Thursday, August 6, 2020

[Crustacea • 2020] Solomon’s Gold Mine: Description or Redescription of 24 Species of Caridina Freshwater Shrimps (Decapoda: Atyidae) from the Solomon Islands, including 11 New Species


 amphidromous freshwater shrimps of the genus Caridina from  the Solomon Islands

Mazancourt, Boseto, Marquet & Keith, 2020
Photographs by P. Keith and C. Lord. 

Abstract
 Following recent (2014–2017) collections made in the Solomon Islands by the MNHN and the NGO ESSI, we provide a checklist of the species of amphidromous freshwater shrimps of the genus Caridina H. Milne Edwards, 1837 from this region. Using morphological as well as molecular data in an integrative taxonomic perspective, we found a total of 24 species, including 11 new for science, that are described or re-described, illustrated and discussed in relation to their habitat and distribution. Newly described species are Caridina barakoma sp. nov., C. choiseul sp. nov., C. intermedia sp. nov., C. maeana sp. nov., C. nana sp. nov., C. piokerai sp. nov., C. pisuku sp. nov., C. paratypus sp. nov., C. poarae sp. nov., C. sikipozo sp. nov. and C. turipi sp. nov. Caridina gueryi Marquet, Keith & Kalfatak, 2009 is re-validated as a species distinct from C. buehleri Roux, 1934. Lectotypes are designated for C. mertoni Roux, 1911 and C. papuana Nobili, 1905. Diagnoses for 6 informative species groups are provided: C. brevicarpalis group, C. gracilirostris group, C. nilotica group, C. typus group, C. serratirostris group and C. weberi group. A map of the species distribution in the Solomon Islands, as well as the phylogenetic relationships between the species and their relatives, are provided. 

Keywords. Amphidromous shrimp, Pacific Ocean, integrative taxonomy, morphology, 16S.

Fig. 1. Distribution of the species studied in the Solomon Islands. Symbols are colored according to the different species complexes (see Fig. 2): brown for C. brevicarpalis complex, blue for C. nilotica complex, red for C. weberi complex, grey for C. typus complex, green for C. gracilirostris complex and yellow for C. serratirostris complex.

Fig. 25. Live colourations. A. Caridina gracilirostris De Man, 1892 (MNHN-IU-2018-2804). B. Caridina neglecta Cai & Ng, 2007 (MNHN-IU-2018-2811). C. Caridina appendiculata Jalihal & Shenoy, 1998 (MNHN-IU-2018-135). D. Caridina brevidactyla Roux, 1919 (CA1503). E. Caridina choiseul sp. nov. (Choiseul Island). F. Caridina intermedia sp. nov. (MNHN-IU-2014-20847). G. Caridina mertoni Roux, 1911 (Kolombangara Island). Photographs by P. Keith (A–G).

Fig. 26. Live colourations. A. Caridina buehleri Roux, 1934 (MNHN-IU-2015-20). B. Caridina gueryi Marquet, Keith & Kalfatak, 2009 (MNHN-IU-2015-19). C. Caridina weberi De Man, 1892 (Kolombangara Island). D. Caridina serratirostris De Man, 1892 (MNHN-IU-2018-2931). E. Caridina papuana Nobili, 1905 (Choiseul Island). Habitats in the Solomon Islands. F. Caridina maeana sp. nov. (Choiseul Island). G. Lentic mode, Lodumoe river, Kolombangara Island. H. Lotic mode, Sulumuni river, Kolombangara Island. 
Photographs by P. Keith (A, D–F, H) and C. Lord (B–C, G). 


Valentin de Mazancourt, David Boseto, Gerard Marquet and Philippe Keith. 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: 1–86. DOI: 10.5852/ejt.2020.696