taxonID	type	description	language	source
03D887BE630C8409C7794DC40A27FD7E.taxon	diagnosis	Diagnosis. Shell with 6 plates, rostrum and carina with radii, rostrolaterals without radii, carinolateral lacking, mandibles with 4 teeth, bases membranous, Cirri I-II maxillipedes, III-VI ctenopods.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE630C8402C7794EF60BB8FA77.taxon	etymology	the authority for this species name change rests with BKK Chan	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE630C8402C7794EF60BB8FA77.taxon	description	Figs 2 A and 2 B and 3 – 5	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE630C8402C7794EF60BB8FA77.taxon	etymology	Etymology. Pitombo & Burton [12] stated explicitly that Chthamalus southwardorum is named “ in honor of Dr A. J. Southward, for his extensive contribution to the knowledge of chthamalids and his careful collecting during the Tropical eastern Pacific Expedition ”. Unfortunately, the suffix - orum indicates “ for men or for man (men) and woman (women) together ” (ICZN, 4 th edition, 1999 Article 31.1.2). Since there is clear evidence of a lapsus calami in the original publication (ICZN ART 32.5.1) the name C. southwardorum is not admissible under ICZN Art. 21.13 and has to be treated as an incorrect original spelling that should be corrected to southwardi, taking the authorship and date of Pitombo & Burton [12]. However, Chthamalus southwardi Pitombo & Burton, 2007 is a junior primary homonym of Chthamalus southwardi Poltaruka, 2000 and therefore an invalid name (ICZN Art 57.2) and so a new replacement name is required for C. southwardorum. In the present study, I (BKKC) rename C. southwardorum as Chthamlaus alani, again in honour of Prof. Alan Southward, but using his first name, for his contributions to barnacle distribution, ecology and taxonomy.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE630C8402C7794EF60BB8FA77.taxon	materials_examined	Specimens examined. AJS- 2, 10 specimens, high intertidal shores, La Paz Bay, 24 ° 13 ' N, 110 ° 18.6 ' W, 3 Nov 1978; AJS- 3, 7 specimens, intertidal shores, Point Lobos, Todos Santos, Baja California Sur, Mexico, 23 ° 24.8 ' N, 110 ° 57 ' W, 4 Nov 1978; TEPE 78 - 36, 10 specimens, Ocean Front, Mazatlan, Sinaloa, Mexico, exposed rocky shores with large boulders, 23 ° 11.7 ' N, 106 ° 25.5 ' W, 19 April 1978.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE630C8402C7794EF60BB8FA77.taxon	diagnosis	Diagnosis. Chthamalus with cirrus I having bidenticulate setae with or without basal guards on the distalmost segment of the posterior ramus and cirrus II having bidenticulate setae with basal guards on the two distalmost segments of the posterior ramus and the distalmost segment of the anterior ramus. Tergoscutal flaps orange-brown in colour when alive. COI sequence (Gene Bank Number KU 356723). Description. Shell depressed, sutures between plates visible (Fig 2 A and 2 B). External surface white and smooth, sheath white, with ribs at the basal region, not extending to the apex (Fig 2 A and 2 B). Internal colour of shell white. Orifice oval, scutum and tergum articulated with a marked angle (Figs 2 A and 2 B and 3 D). Tergoscutal flaps orange-brown when alive (Fig 2 A and 2 B), colour fades out when preserved in ethanol or formalin. Scutum triangular, basal margin about twice as long as tergal margin (Fig 3). Tergal margin with a wide and elevated articular ridge, ridge extending beyond the tergal margin, articular furrow wide. Occludent margin straight, without teeth. Adductor muscle pit oval and deep, not extending to the basal margin. Lateral depressor muscle scar deep and smooth (Fig 3). Tergum trapezoid, external surface smooth near the apex, basal region with growth lines or striations, spur wide and not obvious, basal margin with 4 rostral