New cave catfish discovered in Brazil


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A new species of cave trichomycterid catfish has been described from central Brazil by Brazilian catfish experts Maria Bichuette and Eleonora Trajano.

The new species, named Ituglanis mambai, is described from a cave in the Mamba karst area in Gois State, Central Brazil in the latest issue of the journal Neotropical Ichthyology.

Ituglanis mambai is distinguished from other members of the genus in having a combination of: posterior fontanel absent; usually i,7 pectoral-fin rays; six pleural ribs; 37"38 vertebrae posterior to the Weberian apparatus; shorter predorsal length (65.1"70.8% standard length); shorter caudal peduncle (8.4"11.9% standard length); shorter dorsal-fin base (7.7-11.3% standard length); larger interorbital width (29.2"36.5% head length); wider mouth (43.4"64.0% head length); pigmentation intermediate in form between epigean and cave congeners and composed of irregular light brown spots along the body; eye size variable and intermediate between those of epigean and subterranean congeners (diameter 7.8-10.1 % head length).

The new species is named after its type locality.

The authors have the following to say about its ecology: he stream reach where the fishes were observed is characterized by slow to fast-moving waters, 10-90 cm deep on average, and bottom formed basically by sand, silt, some gravels and boulders...

Environmental variables measured in September 2004: water temperature, 23.4C; pH, 7.9; conductivity, 0.141 S/cm; dissolved oxygen, 7.4 mg/l.

The catfishes were observed to be solitary, swimming mostly on the bottom and sometimes in midwater.

Ituglanis mambai displayed a strong aversion to light and tried to burrow into the substrate or hide amongst crevices under boulders when disturbed. They also showed a preference for slow-moving pools.

No images of Ituglanis mambai were available for publication.

For more information, see the paper: Bichuette, ME and E Trajano (2008) Ituglanis mambai, a new subterranean catfish from a karst area of Central Brazil, rio Tocantins basin (Siluriformes: Trichomycteridae). Neotropical Ichthyology 6, pp. 9"15.