Rhinelepis parahybae Steindachner 1877:2-5, p,. 2, dem Parahyba.
Pogonopomoides is diagnosed by: a wide ventrolateral strut of
the coracoid (28-1); passage of the arrector ventralis muscle of the pectoral
girdle through a channel (30-1); very elongate and pointed posterior processes
of the pelvic basipterygium (33-2); and loss of the initial anterior section
of the diverticulum (40-4).
Pogonopomoides appears intermediate in shape between
and Pogonopoma. Pogonopomoides is fairly dorsoventrally
flattened with long pectoral and pelvic fins compared to others in the
group. The body is charcoal gray and without spots in alcohol preserved
specimens. The abdomen is naked except for a row of plates laterally
(they are not as large as those in Pogonopoma) and a few randomly
placed small plates along the pectoral girdle as well as elsewhere.
Gill openings are large, but not as large as in Rhinelepis. The cheek
lacks elongate odontodes. Dorsal II-7, pectoral I-6, pelvic I-5,
anal 6 (1 unbranched, 5 branched), caudal I-14-I. 24-26 lateral line
plates, 7 plates under the base of the dorsal fin, 11-13 plates in the
depressed dorsal fin, 12-15 postdorsal plates, 11-13 postanal plates, and
73-98 teeth per jaw ramus.
Pogonopomoides can be identified from most other loricariids
by a combination of a loss of the adipose fin and median pre-adipose plate,
a well developed dorsal fin spinelet (vs. a small, rectangular spinelet
or no spinelet in Hemipsilichthys, Isbrueckerichthys, Kronichthys,
and Corymbophanes andersoni), six anal fin rays, and a coracoid
that is exposed ventrally. Within the Rhinelepis group,
differs from Pogonopoma by the lack of elongate cheek odontodes
and lack of an adipose fin; from Pseudorinelepis by the lack of
tall ridges on the pterotic-supracleithrum, lack of cheek spines, an
plated abdomen, and the following morphometric features (Table 2): a longer
snout length/SL ratio (0.176-0.193 vs. 0.138-0.176), a shorter thorax length/SL
ratio (0.189-0.233 vs. 0.258-0.317), a smaller head depth/SL ratio (0.155-0.190
vs. 0.200-0.260), and a smaller cleithral width/SL ratio (0.233-0.275 vs.
0.275-0.311); and from Rhinelepis by having smaller gill openings,
only a few plates on the abdomen (versus fully plated), an exposed
projection of the coracoid, lack of a plate between the opercle and the
pterotic-supracleithrum, and the following morphometric features (Table
2): a smaller predorsal length/SL ratio (0.373-0.400 vs. 0.430-0.473),
a smaller head length/SL ratio (0.304-0.326 vs. 0.347-0.396), a smaller
snout length/SL ratio (0.176-0.193 vs. 0.210-0.243), a smaller interorbital
width/SL ratio (0.120-0.137 vs. 0.182-0.194), a larger postanal length/SL
ratio (0.260-0.289 vs. 0.203-0.241), a larger dorsal fin length/SL ratio
(0.235-0.256 vs. 0.195-0.212), a smaller head depth/SL ratio (0.155-0.190
vs. 0.214-0.243), and a smaller cleithral width/SL ratio (0.233-0.275 vs.
There is one species, Pogonopomoides parahybae, in the Rio Paraíba of southeast Brazil (see below).
The question mark refers to a potentially introduced population of Rhinelepis.
Armbruster, J.W. 1998. Phylogenetic relationships of the suckermouth armored catfishes of the Rhinelepis group (Loricariidae: Hypostominae). Copeia 1998:620-636.