depressor muscle crests (Fig 3). Segment counts on cirri I-III were based on five specimens collected from Mazatlan, Mexico (TEPE- 78 - 36). Segment counts on cirri IV-VI were based on a single specimen from Mazatlan, Mexico (Table 4). Cirrus I: posterior ramus 5 to 6 - segmented (Fig 4 A), the distalmost segment bears bidenticulate setae with or without basal guards (Fig 4 B), serrulate type setae common on all segments of the rami, anterior ramus 6 to 8, serrulate type, setae common on all segments (Fig 4 A, Table 4). Cirrus II: posterior ramus 4 to 7 - segmented, the two distalmost segments bear bidenticulate setae with basal guards, anterior ramus 5 - or 6 - segmented, one or two of the distalmost segments have bidenticulate setae with basal guards, serrulate type setae common on both rami (Fig 4 C and 4 D, Table 4). Cirrus III: anterior and posterior rami similar in length (anterior and posterior rami length ratio = 0.9 ± 0.06), posterior ramus 11 to 16 - segmented, anterior ramus 11 to 16 - segmented (Fig 4 E, Table 4). Cirrus IV: both anterior and posterior rami 16 - segmented (Fig 4 F). Cirrus V: posterior ramus 18 - segmented, anterior ramus 19 - segmented (Fig 4 G). Cirrus VI: posterior ramus 18 - segmented, anterior ramus 19 - segmented (Fig 4 H). Intermediate segments of both rami on cirri III-VI bear two pairs of long serrulate setae and three pairs of shorter simple setae (Fig 4 E – 4 H). Maxilla bilobed, serrulate setae on apex of both lobes and on superior margin (Fig 5 A). Maxillule notched, two large setae above notch, notch small, 8 setae on cutting margin below notch, inferior angle protuberant with bundles of simple setae (Fig 5 B and 5 C). Mandible has 4 major teeth, fourth tooth bidenticulate, pecten with 16 small teeth, inferior angle tipped with two pointed teeth (Fig 5 D and 5 E). Mandibular palp rectangular, serrulate setae on all margins (Fig 5 F). Labrum concave, with 6 – 7 small teeth on both sides of the cutting edge (Fig 5 G and 5 H). Penis without basi-dorsal point.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE630C8402C7794EF60BB8FA77.taxon	distribution	Distribution. Northern limit probably at about 29 ° N inside the Gulf of California and 24 ° 40 ' N on the Pacific coast; southern limit unknown, but probably north of 15 ° N. The holotype and paratypes of C. southwardorum Pitombo & Burton, 2007 were collected in the San Cristovan river estuary, San Blas, Nayarit, Mexico (21 ° 30 ' 54 '' N, 105 ° 15 ' 53 '' W), attached to an oyster shell, low midlittoral zone. Pitombo and Burton stated that the distribution of C. southwardorum was from Bahía Magdalena, Baja California Sur, Mexico to Puerto Chicama, Peru, but they did not distinguish it from the new species C. newmani described below.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE63078403C77949FC0B0CF967.taxon	description	Figs 2 A and 6 – 8	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE63078403C77949FC0B0CF967.taxon	materials_examined	Specimens examined. AJS- 2, 36 specimens, intertidal shores, La Paz Bay, Baja California, 24 ° 13 ' N, 110 ° 18.6 ' W, 3 Nov 1978; AJS- 3, 6 specimens, intertidal shores, Point Lobos, Todos Santos, Baja California Sur, Mexico, 23 ° 24.8 ' N, 110 ° 57 ' W, 4 Nov 1978. TEPE 78 - 24, 12 specimens, intertidal rocks, Isla Cerralvo, Baja California Sur, Mexico, 24 ° 08 ' N, 109 ° 48 ' W, 14 April, 1978; TEPE 78 - 35, 36 specimens, La Paz Promenade, Baja California Sur, Mexico, 24 ° 09 ' N, 110 ° 15 ' W, 18 April, 1978.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE63078403C77949FC0B0CF967.taxon	diagnosis	Diagnosis. Chthamalus with strongly asymmetrical scuta and terga. Orifice often filled by left or right tergum and scutum. Cirrus I distalmost segment of posterior ramus with 2 – 3 bidenticulate setae. Cirrus II with bidenticulate setae with basal guards on the 4 distalmost segments of the posterior ramus and with bidenticulate setae with basal guards on the two distal segments of the anterior ramus. White tergoscutal flaps in fresh specimens.