig. 18 C – D). Neuropodial inferior lobe present throughout (Figs 2 C; 18 C – D). Neuropodial postchaetal lobe transformed into flabelliform ventral lamella, half as long as neuroacicular ligule throughout (Figs 2 C; 18 C – D), reaching and fusing with ventral ligule, forming a ligule (Figs 2 C; 18 C – D). Ventral ligule subconical; 0.4 x length of neuroacicular ligule throughout (Figs 2 C; 18 C – D). Ventral cirrus filiform; 0.4 x length of neuroacicular ligule in anterior chaetigers, 0.6 x length thereafter (Figs 2 C; 18 C – D); upper and lower lamella appearing in anterior chaetigers and disappearing toward posterior ones, upper and lower ones obovate and subequal (Fig. 18 C). Caudal region with parapodia resembling atokous ones (Fig. 18 E – F). Dorsal cirrus filiform, 9 x longer than neuroacicular ligule (Fig. 18 E). Dorsal ligule subconical, half as long as neuroacicular ligule throughout (Fig. 18 E – F). Medial ligule subconical, progressively relatively longer toward posterior chaetigers; as long as neuroacicular ligule in anterior chaetigers, 1.7 x longer than thereafter (Fig. 18 E – F). Neuroacicular ligule subconical, pointed tip, progressively relatively shorter toward posterior chaetigers. Ventral ligule digitiform, 0.4 x length of neuroacicular ligule throughout (Fig. 18 E – F). Ventral cirrus filiform, extending beyond tip of neuroacicular ligule; 1.8 x longer than neuroacicular ligule in anterior chaetigers, 5 x longer thereafter (Fig. 18 E – F). Aciculae proximal end dark brown and distal end amber throughout, amber in posteriormost chaetigers (Fig. 18 A – F). Notoaciculae present in first two chaetigers. Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 18 A – F). Both noto- and neurochaetae resembling atokous ones in pre-natatory region (Fig. 18 H – I), replaced with paddlelike, short-bossed heterogomph chaetae in natatory region. Caudal region lacks chaetae excepting aciculae. Pygidium with four rounded lobes, each one with a small lamella; anal cirri absent (Fig. 17 D). Description of atoke. Largest one used for description (LACM-AHF 7411), 26 mm long, 2 mm wide excluding parapodia, 45 chaetigers; another specimen (LACM-AHF 7410) in fair condition, 22 mm long, 1.2 mm wide excluding parapodia, 66 chaetigers. Body pale or yellowish; brown pigmentation present, with a brown, cordiform spot in posterior margin of prostomium, between eyes, and dorsal striate pattern in anterior chaetigers (Fig. 19 A). Prostomium 1.5 x wider than long, subpentagonal, anterior margin deeply incised, dorsal groove present (Fig. 19 A). Antennae lanceolate, twice longer than prostomium, not extending beyond palps (Fig. 19 A). Eyes rounded, subequal, in trapezoidal arrangement, blackish, as wide as basal diameter of antennae, lenses not visible, posterior pair not covered by achaetous ring (Fig. 19 A). Achaetous ring as long as chaetiger 1, anterior margin convex (Fig. 19 A). Tentacular cirri smooth (Fig. 19 A), posterodorsal cirri extending backwards to chaetiger 16. Pharynx dissected. Jaws brown with 4 teeth extended along cutting edge and 3 ensheathed (Fig. 19 C). Shape and size of both maxillary and oral rings difficult to interpret since the pharynx was not everted. Maxillary ring: I = 0; IIa = 16 and IIb = 16 cones in ellipse; III = 9 cones in round; IVa = 18 and IVb = 19 cones in ellipse. Oral ring: V = 0; VIa-b = 1 rounded papilla; VII-VIII = 0. Ridge pattern of areas VI – V – VI, λ-shaped. Paired oesophageal caeca absent. Dorsal cirri filiform, progressively relatively longer; 3.6 x longer than neuroacicular ligule in chaetiger 1, 9.2 x longer in chaetiger 10, 8.6 x longer in chaetiger 29, 10.3 x longer in chaetiger 44, 16.9 x longer in chaetiger 59 (Fig. 19 D – H). Dorsal ligule subconical, progressively shorter and becoming digitiform toward posterior chaetigers, present throughout chaetigers; 2 x longer in chaetiger 10, 1.3 x longer in chaetiger 29, 0.5 x length in chaetiger 44, 1.2 x longer in chaetiger 59 (Fig. 19 D – H). Notopodial prechaetal lobe absent throughout (Fig. 19 D – H). Median ligule subconical, progressively shorter toward posterior chaetigers; 2.2 x longer in chaetiger 10, 1.6 x longer in chaetiger 29, 1.2 x length in chaetiger 44, 2.6 x longer in chaetiger 59 (Fig. 19 D – H). Neuroacicular ligule subconical throughout, progressively relatively shorter toward posterior chaetigers. Neuropodial superior and inferior lobes absent (Fig. 19 A – D). Neuropodial postchaetal lobe digitiform in first two chaetigers, lamelliform and shorter than neuroacicular ligules thereafter, disappearing toward most posterior chaetigers (Fig. 19 D – H). Ventral ligule subconical to digitiform throughout, progressively shorter toward posterior chaetigers; 2.2 x longer than neuroacicular ligule in chaetiger 1, as long as in chaetiger 10, 0.7 x length in chaetiger 29, 0.5 x length in chaetiger 44, 1.3 x longer in chaetiger 59 (Fig. 19 D – H). Ventral cirrus filiform, extending beyond tip of neuroacicular ligule in posteriormost