taxonID	type	description	language	source
03FCE86DFFC7DF2810515CD696B6FC89.taxon	diagnosis	Diagnosis Slender morphology, with a mostly long rostrum (longer than the antennular peduncle) but variable, the antennal spine ventral to the inferior orbital angle, a long antennular peduncle (subequal to carapace length), segments of walking legs slender, a typical dorsal hump over the third abdominal somite, a long sixth abdominal somite (always more than half of carapace length), a small pre-anal carina sometimes bearing an acute spine, a moderate number of spinules on the uropodal diaeresis (<15), fewer, medium to short and terminal setae on the telson and a subtriangular endopod of the first male pleopod with or without an appendix on the subdistal outer margin or even placed at the distal end. An oblique red band on the cephalothorax is very characteristic.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC7DF2B10565EBE9174FCE7.taxon	materials_examined	Type locality Near Port-Louis, Mauritius. Material examined No material examined.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC7DF2B10565EBE9174FCE7.taxon	distribution	Distribution Endemic to Mauritius. Habitat Freshwater.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC7DF2B10565EBE9174FCE7.taxon	discussion	Remarks This small species seems rare and a DNA barcode sequence would be needed to complete our sampling.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC4DF2A10455E729174FE20.taxon	description	Figs 2 D, 5 B	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC4DF2A10455E729174FE20.taxon	materials_examined	Type locality Umgeni River, Durban, Natal, South Africa. Material examined See de Mazancourt et al. 2019 a.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC4DF2A10455E729174FE20.taxon	distribution	Distribution Comoros (Anjouan, Mohéli), Mayotte, Seychelles (La Digue, Mahé, Praslin and Silhouette), Mauritius, La Réunion (?), Madagascar, South Africa, Tanzania and Kenya. Habitat Freshwater in the lower course of rivers.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC4DF2A10455E729174FE20.taxon	discussion	Remarks This species is easily identified by its rostrum rather constantly long, reaching well beyond scaphocerite.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC5DF25103E5CCE97E6FC6C.taxon	description	Figs 2 B, 5 C	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC5DF25103E5CCE97E6FC6C.taxon	materials_examined	Type locality Pamplemousses Botanical Garden, Mauritius. Material examined Caridina spathulirostris Richters, 1880 MAURITIUS • 1 ♀ ovig. (cl 3.9 mm), 1 ♀ (cl 5.3 mm); quartier militaire, rivière importante; 20 ° 17.260 ′ S, 57 ° 35.948 ′ E; 390 m a. s. l.; 10 Dec. 2005; C. R. Turner leg.; MNHN-Na 772; MNHN • 1 ♀ (cl 5.8 mm); same data as for preceding; DNA voucher: CA 2165; MNHN- 2025 - 125; MNHN. Caridina richtersii Thallwitz, 1891 MAURITIUS • 1 ♀ ovig. (cl 5.8 mm); quartier militaire, rivière importante; 20 ° 17.260 ′ S, 57 ° 35.948 ′ E; 390 m a. s. l.; 10 Dec. 2005; C. R. Turner leg.; DNA voucher: CA 2166; MNHN- 2025 - 126; MNHN • 1 ♂ (cl 6.5 mm); same data as for preceding; DNA voucher: CA 2167; MNHN- 2025 - 127; MNHN.