Euryrhynchus amazoniensis Tiefenbacher, 1978

Santos, Maria Aparecida Laurindo dos, Castro, Patrícia Madedo de & Magalhães, Célio, 2018, Freshwater shrimps (Crustacea, Decapoda, Caridea, Dendrobranchiata) from Roraima, Brazil: species composition, distribution, and new records, Check List (Washington, D. C.: 1974) 14 (1), pp. 21-35 : 23-24

Euryrhynchus amazoniensis Tiefenbacher, 1978 ( Figs 1F–J, 7)

Identification characters ( Fig. 1F–J). Rostrum triangular, depressed, unarmed, usually not reaching distal margin of cornea. Carapace smooth, antennal tooth present; abdomen smooth, pleura of second somite enlarged and overlapping pleuron of first and third somites. Telson with posterior margin convex, its posterolateral angles with 2 pair of spines, inner pair distinctly larger than outer one. P2 (second pair of chelipds) similar in shape, not in size; merus spineless, carpus with small, sharp spine on inner distal margin. Male Plp2 with endopod shorter than exopod, with short row of setae on inner margin starting near to appendix interna, apex flattened, provided with a few setae subdistally on outer margin.

Material examined. 1 male ( INPA 2382), Bonfim, BR 401 road, igarapé Arraia, 03°21ʹ05ʺ N, 059°54ʹ12ʺ W, date unknown, colls. V. Py-Daniel et al.; 1 male ( INPA 2405), Caracaraí, vila Petrolina do Norte, Viruá National Park, [01°42ʹ25ʺ N, 061°10ʹ24ʺ W], lower rio Branco basin, 19-VII-2008, coll. J.D. do Vale; 8 males, 18 females (4 ovig.) ( INPA 2360), Caracaraí, Caicubi, igarapé Canuini, 01°00ʹ33.1ʺ S, 061°55ʹ13.3ʺ W, tributary of rio Jufari, lower rio Branco basin, 11-VI-2013, coll. F.C. Zanetti; 2 males, 12 females (6 ovig.) ( INPA 2330), Caracaraí, Terra Preta, igarapé Marixi, 00°50ʹ52.916ʺ N, 061°57ʹ51.778ʺ W, tributary of rio Xeriuini, lower rio Branco basin, 25-III-2014, colls. M.A.L. Santos and F.C. Zanetti; 63 spec. ( INPA 2324), Caracaraí, Terra Preta, rio Xeriuini, 00°33ʹ54.731ʺ N, 061°57ʹ9.945ʺ W, lower rio Branco basin, 25-III-2014, colls. M.A.L. Santos and F.C. Zanetti.

Distribution. Venezuela, Colombia, Brazil [Amazonas, Amapá, Pará, Roraima [new record]), Peru (see Pimentel and Magalhães 2014 for references; present study). The distribution in Roraima is depicted in Figure 7.

Remarks. The morphology of our specimens agrees quite well with the description provided by Kensley and Walker (1982), García-Dávila and Magalhães (2003) and Melo (2003). No significative intraspecific variability was noticed.