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE63078403C77949FC0B0CF967.taxon	description	Description. Shell white, depressed conic, external surface strongly and irregularly ribbed (Figs 2 A and 6 A). Eroded specimens often have the basal region of the shell ribbe d but the apical region is smooth. Orifice elliptical and often closed by the left tergum and scutum (Figs 2 A and 6 A). Tergoscutal flaps have white edge (Fig 2 A) (the white colour is still visible after preservation in formalin or ethanol). Scutum and tergum strongly asymetrical (Fig 6 B – 6 D). Individuals can have the left scutum and tergum larger than the right scutum and tergum or vice versa (Fig 6 B and 6 D). The larger scutum is triangular, with equal sides, the smaller one is narrower. The external surface of the scutum is smooth with growth lines near the basal margin (Fig 6 C), occludent margin smooth, tergal margin with shallow articular ridge, not extending beyond the tergal margin. Adductor muscle scar oval, lateral depressor muscle scar oval and smooth. Tergum triangular to trapezoid, 3 – 4 lateral depressor muscle crests on basal margin (Fig 6 B and 6 D) Segment counts on cirri I-III were based on five specimens collected from La Paz Bay, Baja California (AJS- 2). Segment counts on cirri IV-VI were based on a single specimen from La Paz Bay, Baja California (AJS- 2) (Table 4). Cirrus I: posterior ramus with 6 or 7 segments, anterior ramus 7 - or 8 - segmented, both rami with serrulate setae dominant, the distalmost segment of the posterior ramus with 2 – 3 bidenticulate setae (Fig 7 A and 7 B, Table 4). Cirrus II: posterior ramus 5 - segmented, anterior ramus 6 - or 7 - segmented, serrulate type setae dominant on both rami. Posterior ramus with bidenticulate setae with basal guards on the 4 distalmost segments (Fig 7 C and 7 D, Table 4), anterior ramus with bidenticulate setae with basal guards on the two distalmost segments (Fig 7 C and 7 E, Table 4). Cirri III-VI: similar in morphology, serrulate type setae dominant, anterior ramus similar in length to the posterior ramus. Cirrus III: anterior ramus 13 to 19 - segmented, posterior ramus 11 to 16 - segmented (Fig 7 F, Table 4). Cirrus IV: anterior ramus 17 - segmented, posterior ramus 15 - segmented (Fig 7 G). Cirrus V and VI: anterior ramus 18 - segmented, posterior ramus 17 - segmented (Fig 7 H). Intermediate segments of anterior rami of cirri IV-VI have 4 pairs of long serrulate setae and 1 pair of short serrulate setae (Fig 7 F – 7 H). Maxilla bilobed, with serrulate setae on both lobes (Fig 8 A). Maxillule notched, 2 large and 4 medium sized setae above notch, 16 setae below notch of cutting margin (Fig 8 B). Mandible has 4 major teeth, first tooth separated from the remainder, fourth tooth bi-dentate. Pecten long and straight, with 30 fine teeth, inferior angle tipped with two pointed teeth (Fig 8 C and 8 D). Mandibular palp rectangular, with serrulate setae on all margins (Fig 8 E and 8 F). Labrum V-shaped, with ~ 10 small teeth on both sides of the cutting margin (Fig 8 G). The middle notch with dense setae (Fig 8 H). Penis without basi-dorsal point.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE63078403C77949FC0B0CF967.taxon	distribution	Distribution. Present in the Gulf of California and on the Pacific coast of Baja California Sur to at least 23 ° 27 ' N.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE63078403C77949FC0B0CF967.taxon	discussion	Remarks. C. anisopoma is sympatric with C. alani nom. nov. and C. hedgecocki on some shores. C. anisopoma can be easily identified in-situ by its strongly asymmetrical opercular plates, also by its white tergoscutal flaps when open under water (Fig 2 A).