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC5DF25103E5CCE97E6FC6C.taxon	distribution	Distribution Endemic to Mauritius. Habitat Freshwater in rivers and ponds.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC5DF25103E5CCE97E6FC6C.taxon	discussion	Remarks Our genetic study shows that Caridina richtersi Thallwitz, 1891 and C. spathulirostris Richters, 1880 are conspecific and we consider the former to be a junior synonym of C. spathulirostris. The specimens of this species are polymorphic in the shape of the rostrum and the chelipeds, which led to the description of numerous forms like C. spathulirostris f. rectirostris, C. spathulirostris f. curvirostris, C. richtersi f. typica, C. richertsi f. apiocheles. This kind of variability was also described in another endemic species of Caridina from the SWIO, C. similis (see Marquet & Keith, 2008).	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCADF24106C5EFB904EFD96.taxon	description	Figs 2 C, 5 E	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCADF24106C5EFB904EFD96.taxon	materials_examined	Type locality Mahé, Seychelles. Material examined SEYCHELLES ‒ Mahé • 8 ♀♀ ovig. (cl 4.7 ‒ 6.3 mm), 1 ♀ (cl 5.9 mm), 1 ♂ (cl 4.1 mm); mare aux cochons; 4 ° 39.029 ′ S, 55 ° 24.152 ′ E; 17 Feb. 2020; P. Keith and M. Mennesson leg.; MNHN- 2025 - 128; MNHN • 3 juv. (cl 2.4 ‒ 2.9 mm); Baume Ellie; 14 Feb. 2020; P. Keith and M. Mennesson leg.; MNHN- 2025 - 129; MNHN. ‒ Silhouette • 1 ♀ ovig. (cl 4.4 mm); Anse Mandon; 4 ° 28 ′ 1 ″ S, 55 ° 13 ′ 30 ″ E; 28 Nov. 2012; P. Keith leg.; DNA voucher: CA 1854; MNHN- 2025 - 130; MNHN • 1 ♂ (cl 3.9 mm); same data as for preceding; DNA voucher: CA 1855; MNHN- 2025 - 131; MNHN • 1 ♀ ovig. (cl 5.5 mm); same data as for preceding; DNA voucher: CA 1856; MNHN- 2025 - 132; MNHN • 1 ♀ ovig. (cl 5.6 mm); same data as for preceding; DNA voucher: CA 1857; MNHN- 2025 - 133; MNHN. See also “ other material ” in Marquet & Keith (2008).	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCADF24106C5EFB904EFD96.taxon	distribution	Distribution Endemic to the Seychelles (La Digue, Mahé, Praslin, Silhouette). Habitat Freshwater in permanent rivers.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCADF24106C5EFB904EFD96.taxon	discussion	Remarks As for the previous species, C. similis shows a very variable form of the rostrum indicating numerous forms like Caridina brevirostris f. similis, Caridina brevirostris f. typica, Caridina brevirostris f. Gardineri now all junior synonyms of C. similis (see Marquet & Keith 2008).	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCBDF2410635FAF9046FC1D.taxon	diagnosis	Diagnosis Robust morphology with a straight rostrum, armed or not on the dorsal margin, without apical teeth, antennal spine fused with inferior orbital angle, antennular peduncle equal or more than half of carapace in length, pterygostomian margin blunt to rather narrowly rounded, stout walking legs, carpus of first pereiopod excavated, short sixth abdominal somite (less than half of carapace length), high pre-anal carina with no spine or a small one, a great number of spinules on the uropodal diaeresis (> 15), plumose terminal setae on the telson subequal to lateral ones or slightly longer, and a long subrectangular endopod of the first male pleopod with a short appendix on the subdistal outer margin.