chaetigers; 5.8 x longer than neuroacicular ligule in chaetiger 1, 2.8 x longer in chaetiger 10, 2.2 x longer in chaetiger 29, 2.5 x length in chaetiger 44, 4.8 x longer in chaetiger 59 (Fig. 19 D – H). Aciculae dark brown in anterior and middle chaetigers, amber in posterior chaetigers (Fig. 19 D – H). Notoaciculae present in first two chaetigers (Fig. 19 D). Notoaciculae narrower than neuroaciculae in anterior chaetigers, becoming as wide as in following chaetigers (Fig. 19 D – H). Notochaetae both short-bossed heterogomph spinigers and falcigers; spinigers in all chaetigers, pectinate, teeth minute, decreasing in size toward tip; falcigers appearing from chaetigers 14 – 17, pectinate, basal teeth minute and greatly increasing in size toward distal blade, distal teeth extending beyond blade tip, blade tip rounded (Fig. 19 I), shaft becoming slightly stouter toward posterior chaetigers. Supracicular neurochaetae short-bossed heterogomph spinigers and long-bossed heterogomph falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, basal teeth minute and greatly increasing in size toward distal blade, distal teeth extending beyond blade tip (Fig. 19 J), blades becoming wider toward posterior chaetigers. Infracicular neurochaetae both long-bossed heterogomph spinigers and falcigers; spinigers with blades as in notopodial ones; falcigers pectinate, basal teeth minute and greatly increasing in size toward distal blade (Fig. 19 K – L), distal teeth extending beyond blade tip, blade tip rounded throughout (Fig. 19 K – L), blades becoming narrower toward posterior chaetigers, uppermost falcigers with longer and wider blades than lowermost ones (Fig. 19 K – L). Pygidium minute, bilobate; anal cirri filiform, as long as last six chaetigers (Fig. 19 B).	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF438FF85F89BFE68FDDBDE70.taxon	discussion	Remarks. Salazar-Vallejo & Jiménez-Cueto (1997) examined the holotype and mentioned it consisted of two portions and missing the pharynx, but neither the holotype nor additional AMNH materials examined have such damage. Also, the latter authors thought that ‘ pre-pygidial portion’ was in the process of regeneration, perhaps by the distinct size especially when they are compared with chaetigers from pre-natatory and natatory regions; however, the presence of this feature in all epitokes of Ceratonereis herein described and the lack of chaetae in such chaetigers suggest it is an epitoke-related modification and not posterior portions undergoing regeneration. Hartman (1956) regarded C. singularis as a junior synonym of C. mirabilis without further explanation. Also, Hartman (1956) suggested, without explanation, that Nereis singularis Treadwell, 1943, a species collected from Newfoundland Basin, might be another synonym. The holotype (USNM 20092; 8 mm long, 0.5 mm wide at chaetiger 10 excluding parapodia, 52 chaetigers, longest tentacular cirri reach chaetiger 11) and the paratype (AMNH 2129; 7 mm long, 0.5 mm wide at chaetiger 10 excluding parapodia, 29 chaetigers, specimen friable) of Nereis singularis Treadwell, 1943, were examined (Fig. 20). After a close examination of the type series, N. singularis was found to be a Platynereis species based on the following features: 1) anterior margin of prostomium entire (Fig. 20 A – B, D); 2) palpophores globose (Fig. 20 A – B); 3) presence of rod-like paragnaths in the pharynx (observed in holotype after whole-mounting specimen and using a compound microscope); 4) parapodial processes of similar relative size along the body, especially dorsal ligules; 5) presence of symmetrical homogomph spinigers and falcigers in middle and posterior chaetigers; and 6) notopodial and neuropodial falcigers with blades having a distal incurved hook with a tendon fused to the blade (Fig. 20 E). Therefore, the synonymy of N. singularis with C. mirabilis is rejected, and the new combination Platynereis singularis (Treadwell, 1943) is proposed; future works could address if it is a valid species or not. Perkins (1980) redescribed Ceratonereis singularis based on type material and additional specimens from other localities from Eastern Pacific coasts, but also included Atlantic material, regarding C. singularis as an amphiamerican species. However, his Atlantic specimens resemble C. maya n. sp. as well as the material identified as C. singularis by Salazar-Vallejo & Jiménez-Cueto (1997); further comments are in remarks of C. maya n. sp. above. The species have been recorded in several localities of the Caribbean Sea (Dean 2012), but they likely belong to C. maya n. sp.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
4E3F87EAF438FF85F89BFE68FDDBDE70.taxon	distribution	Distribution. Mexican Pacific.	en	Conde-Vela, Víctor Manuel (2021): Revision of Ceratonereis Kinberg, 1865 recorded from the Caribbean Sea, with description of two new Ceratonereis species and a new combination of Platynereis Kinberg, 1865. Zootaxa 5026 (3): 301-343, DOI: 10.11646/zootaxa.5026.3.1