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6306841AC7794AE60A96FA78.taxon	description	Figs 2 C and 9 – 11	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6306841AC7794AE60A96FA78.taxon	materials_examined	TEPE 78 - 35, 30 specimens, La Paz, Promenade, Baja California Sur, Mexico, 24 ° 09 ' N, 110 ° 15 ' W, 18 April, 1978.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6306841AC7794AE60A96FA78.taxon	diagnosis	Diagnosis. Chthamalus with shell pink-purple to brown externally (white in older and eroded specimens). Outer side of cirrus I with an array of long serrulate setae (one on each segment) on the anterior ramus. Posterior ramus of cirrus I lacks bidenticulate setae. Cirrus II has bidenticulate setae with basal guards on one or two of the distalmost segments of the posterior ramus and the distalmost segment of the anterior ramus. Tergoscutal flaps dull orange-brown in colour, when alive. COI sequence (Gene Bank Numbers: KU 356704 — KU 356705).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6306841AC7794AE60A96FA78.taxon	description	Description. External shell surface pink-purple to white in eroded or bleached specimens, surface ribbed but ribs do not extend to apex (Fig 2 C). Inside of shell pale brown to white. Orifice elliptical. Scutum and tergum slightly asymmetrical, scutum and tergum articulated transversely (Fig 9 A). In older specimens the outer surface of the scutum and tergum was eroded, horizontal growth lines visible on the basal region (Fig 9 B – 9 F). Scutum triangular, tergal margin about half the length of the basal margin, articular ridge not, or seldom, extending beyond the tergal margin, articular furrow deep. Occludent margin without teeth, smooth. Basal margin slightly convex, with obvious lateral depressor muscle crest (Fig 9). Tergum trapezoid, scutal margin slightly convex, spur wide and blunt, carinal margin with 4 – 5 lateral depressor muscle crests (Fig 9 B and 9 E). Segment counts on cirri I-III were based on five specimens collected from Point Lobos, Baja California Sur, Mexico (AJS- 3). Segment counts on cirri IV-VI were based on a single specimen from Point Lobos, Baja California Sur, Mexico (AJS- 3) (Table 4). Cirrus I: posterior ramus 5 – 7 segmented, anterior ramus 7 - to 9 - segmented. Outer side of anterior ramus with a longitudinal array of long, serrulate setae, a single seta on each segment, posterior ramus setae serrulate, no bidenticulate setae (absent from all specimens examined, Fig 10 A). Cirrus II: posterior ramus 5 - to 6 - segmented, anterior ramus 5 - to 6 - segmented, first or first and second most distal segments of the posterior and the most distal segment of the anterior ramus with bidenticulate setae with basal guards (Fig 10 B and 10 D, Table 4). Cirrus III: anterior and posterior rami similar in length, anterior ramus 13 - to 19 - segmented, posterior ramus 14 - to 17 - segmented, intermediate segments have 3 pairs of long setae and 2 pairs of short simple setae (Fig 10 E, Table 4). Cirrus IV and V: anterior and posterior rami 16 - segmented, intermediate segments of both rami carry 3 pairs of long serrulate setae and 2 pairs of short simple setae (Fig 10 F and 10 G). Cirrus VI: anterior and posterior rami 19 - segmented (Fig 10 H). Maxilla with serrulate setae (Fig 11 A). Maxillule notched, two large setae above notch, notch wide and shallow, with 4 – 5 setae in notch, region below notch protuberant, with> 14 setae along the protuberant cutting edge (Fig 11 B). Mandible has 4 major teeth, fourth tooth bi-dentate (Fig 11 C). Pecten long, with 24 very fine teeth, inferior angle with a pair of pointed teeth (Fig 11 D). Mandibular palp rectangular, with serrulate setae on superior margin and tip (Fig 11 E and 11 F). Labrum with V-shaped cutting edge, without sharp teeth on either side of the cutting margin, central part of the notch carries dense setae (Fig 11 G and 11 H). Penis without basi-dorsal point.