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCBDF261022590B95BEFBD9.taxon	description	Figs 2 G, 5 F	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCBDF261022590B95BEFBD9.taxon	materials_examined	Type locality Unknown, probably Mauritius according to Bouvier (1925). Material examined AUSTRALIA • 2 specs from GenBank: DQ 478562 and DQ 478563 (Page et al. 2007). MADAGASCAR • 1 ♀ (cl 4.5 mm); Antsatoko River; 13 ° 36.660 ′ S, 50 ° 00.341 ′ E; 29 m a. s. l.; 6 Jul. 2008; DIAMSOI leg.; DNA voucher: CA 1038; MNHN-IU- 2018 - 2829; MNHN • 1 ♀ ovig. (cl 6.9 mm); same data as for preceding; DNA voucher: CA 1040; MNHN-IU- 2018 - 2830; MNHN • 1 ♀ ovig. (cl 7.1 mm); same data as for preceding; DNA voucher: CA 1039; MNHN-IU- 2018 - 2831; MNHN. MAYOTTE • 1 ♀ (cl 6.1 mm); M’Tsangachei River; 12 ° 53.066 ′ S, 45 ° 07.899 ′ E; 30 Mar. 2024; P. Valade leg.; DNA voucher: CA 3027; MNHN-IU- 2025 - 134; MNHN. MAURITIUS • 3 specs from GenBank: KY 069380, KY 069381 and KY 069382 (Bernardes et al. 2017). SEYCHELLES • 1 ♀ (cl 9.2 mm); Praslin Island, Nouvelle Découverte River; 4 ° 19.200 ′ S, 55 ° 42.333 ′ E; 16 m a. s. l.; 8 Oct. 2003; P. Bosc, H. Grondin, P. Keith and P. Valade leg.; MNHN-IU- 2014 - 577; MNHN. SOUTH AFRICA • 1 ♀ ovig. (cl 10.1 mm); Umtata River; 31 ° 55.511 ′ S, 29 ° 08.199 ′ E; 2 m a. s. l.; 13 Feb. 2018; L. Maliwa, M. Mlambo, G. Marquet and P. Tiberghien leg.; DNA voucher: CA 2089; MNHN- 2018 - 2843; MNHN • 1 ♂ (cl 5.7 mm); Mpenjati River; 30 ° 56.645 ′ S, 30 ° 13.660 ′ E; 93 m a. s. l.; 15 Feb. 2018; P. Kubheka, N. McClurg, T. McClurg, L. Maliwa, M. Mlambo, G. Marquet and P. Tiberghien leg.; DNA voucher: CA 2090; MNHN-IU- 2018 - 2844; MNHN. LA RÉUNION • 1 juv. (cl 2.4 mm); Rivière du Mât; 20 ° 58.801 ′ S, 55 ° 41.989 ′ E; 19 May 2023; P. Valade leg.; DNA voucher: CA 3054; MNHN-IU- 2025 - 135; MNHN • 1 ♂ (cl 4.6 mm); same data as for preceding; DNA voucher: CA 3058; MNHN-IU- 2025 - 136; MNHN • 1 juv. (cl 2.4 mm); same data as for preceding; DNA voucher: CA 3059; MNHN-IU- 2025 - 137; MNHN • 1 juv. (cl 1.9 mm); Rivière des Marsouins; 21 ° 01. 970 ′ S, 55 ° 42.943 ′ E; 6 Aug. 2023; P. Valade leg.; DNA voucher: CA 3060; MNHNIU- 2025 - 138; MNHN • 1 ♂ (cl 4.5 mm); same data as for preceding; DNA voucher: CA 3063; MNHNIU- 2025 - 139; MNHN • 1 spec. from GenBank: KY 069434 (Bernardes et al. 2017).	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCBDF261022590B95BEFBD9.taxon	distribution	Distribution Widespread from South Africa to Fiji and Australia to Japan and India.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCBDF261022590B95BEFBD9.taxon	biology_ecology	Habitat Freshwater in rivers.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFCBDF261022590B95BEFBD9.taxon	discussion	Remarks Caridina typus revealed to be a species complex, all characterized by the lack of teeth on the dorsal margin of the rostrum. Three clades were recognized by Bernardes et al. (2017), named SUL, TAL and ARC. The latter one corresponds to the true C. typus, while SUL is C. jeani and TAL is C. zhujiangensis (publication in prep.).	