| Main Ref. | Ebert, D.A., J. Alfaro-Shigueto, X. Velez-Zuazo, M. Pajuelo and J.C. Mangel, 2022 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral (shape guide) | |
| Cross section | flattened |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | |
| Diagnosis |
This large species (to at least 112.6 cm TL) with a rhombic disc, is distinguished from other Peruvian species (as well as all other southeast Pacific congeners) by the following characters: a uniform black-to-chocolate or dark-plumbrown colouration, notably the same on both dorsal and ventral surfaces (vs. dorsal and ventral surfaces of different colors, except B. aguja; an irregular spotted pattern on both dorsal and ventral surfaces (vs. no spotting or, in B. aguja, two symmetrically arranged, large, white spots on dorsal surface at pectoral-fin bases and symmetrically arranged white spots along disc margins); differs from Peruvian congeners by having more precaudal vertebrae 79-81 (vs. 62-71); fewer pectoral-fin radials 69-70 (vs. 72-83) (Ref. 127873). |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | |
| Scales in lateral series | |
| Scale rows above lateral line | |
| Scale rows below lateral line | |
| Scales around caudal peduncle | |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | |
| Vertebrae | |
| preanal | |
| total |
| Attributes | |
| Fins number | |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | |
| Soft-rays total | |
| Adipose fin |
| Attributes |
| Fins number | |
| Spines total | |
| Soft-rays total |
| Pectoral | Attributes |
| Spines | |
| Soft-rays | |
| Pelvics | Attributes |
| Position | |
| Spines | |
| Soft-rays |