Diversity, distribution and new records of freshwater and estuarine shrimp in the state of Amapá, eastern Brazilian Amazon region Author Vieira, Inacia Maria 0000-0002-6911-0780 Programa de Pós-Graduação em Biodiversidade e Biotecnologia (BIONORTE), Universidade Federal do Amapá, Macapá, AP, Brasil. Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá - IEPA. & inaciavieira 2011 @ gmail. com; https: // orcid. org / 0000 - 0002 - 6911 - 0780 inaciavieira2011@gmail.com Author Silva, Luiz Maurício Abdon Programa de Pós-Graduação em Biodiversidade e Biotecnologia (BIONORTE), Universidade Federal do Amapá, Macapá, AP, Brasil. Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá - IEPA. Author Almeida, Alini Gomes Santiago De 0000-0002-9773-489X alinigsantiago @ gmail. com; https: // orcid. org / 0000 - 0002 - 9773 - 489 X alinigsantiago@gmail.com Author Almeida, Danilo Pelaes De Programa de Pós-Graduação em Ciências Ambientais, Universidade Federal do Amapá, Macapá, AP, Brasil. Author Silva-Júnior, Orleno Marques 0000-0002-1173-1429 orlenomarques @ yahoo. com. br; https: // orcid. org / 0000 - 0002 - 1173 - 1429 orlenomarques@yahoo.com.br Author Tavares-Dias, Marcos Programa de Pós-Graduação em Biodiversidade e Biotecnologia (BIONORTE), Universidade Federal do Amapá, Macapá, AP, Brasil. Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá - IEPA. & Embrapa Amapá, Macapá, AP, Brasil. text Zootaxa 2022 2022-08-24 5178 1 41 71 journal article 129872 10.11646/zootaxa.5178.1.3 6329ab0a-3a78-4998-aae3-bf28b87876bb 1175-5326 7021864 4DECF608-22E1-4049-9271-F20E5E0ECB49 Euryrhynchus tomasi De Grave, 2007 Examined material. Municipality of Calçoene : tributary stream on the right bank of the Amapá Grande River , downstream of Cachoeira Grande , Calafate ( 2°9’30.98”N , 50°55’19.83”W ), 22.ix.2021 , colls. I.M. Vieira and A.G.S. de Almeida and D.P. de Almeida , 14 males and 5 females ( IEPA 2099 ) . Geographic distribution. French Guiana , Brazil ( Amapá state , northwest and north of the city of Amapá , Vilarejo and Balneário Cachoeira Grande, Amapá Grande River and Cachoeira Grande, according to De Grave (2007) and Pachelle & Tavares (2018) ( Figure 1 ). Distribution in Amapá state . Affluent stream of the Amapá Grande River, downstream and upstream of Cachoeira Grande. Previous records. Pachelle & Tavares (2018) Ecological notes. Collected in shallow and shaded stream, with plenty of leaf litter, dry season, pH (6.08), water temperature (25.5°C), dissolved oxygen (60.7%) and conductivity (10 μS/cm). Remarks. Euryrhynchus tomasi is distinguished from E. burchelli by presenting the pereiopod carpus 2 unarmed and the grouper with a spine on each side of the distoventral region; while females have an internal appendage from the third to the fifth pleopod (Pachelle & Tavares 2018).