Macrobrachium jelskii ( Miers, 1877 )

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 : 27-28

Macrobrachium jelskii ( Miers, 1877) ( Figs 3L–N, 8)

Previous records. Cavalcante and Castro (2014).

Identification characters ( Fig. 3L–N). Rostrum long, slender, straight over the eyes, distal portion curved upwards, reaching a little beyond the scaphocerite; rostral formula: 7–10(1 post-orbital tooth)/5–7. Carapace with antennal and hepatic teeth present, otherwise smooth; abdomen smooth, pleura of second somite enlarged and overlapping pleuron of first and third somites. Telson with posterior margin distinct, ending in a small acute point, overreached by inner pair of posterolateral spines. P2 (larger cheliped) similar in shape and size.

Material examined. 1 male ( INPA 2384), Boa Vista, rio Cauamé, 02°51ʹ00.7ʺ N, 060°37ʹ49.7ʺ W, 04-XII-2014, colls. M.A.L. Santos and I. R.S. Almeida; 3 females, 6 immat. spec. ( INPA 2348), Cantá, unnamed igarapé, tributary of rio Branco, 02°43ʹ15.5ʺ N, 060°37ʹ48.9ʺ W, 15-XII-2006, coll. F.A.G. Melo; 4 males, 45 females (4 ovig.) ( INPA 2327), Mucajaí, Tamandaré, rio Mucajaí, 02°33ʹ48.2ʺ N, 060°55ʹ43.8ʺ W, 12-II-2015, colls. F.C. Zanetti and S.C. Emídio.

Distribution. Trinidad, Venezuela, Guyana, Suriname, French Guiana, Brazil (Acre, Amazonas, Amapá, Alagoas, Bahia, Ceará, Espírito Santo, Maranhão, Mato Grosso, Minas Gerais, Pará, Paraíba, Paraná, Pernam- buco, Rio de Janeiro, Rio Grande do Norte, Roraima, São Paulo, Sergipe), Peru, Bolivia, Argentina ( Cavalcante and Castro 2014; see Vera-Silva et al. 2017 for references; present study). The distribution in Roraima is depicted in Figure 8.

Remarks. The morphology of our specimens agrees very well with the description provided by Holthuis (1952), García-Dávila and Magalhães (2003), and Melo (2003). Adult specimens of M. jelskii and M. amazonicum can be easily distinguished by the shape of the rostrum and telson, although juveniles and subadults are somewhat difficult to separate. Vera-Silva et al. (2017) presented a set of characters to differentiate both species.