Costa & De Luca, 2011
Rivulus schuncki, a new species of the killifish subgenus Melanorivulus, from eastern Brazilian Amazon (Cyprinodontiformes: Rivulidae)Rivulus schuncki, new species, is described from the Anauerapucu River drainage, lower Amazonas River basin, northern Brazil. It is distinguished from all other species of the subgenus Melanorivulus by its pointed snout in lateral view, 12 rows of scales around the caudal peduncle, bright green bars on the flank and caudal fin in males, flank dark brown with small light gray spots on ventral part in females, pelvic fin without dark gray or black anterior margin in females and by the absence of red bars or dots arranged in chevron-like pattern on flank. Rivulus schuncki constitutes the first record of the subgenus Melanorivulus north of the Amazonas River.
Wilson J. E. M. Costa and Andre C. De Luca
Ichthyological Exploration of Freshwaters, Vol. 21, No. 4, pp. 289-293, 2010