Caridina choiseul, Mazancourt & Boseto & Marquet & Keith, 2020

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: 19-23

publication ID

https://doi.org/10.5852/ejt.2020.696

publication LSID

lsid:zoobank.org:pub:265EDD08-7AA8-4835-B7F6-353E7992633E

DOI

http://doi.org/10.5281/zenodo.4336346

persistent identifier

http://treatment.plazi.org/id/4C3B5DD9-C268-4876-AE84-5FF7CDD01DAE

taxon LSID

lsid:zoobank.org:act:4C3B5DD9-C268-4876-AE84-5FF7CDD01DAE

treatment provided by

Valdenar

scientific name

Caridina choiseul
status

sp. nov.

Caridina choiseul   sp. nov.

urn:lsid:zoobank.org:act:4C3B5DD9-C268-4876-AE84-5FF7CDD01DAE

Figs 2J View Fig , 6 View Fig , 25E View Fig

Caridina   sp. 2 Solomon – de Mazancourt et al. 2019a: 166, 169–170.

Etymology

Named after the island of Choiseul, where this new species occurs. The name is used as a noun in apposition.

Material examined

Holotype

SOLOMON ISLANDS • ♂, cl 3.9 mm; Choiseul Island, Creek 2; 06°59.027´S, 156°47.913´E; 93 m a.s.l.; 14 Oct. 2014; P. Gerbeaux, P. Keith and G. Marquet leg.; MNHN-IU-2014-20821. GoogleMaps  

Paratypes

SOLOMON ISLANDS – Choiseul Island • 1 ♀, cl 4.5 mm; same collection data as for holotype; MNHN-IU-2014-20822 GoogleMaps   1 ♂, cl 3.8 mm; Lopakare River ; 07°01.613´S, 156°46.567´E; 20 Oct. 2014; P. Gerbeaux, P. Keith and G. Marquet leg.; MNHN-IU-2014-20823 GoogleMaps   1 ♂, cl 4.0 mm; same collection data as for preceding; MNHN-IU-2014-20824 GoogleMaps   1 ♀ ovig., cl 4.5 mm; same collection data as for preceding; MNHN-IU-2014-20825 GoogleMaps   1 ♀ ovig., cl 4.7 mm; same collection data as for preceding; MNHN-IU-2014-20826 GoogleMaps   1 ♀, cl 4.6 mm; same collection data as for preceding; DNA voucher: CA1277; MNHN-IU-2014-20827 GoogleMaps   1 ♀, cl 4.8 mm; same collection data as for preceding; MNHN- IU-2014-20828 GoogleMaps   1 ♂, cl 4.0 mm; Pisuku River , sector 1; 06°58.951´S, 156°46.582´E; 15 m a.s.l.; 10 Oct. 2014; P. Gerbeaux, P. Keith and G. Marquet leg.; MNHN-IU-2014-20829 GoogleMaps   1 ♂, cl 4.1 mm; same collection data as for preceding; DNA voucher: CA1285; MNHN-IU-2014-20830 GoogleMaps   1 ♀, cl 4.7 mm; same collection data as for preceding; MNHN-IU-2014-20831 GoogleMaps   1 ♀ ovig., cl 5.1 mm; same collection data as for preceding; MNHN-IU-2014-20832 GoogleMaps   1 ♀ ovig., cl 5.5 mm; same collection data as for preceding; MNHN-IU-2014-20833 GoogleMaps   1 ♂, cl 4.2 mm; Pisuku River , sector 2; 06°58.900´S, 156°46.685´E; 66 m a.s.l.; 10 Oct. 2014; P. Gerbeaux, P. Keith and G. Marquet leg.; MNHN-IU-2014-20834 GoogleMaps   1 ♀, cl 5.4 mm; same collection data as for preceding; MNHN-IU-2014-20835 GoogleMaps   1 ♂, 4.2 mm; Pisuku River , upstream; 06°58.965´S, 156°46.718´E; 12 Oct. 2014; P. Gerbeaux, P. Keith and G. Marquet leg.; MNHN- IU-2014-20836 GoogleMaps   1 ♀, cl 4.5 mm; same collection data as for preceding; MNHN-IU-2014-20837 GoogleMaps   1 ♀, cl 4.1 mm; same collection data as for preceding; MNHN-IU-2014-20838 GoogleMaps   1 ♀, cl 5.1 mm; same collection data as for preceding; MNHN-IU-2014-20839 GoogleMaps   .