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6306841AC7794AE60A96FA78.taxon	distribution	Distribution. Southward from 23 ° 39 ' N inside the Gulf of California, on the east coast, and 32 ° 52 ' N on the western outer coast of the Baja California Peninsula. The southern limit is north of 15 ° N on the Mexican Pacific coast. The type material of Chthamalus hedgecocki Pitombo & Burton, 2007 came from Punta Camarón, Mazatlan, Sinaloa, Mexico (23 ° 14 ' 15 '' N, 106 ° 26 ' 45 '' W) attached to rocks on a wave exposed shore, upper midlittoral zone. The geographical distribution was stated by Pitombo and Burton to extend from Baja California to Acapulco in southern Mexico (16 ° 50 ' 19 '' N).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6306841AC7794AE60A96FA78.taxon	discussion	Remarks. Pitombo & Burton [12] reported that the outer surface of the tergum in C. hedgecocki posesses a weak longitudinal furrow, frequently only on one plate. In the present study of specimens from Point Lobos, Baja California, the tergum of C. hedgecocki is smooth externally and without any longitudinal furrows. The arthropodal characters of C. hedgecocki in the present study agree with the descriptions in Pitombo & Burton [12]. The shallow longitudinal furrow in at least one of the the terga of C. hedgecocki may be a variable character and may not be a diagnostic character for species identification.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE631F8412C77949FC0DCAFA4F.taxon	description	Figs 2 D, 2 E and 2 F and 12 – 17	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE631F8412C77949FC0DCAFA4F.taxon	materials_examined	Specimens examined. holotype, NHMUK 2016. 9 (= AJS 1970) 1 specimen from rock ledges, Balboa Statue, Panama City, Panama, 1970; paratypes, NHMUK 2016.10, 2016.11, 2016.12, 2016.13, 2016.14. 5 specimens, same data as holotype. ASIZCR- 000334, 0 0 0 335, 0 0 0 336, 0 0 0 341. 4 specimens, same data as holotype; other materials, TEPE 78 - 1, 20 specimens, intertidal rocks, Farfan Beach, Farfan Point, Panama, 8 ° 56.4 ' N, 79 ° 34.1 ' W, 30 Mar 1978. PWG 1, 6 specimens, intertidal rock, 200 m N of Naos Island on the west side of Avenida Amador, 8 ° 54.63 ' N, 79 ° 31.74 ' W, 3 Feb 1979.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE631F8412C77949FC0DCAFA4F.taxon	diagnosis	Diagnosis. Chthamalus with cirrus I having bidenticulate setae with or without basal guards on the distal segment of the posterior ramus and cirrus II having bidenticulate setae with basal guards on the distalmost two or three segments of the posterior ramus and two distalmost segments of the anterior ramus. External surface of tergum without tergal furrow. Tergoscutal flaps brown when alive. COI sequence (Gene Bank Numbers: KU 356709 — KU 356722).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE631F8412C77949FC0DCAFA4F.taxon	description	Description. The hard parts were described mainly based on the holotype, supplemented with information from paratypes. Shell depressed, white to pale brown, composed of six plates, radii absent. Orifice elliptical (Fig 2 D, 2 E and 2 F). Inside of shell white to pale brown. Scutum and tergum symmetrical, with tergoscutal flaps brown in colour when alive (Fig 2 D, 2 E and 2 F), dull brown when preserved in formalin or ethanol. Scutum triangular, outer surface of scutum with upper part eroded, with growth lines as striation patterns on the lower basal region. Inner side of scutum white, tergal margin with wide articular ridge