PSEUDOPLATYSTOMA GARCIAMARQUEZI, A NEW SPECIES OF ...

Head large and deeply depressed, with dorsal profile slightly convex at the posterior part. The
lateral border of the head at the occipital region with a pronounced ridge, showing the
appearance of a quadrate head. Dorsal surface of head covered with thick skin; with the bone
exposed. Cranial fontanel short and lance-shaped, not reaching the anterior border of
supraoccipital. Eye ovoid and small with the orbital rim free, located laterally on the head.
Mouth subterminal, with the upper jaw prognathous. The teeth patch of the upper jaw visible
in ventral view. Teeth on the premaxillar small and conical, on a broad plate with the outer
posterolateral process pointed backwards. Two broad bands of small conical teeth on the
vomer.
Maxillary barbel subcylindrical, passing slightly the origin of the dorsal fin; in the holotype
the maxillary barbel almost reaches the origin of the dorsal fin. Internal mental barbels
reaching a vertical through the anterior border of the eye; outer mentals short, reaching the
border of the outer ridge of the branchiostegal membrane. Gill opening broad, free of the
isthmus. Cleithral process short and ornamented with small longitudinal ridges and knobs.
Dorsal fin with a long base located posterior to the head and connected to the cranium through
the occipital process. Posterior dorsal-fin margin straight with a spinelet and a pungent spine
and 6 branched rays (ii-6).
Pectoral spine with a large and pungent spine, with small knob in the anterior border;
numerous serrations in the posterior ridge, with 9 branched rays (i-9). Posterior pectoral-fin
margin straight and not reaching the vertical at the posterior dorsal fin base. Pelvic-fin origin
located subsequent to the vertical at the posterior dorsal fin base, with a flexible unbranched
ray and 5 branched rays (i-5). Posterior pelvic-fin margin convex, when depressed not
reaching the anal fin origin.
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