dorsal fin


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Related to dorsal fin: caudal fin

dorsal fin

n.
One of one or more unpaired fins on the back of fishes and certain marine mammals.

dorsal fin

any unpaired median fin on the backs of fishes and some other aquatic vertebrates. The fin maintains balance during locomotion.
References in periodicals archive ?
Colour of holotype in alcohol pale brownish yellow, with a faint, dusky-edged, pale stripe, narrower than pupil, beginning above opercle and extending parallel to dorsal profile of postorbital head and nape to below rear half of first dorsal fin; dorsal fins with pale yellowish rays and faintly dusky membranes; remaining fins pale yellowish.
This group is easily identifiable due to the long dorsal fin, which begin before the pelvic fin in males and the presence of two small black spots in the caudal peduncle of females.
It lives in shallow waters from Morocco to the English Channel and spends most of its time buried under the sea bed with only its eyes and venomous dorsal fin poking out from the sand.
Caudal-fin base dark yellow, lobes hyaline; pectoral fin yellow with rays dark basally, pelvic fins hyaline, dorsal fin with dark bands extending on to rays, more pronounced on the tips.
Body depth is the greatest depth to the base of the dorsal fin (adjusting for any malformation of the abdomen due to preservation).
6 % of SL, calculated from photographs), taller first dorsal fin, and longer soft dorsal and anal rays.
Based on examination of these genetically identified individuals, significant differences were found in body color, specifically spotting on the spinous dorsal fin or an overall darker color (or both) in S.
The diacritically meristic counts were listed as follows: first dorsal fin with a single small isolated spine anteriorly; gill rakers 2-3+4-6=6-9; pored lateral line scales 73-80 and caudal fin with a yellow marking on the middle when fresh.
This particular species of dolphin has a highly variable dorsal fin shape which can sometimes be so tall and straight that they are mistaken for their larger relatives, the killer whale.
smooth dogfish and Florida/Gulf smoothhound) Predorsal ridge present; second dorsal fin slightly smaller than first dorsal fin and much larger than anal fin; max.
Anterior dorsal fin has spines which are not separated from posterior one that has one spine and 13 fins rays [3].