and deep articular furrow. Basal margin slightly convex, lateral muscle scar present as 1 or 2 pits. Occludent margin straight without dentations, adductor muscle scar oval and deep (Fig 12). Tergum narrow, height of tergum about 1.5 times greater than the width, tergal margin about 0.6 of the length of the basal margin (Fig 12). External surface eroded with growth lines visible near the basal margin, inner side white and smooth, scutal margin strongly concave, carinal margin convex, basal margin with 4 rostral depressor muscle crests. Spur wide and bluntly convex (Fig 12). Segment counts on cirri I-III were based on five specimens collected from rock ledges, Balboa Statue, Panama City, Panama (AJS- 1970) (Table 4). Segment counts on cirri IV-VI were based on the holotype. Cirrus I: posterior ramus with 6 or 7 segments, anterior ramus with 8 or 9 segments (Fig 13 A). Distalmost segment of posterior ramus with 1 – 2 bidenticulate setae with or without basal guards (Figs 13 B, 15 A and 15 C). Serrulate setae dominate on both rami (Fig 15 A – 15 F). Basipod of cirrus I with pappose setae (Fig 15 G). Cirrus II: posterior ramus with 5 to 7 segments, anterior ramus with 7 or 8 segments (Fig 13 C) (Table 4), posterior ramus with bidenticulate setae with basal guards on the three distalmost segments (Fig 13 D), anterior ramus with bidenticulate setae with basal guards on the two distalmost segments (Fig 13 E). The number of basal guards on the bidenticulate setae ranges from 1 – 2 on different specimens (Fig 15 H – 15 P). Serrulate setae are dominant on both rami (Fig 15 R – 15 Q). Basipod with pappose setae. Cirrus III: anterior ramus about equal to posterior ramus, posterior ramus 17 to 19 segments, anterior ramus 18 to 23 segments (Fig 13 G, Table 4). Intermediate segments of cirrus III with 3 pairs of long setae and 2 pairs of short setae (Fig 13 H). Cirrus IV: anterior and posterior rami similar in length, anterior ramus 23 segments, posterior ramus 20 segments (Fig 14 A) intermediate segments of anterior ramus with 3 pairs of long serrulate setae and 2 pairs of short simple setae (Fig 14 B). Cirrus V: anterior and posterior rami similar in length, anterior ramus 21 segments, posterior ramus 20 segments (Fig 14 C), intermediate segments of both rami with 3 pairs of long serrulate setae and 2 pairs of short simple setae (Fig 14 D). Cirrus VI: anterior and posterior rami similar in length, anterior ramus 25 segments, posterior ramus 26 segments (Fig 14 E), intermediate segments of both anterior and posterior rami with 3 pairs of long serrulate and 2 pairs of short simple setae (Fig 14 F). Basipodite (Fig 14 G) and tip of cirrus VI with serrulate setae (Fig 14 H). Maxilla, two lobes are separated by a notch without setae, serrulate setae on both lobes (Figs 16 A and 17 A – 17 C). Maxillule cutting margin notched, with two large setae above notch, five setae below notch, inferior angle protuberant, with dense setae (Figs 16 B, 17 D and 17 E). Mandible has 4 major teeth, first tooth separated from the remainder, the third and fourth teeth bidentate, pecten with 14 very small teeth, inferior angle tipped with a pair of pointed teeth (Figs 16 D and 16 E and 17 G – 17 K). Mandibular palp rectangular, superior margin with dense serrulate setae, inferior margin with long serrulate setae (Figs 16 F and 17 L, 17 M and 17 N). Labrum concave, with six teeth on each side of the cutting margin, central part of notch with dense setae (Figs 16 G and 16 H and 17 P and 17 Q). Penis without basi-dorsal point.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE631F8412C77949FC0DCAFA4F.taxon	distribution	Distribution. Found on the Pacific coast of Central America from 13 ° 55 ' N, 90 ° 47 ' W to 8 ° 51 ' N, 79 ° 44 ' W (range further south unknown).