Comparative material

Caridina variabilirostris (de Mazancourt, Marquet & Keith, 2018)  

See de Mazancourt et al. (2018a)

Caridina brachydactyla (De Man, 1908)  

INDONESIA • lectotype (designated by Richard & Clark 2010), ♀ ovig., cl 4.8 mm; Flores Island, river near Reo ; Nov. 1888; M. Weber leg.; RMNH Crust D. 977   2 paralectotypes, ♀♀ ovig., cl 5.3–5.4 mm; Flores Island, river in Mbawa ; Jan. 1889; M. Weber leg.; RMNH 2552 View Materials   1 ♀, cl 5.8 mm; Bali Island ; NMB 1054 View Materials a   2 ♂♂, cl 2.7–3.7 mm, 1 ♀ ovig., cl 4.3 mm, 1 ♀, cl 4.8 mm; Sulawesi, Palopo, Macaui (locality code: 63.10); W. Klotz leg.; ZMB   1 ♀ ovig., cl 4.0 mm; Sulawesi, Palopo, Tojo (locality code: 64.10); W. Klotz leg.; ZMB   .

Caridina elongapoda ( Liang & Yan, 1977)  

CHINA • 3 ♂♂, cl 2.8–3.5 mm, 1 ♀, cl 4.2 mm; Hong Kong, Pak Tam Chung and Kai Sai Chau (locality codes 14.11 and 22.09); W. Klotz leg.; ZMB.  

MALAYSIA • 1 ♂, cl 4.2 mm, 1 ♀, cl 4.3 mm, 1 ♀ ovig., cl 4.3 mm; Pulau Tioman , Sungai Asah; 24 Jun. 1997; Ng et al. leg.; ZRC 1998.0865 View Materials   .

Caridina peninsularis ( Kemp, 1918)  

MALAYSIA • lectotype (designated by Cai et al. 2007), ♂, cl 3.2 mm; Penang Island, Botanical Garden ; Feb. 1916; N.Anandale leg.; MNHN-IU-2015-1749   1 paralectotype, ♀ ovig., cl 5.4 mm; same collection data as for lectotype; MNHN-IU-2015-1750   1 paralectotype, ♀, cl 3.4 mm, 1 paralectotype, ♀ ovig., cl 5.2 mm, 1 paralectotype, ♂, cl 3.9 mm; same collection data as for lectotype; NHM 1919.11.1.12-21 (1761124)   .

SINGAPORE • 1 ♀ ovig., cl 5.1 mm, 1 ♂, cl 4.2 mm; Tanglin [incorrectly spelt Tangtum in NHM register and on label, see Richard & Clark 2014]; 1958; Bedford and Lanchester leg.; NHM 1958.8.7.14–17 (1749569)   .

Caridina variabilis ( de Mazancourt, Rogers & Keith, 2018)  

See de Mazancourt et al. (2018b).

Caridina sundanella ( Holthuis, 1978)  

INDONESIA • 1 syntype ♂, cl 3.6 mm, 1 syntype, ♀, cl 5.2 mm; Sumba Island , West Sumba , 4 km N of Waimangura, Waikamburu Brook, Station 450; 250 m a.s.l.; 19 Aug. 1949; E. Sutter and A. B̹hler leg.; NMB 989 View Materials a   .

Description

CEPHALOTHORAX. Carapace ( Fig. 6m View Fig ) smooth, glabrous, with sharp antennal spine placed at lower orbital angle. Pterygostomial margin subrectangular. Variable length rostrum, 0.5–1.2 of cl, 16–28 dorsal teeth closely set, leaving 0.0–0.35 unarmed distally, 1–4 post-orbital teeth present. 7–12 teeth present on ventral margin extending from proximal end either to tip or with short distal part unarmed. Number of dorsal teeth on rostrum before first ventral tooth 13–19. Eyes well developed, anterior end reaching to 0.72 times length of basal segment of antennular peduncle. Antennular peduncle 0.75 (♀) – 0.88 (♂) times as long as carapace. Anterolateral angle reaching 0.30 length of second segment, second segment distinctly longer than third segment. Stylocerite reaching to 0.83 length of basal segment of antennular peduncle.

