Caridina coulaborensis, Richard, Jasmine & Clark, Paul F., 2014

Richard, Jasmine & Clark, Paul F., 2014, Caridina simoni Bouvier, 1904 (Crustacea: Decapoda: Caridea: Atyoidea: Atyidae) and the synonymy by Johnson, 1963, Zootaxa 3841 (3), pp. 301-338 : 324-326

Caridina coulaborensis sp. nov.

( Fig. 13 )

Material examined. Caridina meridionalis . Types: Holotype. Cotype. New Caledonia. Coula-Boréaré, coll. F. Sarasin & J. Roux, 6.2.12 (another label, Drs. F. Sarasin & J. Roux, Coula Fluss bei Boréaré, 6.II.12) NMB reg. 4.VIII.e, 1♂; Paratypes. Cotypes. Coula-Boréaré, coll. F. Sarasin & J. Roux, 6.2.12 (another label, Drs. F. Sarasin & J. Roux, Coula Fluss bei Boréaré, 6.II.12) NMB reg. 4.VIII.e, 11♂, 4♀ ovig., 11♀; Tiouaka Tal, coll. F. Sarasin & J. Roux, 20.8.11 (another label, Drs. F. Sarasin & J. Roux, Mune Tiouaka 20 avec C. sp.) NMB reg. 4.VIII.c, 5♂, 1♀ ovig., 6♀, 3 damaged specimens; Koné, coll. F Sarasin & J. Roux, 9.8.1911 NMB reg. 4.VIII. d 8♂, 4♀ ovig., 3♀; Lao Foa , 16.1.12, NMB reg. 4.VIII.f 16♂, 7♀ ovig., 5♀; Coindé 12.1.12, NMB reg. 4.VIII.g, 3♂; ZW Nouméa & Païta , III.11, coll. F. Sarasin & J. Roux, NMB reg. 4.VIII.h, 1♀ ovig.

Description. From male holotype and paraptypes. Adult size 23–35 mm. Carapace length 3.0– 4.5 mm

Rostrum ( Fig. 13 a): Length variable reaching antennal scale or fractionally longer or as shorter as middle of third antennular peduncle segment. Rostrum 2.5–4.5 mm 0.8–1.0×long as carapace 11–22 teeth proximally on dorsal margin leaving 0.3–0.45 of the dorsal margin unarmed distally. 1–2 post orbital teeth. Tip bifid. 7–17 teeth from the proximal end to the tip or with a short distal unarmed end on the ventral margin. Formula (1–2) 11–22/ 7–17.

Antennular peduncle ( Fig. 13 a): 0.6–0.75×carapace. Stylocerite 0.5–0.7×length of basal segment. Anterolateral teeth of basal segment 0.15–0.25×second segment. 9–12 segments bearing aesthetascs.

First pereiopod ( Fig. 13 b): Dactylus 1.2–1.4×palm of propodus. Chela 1.9–2.3×long as broad. Carpus 1.8–2.4×long as broad, with the anterior excavation.

Second pereiopod ( Fig. 13 c): Dactylus 1.2–1.4×long as palm of propodus. Chela 2.8–3.0×long as broad. Carpus 4.5–5.5×long as broad.

Third pereiopod ( Fig. 13 d, e): Dactylus 2.0–2.3×long as broad. 6–11 spines on dactylus (including terminal spines). Propodus 6.0–7.0×long as dactylus and 12–14×long as broad with 9–14 spines arranged along inner margin. Carpus 0.55–0.65×long as propodus, with 1 large spine and 2–5small spines on inner margin. Merus 1.5–1.8×carpus length. Merus with 3 large spines along posterior margin.

Fifth pereiopod ( Fig. 13 f, g): Dactylus 3.7–5.0×long as broad with 45–60 spines arranged in comb-like fashion on inner margin. Propodus 14–16×long as broad and 4.5–5.5×long as dactylus with 10–15 spines arranged along posterior margin. Carpus 0.45–0.6×propodus length and with one large spine and 3–6 minute spines along inner margin. Merus 1.5–1.9×carpus length, with 3 large spines along posterior margin.

Setobranch: With two setae on all pereiopods.

First male pleopod ( Fig. 13 h): Endopod 0.45–0.50×exopod length; appendix interna present.

First female pleopod: Endopod 0.45–0.6×long as exopod.

