Caridina celebensis De Man, 1892

Mazancourt, Valentin de, Boseto, David, Marquet, Gerard & Keith, Philippe, 2020, Solomon’s Gold Mine: Description or redescription of 24 species of Caridina (Crustacea: Decapoda: Atyidae) freshwater shrimps from the Solomon Islands, including 11 new species, European Journal of Taxonomy 696, pp. 1-86 : 71-79

Caridina celebensis De Man, 1892

Figs 2B , 24

Caridina serratirostris var. celebensis De Man, 1892: 385 , pl. 23, figs 28f–h (type locality: river at Palopo, Luwu, Sulawesi (Celebes), Indonesia).

Caridina serratirostris var. celebensis – Bouvier 1925: 220.

Caridina celebensis – Holthuis 1978: 39, fig. 14. — Cai & Shokita 2006b: 247 . — von Rintelen et al. 2012 (GenBank: FN995356 ).

Material examined

Paralectotype (lectotype designated in Cai & Shokita 2006b) INDONESIA • 1 ♀ ovig., cl 3.5 mm; Sulawesi, Luwu, river near Palopo ; Feb. 1889; M. Weber leg.; MNHN-IU-2015-1926 .

Other material

SOLOMON ISLANDS – Kolombangara Island • 1 ♀ ovig., cl 3.1 mm; Lodumoe River ; 07°50.961´S, 157°04.320´E; 16 Nov. 2015; P. Keith, C. Lord and G. Marquet leg.; MNHN-IU-2018-2941 • 1 ♀ ovig., cl 3.2 mm; same collection data as for preceding; MNHN-IU-2018-2942 • 1 ♀, cl 3.5 mm; Munga River ; 07°54.420´S, 156°57.932´E; 5 m a.s.l.; 19 Nov. 2015; P. Keith, C. Lord and G. Marquet leg.; DNA voucher: CA1518; MNHN-IU-2018-2943 • 1 ♀ ovig., cl 3.4 mm; Liva River ; 08°03.863´S, 157°10.633´E; 14 m a.s.l.; 11 Nov. 2015; P. Keith, C. Lord and G. Marquet leg.; MNHN-IU-2018-2944 . – Vella Lavella Island • 1 ♀ ovig., cl 3.5 mm; Wariassi River ; 29 Oct. 2016; P. Keith and C. Lord leg.; MNHN-IU-2018-2945 .

VANUATU – Efate Island • 1 ♀, cl 3.0 mm; Marona River ; 17°33´51.860˝ S, 168°17´08.140˝ E; 5 m a.s.l.; 9 Nov. 2014; A. Accou, G. Marquet and M. Mennesson leg.; DNA voucher: CA1381; MNHN-IU-2018-2946 • 1 ♀ ovig., cl 3.4 mm; Mele River ; 17°40.578´S, 168°15.462´E; 9 Nov. 2014; 32 m a.s.l.; A. Acou, G. Marquet and M. Mennesson leg.; MNHN-IU-2018-2947 .

Description

CEPHALOTHORAX. Antennal spine ventral to inferior orbital angle. Pterygostomian margin rounded. Rostrum ( Fig. 24k ): straight, 0.6–0.7 of cl, reaching to base of third segment of antennular peduncle, armed with 17–22 teeth on dorsal margin, 6–8 of them situated on carapace behind orbital margin, ventral margin with 4–7 teeth. Eyes developed, anterior end reaching to 0.66 times length of basal segment of antennular peduncle. Long antennular peduncle, 0.57–0.75 (♀) times as long as carapace. Anterolateral angle reaching 0.22 times length of second segment, second segment distinctly longer than third segment. Stylocerite reaching just beyond beginning of second segment of antennular peduncle.

PEREIOPODS. Epipods on first four pereiopods. P1 ( Fig. 24a ): chela about 2.7–2.8 times as long as wide, movable finger 3.6–4.5 times as long as wide, 1.0–1.7 times length of palm; carpus 4.0–5.0 times as long as wide. P2 ( Fig. 24b ) more slender and longer than first pereiopod, with chela 5.5–6.6 times as long as wide: movable finger 6.4–8.1 times as long as wide, 1.2–1.3 times length of palm; carpus slender, 11.9–12.0 times as long as wide. P3 ( Fig. 24c ): slender, dactylus ( Fig. 24e ) 3.7–4.6 times as long as wide (terminal spiniform seta included), with 7–10 spiniform setae on flexor margin including terminal one; propodus 12.4–13.2 times as long as wide, 3.5–4.0 times as long as dactylus. P5 ( Fig. 24d ): dactylus ( Fig. 24f ) 4.7–5.1 as long as wide, with 10–15 spiniform setae on flexor margin; propodus 15.0–16.2 times as long as wide, 3.7–3.9 times as long as dactylus.