PEREIOPODS. Slender P1 ( Fig. 6a View Fig ): chela about 1.8–2.3 times as long as wide, dactylus 3.3–4.8 times as long as wide, 1.3–1.8 length of palm; carpus 1.9–2.4 times as long as wide with shallow excavation on anterior margin. P2 ( Fig. 6b View Fig ) more slender and longer than first pereiopod: chela 2.0–27 times as long as wide, dactylus 3.8–6.3 times as long as wide, 1.3–1.8 times length of palm; carpus 4.6–7.7 times as long as wide. P3 ( Fig. 6c View Fig ): dactylus ( Fig. 6e View Fig ) 2.7–3.8 times as long as wide (terminal spiniform setae included) with 5–6 spiniform setae on flexor margin in addition to terminal one; propodus 13.0–19.6 times as long as wide, 5.0–6.8 times as long as dactylus. P5 ( Fig. 6d View Fig ): dactylus ( Fig. 6f View Fig ) 3.3–4.9 times as long as wide, with 28–41 spiniform setae on flexor margin; propodus 13.6–25.5 times as long as wide, 4.8–6.5 times as long as dactylus.

ABDOMEN. A typical dorsal hump over third abdominal somite. Sixth abdominal somite 0.7 as long as carapace, 1.9 times as long as fifth somite, slightly shorter than telson.

TELSON ( Fig. 6i View Fig ). 2.9–3.2 times as long as wide, with four pairs of dorsal spinules and one pair of dorsolateral spinules; posterior margin with a median process, distal setae short, lateral pair slightly longer than intermediate setae (4–7).

MALE PLEOPODS. Pl1 ( Fig. 6j View Fig ): endopod subtriangular, 2.1 times as long as wide, 0.15 times as long as exopod, with an appendix interna placed at distal end. Pl2 ( Fig. 6k View Fig ): appendix masculina reaching 0.56 times length of endopod; appendix interna reaching 0.70 of appendix masculina.

PRE- ANAL CARINA ( Fig. 6g View Fig ). With a spine or not.

UROPODAL DIAERESIS ( Fig. 6h View Fig ). With 9–14 spinules.

EGGS ( Fig. 6l View Fig ). Size: 0.40–0.45 × 0.24–0.28 mm.

Habitat

This species prefers fresh and well-oxygenated waters. It is found from the lower to the higher course. It is more abundant in the areas situated above waterfalls, where predators are less numerous.

Colour pattern ( Fig. 25E View Fig )

The colour of the body is hyaline with many red dots.

Distribution

As far as we know, this species is known only from Choiseul Island.

Remarks

In this new species, rostrum length is variable (cl 0.5–1.2), being longer in the lower course and shorter in the upper course, as recently found by de Mazancourt et al. (2017b) who highlighted the “Pinocchioshrimp effect” on C. variabilirostris de Mazancourt, Marquet & Keith, 2018   from Pohnpei. When the rostrum is short, the general appearance resembles that of C. mertoni Roux, 1911   , whereas when the rostrum is long, the general appearance is similar to that of C. brachydactyla De Man, 1908   . Similarly, C. variabilis de Mazancourt, Rogers & Keith, 2018   from Guam and Palau shows a longer or a shorter rostrum depending on the altitude.

Caridina choiseul   sp. nov. looks like C. variabilis   and C. variabilirostris   from Micronesia by the number of teeth and their placement on the rostrum, the proportions between the joints of pereiopods and egg size. However, it can be differentiated by the pre-anal carina that sometimes has a spine (vs always unarmed in C. variabilis   and C. variabilirostris   ) and the P5 dactylus that has more spiniform setae on the flexor margin: 28–41 (vs 13–30 and 18–29, respectively). Caridina choiseul   sp. nov. is most similar to C. brachydactyla De Man, 1908   and C. peninsularis Kemp, 1918   , but its P2 chela is stouter (2.0–2.7 times as long as wide vs 2.7–3.2 and 2.8–3.0, respectively) and the pre-anal carina which has a spine or not (vs always armed). Caridina choiseul   sp. nov. looks like Caridina elongapoda Liang & Yan, 1977   , but the pre-anal carina has a spine or not (vs always unarmed) and its P3 dactylus with 5–6 spiniform setae on the flexor margin in addition to the terminal one (vs 6–7). Caridina choiseul   sp. nov. looks like C. mertoni Roux, 1911   and C. sundanella Holthuis, 1978   , but the pre-anal carina has a spine or not (vs always unarmed) and its rostrum has 7–12 ventral teeth (vs 4–9 and 7–9, respectively).

RMNH

National Museum of Natural History, Naturalis

Kingdom

Animalia

Phylum

Arthropoda

Class

Malacostraca

Order

Decapoda

Family

Atyidae

Genus

Caridina

Loc

Caridina choiseul

Mazancourt, Valentin de, Boseto, David, Marquet, Gerard & Keith, Philippe 2020
2020
Loc

Caridina

de Mazancourt V. & Klotz W. & Marquet G. & Mos B. & Rogers D. C. & Keith P. 2019: 166
2019