| Main Ref. | Anderson, W.D. Jr., 2008 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral | |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | |
| Diagnosis |
This species is distinguished from its congeners (except P. exsul and P. parini) by the following set of characters: 28-31 total gillrakers on first gill arch (vs. 13-25, usually fewer than 20); 17-18 circum-caudal-peduncular scales (vs. 20-22 in P. exsul); 36-42 tubed lateral-line scale (vs. 40-46 in P. exsul); some body proportions and coloration (P. nazcae with red oblong area below posterior end of soft dorsal fin, extending onto caudal peduncle vs. P. parini with 2 orange-red bars on posterior half of body) (Ref. 83536). |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | |
| Scales in lateral series | |
| Scale rows above lateral line | 1.5 - 2 |
| Scale rows below lateral line | 3 - 4 |
| Scales around caudal peduncle | 17 - 18 |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | 19 - 22 |
| on upper limb | 7 - 10 |
| total | 28 - 31 |
| Vertebrae | |
| preanal | |
| total |
| Attributes | |
| Fins number | |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | 10 - 10 |
| Soft-rays total | 16 - 16 |
| Adipose fin |
| Attributes |
| Fins number | |
| Spines total | 3 - 3 |
| Soft-rays total | 7 - 7 |
| Pectoral | Attributes |
| Spines | |
| Soft-rays 16 - 17 | |
| Pelvics | Attributes |
| Position | |
| Spines 1 | |
| Soft-rays 5 - 5 |