Caridina moeri Woltereck, 1984

Richard, Jasmine & Clark, Paul F., 2010, Caridina H. Milne Edwards, 1837 (Crustacea: Decapoda: Caridea: Atyoidea: Atyidae) - freshwater shrimps from eastern and southern Africa *, Zootaxa 2372 (1), pp. 305-337 : 325-328

Caridina moeri Woltereck, 1984

( Figs. 10–11 )

Caridina indistincta — Woltereck 1942: 290–293.

Caridina ? indistincta . — Barnard, 1950: 660–661.

Caridina moeri Woltereck, 1984: 102–120 , figs. 1, 2, 3.

Material examined. (Non types). Zimbabwe Garden Bay , Ume River, Near Shore of Lake Kariba, coll. Dr Kelly 19– 20.9.2003, OUMNH-ZC.2007-03-001, 4 males , 5 ov. females, 2 females; det. J. Richard; same data, pres. S. De Grave, NHM 2007.789–798, 7 males , 5 ov. females, 3 females; Zambesi River , 16.6.1916, coll. G. Arnold, SAM A 4051 , 1 male, 1 female , 1 cephalothorax.

Comparative material of Caridina indistincta Calman, 1926 : Syntypes, Australia, St. George District , Queensland, coll. Wilkin’s Australia & Ids. Expedition, NHM 1924.12.22.69–76, 3 males, 3 females, plus a number of dissected specimens. The male with a rostral formula of (3) 24/6 is here selected as the lectotype and the remaining specimens are considered as paralectotypes.

Description. Total length: 25–35 mm. Carapace length: 4.5–5.5 mm.

Rostrum ( Figs. 10a–c ): equal to, or longer than antennal scale, 5.5–6.5 mm long and is 1.2–1.5 as long as carapace. 25–48 teeth extending to tip on dorsal margin. 2–4 post orbital teeth. 7–23 teeth on ventral margin extending almost to tip or leaving short distal part unarmed. Tip pointed. Formula (2–4) 25–48/7–23.

Antennular peduncle ( Fig. 10d ): 0.7–0.8 as long as carapace. Stylocerite 0.6–0.7 times length of basal segment. Anterolateral teeth of basal segment 0.20–0.25 as long as second segment. 6–17 segments bearing aesthetascs.

First pereiopod ( Fig. 11a ): dactylus 0.9–1.0 as long as palm of propodus. Chela 2.5–2.8 as long as wide. Carpus 2.0–2.5 as long as wide with anterior excavation.

Second pereiopod ( Fig. 11b ): long and slender. Dactylus 1.2–1.4 as long as palm of propodus. Chela 3.5– 4 as long as wide. Carpus 5.5–6.5 as long as wide. Bristle-like setae at tip of chelae of first and second pereiopods.

Third pereiopod ( Figs. 11c–d ): dactylus 2.9–3.5 as long as wide. 6–9 spines on dactylus (including terminal spines). Propodus 4–5 as long as dactylus and 11–12 as long as wide with 9–14 spines along inner margin. Carpus 0.5–0.6 as long as propodus with minute spines on inner margin. Merus 1.6–2 of carpus length with 2 large spines on posterior margin.

Fifth pereiopod ( Figs. 11e–f ): dactylus 3.5–4 as long as wide with 45–60 spines in comb-like arrangement on inner margin. Propodus 12.5–14 as long as wide and 3.5–4 as long as dactylus with 9–12 spines arranged along posterior margin. Carpus 0.45–0.6 of propodus length with minute spines along inner margin. Merus 1.5–1.7 of carpus length with 2 large spines at posterior margin.

Setobranch: 2 setae on each pereiopod.

First male pleopod ( Figs. 11g, h ): endopod 0.25–3 of exopod length. Appendix interna absent.

First female pleopod ( Fig. 11i ): endopod 0.4–0.6 as long as exopod.

Eggs ( Fig. 10j ): 135–150, 0.6–0.8 × 0.4–0.5 mm in size.

Second male pleopod ( Figs. 11k–m ): appendix masculina 1.0–1.4 as long as appendix interna and 0.25– 0.4 length of endopod. Male from Zambesi River (SAM A 4051) has shorter appendix masculina with few long spines. Males from Ume River have longer appendix masculina with shorter spines.

Sixth abdominal somite: 0.6–0.7 × long as carapace.

Telson ( Figs. 11n–o ): 0.9–1 as long as 6 th abdominal somite. Tapering distally, posterior margin triangular with median point or rounded. Dorsal spines 4–6 pairs (including subterminal spine). 1 pair of lateral spines and 4–5 pairs or 7 to 9 short spines of equal length present at triangular posterior margin.

Uropod ( Fig. 11p ): 7–10 diaeresis spinules.

Preanal carina ( Fig. 11q ): unarmed.

Distribution. Democratic Republic of Congo, Zimbabwe.

Remarks. Initially Woltereck (1942) identified Caridina indistincta Calman 1926 (type locality St. George District, Queensland, Australia) and described her material from 16 sites around Lake Moero, Belgian Congo, now Democratic Republic of Congo. Later Woltereck (1984) borrowed specimens of C. indistincta from the Australian Museum and realised that her material from Lake Moero was a new species. Caridina moeri can be distinguished from C. indistincta by possessing a rostrum that is longer than or equal to the antennal scale (vs. rostrum equal to antennal scale or shorter, never longer), 25–48 teeth on the dorsal margin of the rostrum (vs. 20–33 teeth) and 7–23 teeth on the ventral margin of the rostrum (vs. 3–7 teeth). The figures of C. moeri in Woltereck (1984: fig. 1, 2) and her description, clarify the identification of this species. However she did not figure many characters and for this reason C. moeri is redescribed and fully figured in the present study.

Barnard (1950: 660–661) followed Woltereck (1942) by identifying Caridina ? indistincta Calman 1926 from the Zambesi River, collected by Dr G. Arnold. This material was examined in the present study and compares well with C. moeri .

Figures

FIGURE 10. Caridina moeri Woltereck, 1984, NHM 2007.789–798, ov. female: a, habitus; b, anterior region of cephalothorax. SAM 4051, male: c, anterior region of cephalothorax. NHM 2007.789–798, ov. female: d, antennular peduncle.

FIGURE 11. Caridina moeri Woltereck, 1984, NHM 2007.789–798, ov. female: a, first pereiopod; b, second pereiopod; c, third pereiopod; d, dactylus of third pereiopod; e, fifth pereiopod; f, dactylus of fifth pereiopod; g, first male pleopod; h, endopod of the first male pleopod; i, first male pleopod; j, egg; k, second male pleopod; l, appendix masculina. SAM 4051, male: m, appendix masculina. NHM 2007.789–798, ov. female: n, telson; o, posterior margin of telson; p, uropod diaeresis spinules; q, preanal carina.