3
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Unrecognized biodiversity in a world’s hotspot: three new species of Melanorivulus (Cyprinodontiformes: Rivulidae) from tributaries of the right bank of the Rio Paraná basin, Brazilian Cerrado

      , ,

      Zoosystematics and Evolution

      Pensoft Publishers

      Read this article at

      ScienceOpenPublisher
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          The genus Melanorivulus presents a wide geographical distribution in the Neotropical region. Among Melanorivulus, the M. pictus species group has currently 18 species distributed in the Brazilian Cerrado, mainly in the upper Rio Paraná basin, with some species occurrences in the upper Rio Araguaia and Tocantins. In the present study, we describe three new Melanorivulus species, belonging to the M. pictus species group from different drainages of the right bank of the Rio Paraná basin in Mato Grosso do Sul state, Brazil. These new species are easily distinguished from the others by their unique colour patterns. Melanorivulus interruptus is distinguished from all species of the M. pictus group by the presence of oblique chevron-like red bars interrupted, mainly on the midline of the flank in males; while M. ivinhemensis by the yellow colouration of the caudal fin with thin red bars arranged only in the median region of the fin in males. Melanorivulus amambaiensis is distinguished from all species of the M. pictus species group by having an orange anal fin or sometimes more reddish-orange with distal margin grey or dark grey and chevron-like bars along the body, distinctly branched ventrally forming an inverted Y-shape in males. The high diversity of the Melanorivulus species with high levels of endemism demands the development of conservation strategies to avoid the loss of their vulnerable habitats in the Cerrado biome. We expect presence of more species of the M. pictus species group also along the lower reaches of the tributaries of the Rio Paraná. Additionally a dichotomic identification key of the M. pictus species group is provided.

          Related collections

          Most cited references 6

          • Record: found
          • Abstract: not found
          • Article: not found

          The Brazilian Cerrado Vegetation and Threats to its Biodiversity

           J. A. RATTER (1997)
            Bookmark
            • Record: found
            • Abstract: found
            • Article: found
            Is Open Access

            Seven new species of the killifish genus Rivulus (Cyprinodontiformes: Rivulidae) from the Paraná, Paraguay and upperAraguaia river basins, central Brazil

             Wilson Costa (2005)
            Seven new species of the Rivulus punctatus group collected during recent field studies in central Brazil are described. Rivulus dapazi n. sp., from the upper rio Correntes drainage, rio Paraguay basin, is diagnosed by a unique color pattern of the anal and caudal fins in males; R. cyanopterus n. sp., from the upper rio São Lourenço drainage, rio Paraguay basin, is diagnosed by a unique color pattern of the anal fin in both sexes; R. rossoi n. sp., from the rio Inhanduí drainage, rio Paraná basin, is diagnosed by a unique color pattern of the caudal fin in males and a reduced number of gill rakers on the first branchial arch; R. litteratus n. sp., from the upper rio Araguaia basin, is diagnosed by unique color patterns of flank in males and caudal fin in females; R. rutilicaudus n. sp., from the rio Verde drainage in Goiás, rio Paraná basin, is diagnosed by a unique color pattern of the caudal fin in females; R. scalaris n. sp., from the rio Sucuruí, rio Aporé, rio Correntes and rio Taquari drainages, rio Paraná basin, is diagnosed by a unique color pattern of the flank in males; and, R. egens n. sp., from the upper rio Verde drainage in Mato Grosso do Sul, rio Paraná basin, is distinguished by a combination of frontal E-scale pattern and the absence of red marks on the caudal fin in males. Combinations of other color patterns and morphological features, including number of scales of the longitudinal series, number of dorsal, anal, caudal and pectoral fin-rays, relative position of dorsal-fin origin and anal-fin rays, and number of vertebrae, are also useful in identification of the new species, but phylogenetic relationships among them are unknown at the present. A key to identification of species of Rivulus from the rio Paraná-Paraguay basin and adjacent headstreams is provided.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Two new species of Melanorivulus (Cyprinodontiformes: Cynolebiidae) from Rio Verde drainage, Upper Rio Paraná basin, Brazil

              Two new species of the genus Melanorivulus are herein described from the middle Rio Verde drainage, upper Rio Paraná basin, Mato Grosso do Sul, Brazil. Both new species are members of the Melanorivulus pictus clade, diagnosed by having ventral process of angulo-articular vestigial and flanks intense greenish blue or greenish golden to purplish blue above anal fin base in males. Melanorivulus nigropunctatus, new species, from wetlands of a small drainage tributary of right side of the Rio Verde, differs from all other congeners by possessing black dots over the head and body in both sexes and pectoral fin orange with a dark grey margin in males. Melanorivulus ofaie, new species, is found in a similar environment, but at the opposite margin of the Rio Verde. It is distinguished by males presenting flank greenish blue to light blue, with seven to nine oblique chevron-like red bars, ventral portion of head whitish with dark brown spots, dorsal fin yellow with two to three transverse broad red oblique stripes and distal region red, anal fin light orangish yellow, basal area light blue with short red bars and distal portion with a dark red margin, and caudal fin yellow or orangish yellow with three to four vertical red bars in the dorsal and middle portions, sometimes with a orange distal margin. Both new species are considered endangered due to the loss and degradation of their habitat.
                Bookmark

                Author and article information

                Journal
                Zoosystematics and Evolution
                ZSE
                Pensoft Publishers
                1860-0743
                1435-1935
                April 18 2018
                April 18 2018
                : 94
                : 2
                : 263-280
                Article
                10.3897/zse.94.24406
                © 2018

                Comments

                Comment on this article