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| Scobinancistrus raonii Chaves, de Oliveira, Gonçalves, Sousa & Rapp Py-Daniel, 2023 Photos: Leandro M. Sousa and Mark H. Sabaj |
Abstract
A new species of Scobinancistrus from the Xingu River, Brazil, is described. It can be distinguished from its congeners by color pattern and a combination of non-exclusive characters: overall body covered by large yellow spaced blotches over a dark background (vs. small round and densely packed spots over light or dark background in S. pariolispos and S. aureatus); lack of orange to yellow/orange distal band on dorsal and caudal fins (vs. presence in S. aureatus), dorsal fin not reaching adipose-fin supporting plate when adpressed (vs. reaching the adipose-fin plate in S. pariolispos and S. aureatus). The new species is only known from a portion of the middle Xingu River, ranging from the Volta Grande do Xingu, an area under a strong anthropic impact due to the construction of the Belo Monte dam, to near the Iriri River confluence with the Xingu River. Aspects concerning the species’ threats and its conservation status are discussed.
Keywords: Ancistrini, Brazilian shield, L082, Rapids, Rheophilic species.
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| Lateral view of live specimens of Scobinancistrus raonii, Brazil, Pará, Xingu River, Volta Grande do Xingu. Paratypes: INPA 40512, 80.9 mm SL, juvenile (above); LIA 5054, 94.4 mm SL, subadult (middle); ANSP 194989, 120.8 mm SL, adult (below). Photos: Leandro M. Sousa (juvenile and subadult) and Mark H. Sabaj (adult). |
Scobinancistrus raonii, new species
Diagnosis. Scobinancistrus raonii differs from its congeners by presenting a deeper caudal peduncle, 11.7–13.5% in SL (vs. 9.8–11.7% in S. aureatus and 9.9–11.4% in S. pariolispos); by having large yellow irregularly shaped and widely spaced spots over entire body, spots larger than pupil diameter (vs. spots smaller than pupil diameter and densely packed); by presenting last dorsal-fin ray not reaching adipose-fin plate when adpressed in specimens larger than 80 mm SL (vs. last dorsal-fin ray reaching adipose-fin plate when adpressed in young and adults); by lacking contact between hyomandibular and quadrate posteroventrally (vs. contact present). Additionally, S. raonii differs from S. aureatus by lacking a yellow large distal band on the dorsal and caudal fins (vs. present).
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| Scobinancistrus raonii hiding underneath its preferred microhabitat: conglomerate plates of gravel and iron oxide. Photo: Leandro M. Sousa. |
Etymology. The new species is named in honor of the Cacique Raoni Metuktire of the Kayapó people. Raoni is one of the most active indigenous leaders in the struggle to preserve the Amazon rainforest and indigenous peoples, being a solid reference for the fight for the conservation of the Xingu River basin for more than 40 years. A patronym.
Mateus S. Chaves, Renildo R. de Oliveira, Alany P. Gonçalves, Leandro M. Sousa and Lúcia H. Rapp Py-Daniel. 2023. A New Species of Armored Catfish of the Genus Scobinancistrus (Loricariidae: Hypostominae) from the Xingu River Basin, Brazil. Neotrop Ichthyol. 21(3):e230038. www.ni.bio.br/1982-0224-2023-0038 DOI: 10.1590/1982-0224-2023-0038
