Melanorivulus linearis

description

Description Morphometric data appear in Table 3. Body relatively deep, sub-cylindrical anteriorly, deeper than wide, compressed posteriorly. Greatest body depth at vertical just anterior to pelvic-fin base. Dorsal and ventral profiles of trunk slightly convex in lateral view; dorsal and ventral profiles of caudal peduncle nearly straight. Head moderately wide, sub-triangular in lateral view, dorsal profile nearly straight, ventral profile convex. Snout blunt. Jaws short; teeth numerous, conical, irregularly arranged; outer teeth hypertrophied, inner teeth small and numerous. Vomerine teeth 3 - 5. Gill-rakers on first branchial arch 1 + 8. Dorsal and anal fins short, tip slightly pointed in males, rounded in females. Caudal fin rounded, slightly longer than deep. Pectoral fin rounded, posterior margin reaching vertical just anterior to pelvic-fin insertion. Pelvic fin small, longer in males, tip reaching between base of 2 nd or 3 rd anal-fin ray in males, reaching between anus and urogenital papilla in females; pelvic-fin bases medially in close proximity. Dorsal-fin origin on vertical through base of 8 th or 9 th anal-fin ray. Dorsal-fin rays 10 - 11; anal-fin rays 13 - 15; caudal-

Three new species of the killifish genus Melanorivulus from the Rio Parana Basin, central Brazilian Cerrado (Cyprinodontiformes, Aplocheilidae)

diagnosis

Diagnosis Melanorivulus linearis is similar to M. egens, and distinguished from all other species of the M. pictus group by the presence of red chevron-shaped marks regularly distributed on the flank (vs. irregularly), absence of distinctive dark marks on humeral region (vs. presence), and absence of red dots on the anteroventral portion of flank (vs. presence). Melanorivulus linearis is distinguished from M. egens by the presence of red bars restricted to the dorsal portion of the caudal fin in males (vs. absence), presence of black bars on the caudal fin in females (vs. black dots); presence of a pale green spot on humeral region in males (vs. absence); and second proximal radial of the dorsal fin between neural spines of 18 th and 19 th vertebrae (vs. between neural spines of 19 th and 21 st vertebrae).

Three new species of the killifish genus Melanorivulus from the Rio Parana Basin, central Brazilian Cerrado (Cyprinodontiformes, Aplocheilidae)

distribution

Distribution Known only from the type locality, upper section of the Rio Pardo, middle Rio Parana Basin, central Brazil (Fig. 3).

Three new species of the killifish genus Melanorivulus from the Rio Parana Basin, central Brazilian Cerrado (Cyprinodontiformes, Aplocheilidae)

etymology

Etymology From the Latin, linearis (consisting of lines), an allusion to the red oblique lines regularly arranged on the flank in males.

Three new species of the killifish genus Melanorivulus from the Rio Parana Basin, central Brazilian Cerrado (Cyprinodontiformes, Aplocheilidae)