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE631F8412C77949FC0DCAFA4F.taxon	etymology	Etymology. Named (by BKKC) in honour of Prof. William Newman, for his extensive contributions in barnacle taxonomy and his leadership of the TEP Expedition (see Southward [32]).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE631F8412C77949FC0DCAFA4F.taxon	discussion	Remarks. Hedgecock [5] collected specimens which he designated “ FB Chthamalus fissus ” from Farfan Beach, Panama and found identical specimens at Isle del Tigre, Golfo de Fonseca. Using allozyme electrophoresis, he showed these to be a separate species from C. fissus of California and the species collected at Isla Sacrificios and Chamela Bay. Specimens from the Farfan Beach collection of Hedgecock were examined by electrophoresis and by morphology in the present study and found to be C. newmani.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6317842CC77949DE0A34FE20.taxon	description	Figs 2 E and 2 F and 18 – 22	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6317842CC77949DE0A34FE20.taxon	materials_examined	Specimens examined. ANSP (Crustacea) - 2008, type collection of 7 syntypes deposited by Pilsbry 1916, Quarantine Island, Panama (= Naos Island), the intact specimen illustrated in Pilsbry’ s Plate 75, fig 2 a is selected by the present authors as the Lectotype; AJS- 1970. 12 specimens, rock ledges, Balboa Statue, Panama City, Panama. 8 ° 58.1 ' N, 79 ° 32 ' W, 31 Oct 1970; PWG- 1, 10 specimens, intertidal rocks, 200 m N of Naos Island on the west side of Avenida Amador, 8 ° 58.12 ' N, 79 ° 31.81 ' W, 3 Feb 1979.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6317842CC77949DE0A34FE20.taxon	diagnosis	Diagnosis. Chthamalus with a deep longitudinal furrow on outer surface of the tergum, scutal margin of tergum straight. Bidenticulate setae absent from cirrus I. Outer surface of anterior ramus of cirrus I with a longitudinal array of setae. Cirrus II, distalmost segment of both anterior and posterior rami bears bidenticulate setae with basal guards, anterior ramus of cirrus III is about 1.5 times longer than the posterior ramus. Tergoscutal flaps orange. COI sequence (Gene Bank Numbers: KU 356706 — KU 356708).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6317842CC77949DE0A34FE20.taxon	description	Description. Shell pink to purple in unbleached or uneroded specimens, otherwise white, with six plates (Figs 2 E and 2 F and 18 A and 18 B). Surface with ribs extending to the apex. Orifice elliptical. Scutum and tergum articulated slightly obliquely. Scutum triangular, basal margin twice the length of the tergal margin, external surface with horizontal growth lines, and the upper portion often eroded, tergal margin with shallow articular ridge, not extending beyond the tergal margin, occludent margin straight to slightly convex, with teeth on proximal 1 / 3 of the margin in uneroded specimens (Fig 18 C and 18 D). Adductor muscle pit oval, not extending to basal margin. Lateral depressor muscle pit deep and smooth (Fig 18 D – 18 F). Tergum triangular to trapezoid, external surface with horizontal striations and a deep longitudinal furrow is visible in the basal region (Fig 18 D – 18 F). Such a furrow can be observed from above through the orifice of uneroded, undissected specimens (Fig 18 A and 18 B). Inner surface of tergum smooth, scutal margin straight, spur flat and not obvious, depressor muscle crests 3 – 4 (Fig 18). The original description of Chthamalus panamensis Pilsbry, 1916, (pp. 219 – 320 and Plate 75 fig 2, 2 a, 2 b, 2 c, 2 d and 2 e) describes only the shell and opercular plates (also see Fig 18 B). Pilsbry’ s figure of the exterior of the tergum (Plate 75 fig 2 e) is closely similar to the exterior of terga in our new material. The following description of the