Caridina evae, Richard & Clark, 2009

Jasmine Richard & Paul F. Clark, 2009, African Caridina (Crustacea: Decapoda: Caridea: Atyidae): redescriptions of C. africana Kingsley, 1882, C. togoensis Hilgendorf, 1893, C. natalensis Bouvier, 1925 and C. roubaudi Bouvier, 1925 with descriptions of 14 new species, Zootaxa 1995, pp. 1-75 : 28-32

Caridina evae sp. nov.

( Figs. 11 , 12 , 13 )

aterial examined. Holotype: ♂ Nigeria, Chubra division, S. Nigeria, pres. I. Sanderson, NHM 1938.7.1.47. Paratypes: Sierra Leone coll. & pres. Dr. D. J. Lewis, NHM 1956.6.1.2–6, 1) Farangbaia, 29.11.55, 1♀ ovig., 2) Farangbaia, 14.12.1955, 1♀ ovig, 3) Sahesachala, 28.10.55, 3♂. Liberia Gwinney Creek, Tchien near border with Ivory Coast, ca. 100 miles inshore, 5.2.1967, small, shallow, slow flowing stream with lots of leaf litter, Chura leg. T. C. Rutherford, RMNH D 24468, 1♂. Nigeria 23.6.33, pres. I. Sanderson, NHM 1938.7.1.48–52, 6♂, 2♀ ovig., 1♀; Cameroon 27.3.33, No 155 in Bashor II Mamfe Div. Cameroons, 650 feet, pres. I. Sanderson, NHM 1938.7.1.41–44, 1♂, 1♀ ovig., 4♀; Mamfe Div. Cameroons 9.5.35, No 272 in Mainyu Bridge marfioeo, Cameroon, 500–600 feet, pres. I. Sanderson, NHM 1938.7.1.45–46, 1♂, 1♀; Black waters, coll. (27) 3.12.68, R. H. L. Disney, NHM 1974.696, 1♂, 1♀ ovig., 2♀; Black waters, 7.1.69, coll. R. H. L. Disney, NHM 1974.697, 1♀; Menge River, (186), coll. R. H. L. Disney, 8.3.69, NHM 1974.698, 1♂, 1♀; Okia stream, coll. R. H. L. Disney, 14.11.68, NHM 1974.699, 12♂, 5♀ ovig., 23♀; Kobe let, coll. R. H. L. Disney, 6.11.70, NHM 1974.700, 1♀; Ikilinindli, coll. R. H. L. Disney, 7.11.70, NHM 1974.701, 2♂, 1♀ ovig.; Black waters, 2.12.69, coll. R. H. L. Disney, NHM 1974. 702, 11♂, 6♀ ovig., 19♀; Mongusu Stream, coll. R. H. L. Disney, 14.11.68, NHM 1974.703, 6♂, 3♀; Okia, coll. R. H. L. Disney, 10.11.70, NHM 1974.704, 4♂, 2♀ ovig., 2♀; Kobe river Etam, coll. R. H. L. Disney, NHM 1974.705, 2♀ ovig. Gabon Keri, Gabon, W. Africa, Forest stream 20 km North of Lambarene, 15.11.1984, NHM 2007.724–729, 4♀.

Description. Total length: 14–25 mm. Carapace length: 4–5 mm.

Rostrum ( Fig. 11 a-e): short, straight, shorter or equal to, or slightly longer than antennular peduncle. 5– 2.9 mm in length. 0.30 to 0.65 × carapace. 3–12 (mostly 6–12) teeth on dorsal margin leaving 0.4–0.75 of length distally unarmed. 3–6 (mostly 3–5) post-orbital teeth. 1–5 teeth arranged on distal ventral margin below dorsal unarmed margin to tip or with short distal end unarmed. Tip pointed. Formula (3–6) 3–12/1–5 mostly (3–5) 6–12/2–5.

Antennular peduncle ( Fig. 11f ): antennular peduncle 0.7 × carapace. Basal segment of antennular peduncle with long stylocerite reaching 0.9–1.1 × basal segment. Anterolateral teeth of basal segment short being 0.08–0.15 × second segment. Aesthatasc bearing segments 6–10.

First pereiopod ( Fig. 12a ): dactylus 0.9–1.3 × palm of propodus. Chela, 2.0–2.3 × long as broad. Carpus slender 1.8–2.1 × long as broad. Carpus with deep excavation anteriorly.

Second pereiopod ( Fig. 12b ): Long and slender. Dactylus 1.1–1.3 × long as palm of propodus. Chela 2.9–3.2 × long as broad. Slender carpus 4.5–5.5 × long as broad.

