Avaliação do status taxonômico de Moenkhausia colletti (Steindachner, 1882) e Moenkhausia copei (Steindachner, 1882) (Characiformes: Characidae)

Abstract

Two species of the genus Moenkhausia (Eigenmann, 1903) are reviewed, and two related new species were described by analyses of syntypes photographs, original descriptions, and analysis of material deposited in ichthyologycal collections, besides fresh material caught in type localities. Redescriptions were made based on morphometrics, meristics and osteological data, and colorpatterns. At all, 472 specimens were examined, and four species were recognized: Moenkhausia collettii (Steindachner, 1882), Moenkhausia copei (Steindachner, 1882) and two new taxon, Moenkhausia sp. n. A and Moenkhausia sp. n. B . The four species are similar to the presence of a longitudinal strip which runs along the middle portion of the eye, a dark band in the longitudinal anal fin base, a dark band along the longitudinal length of the body and a conspicuous humeral spot. In Moenkhausia collettii and Moenkhausia sp. n. "B", the longitudinal strip along the length of the body is clear; covering a row of scales, while in Moenkhausia copei and Moenkhausia sp. n. "A" longitudinal stripe along the length of the body is more marked, covering two rows of scales. In Moenkhausia collettii and Moenkhausia copei, the longitudinal band at the base of the anal fin is clear, starting at the base of the first ray unbranched anal fin and ending at the base of the last ray branched fin, whereas in Moenkhausia sp. n. "A" and Moenkhausia sp. n. "B" the longitudinal band at the base of the anal fin is more marked, starting approximately three scales before the first ray unbranched and ending on the base of the last ray branched anal fin. Moenkhausia collettii, Moenkhausia copei and Moenkhausia sp. n. "B" share the presence of 5 series of scales above lateral line (vs. 6 series of scales above lateral line in Moenkhausia sp. n. "A"). Moenkhausia collettii and Moenkhausia copei share the presence of 3 series of scales below the lateral line (vs. 4 series of scales below the lateral line in Moenkhausia sp. n. "A" and Moenkhausia sp. n. "B"). Moenkhausia sp. n. "A" differs from Moenkhausia collettii, Moenkhausia copei and Moenkhausia sp. n. "B" by the presence of heptacuspid teeth in the inner series of premaxilla and dentary (vs. pentacuspid teeth in the inner series of pre-maxilla and dentary in Moenkhausia collettii, Moenkhausia copei and Moenkhausia sp. n. "B"). The four species are included in the Moenkhausia lepidura group. For all species are presented diagnosis, description or redescription, sexual dimorphism, color in alcohol, geographical distribution and remarks.