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| Rineloricaria buckupi Mejia, Ferraro & Souto-Santos, 2025 |
Abstract
A new species of Rineloricaria from the São João and Macaé river basins in Rio de Janeiro State, southeastern Brazil is described. The new species is distinguished from most of its congeners by possessing of five series of lateral plates below the dorsal fin; mid-dorsal series consisting of four or five keeled plates extending posteriorly beyond the origin of the dorsal fin; pectoral girdle covered by plates; snout tip with naked area not reaching most anterior pore of infraorbital ramus of sensory canal; dorsal-fin spinelet present. The new species differs from R. zawadzkii, the most similar and geographically closest species, by having mid-ventral and lateral abdominal plates in contact (vs. separated by skin), the dorsal fin with a dark brown terminal band not reaching the edge, with inconspicuous dark dots along the lower edge (vs. band reaching the edge), and the caudal fin with a diffuse distal band with variegated white spots (vs. a well-defined distal band). The genetic distance based on cytochrome c oxidase I between the new species and the closest congeners supports its validity. The current distribution of the new species in the São João and Macaé basins is consistent with paleo-drainage connections influenced by sea-level fluctuations.
Keywords: DNA barcode; Freshwater fishes; Loricariinae; Sea-level variations; Suckermouth armored catfishes
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| Rineloricaria buckupi, holotype, MNRJ 51116, 111.2 mm SL, Brazil, Macaé, Macaé River; lateral, dorsal, and ventral views. |
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| Rineloricaria buckupi, paratypes. Note the remarkable dark brown transverse bars on dorsal surface. A. MNRJ 54658, 77.9 mm SL; five bars on dorsal surface. B. MNRJ 54658, 101.8 mm SL; notice third and fourth bars fused. |
Rineloricaria buckupi, new species
Diagnosis. Rineloricaria buckupi can be distinguished from most congeners except for R. aequalicuspis Reis & Cardoso, 2001, R. altipinnis, R. anhaguapitan Ghazzi, 2008, R. anitae Ghazzi, 2008, R. baliola Rodriguez & Reis, 2008, R. cacerensis (Miranda Ribeiro, 1912), R. cachivera, ..., R. zaina Ghazzi, 2008 and R. zawadzkii by having five lateral series of plates below the dorsal fin (vs. four lateral series of plates below the dorsal fin), and mid-dorsal series extending below and posterior to dorsal fin (vs. mid-dorsal series not extending beyond the origin of dorsal fin). Rineloricaria buckupi differs from R. aequalicuspis, R. anhaguapitan, R. baliola, R. capitonia, R. latirostris, R. maacki, R. malabarbai, R. maquinensis, R. microlepidogaster, R. nudipectoris, R. reisi, and R. tropeira by the extensive ventral covering of the pectoral girdle by plates (vs. absence of plates on most of the ventral surface of the pectoral girdle). It differs from R. cacerensis, R. fallax, ...
Etymology. The specific name buckupi (noun, masculine, singular genitive), is a patronym for Paulo A. Buckup, in recognition of his valuable teachings as an advisor to numerous students, including the authors of this paper. Paulo has done outstanding work and made numerous contributions to Neotropical ichthyology, including advances in the systematics of Rineloricaria over the past 25 years.
Mejia, Eduardo; Ferraro, Gustavo A. and Souto-Santos, Igor C. A. 2025. A New Species of Whiptail Catfish Rineloricaria (Siluriformes: Loricariidae) from Macaé and São João River Basins, southeastern Brazil. Neotrop. ichthyol. 23 (02); DOI: doi.org/10.1590/1982-0224-2024-0087
