Niobichthys Schaefer, Provenzano, 1998

Delapieve, Maria Laura S., A., Pablo Lehmann & Reis, Roberto E., 2017, An appraisal of the phylogenetic relationships of Hypoptopomatini cascudinhos with description of two new genera and three new species (Siluriformes: Loricariidae), Neotropical Ichthyology 15 (4), No. e 170079, pp. 1-38 : 22-23

Genus Niobichthys Schaefer, Provenzano, 1998

Niobichthys Schaefer, Provenzano, 1998: 222 . Type-species: Niobichthys ferrarisi Schaefer, Provenzano, 1998 . Type by original designation. Gender masculine.

Included species. Niobichthys ferrarisi Schaefer, Provenzano, 1998 .

Diagnosis. Niobichthys is diagnosed based on four nonexclusive autapomorphies: serrations on inner margin of pectoral-fin spine present and oblique (char. 51.1); anterior portion of basipterygium open, bearing pair of fenestrae (char. 60.0); snout tip covered by naked area (char. 63.1); and path of preopercle-mandibular branch of laterosenory canal passes from pterotic to fifth infraorbital (char. 74.1).

Comparisons. The only species of Niobichthys is distinguished from other hypoptopomatins by the absence of a rostral plate, leaving a naked area in the snout tip (vs. rostral plate present), and by possession of conical, unicuspid accessory teeth in both the premaxilla and dentary (vs. accessory teeth absent). Niobichthys also differs from Hypoptopoma , Nannoptopoma , Otocinclus , Leptotocinclus , and Nannoxyropsis by having a strongly depressed, elongated and narrow caudal peduncle (vs. caudal peduncle not depressed). Additionally, Niobichthys is distinguished from Oxyropsis by the dorsolateral position of the eyes, which are not visible in ventral view (vs. eyes visible in ventral view), and by possession of precleithral plates (vs. precleithral plates absent). From Acestridium , Niobichthys is further distinguished by lacking the spatulate snout projection, by 14 branched rays in the caudal-fin (vs. 10 or 12 branched rays); by the lateral-line canal that shifts to the dorsal series of lateral plates after truncation of the median plate series (vs. shifting to the ventral series); and by odontodes on the dorsal surface of the pectoral-fin spine that are arranged in two or three rows (vs. odontodes randomly arranged).