Saturday, June 9, 2012

[Ichthyology • 2011] Fonchiiloricaria nanodon • Intergeneric phylogenetic relationships in catfishes of the Loricariinae (Siluriformes: Loricariidae), with a new genus Fonchiiloricaria from Peru

Fonchiiloricaria nanodon Rodriguez, Ortega & Covain 2011

Recent investigations in the upper Río Huallaga in Peru revealed the presence of an intriguing species of the Loricariinae. To characterize and place this species within the evolutionary tree of the subfamily, a molecular phylogeny of this group was inferred based on the 12S and 16S mitochondrial genes and the nuclear gene F-reticulon4. The phylogeny indicated that this distinctive species was a member of the subtribe Loricariina. Given its phylogenetic placement, and its unusual morphology, this species is described as a new genus and new species of Loricariinae: Fonchiiloricaria nanodon. This new taxon is diagnosed by usually possessing one to three premaxillary teeth that are greatly reduced; lips with globular papillae on the surface; the distal margin of lower lip bearing short, triangular filaments; the premaxilla greatly reduced; the abdomen completely covered by plates, with the plates between lateral abdominal plates small and rhombic; a caudal fin with 14 rays; the orbital notch absent; five lateral series of plates; dorsal-fin spinelet absent; preanal plate present, large and solid, and of irregular, polygonal shape, the caudal peduncle becoming more compressed posteriorly for the last seven to 10 plates.

Keywords: neotropics; molecular phylogeny; morphology; systematics

Figure 7. Holotype of Fonchiiloricaria nanodon, MUSM 37953, 160·8 mm standard length,

Figure 8. Sexual dimorphism in Fonchiiloricaria nanodon (dorsal view). (a) Female and (b) male

Rodriguez, M. S. , H. Ortega, and R. Covain 2011. Intergeneric phylogenetic relationships in catfishes of the Loricariinae (Siluriformes: Loricariidae), with the description of Fonchiiloricaria nanodon: a new genus and species from Peru. Journal of Fish Biology. 79 (4): 875-895.