A new tiny-spotted species of Hypostomus (Siluriformes: Loricariidae) from the upper Rio Tocantins basin, Gois State, Brazil.

Scientific visits to ichthyological collections revealed a potentially new species of Hypostomus from the Rio Tocantins basin. From there, subsequent ichthyological surveys led us to capture the taxon in the upper portion of this basin and address it to the H. punctatus group. Here, we present it as a new species to science. The new species is distinguished from its congeners, except those from the H. punctatus group, by having bicuspid teeth with elliptic medial cusps, moderate keels on the head and flanks, small spots on the body, and caudal peduncle that are long and low. From the H. punctatus group, except H. subcarinatus and H. commersoni, it differs by having extremely small dark spots; from H. subcarinatus, it differs by having a beige-brown dorsal-fin background color versus blue in live specimens; and from H. commersoni, it differs by having a short to moderate dorsal fin versus a long dorsal fin.

Assessing two hundred years of taxonomic doubt with the rediscovery and taxonomic establishment of the Amazonian armored catfish Hypostomus pantherinus Kner 1854 (Siluriformes: Loricariidae).

Hypostomus pantherinus was described by Kner in 1854 based on a single young specimen collected by Natterer with a type-locality just asserted as Guapor. No robust scientific paper focusing the distribution, taxonomy and ecology of this species has been published since the description. Here, based on the analysis of the holotype, recently collected material, and on an extensive searching on ichthyological fish collections, H. pantherinus Kner 1854 is redescribed and its geographical distribution is established to be in the rio Itez-Guapor and the mouth of its Bolivian and Brazilian tributaries. Hypostomus pantherinus is distinguished from congeners mainly by villiform teeth, conspicuous black, sharp and widely spaced spots on head, and dark blotches on trunk and fins, keels along lateral series of plates, sharp crests on supraoccipital and on compound pterotic-supracleithrum, less than 25 spots on compound pterotic-supracleithrum, one blotch per interradial membrane along each row on dorsal fin, and by usually attaining about 160 mm SL in size.