Macrobrachium carcinus Linnaeus, 1758

Examined material. Municipality of Macapá: District Fazendinha, Amazon River (00°03’18.89”S, 51°07’09.40”W), 26.v.1990, J.C.S. de Oliveira, 1 male and 1 female (IEPA 10) ; idem, 26.v.1990, coll. J.C.S. de Oliveira, 01 specimen (IEPA 11); idem, 25.v1990, coll. J.C.S. de Oliveira, 03 males and 01 females with eggs (IEPA 13); idem, 25.v1990, coll. J.C.S. de Oliveira, 1 female with eggs (IEPA 14); idem, 1 male (IEPA 15); idem, 06.v.1990, coll. J.C.S. de Oliveira, 1 female with eggs (IEPA 16); idem, 06.v.1990, J.C.S. de Oliveira, 03 females and 1 female with eggs (IEPA 17); Archipelago of Bailique, Faustino River (00°53’36.9”N, 50°11’01.9”W), 31.viii.1995, L. Ramos H.P. Belo, J.O. Cardoso and I.M. Vieira, 1 male (IEPA 48) ; idem, 01 female (IEPA 49); idem, Amazon River (00°52’59.34”N, 50°04’56.51”W), 23.vi.2000, I.M. Vieira, O.A. Alencar and O.M. Costa, 1female with eggs (IEPA 221) .— Municipality of Santana: Igarapé Fortaleza River (00°38’40.55”N, 52°30’30.71”W), 4.ii.1997, O.M. Costa, 02 males and 01 female (IEPA 125) ; idem, (0°02’42.01”S, 51°08’10.38”W), 10.xi.1998, I.M. Vieira, 1 male (IEPA 824); Santana Island, Amazon River (00°05’13.84”S, 51°09’06.98”W), 15.iv.2000, I.M. Vieira, O.A. Alencar O.M. Costa and J.O. Cardoso, 04 females (IEPA 208) , Santana Island, Dourado Lake (00°04’32.2”S, 1°09’44.4W), 21.iv.2012, A.G. Santiago and E.O. Galeno, 1 male (IEPA1561) ; idem, Amazon River, Recanto da Aldeia (00°04’43.8”S, 51°09’53.7”W), 15.viii.2012, A.G. Santiago and E.O. Galeno, 1 male (IEPA 1576) , idem, Amazon River, Recanto da Aldeia (00°04’43.8”S, 51°09’53.7”W), 16.xi.2012, A.G. Santiago and E.O. Galeno, 2 males and 2 females (IEPA 1588) ; idem, Amazon River, Praia da Ponte (00°02’318.0”S, 51°05”38.7”W), 27.x.2012, A.G. Santiago and E.O. Galeno, 2 males (IEPA 1587) . Municipality of Pracuúba: Pracuúba Lake (1°45’01.21”N, 50°49’15.40”W), 18.xi.1990, J.C.S. Oliveira, 2 males and 3 females (IEPA 258) (Figure 3).

Geographic distribution. Eastern Atlantic Ocean, USA (Florida, Mississipi, Louisiana and Texas) Mexico, Cuba, Guatemala, Costa Rica, Panamá, Cuba, Porto Rico, Jamaica, Barbados, Lesser Antilles, Colombia, Ecuador, Peru, Venezuela, Guyana, Suriname and Brazil (states of Pará, Pernambuco, Alagoas, Espírito Santo, Rio de Janeiro, São Paulo, Santa Catarina and Rio Grande do Sul) (Ferreira et al. 2010; Holthuis 1952; Melo 2003; Pimentel & Magalhães 2014; (Delgado et al. 1997; Ramos-porto & Coelho 1998; Bowles et al. 2000).

Distribution in Amapá state. Amazon River (Fazendinha, Archipelago of Bailique, Santana Island); Faustino River (tributary of the Araguari River) and Pracuúba Lake.

Previous records. Pimentel & Magalhães (2014)

Ecological notes. The shrimp of the species inhabit backwaters in rivers with strong turbulence; under trunks and rocks, nocturnal, found in rivers of the Atlantic drainage.

Remarks. The species can reach 300 mm in body length and weigh up to 1 kg, while ovigerous females generally range from 130–170 mm. The carpus of the second pair of pereiopods is clearly shorter than the mere (Bowles et al. 2000)