| Main Ref. | Carvalho, T.P., A.T. Thomaz, A. Urbano-Bonilla and S. Prada-Pedreros, 2024 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks | Adult males with enlarged urogenital papilla (none in females), its length about one-third to half of the first unbranched anal-fin ray, in contact with the first anal-fin unbranched ray; urogenital papilla covered by the sheath of enlarged scales on the anal fin; with highly modified anal fin with enlarged (anteroposteriorly) and distally elongated first and second anal-fin branched rays, forming a gonopodium like structure; have first branched rays distally expanded; no hooks were observed on the fins of mature males. Females with no highly enlarged anal-fin, rays have a concave posterior border (Ref. 132484). |
| Striking features | |
| Body shape lateral (shape guide) | |
| Cross section | compressed |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | |
| Diagnosis |
The species is distinguished from all Stevardiinae species by the following set of characters: adult males with enlarged urogenital papilla (length about one-third to half of the first unbranched ray), which is in contact with the first anal-fin unbranched ray and a highly modified anal fin, with enlarged (anteroposteriorly) and distally elongated first and second branched anal-fin rays, forming a gonopodium-like structure; differs from its congenerspresence of an adipose fin (vs. absent); lateral line incomplete, pored scales not reaching the caudal fin (vs. lateral line complete); ascending process of the premaxilla dorsally directed (vs. strongly bent posteroventrally); snout longe, about a fourth of the head length (HL), between 23.1%- 30.0% of HL (vs. short snout, <20% of the HL) (Ref. 132484). |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | 28 - 34 |
| 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 | 7 - 11 |
| on upper limb | 5 - 7 |
| total | |
| Vertebrae | |
| preanal | 14 - 16 |
| total | 36 - 37 |
| Attributes | |
| Fins number | |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | |
| Soft-rays total | 7 - 7 |
| Adipose fin |
| Attributes |
| Fins number | |
| Spines total | |
| Soft-rays total | 11 - 13 |
| Pectoral | Attributes |
| Spines | |
| Soft-rays 9 - 11 | |
| Pelvics | Attributes |
| Position | |
| Spines | |
| Soft-rays 6 - 6 |