Eggs ( Fig. 13 i): ca. 95 eggs of 0.6–0.65× 0.35–0.43 mm size.

Second male pleopod: appendix masculina 1.7–2.0×appendix interna, 0.4×endopod.

6th abdominal somite: 0.5–0.7×long as carapace.

Telson ( Fig. 13 j–l): 1.0–1.1×long as 6th abdominal somite. 4–7 pairs of dorsal spines (including subterminal spines). Posterior margin exhibits variations. It is mostly rounded without a median process rarely triangular with a median process. In specimens from Tiouaka (NMB 4VIII c), the telson tip is much broader in the females ( Fig. 13 k) and comparatively narrower in the males ( Fig. 13 l). 1 pair of lateral spines and 2–3 pairs of intermediate spines present. The intermediate spines are either slightly shorter, equal to or fractionally longer than the lateral spines.

Uropod: 9–14 diaeresis spinules.

Anal carina: Armed with a spine.

Etymology. coulaborensis : named for the type locality in New Caledonia being an abitory combination of Coula-Boréaré.

Distribution. New Caledonia.

Type locality. Coula-Boréaré, New Caledonia.

Remarks. The specimens described by Roux as C. meridionalis from Coula-Boréaré, Tiouaka Tal, Koné, Lao Foa, Coindé, SW Nouméa & Païta, New Caledonia were considered to be an undescribed species, named here as Caridina coulaborensis sp. nov.

Caridina coulaborensis sp. nov. differs from C. n. meridionalis in having a rostrum with 11–22 teeth proximally on the dorsal margin leaving 0.3–0.45 unarmed distally (vs. 19–27 teeth on the dorsal margin to the tip in C. n. meridionalis ), tip of the rostrum bifid (vs. mostly tip pointed, rarely bifid in C. meridionalis ), ventral margin of rostrum with 7–17 teeth (vs. 4–10 teeth in C. n. meridionalis ) and posterior margin of the telson mostly rounded rarely triangular with 2–3 pairs of intermediate spines that are either slightly shorter, equal to or fractionally longer than the lateral spines (vs. triangular posterior margin converging to a median pointed process with 2 pairs of intermediate spines that are slightly shorter than the lateral spines in C. n. meridionalis ).

The proximal placement of teeth on the dorsal margin of the rostrum with a distal unarmed end in the new species is similar to that described for Caridina nilotica (see Richard & Clark 2005), but it differs in having a rounded or triangular posterior margin of the telson with long spines (vs. the posterior margin of the telson being almost flat and not protruding with 1–3 pairs of short stout spines present in C. nilotica ). Caridina coulaborensis sp. nov. differs from C. brachydactyla in having a rounded posterior margin of telson with or without a median process (vs. triangular posterior margin always ending in a median process in C. brachydactyla ) and ca. 95 large eggs of 0.6–0.65× 0.35–0.43 mm size (vs. ca. 850 small eggs 0.35–0.41× 0.2–0.23 mm in C. brachydactyla ).

Caridina coulaborensis sp. nov. differs distinctly from C. simoni in possessing 11–22 teeth proximally on the dorsal margin of rostrum leaving 0.3–0.45 of the dorsal margin unarmed distally (vs. 15–25 proximal teeth leaving distally 0.25–0.4 unarmed or interrupted by 1–4 teeth in C. simoni ), tip of rostrum bifid (vs. tip pointed in C. simoni ), ventral margin of rostrum with 7–17 teeth proximally to the tip or with a short distally unarmed margin (vs. with 5–14 teeth proximally leaving the distal ventral margin always unarmed in C. simoni ) and in having comparatively smaller eggs of 0.6–0.65× 0.35–0.43 mm size (vs. 0.65–1.0× 0.45–0.6 mm in C. simoni ).

Figures

FIGURE 13. Caridina coulaborensis sp. nov. Holotype NMB 4. VIII. e, ♂: a) Anterior region of the cepahalothorax; b) First pereiopod; c) Second pereiopod; d) Third pereiopod; e) Dactylus of third pereiopod; f) Fifth pereiopod; g) Dactylus of fifth pereiopod; h) Endopod of first male pleopod; Paratypes ♀ ovig.: i) Egg; j) Posterior margin of telson; NMB 4. VIIIc ♀: k) Posterior margin of telson; Holotype ♂: l) Posterior margin of telson.