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 ?
Disc wider than long, anterior margin moderately to strongly scalloped, apices of pectoral fins moderately rounded; anterior lobes of pelvic fins broad; disc shorter than tail; snout soft, flexible, especially near tip, internal supporting rostral cartilage slender and weak; teeth small, numerous, 21-28 rows in upper jaw; interorbital space flat to slightly concave; thorns absent from disc; tail thorns 19-24, interdorsal thorns 0; dorsal surface of head and body uniformly covered with small denticles, ventral surface naked; dorsal fins small, well separated, about equal in height and length.
This is called the "fluke." Remember to erase the line that made up the backbone within the dorsal fin area.
These individuals were characterized by: 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.
The measurable morphometric characters used were standard length (SL), Body weight (BWT), Total Body Length (TL), Dorsal Fin Length (DL) Caudal Fin Length (CL) Head Length (HL), Body width (BW).
Growth of bluefin tuna (Thunnus thynnus) in the North-eastern Atlantic and Mediterranean based on back-calculation of dorsal fin spine annuli.
Heterobranchus longifilis can be distinguished from all other Zimbabwean clariids by having two distinct dorsal fins: a short, rayed dorsal fin and a long adipose fin.
Richard and Russ were busy last week when they spotted a dorsal fin in the North Sea waters off Flamborough.
RW4 with 6.87% variance account to the changes of the length of the dorsal fins. The trend of shifts shows that as the dorsal fins increases its length, the length between the dorsal fin end and the caudal peduncle origin decreases.
A large nonproctractile mouth with protruding lower jaw, strong teeth in jaws and exposed maxilla, two continuous dorsal fin, with the base of spinous dorsal fin longer than that of soft-rayed fin (excluding finlets).
The new species is distinguished from other Austrolebias species by the unique male pigmentation pattern of the dorsal fin, with black vertical bars elongated from the base to the medial portion of the fin, and by the pattern of transversal black bars on the body, which become gradually shorter and fainter towards caudal peduncle.
All humpback dolphins have a characteristic hump just below the dorsal fin, but there are several distinct species in this family of marine mammals, the scientists found.