arthropodal characters is based on new material [Avenida Amador, Naos Island]. Quantitative data on segments counts in cirrus I-III were based on five specimens collected from Avenida Amador, Naos Island (PWG- 1). Segment counts on cirri IV-VI were based on a single specimen from Avenida Amador, Naos Island (PWG- 1) (Table 4). Cirrus I: posterior ramus 5 - to 7 - segmented, anterior ramus 6 - to 8 - segmented, outer surface with a longitudinal array of long setae, with almost one seta per segment, serrulate setae common on both rami (Figs 19 A and 19 B and 20 A – 20 D). Cirrus I without bidenticulate setae (absent from all specimens examined), pappose setae on basipodite (Fig 20 E). Cirrus II: posterior ramus 5 to 7 segments, anterior ramus 6 to 8 segments (Figs 19 C and 20 G), the most distal segment of each ramus with bidenticulate setae with basal guards, serrulate setae common on both rami (Figs 19 C and 19 D and 20 G – 20 I, Table 4). Pappose setae on basipodite (Fig 20 J and 20 K). Cirrus III: posterior 12 - to 16 - segmented, anterior ramus 16 - to 22 - segmented, 1.4 to 1.5 times the length of the anterior ramus (Fig 19 E), intermediate segments bear 3 pairs of long and 1 pair of short setae (Figs 19 E and 20 L – 20 N). Cirrus IV: anterior and posterior rami similar in length (Fig 19 F), anterior and posterior rami 16 segmented (Figs 19 F and 20 O and 20 P). Cirrus V: anterior and posterior rami 16 - segmented (Fig 19 G). Cirrus VI: anterior ramus 19 - segmented, posterior ramus 20 - segmented (Figs 19 H and 20 Q). The intermediate segments of cirri IV-VI bear three pairs of long and one or two pairs of short simple setae (Figs 19 F – 19 H and 20 S and 20 R). Maxilla bilobed, with dense serrulate setae on each lobe (Figs 21 A and 22 A – 22 C). Maxillule notched, notch weak, two large setae above notch, 10 setae below notch (Figs 21 B and 22 D and 22 E). Mandible has 4 major teeth, second to fourth teeth bidenticulate, pecten with 21 very small teeth, inferior angle tipped with 3 pointed teeth (Figs 21 C and 21 D and 22 F – 22 K). Mandibular palp rectangular, with long simple setae on tip and serrulate setae on superior margin (Figs 21 E and 21 F and 22 L, 22 M and 22 N). Labrum concave, with 6 or 7 small fine teeth on cutting edge (Figs 21 G and 21 H and 22 O and 22 P). Penis without basi-dorsal point.	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6317842CC77949DE0A34FE20.taxon	distribution	Distribution. Pacific coast of Central America from about 14 ° N to 8 ° 15 ' N (southern limit unknown).	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
03D887BE6317842CC77949DE0A34FE20.taxon	discussion	Remarks. Specimens of C. panamensis collected for the present study agreed with the syntypes of C. panamensis described by Pilsbry [2] in having a deep groove on the outer surface of the tergum, which is the key diagnostic feature of C. panamensis. This morphological feature of the tergum was also reported in Pitombo & Burton [12]. The sympatric C. newmani sp. nov is distinguishable from C. panamensis in situ by its lack of deep tergal grooves. In addition, it has has brown tergo-scutal flaps while those of C. panamensis are orange. The flaps are visible in the living barnacle when the orifice is open under water (Fig 2 E and 2 F). Arthropodal character differences are: Cirrus I of C. newmani has bidenticulate setae, Cirrus I of C. panamensis does not. Cirrus III of C. newmani has equal rami. Cirrus III of C. panamensis has unequal rami. This feature of cirrus III in C. panamensis was not reported by Pilsbry [2] or Pitombo & Burton [12].	en	Benny K. K. Chan, H. - N. Chen, P. R. Dando, A. J. Southward, E. C. Southward (2016): Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia). PLoS ONE 11 (3): 1-51, DOI: 10.1371/journal.pone.0149556
