This species is distinguished from its congeners by the following characters: lower lip with a distinct narrow area completely lacking of papillae along and just posterior to each emergent tooth series of the dentary (vs. area posterior to tooth series of the dentary covered by papillae) and by having a short maxillary barbel, mostly adnate to lower lip by distinctly enlarged skin flap forming a continuous connection from the base to almost the end of the maxillary barbel (vs. small flap of skin connecting the maxillary barbel); further distinguished by the papillae in upper lip coalesced to form 3 or 4 transverse series of elongate skin folds anterior to the premaxillary tooth series (vs. papillae rounded, not fused to form skin folds); differs from all its congeners, except P. garapia, P. garbei, P. nasuta, P. proskynita, P. splendens, P. vestigipinnis, P. vetula by having a smaller eye diameter 8.5-11.3% (vs. 11.7-18.8% HL) and it differs from these seven species by having the soft fleshy lobe on the lateral margin of head progressively wider posteriorly in adult males (vs. soft fleshy lobe not widening posteriorly along the lateral margin of the head); differs from P. garapia, P. vestigipinnis, P. vetula by having a well-developed dorsal-fin spinelet (vs. dorsal-fin spinelet absent); differs from P. garbei by having bifid teeth, with a small lateral cusp in both the dentary and the premaxilla (vs. teeth simple, without lateral cusp in both dentary and premaxilla); differs from P. proskynita, P. vestigipinnis in having an adipose fin (vs. adipose fin absent); differs from P. splendens by the long first unbranched pelvic-fin ray, approximately equal in size or longer than the pectoral-fin spine (vs. first unbranched pelvic-fin ray short, always shorter than the pectoral-fin spine); differs from P. nasuta by having the lateral tooth cusp longer, almost reaching or reaching to middle of medial cusp (vs. lateral cusp minute, never reaching to middle of medial cusp) (Ref. 119415).