Tuesday, January 22, 2013

[Ichthyology • 2013] Microlepidogaster arachas • a new species of hypoptopomatine catfish (Siluriformes: Loricariidae) from the upper rio Paraná basin, Brazil

Microlepidogaster arachas Martins, Calegari & Langeani 2013

Microlepidogaster arachas Martins, Calegari & Langeani, sp. nov., a new Hypoptopomatinae, is described from the upper rio Paraná basin. The new species is distinguished from M. longicolla and M. dimorpha by having the anterior portion of the compound supraneural plus first dorsal-fin proximal radial contacting the neural spine of the ninth vertebra. The new species differs from M. perforatus by having 18–29 dentary teeth; median series of lateral plates complete, reaching caudal-peduncle end, and continuous lateral line; and 20–24 mid-dorsal plates. Microlepidogaster arachas is further distinguished from its congeners by several other osteological features.

Key words: Hypoptopomatinae, Teleostei, Cascudinhos, neotropical, taxonomy, biodiversity

Etymology. The specific epithet arachas is a reference to the native people Arachás who once lived in the area drained by the rio Araguari (rio das Velhas), type-locality of the new species, and were exterminated by the Caiapós in 1750s. In the Tupi language Araxá means high place where sun can be seen first, thus Arachás were the ones that inhabited the highlands of southeastern Minas Gerais State. A noun in apposition.

Distribution. Microlepidogaster arachas is known from tributaries to rio Araguari, rio Perdizes, and rio Dourados, all pertaining to the rio Paranaíba drainage, upper rio Paraná basin.

Remarks. Microlepidogaster arachas is widely distributed at rio Paranaíba basin, its extent of occurrence is about 14.016 sq.km.  (measured by the minimum convex polygon, using GeoCat software – Geospatial Conservation Assessment Tool). The species is common and abundant (known from 15 localities), and we did not recognize any threats that may endanger it. Therefore, following IUCN criteria, we suggest that this species would fit the Least Concern (LC) category.

Martins, Fernanda O., Bárbara B. Calegari & Francisco Langeani. 2013. Microlepidogaster arachas, a new species of hypoptopomatine catfish (Siluriformes: Loricariidae) from the upper rio Paraná basin, Brazil. Zootaxa. 3608(5): 379–388.