ABDOMEN. Third abdominal somite with moderately convex dorsal profile. Sixth abdominal somite 0.58 times as long as carapace, 1.7 times as long as fifth somite, shorter than telson.

TELSON ( Fig. 24i ). 2.4 times as long as wide, with four or five pairs of dorsal spinules and pair of dorsolateral spinules; posterior margin with median process, rounded, with 9–11 very long intermediate setae longer than lateral ones.

MALE PLEOPODS. No males.

PRE- ANAL CARINA ( Fig. 24g ). High, with a spine.

UROPODAL DIAERESIS ( Fig. 24h ). With 13–17 spinules.

EGGS. Size: 0.30–0.38 × 0.18–0.23mm.

Habitat

Caridina celebensis lives essentially in the estuarine brackish waters in the lower course of rivers.

Colour pattern

Unknown.

Distribution

This species occurs in Indonesia (Sulawesi), the Solomon Islands, Vanuatu and the Philippines (Palawan).

Remarks

According to Holthuis (1978), C. celebensis can be separated from 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 less dorsal teeth 17–22 (vs 22–26). Its P2 carpus is longer, 11.9–12.0 as long as wide (vs 8.3–10.9), and also its P2 chela is 5.5–6.6 times as long as wide (vs 3.7–5.1), but its movable finger is 1.2–1.3 times the length of the palm (vs 1.7–1.9), its P3 dactylus has more spiniform setae on the flexor margin in addition to the terminal one, 7–10 (vs 6–7),and its P5 propodus is 15.0–16.2 times as long as wide (vs 18.7–24.0) and 3.7–3.9 times as long as the dactylus (vs 4.5–5.5).

According to Cai & Shokita (2006b), the characters used by Holthuis are not always reliable. On the contrary, the size of the arthrobranch on the base of P 1 in C. serratirostris is highly variable, from very distinct to almost indiscernible, but is totally absent in C. celebensis .

Nevertheless, our study allowed us to find other morphological characters that separate these two species well, such as the number of teeth on the dorsal margin of the rostrum or the length of the P2 carpus.

Identification key

1. More than 6 dorsal rostrum teeth situated on carapace behind orbital margin. A long stylocerite, reaching at least the beginning of the second segment of antennular peduncle: C. serratirostris group ................................................................................................................................................. 2

– Fewer than 6 dorsal rostrum teeth situated on carapace behind orbital margin. A long or short stylocerite .......................................................................................................................................... 3

2. Rostrum with 22–26 dorsal teeth and P2 carpus 8.2–10.9 times as long as wide .............................. ............................................................................................................ C. serratirostris De Man, 1892

– Rostrum with 17–22 dorsal teeth and P2 carpus 11.9–12.0 times as long as wide ............................ ................................................................................................................ C. celebensis De Man, 1892

3. Number of spiniform setae on uropodal diaeresis 6–10 and a very long and upcurved rostrum with 5–9 dorsal teeth, widely spaced: C. gracilirostris group .................................................................. 4

– Number of spiniform setae on uropodal diaeresis 8–22 and a long or short rostrum with 8–28 dorsal teeth, closely set ................................................................................................................................ 5

4. No appendix interna on the endopod of the male first pleopod. P1 and P2 carpus 1.5–1.9 and 3.2–5.1 times as long as wide, respectively .................................................... C. gracilirostris De Man, 1892

– With an appendix interna on the endopod of the male first pleopod. P1 and P2 carpus 2.3–3.1 and 5.2–6.4 times as long as wide, respectively ............................................ C. neglecta Cai &Ng, 2007

5. Uropodal diaeresis with14–22 spinules and short rostrum, armed or not ........................................ 6

– Uropodal diaeresis with 8–17 spinules and rostrum variable in shape and length, always unarmed .......................................................................................................................................... 18

6. Telson with numerous and very long plumose intermediate setae ................. 7 ( C. weberi complex) – Telson with few long intermediate setae ..........................................................17 (C. typus complex)

7. Long stylocerite reaching to about halfway along second segment of peduncle .............................. 8 – Short stylocerite not reaching second segment of peduncle ............................................................. 9

8. P5 propodus 3.8–4.4 times as long as dactylus ............................................ C. buehleri Roux, 1934 – P5 propodus 4.4–6.2 times as long as dactylus ............. C. gueryi Marquet, Keith & Kalfatak, 2009

9. No dorsal teeth on the rostrum ........................................................................................................ 10 – 8–22 dorsal teeth on the rostrum ......................................................................................................11

10. P5 dactylus 4.9–6.6 times as long as wide and P3 propodus 8.6–11.3 times as long as wide ............ ........................................................................................................................... C. paratypus sp. nov.

