A new Hoplisoma species (Siluriformes: Callichthyidae) from the Rio Madeira basin, Brazilian Amazon
DOI:
https://doi.org/10.11606/1807-0205/2026.66.013Keywords:
Biodiversity, Corydoradinae, Rio Manicoré, Rio Marmelos, TaxonomyAbstract
Scientific expeditions to the Madeira-Tapajós interfluvial region resulted in the capture of a peculiar small species of Hoplisoma, which is confirmed as new and described herein. The new species can be promptly diagnosed from its congeners by the following features: (I) four to five brownish to black blotches on flank midline, similarly-sized or slightly larger than others on flank; (II) dark-brown to black band on medio-distal portion of dorsal fin; (III) absence of conspicuous dark spots on regions of head and trunk; (IV) ventral laminar expansion of infraorbital 1 poorly-developed, reaching transversal line through dorsal portion of preopercle, and (V) posterior portion of supraoccipital contacting nuchal plate. Notably, the new species represents the first described Corydoradinae species from two Rio Madeira drainages: Rio Manicoré and Rio Marmelos. A discussion on the biogeography of the new species, as well as the imminent ecological threat faced by it, is provided.
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Fundação de Amparo à Pesquisa do Estado de São Paulo
Grant numbers 2024/03613-8;2013/22473-8 -
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Grant numbers 88887.910517/2023-00;88887.084586/2024-00
