The freshwater shrimp family Euryrhynchidae Holthuis, 1950 (Crustacea: Decapoda: Caridea) revisited, with a taxonomic revision of the genus Euryrhynchus Miers, 1878 Author Pachelle, Paulo P. G. Author Tavares, Marcos text Zootaxa 2018 2018-02-19 4380 1 journal volume 30720 10.11646/zootaxa.4380.1.1 099d3015-8af8-4ae1-b667-1ac61dde9294 1175-5326 1175650 9DC29ECD-8C44-4F42-BA0E-9B0C830A7C73 Genus Euryrhynchoides Powell, 1976 Euryrhynchoides Powell, 1976 : 885 . Gender masculine. Euryrhynchoides — Powell 1977 : 650; Holthuis 1993 : 184; Pereira 1997 : 3, tab. 5; De Grave 2007 : 193; De Grave et al. 2008 : 291; De Grave et al. 2009 : 17; De Grave & Fransen 2011 : 309; De Grave et al. 2015 : 4; De Grave et al. 2017 : 120. Recognition characters. Rostrum with 2–3 teeth on dorsal margin, ventral margin smooth, non-dentate. Distomesial region of ocular peduncles not produced anteriorly, not reaching distal margin of cornea. Distolateral margin of stylocerite with cluster of simple setae. Accessory ramus of antennule with aesthetacs distributed on distal 3 articles. Third maxilliped with 2 arthrobranchs. Third and fourth pereopod carpus with cuspidate seta on distoventral margin. Third to fifth pereopod dactylus with cuspidate setae on dorsal margin. Male second pleopod with endopod not spatulate, modified into gonopod with accessory branch; appendices masculina and interna lacking. Uropodal exopod with more than 3 cuspidate setae on diaeresis, decreasing in size towards lateral margin. Type species. Euryrhynchoides holthuisi Powell, 1976 , by monotypy. Species included. Genus monotypic. Distribution. Sierra Leone (Moyamba district) and Nigeria ( Rivers State) ( Powell 1976 ; Nwadiaro 1984 ) ( Figs. 2 , 62 , blue circles). Remarks. The genus includes the largest representatives of the family, with adult specimens up to 10.3 mm of carapace length (based on the examined specimens). Euryrhynchoides is unique within the family in having a dorsally dentate rostrum, the aesthetascs of the accessory ramus of antennule present on the distal and antepenultimate articles, and the second male pleopod with a biramous gonopod, but lacking an appendix interna ( Powell 1976: fig. 1B, F; Fig. 5 A , D, E ). Euryrhynchoides shares with Euryrhynchus the distomesial region of the ocular peduncles not anteriorly produced, the stylocerite with a cluster of setae on the distolateral margin, the presence of arthrobranch on the third maxilliped, the second male pleopod with a gonopod, and the uropodal diaeresis with more than 3 cuspidate setae ( Powell 1976: figs. 1C, D, 2H, 4B–D; see also Figs. 9 A , 11D, E, G , 13B , 17B–E ).