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF261031596F9003FA3E.taxon	diagnosis	Diagnosis Moderately robust morphology with a moderately short and straight rostrum (reaching end of antennular peduncle), armed with many dorsal teeth, at least 6 of them on the carapace, without apical teeth, the antennal spine ventral to the inferior orbital angle, a long antennular peduncle (about half the carapace length) with an usually long stylocerite (reaching end of first segment of antennular peduncle), pterygostomian margin rounded, segments of walking legs very slender, sixth abdominal somite about half of carapace length, a small pre-anal carina sometimes bearing an acute spine, a great number of spinules on the uropodal diaeresis (> 15), numerous, long and plumose terminal setae on the telson and a rounded endopod of the first male pleopod, without appendix interna.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	description	urn: lsid: zoobank. org: act: F 229 A 5 EF- 5 D 4 B- 412 D-B 6 F 8 - 285 C 1 B 0 B 1 C 27 Figs 2 F, 3 ‒ 4, 5 D, G – H	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	diagnosis	Diagnosis Typical morphology of the C. serratirostris species group: rostrum armed with many dorsal teeth, at least 6 of them on the carapace, a usually long stylocerite and a rounded endopod of the first male pleopod, without appendix interna. Well-developed arthrobranch at the base of P 1. Telson with a pair of plain long lateral spines and 1 pair of shorter, plain lateral spines. P 3 propodus 11.2 ‒ 12.8 as long as wide.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	etymology	Etymology The new species is dedicated to our friend Elvina Henriette, Research Scientist and Director of the NGO “ Gaea Conservation Network Seychelles ”, in recognition of her work and passion for the freshwater fauna of Seychelles islands.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	materials_examined	Type material Holotype MAURITIUS • ♂ (cl 2.9 mm); Rivière des Anguilles; 20 ° 28.802 ′ S, 57 ° 33.378 ′ E; 13 Nov. 2002; P. Keith, G. Marquet and ARDA leg.; DNA voucher: CA 2304; MNHN-IU- 2015 - 1914; MNHN. Paratypes MAURITIUS • 1 ♀ (cl 4.1 mm); same data as for for holotype; DNA voucher: CA 2305; MNHN- 2025 - 140; MNHN. MADAGASCAR • 1 ♀ ovig. (cl 4.9 mm); Fanambana River (Station 37); 14 ° 33.193 ′ S, 50 ° 10.393 ′ E; 11 m a. s. l.; 7 Jul. 2008; DIAMSOI leg.; DNA voucher: CA 1178; MNHN- 2025 - 141; MNHN • 1 ♂ (cl 3.2 mm); same collection data as for preceding; DNA voucher: CA 1431; MNHN- 2025 - 142; MNHN. MAURITIUS • 1 ♀ ovig. (cl 4.8 mm); Rivière de la Chaux; 20 ° 24.350 ′ S, 57 ° 42.269 ′ E; 12 Nov. 2002; ARDA leg.; DNA voucher: CA 2042; MNHN-IU- 2015 - 1933; MNHN • 1 ♂ (cl 3.0 mm); Beau Vallon; 1913; P. Carié leg.; MNHN-IU- 2015 - 1909; MNHN. LA RÉUNION • 1 ♀ ovig. (cl 4.4 mm); Rivière des Embouchures; 21 ° 2.093 ′ S, 55 ° 42.899 ′ E; 13 Oct. 2015; P. Valade leg.; DNA voucher: CA 2417; MNHN- 2025 - 143; MNHN • 1 ♀ ovig. (cl 3.8 mm); same data as for preceding; DNA voucher: CA 2418; MNHN- 2025 - 144; MNHN • 1 ♀ ovig. (cl 3.6 mm); Rivière des Marsouins; 2 May 2022; Ocea Consult leg.; DNA voucher: CA 2949; MNHN- 2025 - 145; MNHN • 1 ♀ ovig. (cl 3.6 mm); Rivière des Marsouins; 21 ° 1.970 ′ S, 55 ° 42.949 ′ E; 8 Apr. 2024; P. Valade leg.; DNA voucher: CA 3038; MNHN- 2025 - 