Main Ref. | Ibala Zamba, A., G. De Boeck, V. Mamonekene and E. Vreven, 2007 |
Appearance refers to | |
Bones in OsteoBase |
Specialized organs | |
Different appearance | always different morphology between mature adults |
Different colors | |
Remarks | There is a well-marked sexual dimorphism in the dorsal and anal fins: in males, all dorsal-fin rays, except the first and the last two, are filamentously elongated and can attain up to 70.7% of the standard length; the distal border of the anal fin is straight in females, juveniles and immature specimens, but slightly convex anteriorly in males (Ref. 74421). |
Striking features | |
Body shape lateral | fusiform / normal |
Cross section | |
Dorsal head profile | |
Type of eyes | more or less normal |
Type of mouth/snout | more or less normal |
Position of mouth | terminal |
Type of scales | |
Diagnosis |
Bryconaethiops yseuxi can be distinguished from all other known Bryconaethiops species based on the following unique combination of characters: a high number of scale rows between anterior origin of dorsal fin and lateral line (7.5 vs. 6.5 or less); a low number of gill rakers on the first gill arch; and a long dorsal-fin and anal-fin bases, respectively 15.7-17.6% and 22.7-25.9% of standard length (Ref. 74421). Body deep and somewhat laterally compressed (Ref. 74421). Mouth terminal; upper jaw with three rows of premaxillary teeth; external row composed of two small median teeth with a small lateral cusp at their outer side; a median row with 6 or 7 teeth; and an inner row of 8 pluricuspid teeth with their cusp on a median row and without an anterior cusp or row of cusps as generally found in the other Bryconaethiops species (Ref. 74421). Lower jaw with an external series of 6 large pluricuspid teeth and an inner row of two median caniniform teeth (Ref. 74421). Lateral line scales 34-39; longitudinal line scales 36-40 (Ref. 74421). Head and body of live mature male specimens silvery with a pinkish hue on sides of the body; upper side of head green-olive; humeral spot present but not well marked; adipose-fin whitish transparent, blackish at base (Ref. 74421). After preservation, body yellowish white; darker above lateral line with scales above lateral line faintly dark brown on their basal part; fins whitish, transparent in overall appearance; humeral spot not well distinguishable, or even regularly absent (Ref. 74421). |
Ease of Identification |
Lateral Lines | Interrupted: No |
Scales on lateral line | 34 - 39 |
Pored lateral line scales | |
Scales in lateral series | |
Scale rows above lateral line | 7 - 7 |
Scale rows below lateral line | 3.5 - 4.5 |
Scales around caudal peduncle | 12 - 12 |
Barbels | |
Gill clefts (sharks/rays only) | |
Gill rakers | |
on lower limb | 11 - 13 |
on upper limb | 8 - 12 |
total | 20 - 25 |
Vertebrae | |
preanal | |
total |
Attributes | no striking attributes |
Fins number | 1 |
Finlets No. | Dorsal 0 - 0 |
Ventral 0 - 0 | |
Spines total | 0 - 0 |
Soft-rays total | 10 - 10 |
Adipose fin | present |
Attributes | forked; more or less normal |
Fins number | 1 |
Spines total | 0 - 0 |
Soft-rays total | 21 - 23 |
Pectoral | Attributes more or less normal |
Spines | |
Soft-rays | |
Pelvics | Attributes more or less normal |
Position abdominal behind origin of D1 | |
Spines | |
Soft-rays |