Melanorivulus Costa 2006
Creators: name: Ota, Renata Rúbia
name: Deprá, Gabriel de Carvalho
name: Graça, Weferson Júnio da
name: Pavanelli, Carla Simone
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Cyprinodontiformes
Rivulidae
Melanorivulus

description: <i>Melanorivulus</i> sp. <b>Fig. 36</b> Body elongated; greatest depth contained 4.1 to 4.6 and caudal peduncle depth 6.3 to 7.2 times in SL; head length 3.6 to 3.9, predorsal distance 1.2 to 1.3, prepelvic distance 1.7 to 1.9; dorsal-fin base length 8.6 to 10.0, anal-fin base length 4.2 to 5.1 and head width 4.6 to 5.1 times in SL; horizontal orbital diameter 2.8 to 3.3 in HL. Mouth terminal, premaxilla and dentary with several small teeth. Longitudinal series with 29-31 scales and transverse series with 8 or 9 scale rows. Dorsal fin with 8 or 9, pectoral fin with 11 or 12, pelvic fin with 6 or 7 and anal fin with 13-15 rays. Males with ground color greyish or pale brown, with dark-brown oblique and irregular stripes, V-shaped (its vertex turned forward); dark-brown transverse stripes on opercle; dorsal, anal and caudal fins with dark-brown transverse stripes. Females with similar color pattern, besides dark-brown rounded blotch on caudal-fin base. <b>Maximum standard length.</b> 25.0 mm. <b>Distribution.</b> Upper rio Paraná basin. <b>Remarks.</b> <i>Melanorivulus</i> sp. was identified as <i>Rivulus apiamici</i> by Graça, Pavanelli (2007). Costa (2011) included all species of the former <i>Rivulus punctatus</i> Boulenger, 1895 species complex in the genus <i>Melanorivulus</i> Costa, 2006, one of which is <i>M. apiamici</i> (Costa 1989). Recently, Nielsen (2016) restricted the distribution of <i>M. apiamici</i> to the right bank of the upper rio Paraná, between Bataguassu and Três Lagoas, State of Mato Grosso do Sul. According to literature, the only two species known from the upper rio Paraná floodplain are the recently described Melanorivulus amambaiensis Volcan, Severo-Neto, Lanés 2018 and <i>M. ivinhemensis</i> Volcan, Severo-Neto, Lanés 2018. We analyzed preserved specimens from the rio Ivinhema (NUP 9350) and rio Amambaí (NUP 17575) basins, as well as from other localities in the upper rio Paraná floodplain (NUP 10022 and 12082). The specimens from these lots have 22-26 total caudal-fin rays, which is close to the counts recorded for <i>M. amambaiensis</i> in the original description, and less than the counts recorded for <i>M. ivinhemensis</i>. In fact, <i>Melanorivulus</i> specimens from other nearby localities available to us also show overlapping counts: from the rio Verde basin (NUP 6217), 24-30 rays; from the lower rio Paranapanema basin (NUP 6060, 6075, 7598), 22-28 rays. Thus, we prefer to use <i>Melanorivulus</i> sp. until more information, such as color pattern in life, is available.
description: Published as part of <i>Ota, Renata Rúbia, Deprá, Gabriel de Carvalho, Graça, Weferson Júnio da &amp; Pavanelli, Carla Simone, 2018, Peixes da planície de inundação do alto rio Paraná e áreas adjacentes: revised, annotated and updated, pp. 1-111 in Neotropical Ichthyology 16 (2)</i> on page 99, DOI: 10.1590/1982-0224-20170094, http://zenodo.org/record/3678395
description: {"references": ["Pavanelli CS, Graca WJ, Zawadzki CH, Britski HA, Vidotti AP, Avelino GS, Verissimo S. Fishes from the Corumba Reservoir, Paranaiba River drainage, upper rio Parana basin, State of Goias, Brazil. Check List. 2007; 3 (1): 58 - 64.", "Costa WJEM. Phylogenetic position and taxonomic status of Anablepsoides, Atlantirivulus, Cynodonichthys, Laimosemion and Melanorivulus (Cyprinodontiformes: Rivulidae). Ichthyol Explor Freshw. 2011; 22 (3): 233 - 49.", "Nielsen DTB, Neves PABA, Ywamoto EV, Passos MA. Melanorivulus polychromus, a new species of killifish from the rio Sao Jose dos Dourados drainage, middle rio Parana basin, southwestern Brazil, with a redescription of Melanorivulus apiamici Cyprinodontiformes: Rivulidae). Aqua. 2016; 22 (2): 79 - 88."]}