Caridina rintelenorum, Mazancourt & Marquet & Keith, 2024

Mazancourt, Valentin de, Marquet, Gérard & Keith, Philippe, 2024, An Integrative Taxonomic Revision of the Freshwater Atyid Shrimps (Crustacea: Decapoda: Caridea) of Micronesia, Diversity 16 (200), pp. 1-31 : 19-21

Caridina rintelenorum sp. nov.

urn:lsid:zoobank.org:act:FF389D46-B517-4D59-9102-34638B8B62C2

Figures 3G , 8 and 9D .

Material examined

Type material

PALAU: Babeldaob Island . Holotype: MNHN-IU-2024-462 (DNA: CA1864 ): 1 ♀ ovig. cl 3.3 mm, Ngardmau river , waterfall, 07 ◦ 35.482 ′ N, 134 ◦ 35.573 ′ E, 2 March 2011, coll. M. Castelin, P. Gerbeaux, P. Keith, G. Marquet, and L. Taillebois.

Paratypes: RMNH.CRUS.D.16641 : 1 ♀ ovig. cl 2.9 mm, stn. 122, Luhet river , Ollei village , Ngarchelong peninsula , 23 August 1955, coll. A. Fehlmann, George Vanderbilt Foundation; USNM 105450 : 1 ♀ ovig., cl 3.0 mm and 1 juv. cl 2.0 mm, Station 122 , 7 ◦ 42.888 ′ N, 134 ◦ 37.383 ′ E, 23 August 1955, coll. F.M. Bayer. USNM 172595 : 1 ♂ cl 2.2 mm, 1 ♀ ovig. cl 2.6 mm and 1 juv. cl 1.9 mm, Ngerbekuu river , station 1NBK 4-12 , 1 June 1978, coll. G. Bright. USNM 172596 : 1 ♀ ovig. cl 2.7 mm, Ngerbekuu river , station 1NBK 4-11 , 1 June 1978, coll. G. Bright.

SOLOMON ISLANDS. Isabel Island . MNHN-IU-2024-463 (DNA voucher: CA2534 ): 1 ♀ ovig. cl 2.9 mm, Hobolito river , 7 ◦ 37.510 ′ S, 158 ◦ 32.434 ′ E, 24 October 2019, coll. R. Causse, P. Keith, and C. Lord .

Comparative material

Caridina celebensis . INDONESIA. Paralectotype (lectotype designated in [51]), MNHN- IU-2015-1926: 1 ♀ ovig. cl 3.5 mm, Sulawesi, Luwu, river near Palopo, February 1889, coll. M. Weber. SOLOMON ISLANDS: Kolombangara Island . MNHN-IU-2018-2941 : 1 ♀ ovig. cl 3.1 mm, Lodumoe river , 07 ◦ 50.961 ′ S, 157 ◦ 04.320 ′ E, 16 November 2015, coll. P. Keith, C. Lord , and G. Marquet. MNHN-IU-2018-2942 : 1 ♀ ovig. cl 3.2 mm, same collection data as for preceding. MNHN-IU-2018-2943 (DNA: CA1518 ): 1 ♀ cl 3.5 mm, Munga river , 07 ◦ 54.420 ′ S, 156 ◦ 57.932 ′ E, 5 ma.s.l., 19 November 2015, coll. P. Keith, C. Lord , and G. Marquet. MNHN-IU-2018-2944 : 1 ♀ ovig. cl 3.4 mm, Liva river , 08 ◦ 03.863 ′ S, 157 ◦ 10.633 ′ E, 14 m a.s.l., 11 November 2015, coll. P. Keith, C. Lord and G. Marquet. Vella Lavella Island . MNHN-IU-2018-2945 : 1 ♀ ovig. cl 3.5 mm, Wariassi river , 29 October 2016, coll. P. Keith, and C. Lord . VANUATU: Efate Island . MNHN-IU-2018-2946 (DNA: CA1381 ): 1 ♀ cl 3.0 mm, Marona river , 17 ◦ 33 ′ 51.860 ′′ S, 168 ◦ 17 ′ 08.140 ′′ E, 5 m a.s.l., 9 November 2014, coll. A. Acou, G. Marquet, and M. Mennesson. MNHN-IU-2018-2947 : 1 ♀ ovig. cl 3.4 mm, Mele river , 17 ◦ 40.578 ′ S, 168 ◦ 15.462 ′ E, 9 November 2014, 32 ma.s.l., coll. A. Acou, G. Marquet and M. Mennesson.

Description

Cephalothorax. Antennal spine ventral to inferior orbital angle. Pterygostomian margin rounded. Rostrum ( Figure 8k ): straight, 0.5–0.6 times length of cl, reaching to base of third segment of antennular peduncle, armed with 19–21 teeth on dorsal margin, 7–10 of them situated on carapace behind orbital margin, ventral margin with 5–8 teeth. Eyes developed, anterior end reaching to 0.65 times length of basal segment of antennular peduncle. Long antennular peduncle, 0.69 (♀) times as longas carapace. Second segment distinctly longer than third segment. Long stylocerite reaching beyond end of first segment of antennular peduncle.

