Plesiolebias altamira

description

Description. Morphometric data appear in Table 2. Largest male examined 17.5 mm SL, largest female 18.1 mm SL. Dorsal profile slightly convex from snout to end of dorsal-fin base, approximately straight on caudal peduncle. Ventral profile gently convex from lower jaw to end of anal-fin base, nearly straight on caudal peduncle. Body moderately slender, compressed. Greatest body depth at level of pelvic-fin base. Jaws short, snout blunt. Tip of dorsal and anal fins rounded. Caudal fin rounded. Pectoral fins elliptical, posterior margin reaching vertical through base of 2 nd anal-fin ray in males, through anus in females. Pelvic fins pointed in males, terminating in long filament, with tip reaching base of 9 th anal-fin ray; tip of each pelvic fin reaching urogenital papilla in females. Pelvic-fin bases medially united. Dorsal-fin origin on vertical through base of 4 th or 5 th anal-fin ray, and between neural spines of 11 th and 12 th vertebrae. Anal-fin origin between pleural ribs of 9 th and 11 th vertebrae. Dorsal-fin rays 10 – 12; anal-fin rays 14 – 16; caudal-fin rays 23 – 25; pectoral-fin rays 12 – 13; pelvic-fin rays 8. Scales large, cycloid. Body and head entirely scaled, exc

Taxonomy of the plesiolebiasine killifish genera Pituna, Plesiolebias and Maratecoara (Teleostei: Cyprinodontiformes: Rivulidae), with descriptions of nine new species

diagnosis

Diagnosis. Distinguished from all its congeners by the combination of the following characters: filamentous ray present on each pelvic fin in males (vs. filamentous ray absent); pelvic-fin rays 8 (vs. 7); eye yellow in males (vs. bright green); flank with oblique black bars in males (vs. black bars absent); red stripe on anterior portion of flank not anteriorly reaching orbit in males (vs. red stripe reaching orbit or absent); basal portion of dorsal fin red in males (vs. with transverse rows of dark red and white spots); a black spot on posterior portion of anal fin in males (vs. black spot absent); body depth 24.8 – 25.6 % SL in males, 23.0 – 26.0 % SL in females (vs. 28.6 – 32.6 % SL in males, 26.4 – 30.3 % SL in females); sparse bright dots on flank in males (vs. oblique rows of bright dots on flank); 3 white bars on basal portion of anal fin in males (vs. 4 – 5); a black bar on preopercle (vs. black bar absent); 8 – 9 oblique bars on flanks in females (vs. 5 – 7); 22 – 23 scales in longitudinal series (vs. 24 – 25).

Taxonomy of the plesiolebiasine killifish genera Pituna, Plesiolebias and Maratecoara (Teleostei: Cyprinodontiformes: Rivulidae), with descriptions of nine new species

distribution

Distribution and habitat. Known only from seasonal pools near the city of Altamira, rio Xingu drainage, rio Amazonas basin, Estado do Pará, Brazil (Fig. 13).

Taxonomy of the plesiolebiasine killifish genera Pituna, Plesiolebias and Maratecoara (Teleostei: Cyprinodontiformes: Rivulidae), with descriptions of nine new species

etymology

Etymology. The name altamira is an allusion to the occurrence of the new species near the city of Altamira, Brazilian Amazon.

Taxonomy of the plesiolebiasine killifish genera Pituna, Plesiolebias and Maratecoara (Teleostei: Cyprinodontiformes: Rivulidae), with descriptions of nine new species