146; MNHN • 1 juv. (cl 2.4 mm); Rivière des Marsouins; 21 ° 1.970 ′ S, 55 ° 42.949 ′ E; 6 Aug. 2023; P. Valade leg.; DNA voucher: CA 3061; MNHN- 2025 - 147; MNHN • 1 juv. (cl 2.3 mm); Rivière des Roches; 21 ° 0.398 ′ S, 55 ° 41.661 ′ E; 13 Nov. 2023; P. Valade leg.; DNA voucher: CA 3065; MNHN- 2025 - 148; MNHN. SEYCHELLES ‒ Mahé • 2 ♀♀ ovig. (cl 4.1 ‒ 4.7 mm), 1 ♀ (cl 4.0 mm); Bel Ombre; 4 ° 36.966 ′ S, 55 ° 25.063 ′ E; 2 Feb. 2020; P. Keith and M. Mennesson leg.; MNHN- 2025 - 149; MNHN • 1 ♀ ovig. (cl 2.7 mm); Grand Anse; 4 ° 40.502 ′ S, 55 ° 26.728 ′ E; 20 Feb. 2020; P. Keith and M. Mennesson leg.; MNHN- 2025 - 150; MNHN • 1 ♀ ovig. (cl 2.7 mm); same data as for preceding; DNA voucher: CA 3000; MNHN- 2025 - 151; MNHN. ‒ Praslin • 1 ♀ ovig. (cl 4.1 mm); 10 Oct. 2003; no locality data; ARDA leg.; DNA voucher: CA 2026; MNHN-IU- 2015 - 1932; MNHN • 1 ♀ ovig. (cl 3.4 mm); Nouvelle Découverte; 4 ° 20.179 ′ S, 55 ° 43.349 ′ E; 19 Feb. 2024; P. Keith and M. Mennesson leg.; MNHN- 2025 - 152; MNHN • 2 ♀♀ ovig. (cl 3.2 ‒ 3.6 mm); Nouvelle Découverte; 4 ° 20.179 ′ S, 55 ° 43.349 ′ E; 21 Feb. 2020; P. Keith and M. Mennesson leg.; MNHN- 2025 - 153; MNHN • 1 ♀ ovig. (cl 3.6 mm); same data as for preceding; DNA voucher: CA 2998; MNHN- 2025 - 154; MNHN • 1 ♀ ovig. (cl 3.4 mm); same data as for preceding; DNA voucher: CA 2999; MNHN- 2025 - 155; MNHN. ‒ Silhouette • 1 ♀ (cl 3.4 mm); Anse Mandon; 4 ° 28.014 ′ S, 53 ° 13.500 ′ E; 28 Nov. 2012; P. Keith leg.; DNA voucher: CA 1491; MNHN- 2025 - 156; MNHN • 1 ♀ ovig. (cl. 4.5 mm); same data as for preceding; DNA voucher: CA 1492; MNHN- 2025 - 157; MNHN • 4 ♀♀ ovig. (cl 3.3 ‒ 3.7 mm), 1 ♀ (cl 3.3 mm); St Gore River; 4 ° 30.115 ′ S, 55 ° 13.521 ′ E; 18 Feb. 2020; P. Keith and M. Mennesson leg.; MNHN- 2025 - 158; MNHN.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	description	Description CEPHALOTHORAX. Antennal spine ventral to inferior orbital angle. Pterygostomian margin rounded. Rostrum (Fig. 3 M – O): straight, short, 0.6 – 0.7 of cl, reaching beyond end of antennular peduncle, armed with 19 – 31 teeth on dorsal margin, 6 – 10 of them situated on carapace behind orbital margin, ventral margin with 5 – 7 teeth. Eyes developed, anterior end reaching to 0.59 × length of basal segment of antennular peduncle. Long antennular peduncle, 0.67 (♀) – 0.78 (♂) × as long as carapace; second segment distinctly longer than third segment. Stylocerite reaching to middle of second segment of antennular peduncle. PEREIOPODS. Epipods on first four pereiopods. P 1 (Fig. 3 A): chela about 2.4 – 3.3 × as long as wide, movable finger 3.7 ‒ 5.8 as long as wide, 1.4 – 1.9 × length of palm; carpus 3.6 – 4.6 × as long as wide, well developed arthrobranch (Fig. 4). P 2 (Fig. 3 B) more slender and longer than first pereiopod, with chela 3.7 – 5.2 × as long as wide: movable finger 5.2 ‒ 11.0 × as long as wide, 1.4 – 2.4 × as long as palm; carpus slender, 7.7 ‒ 9.6 × as long as wide. P 3 (Fig. 3 C): slender, dactylus (Fig. 3 E) 3.2 – 4.0 × as long as wide (terminal spiniform seta included), with 5 – 8 spiniform setae on flexor margin including terminal one; propodus 11.2 ‒ 12.8 × as long as wide, 3.2 ‒ 4.4 × as long as dactylus. P 5 (Fig. 3 D): dactylus (Fig. 3 F) 3.9 ‒ 4.4 as long as wide, with 7 ‒ 13 spiniform setae on flexor margin; propodus 15.8 ‒ 23.9 × as long as wide, 4.4 – 50 × as long as dactylus. ABDOMEN. Third abdominal somite with moderately convex dorsal profile. Sixth abdominal somite 0.49 × as long as carapace, 1.3 × as long as fifth somite, shorter than telson. TELSON (Fig. 3 H). 