Sunday, April 10, 2022

[Ichthyology • 2022] Eigenmannia bumba, E. cacuria & E. robsoni • Three New Species of Eigenmannia (Gymnotiformes: Sternopygidae) from the rio Mearim and rio Parnaíba basins, Northeastern Brazil


Eigenmannia bumba (white), E. cacuria (black),
and E. robsoni (red). A star indicates the type locality.


Dutra, Ramos & Menezes, 2022

Abstract​ 
Three new species of Eigenmannia belonging to the E. trilineata species-group are described. The first species is described from rio Mearim basin and can be diagnosed by lateral line stripe restricted to last two thirds of body, superior midlateral stripe present, 176–205 anal-fin rays, 10–15 scales rows above lateral line, 109–125 lateral line scales, 19–23 premaxillary teeth, 20–29 dentary teeth, 6–10 endopterygoid teeth, and 13–14 precaudal vertebrae. The second species is described from upper rio Parnaíba, and can be diagnosed by lateral line stripe restricted to last two-thirds of body, ii,11–13 pectoral-fin rays, 180–196 anal-fin rays, 12–15 scales rows above lateral line, 10–14 premaxillary teeth, 15–21 dentary teeth, 8–10 endopterygoid teeth, and 14 precaudal vertebrae. The third species is widespread in rio Parnaíba basin, and can be diagnosed by absence of lateral line stripe, absence of superior midlateral stripe, 182–228 anal-fin rays, 12–15 scales rows above lateral line, 107–131 lateral line scales, 32–34 premaxillary teeth, 35–44 dentary teeth, 9–12 endopterygoid teeth, and 13 precaudal vertebrae. A dichotomous key and the conservation status for the three species are provided.

Keywords: Electric fishes, Eigenmannia trilineata species-group, Identification key, Taxonomy.


Map of Northern Brazil showing distribution of Eigenmannia bumba (white), Eigenmannia cacuria (black), and E. robsoni (red). A star indicates the type locality.

Eigenmannia bumba, MZUSP 125870, holotype, 117.5 mm LEA, 
rio Santana, Grajaú, Maranhão, Brazil. 
A. lateral view of head, B. lateral view of body.

Eigenmannia cacuria, MZUSP 125871, 
holotype, 110.0 mm LEA, 
riacho Enxada, Alto Parnaíba, Maranhão. 
A. lateral view of head, B. lateral view of body.

Eigenmannia bumba, new species

Etymology. The epithet “bumba” is in reference to “bumba meu boi” or “boi-bumbá”, a folklore character in Northern Brazil. A noun in apposition.


Eigenmannia cacuria, new species

Etymology. The epithet “cacuria” is in reference to the “cacuriá”, a typical dance in the state of Maranhão, where the holotype was collected. A noun in apposition.


Eigenmannia robsoni, MZUSP 125872, holotype, 139.3 mm LEA,
rio Parnaíba, Muricí dos Portelas, Piauí.
A. lateral view of head, B. lateral view of body.

Eigenmannia robsoni, new species

Etymology. The epithet “robsoni” is in honor of Robson Tamar da Costa Ramos, ichthyologist, for his contributions to studies of the Caatinga ecoregion, especially in the Parnaíba river basin. A patronym.


 Guilherme Moreira Dutra, Telton Pedro Anselmo Ramos and  Naércio Aquino Menezes. 2022. Description of Three New Species of Eigenmannia (Gymnotiformes: Sternopygidae) from the rio Mearim and rio Parnaíba basins, Northeastern Brazil. Neotrop Ichthyol. 20(1);e210117.  DOI: 10.1590/1982-0224-2021-0117