– P5 dactylus 3.9–4.5 times as long as wide and P3 propodus 6.7–7.7 times as long as wide ............. ................................................................................................................................ C. poarae sp. nov.

11. Dorsal teeth of rostrum situated considerably anterior to orbital margin ....................................... 12 – Dorsal teeth of rostrum situated all along its length ....................................................................... 14

12. 8–7 large teeth on dorsal margin of rostrum ............................................................. C. nana sp. nov. – 8–15 small teeth on dorsal margin of rostrum ................................................................................ 13

13. P5 dactylus biunguiculate .................................................................................... C. maeana sp. nov. – P5 dactylus unguiculate ....................................... C. tupaia de Mazancourt, Marquet & Keith, 2019

14. Telson with one or two lateral pairs of setae, with 11–22 dorsal teeth ........ C. weberi De Man, 1892 – Telson always with one pair of lateral setae, with 9–13 dorsal teeth .............................................. 15

15. 0–1 post-orbital teeth on the dorsal margin of the rostrum ............................................................. 16 – 2 or more post-orbital teeth on the dorsal margin of the rostrum ........................ C. sikipozo sp. nov.

16. P3 dactylus 2.8–3.0 times as long as wide............................................................ C. piokerai sp. nov. – P3 dactylus 3.0–3.3 times as long as wide................................................... C. papuana Nobili, 1905

17. Rostrum with no dorsal teeth ......................................................... C. typus H. Milne Edwards, 1837 – Rostrum with dorsal teeth ........................................................................................ C. turipi sp. nov.

18. P1 carpus shaped as a half crescent; no apical tooth on the rostrum ................ C. barakoma sp. nov. – P1 carpus more or less long; 1–5 apical teeth on the rostrum ......................19 ( C. nilotica complex)

19. Very long rostrum, 1.1–2.1 times as long as carapace .................................................................... 20 – Moderately long rostrum, variable, 0.5–1.2 times as long as carapace .......................................... 22

20. Pre-anal carina without a spine ............................................................... C. brevidactyla Roux, 1919 – Pre-anal carina with a spine ............................................................................................................ 21

21. Rostrum with 12–18 dorsal teeth, somewhat irregularly spaced, 8–12 dorsal teeth before the first ventral teeth ...................................................................... C. appendiculata Jalihal & Shenoy, 1998 – Rostrum with 16–26 dorsal teeth, closely set, 11–16 dorsal teeth before the first ventral teeth ......... .......................................................................................................................... C. intermedia sp. nov.

22. Pre-anal carina always without a spine; rostrum with 4–9 ventral teeth ....... C. mertoni Roux, 1911 – Pre-anal carina with or without a spine; rostrum with 6–18 ventral teeth ...................................... 23

23. Pre-anal carina always with a spine, pterygostomial margin rounded .................. C. pisuku sp. nov. – Pre-anal carina with or without a spine, pterygostomial margin subrectangular ................................ .............................................................................................................................. C. choiseul sp. nov.

Figures

Fig. 2. Bayesian inference phylogenetic tree of the species studied. Numbers above branches are Bayesian posterior probabilities, numbers under branches are Maximum Likelihood bootstrap values. Results of the three species delimitation methods are indicated by the black bars on the right of the tree. Each bar represents a species recognized by the analysis.

Fig. 24. Caridina celebensis De Man, 1892. a. First pereiopod. b. Second pereiopod. c. Third pereiopod. d. Fifth pereiopod. e. Dactylus of third pereiopod. f. Dactylus of fifth pereiopod. g. Pre-anal carina. h. Uropodal diaeresis. i. Telson. j. Eggs. k. Cephalothorax. MNHN-IU-2018-2944 (a–f, j), MNHN- IU-2018-2946 (g) and MNHN-IU-2018-2943 (h–i, k).