3.0 × as long as wide, with 6 pairs dorsal spines including subterminal spines, 1 pair of plain long lateral spines, 1 pair of shorter plain lateral spines and 6 ‒ 11 long, stalked, plumose processes present at rounded posterior margin. MALE PLEOPODS. Pl 1 (Fig. 3 J): endopod rounded, 2.0 × as long as wide, reaching 0.35 × as long as endopod, no appendix. Pl 2 (Fig. 3 K): appendix masculina reaching 0.74 × as long as endopod; appendix interna reaching 0.82 × as long as appendix masculina. PRE-ANAL CARINA (Fig. 3 I). High, with a spine. UROPODAL DIAERESIS (Fig. 3 G). With 13 – 15 spinules. EGGS. Ovigerous females with small eggs (Fig. 3 L), size: 0.37 – 0.46 × 0.24 – 0.27 mm.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	distribution	Distribution South Africa, Mozambique, Madagascar, Seychelles, Comoros, La Réunion, Mauritius.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	biology_ecology	Habitat Fresh or brackish water in the lower course and estuary of rivers.	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
03FCE86DFFC9DF3C107C5B2C9174FC02.taxon	discussion	Remarks This new species belongs to the Caridina serratirostris species group based on the presence of a rostrum armed with many dorsal teeth, at least 6 of them on the carapace, with a usually long stylocerite and with a rounded endopod of the first male pleopod, without appendix interna. But it is easy to distinguish this new species from type specimens of congeners by its telson with a pair of plain long lateral spines and 1 pair of shorter, plain lateral spines (vs only a pair of plain lateral spines) and by its P 3 propodus shorter 11.2 ‒ 12.8 × as long as wide (vs 14.2 ‒ 17.1). Among this group, our new species is closer to C. serratirostris than C. celebensis due to the presence of a well-developed arthrobranch at the base of the P 1 (vs reduced or absent, see Cai & Shokita 2006 b) Richard & Clark (2010) reported this species under the name C. serratirostris from Mozambique and South Africa noting the presence of shorter inner lateral spines on the telson which the syntypes of C. serratirostris do not possess. Recent sampling trips to the localities where the species was collected in South Africa – the iLovu or the Umbilo rivers near Durban ‒ by two of the authors (VM and GM) failed to retrieve this species, suggesting either that this area is the southern limit of its range and its presence may be occasional, or that the species does not occur there anymore due to the heavy urbanization around these rivers (pers. obs.).	en	Mazancourt, Valentin De, Mennesson, Marion, Marquet, Gérard, Keith, Philippe (2025): Revision of the species of Caridina (Decapoda: Atyidae) from the Western Indian Ocean islands with description of a new species. European Journal of Taxonomy 1007: 57-86, DOI: 10.5852/ejt.2025.1007.2995, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2995/13471
