Pareiorhina rudolphi, photo by K.S. Cummings
P. brachyrhyncha Chamon, Aranda, and Buckup 2005
P. carrancas Bockman and Ribeiro 2003
P. microps (Ihering 1907), name replaced by P. rudolphi
P. rudolphi Miranda Ribeiro 1911
|1a.||Postdorsal surface of trunk with a low ridge formed by 10-13 azygous plates extending between dorsal and caudal fin; lower lip with a smooth, unpapillose band just external to the toothed portions of dentaries||
|1b.||Postdorsal sur face of trunk without median ridge; lower lip entirely papillose||
|2a.||Teeth with minute lateral cusp; cleithral width more than 31% of standard length in specimens above 25 mm SL; tip of snout covered with plates.||
|2b.||Teeth unicuspid; cleithral width less than 31% of standard length in specimens above 25 mm SL; tip of snout without plates.||
Pareiorhina is a small loricariid that lacks an adipose fin.
Color is dark brown with a slight mottling or five dorsal saddles, the
first at the origin of the dorsal fin, the second just posterior to the
dorsal fin, the third on the middle of the caudal peduncle, the fourth
at the posterior end of the caudal peduncle, and the fifth on the caudal
fin near its base. Abdomen mostly white with a few small, scattered
melanophores posteriorly and near the gills, the caudal peduncle is brown
but lighter than the sides, and the fins are spotted or clear. Abdomen
naked, but parts of the coracoid strut may be exposed and support odontodes.
Pterotic-supracleithrum bordered posteriorly by a section with many small
plates (as in some Rhinelepini). Caudal fin slightly emarginate.
Four or more predorsal plates. Three rows of plates on the caudal
peduncle. Postdorsal plates in the dorsal row form a keel dorsolaterally
so that there appears to be a furrow between the dorsal and caudal fins.
Dorsal fin is short.
Pareiorhina differs from Hemipsilichthys, Delturus, and all Neoplecostominae by the lack of an adipose fin and a partially exposed coracoid ventrally. Appears similar to some Pogonopomoides and Rhinelepis (particularly
juveniles), sharing the numerous small plates behind the head, loss of
the adipose fin, and an exposed coracoid. Differs from Rhinelepis
by having small (vs. very large) gill openings and a large, ventrally deflected
canal plate (vs. two small canal plates). Differs from Pogonopomoides
by having a small, square dorsal fin spinelet (vs. large and triangular)
and only three (vs. 5) rows of plates on the caudal peduncle. Pareiorhina
differs from Hypoptopomatinae by lacking large plates on the abdomen and/or
complete or nearly complete exposure of the pectoral girdle, from Hypostominae
by having a small, rectangular dorsal fin spinelet (vs. large and triangular)
- and from hypostomines with an unexposed spinelet by the lack of evertible
cheek odontodes, and from Loricariinae by having an oval (vs. rectangular
and compressed) cross-section of the caudal peduncle.