Monday, November 21, 2016

[Ichthyology • 2013] Spectrolebias brousseaui • A New Annual Fish (Cyprinodontiformes: Rivulidae: Cynolebiatinae) from the upper río Mamoré basin, Bolivia


Spectrolebias brousseaui  
Nielsen, 2013 
  DOI: 
10.1590/S1679-62252013000100009  

ABSTRACT

Spectrolebias brousseaui is described from a temporary pool from the upper río Mamoré basin, Departamento Santa Cruz, Bolivia. The new species is distinguished from all congeners, by the overall dark blue coloration on the posterior two-thirds of body with bright blue iridescent spots vertically aligned in males. Spectrolebias brousseaui differs from all other species of the genus, except S. filamentosus, for having pelvic fins separated by a space (vs. pelvic fins in contact), long filaments at the tip of the dorsal and anal fins in males (vs. absence of filaments or presence only on dorsal fin in S. semiocellatus and S. inaequipinnatus, or the presence on the anal fin in S. chacoensis), and presence of contact organs on the scales of the flanks in males (vs. absence of contact organs on flanks in all remaining Spectrolebias species).

Key words: Phylogeny; Spectrolebias filamentosus; Temporary pool




Distribution. Known from the type locality in río San Pablo basin, a tributary of the río Mamoré, Departamento Santa Cruz, Bolivia.

Habitat. The type locality lies at the plateau area (316 m.a.s.l.), just southwest of Llanos de Mojos, which occupy much of the río Mamoré basin in Bolivia (see Loubens et al., 1992). Water temperature at the surface of the pool was 31ºC, while at the depth of 1 m, 22ºC. In the marginal area of the pool, at the depth of 15 cm, water temperature was 35ºC. Only small specimens of Trigonectes sp. were collected in marginal areas. Specimens of Simpsonichthys brousseaui were collected in the deepest areas, at about 1 m deep. The pool presented dark water, pH 6.8 and water hardness 80 ppm. Other fish species collected syntopically were Trigonectes sp.

Etymology. The specific name is in honor to Roger D. Brousseau, discoverer of the species.


Nielsen, D.T.B. 2013. Spectrolebias brousseaui (Cyprinodontiformes: Rivulidae: Cynolebiatinae), A New Annual Fish from the upper río Mamoré basin, Bolivia.
 Neotropical Ichthyology. 11(1); 81-84.  DOI: 10.1590/S1679-62252013000100009 



RESUMO: Spectrolebias brousseaui é descrita de uma poça temporária localizada na região superior da bacia do río Mamoré, departamento de Santa Cruz, Bolívia. A espécie nova distingue-se de todos os congêneres pelo padrão de cor azul escuro nos dois terços posteriores do corpo com pontos azuis claros iridescentes alinhados verticalmente em machos. Spectrolebias brousseaui difere das outras espécies do gênero, exceto S. filamentosus, por ter as nadadeiras pélvicas separadas por um espaço (vs. nadadeira pélvicas juntas), longos filamentos nas extremidades das nadadeiras dorsal e anal em machos (vs. ausência de filamentos ou a presença apenas na nadadeira dorsal em S. semiocellatus e S. inaequipinnatus, ou pela presença de filamentos na nadadeira anal em S. chacoensis), e presença de órgão de contato nas escamas do flanco em machos (vs. ausência)