Bristle-like setae arranged at tip of chelae of first and second pereiopods.

Third pereiopod ( Fig. 12c, d ): dactylus 2.25–2.6 × long as broad with 5 to 7 spines (including terminal spine). Propodus 3.8 to 4.5 × long as dactylus and 8–10 × long as broad with 9–15 small spines arranged along posterior margin. Carpus 0.6–0.8 × propodus and with small spines on inner margin, merus with 4–5 big spines on posterior margin and 1.6 to 1.7 × carpus.

Fifth pereiopod ( Fig. 12e, f ): dactylus 3.0–4.2 × long as broad with 65–80 spines arranged in comb-like fashion on posterior margin. Propodus 3.0–3.5 × long as dactylus and 10–11 × long as broad. Carpus 0.5–0.7 × propodus with small spines on posterior margin. Merus 1.4–1.6 × carpus and with 3 large spines on posterior margin.

Setobranchs: 3 on all pereiopods.

First male pleopod ( Fig. 12g, h ): endopod 0.6–0.8 × exopod, with short appendix interna. Endopod with closely arranged long stalked setae on outer margin and with shorter setae on inner margin.

First female pleopod ( Fig. 12i, j ): almost equal in length to exopod 0.8–1.00 × exopod.

Eggs ( Fig. 12k ): 20–25, 1.1–1.3 × 0.6–0.75 mm in size.

Second male pleopod ( Fig. 13a, b ): Appendix masculina 1.9–2 × appendix interna and 0.37–0.45 × exopod.

Sixth abdominal segment: 0.35–0.6 × long as carapace.

Telson ( Fig. 13c, d ): 1–1.25 × long as sixth segment, broad and robust. Fine setae present on telson, 5–7 pairs of dorsal spines (including subterminal spines) arranged in curved fashion.1 plain lateral spine and 4 or 5 pairs of long densely plumose stalked processes present on rounded posterior margin. Short, fine setae attached to posterior margin between plumose processes.

Uropod ( Fig. 13e, f ): 17–21 diaeresis spinules.

Preanal carina ( Fig. 13g ): shaped like protruding peg without spines and adorned with long setae.

Remarks. Caridina evae sp. nov. is distinct by virture of having fewer teeth on the dorsal margin of the rostrum arranged at the proximal end leaving the distal dorsal margin unarmed and with 3 or 4 post-orbital teeth. The teeth on the ventral margin are always arranged at the distal end beginning from the point where the dorsal teeth end. The rostral formula is (3–6) 3–12/1–5, mostly (3–5) 6–12/2–5. The tip of the rostrum is always pointed. The stylocerite is long, reaching 0.9–1.1 of the first segment of the antennular segment. The anterolateral tooth is shorter, reaching 0.08–0.15 × the second segment. The endopods of the first pleopods of male longer with a shorter appendix interna and the endopod of the first pleopod of female is longer. The appendix masculina is longer. There are 20–25 larger eggs. The telson is broad. There are 17–21 spinules on the uropod diaeresis and the preanal carina is peg-like and without spines. All these characters make C. evae sp. nov. distinct from C. africana and C. togoensis . However, in possessing the long, stalked, plumose processes on the posterior margin of the telson, C. evae sp. nov. is similar to C. togoensis .

Etymology. Caridina evae is named for Dr.Eva Roth-Woltereck, in appreciation of her contributions to the study of Crustacea, especially the atyid fauna of Africa.

Figures

FIGURE 11. Caridina evae sp. nov., NHM 1938.7.48–52, ♂: a) Entire. NHM 1974.704, ♂: b) Anterior region of cephalothorax. NHM 1974.704, ♂: c) Anterior region of cephalothorax. RMNH D 24468, ♂: d); Anterior region of cephalothorax. NHM 1974.699, ♂: e) Anterior region of cephalothorax; f) Antennular peduncle.

FIGURE 12. Caridina evae sp. nov., NHM 1938.7.48–52, ♂: a) First pereiopod; b) Second pereiopod; c) Third pereiopod; d) Dactylus of third pereiopod; e) Fifth pereiopod; f) Dactylus of fifth pereiopod; g) First pleopod; h) Endopod of first pleopod. ♀ ovig.: i) First pleopod; j) First pleopod; k) Eggs.

FIGURE 13. Caridina evae sp. nov., NHM 1938.7.48–52, ♂: a) Second pleopod; b) appendix masculina; c) Telson; d) Posterior margin of telson; e) Uropod; f) Uropod diaeresis spinules; g) Preanal carina.