Pereiopods. Epipods on first four pereiopods. P1 ( Figure 8a ): chela about 2.1–3.1 times as long as wide, movable finger 2.5–5.2 times as long as wide, 0.9–1.6 times length of palm; carpus 3.4–4.9 times as longas wide. P2 ( Figure 8b ) more slender and longer than first pereiopod, with chela 5.0–6.1 times as long as wide: movable finger 6.2–7.0 times as long as wide, 1.3–1.4 times length of palm; carpus slender, 8.0–12.3 times as longas wide. P3 ( Figure 8c ): slender, dactylus ( Figure 8e ) 3.7–4.0 times as long as wide (terminal spiniform seta included), with 6-9 spiniform setae on flexor margin including terminal one; propodus 12.1–14.1 times as long as wide, 3.8–4.5 times as long as dactylus. P5 ( Figure 8d ): dactylus ( Figure 8f ) 3.7–4.5 as long as wide, with 7–13 spiniform setae on flexor margin; propodus 15.5–17.4 times as long as wide, 4.1 times as long as dactylus.

Abdomen. Third abdominal somite with moderately convex dorsal profile. Sixth abdominal somite 0.45 times as long as carapace, 1.6 times as long as fifth somite, shorter than telson.

Telson ( Figure 8h ). 2.4 times as long as wide, with four pairs of dorsal spinules and one pair of dorsolateral spinules; posterior margin with a median process, rounded, with 7–12 very long intermediate plumose setae longer than lateral ones.

Male pleopods. No males.

Pre-anal carina ( Figure 8i ). High, with a spine.

Uropodal diaeresis ( Figure 8g ). With 14–19 spinules.

Eggs ( Figure 8j ). Size: 0.34–0.41 mm × 0.19–0.24 mm.

Habitat

This new species occurs in the lower to middle course of the rivers, sometimes in slightly brackish conditions.

Etymology

C. rintelenorum sp. nov. is named in honor of Kristina and Thomas von Rintelen (Museum für Naturkunde, Berlin, Germany) as an acknowledgement to their continuous support for the research of the first author and their years of study of atyid shrimps from South-East Asia.

Colour pattern

Body ( Figure 8d ) with more or less wide transverse bands of whitish, brownish, or dark color. Pereiopods with alternating bands of light and dark color.

Distribution

This species occurs in Palau and Solomon Islands (Isabel Island) and is expected to have a wider distribution in the region.

Remarks

This species is more similar to C. celebensis than to C. serratirostris by its shorter rostrum reaching to the base of the third segment of the antennular peduncle (vs. reaching beyond the end of the antennular peduncle), with fewer dorsal teeth, 19–21 (vs. 22–26); its longer P2 carpus, 8.0–12.3 as long as wide (vs. 8.3–10.9), and P2 chela 5.0-6.1 times as long as wide (vs. 3.7–5.1), but its shorter movable finger 1.3–1.4 times the length of the palm (vs. 1.7–1.9) and P5 propodus 15.5–17.4 times as long as wide (vs. 18.7–24.0) and 4.1 times as long as the dactylus (vs. 4.5–5.5).

This new species differs from C. celebensis by its shorter rostrum, being 0.5–0.6 times length of cl (vs. 0.6–0.9), and by its P5 propodus 4.1 times as longas the dactylus (vs. 3.4–3.9).

Figures

Figure 3. Phylogenetic tree of the atyid species from Micronesia obtained by Bayesian inference from the 16S rRNA. Numbers above branches indicate Bayesian posterior probabilities, numbers under branches indicate maximum likelihood bootstraps. Letters A–K for the clades refer to the species listed in the taxonomic account.

Figure 8. Caridina rintelenorum sp. nov. (a) first pereiopod; (b) second pereiopod; (c) third pereiopod; (d) fifth pereiopod; (e) dactylus of third pereiopod; (f) dactylus of fifth pereiopod; (g) uropodal diaeresis; (h) telson; (i) pre-anal carina; (j) undeveloped eggs; (k) cephalothorax. Holotype: MNHN- IU-2024-462 (DNA: CA1864): a–g and i–k. Paratype: MNHN-IU-2024-463 (DNA: CA2534): h.

Figure 9. Coloration in life. (A) Atyopsis spinipes from Pohnpei (P. Keith); (B) Atyoida chacei sp. nov. from Palau (H. Ketebengang, inaturalist.org); (C) Caridina ponapensis sp. nov. from Pohnpei (P. Gerbeaux); (D) Caridina rintelenorum sp. nov., paratype MNHN-IU-2024-463 from Isabel, Solomon Islands (P. Keith).