anal fin


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anal fin

[′ān·əl ‚fin]
(vertebrate zoology)
An unpaired fin located medially on the posterior ventral part of the fish body.
References in periodicals archive ?
On the blind side the tubercles occur at the bases of the longest dorsal and anal fin rays but are absent anteriorly and posteriorly of those areas.
Ventrum cream to light brown, dorsal and caudal fin dark blue-black, anal fin dark gray to dark blue-black, pelvic fin light with black tips, pectoral fins mostly brown-black, but distal half of unbranched rays white.
Ventral profile gently arched from lower jaw to origin of anal fin base, nearly straight on caudal peduncle.
During sidling, the male wraps his anal fin around the venter of the female in the region of her anal fin.
We are also not happy with the morphology of the mouth and anal fin.
2] treatment group, we found no phenotypic males, as discerned by the absence of any secondary sex characteristics, such as slightly yellow/bronze coloration and bright anal fin markings.
The Needham Pond population had significantly different numbers of dorsal fin spines, dorsal fin rays and anal fin rays than the populations in other regions.
Sardines (size 1/0 to 5/0 hook) and mackerel (size 3/0 to 8/0 hook) are hooked through the nose, or near the anal fin to swim deeper; since an anal-hooked bait tends to fall off the line more frequently when cast, toss the line underhand, which is not as forceful as an overhand cast.
Nearly full complements of fin spines and rays were present as early as the posttransition juvenile stage: the pelvic fin had 1 spine and 4 rays; the pectoral fin had 17 rays; the dorsal fin had 12 spines and 16 rays; and the anal fin had 2 spines and 9 rays (Table 2; Fig.
The tips of a permit tail and the anal fin (on the underside) are almost pure black, whereas those of a pompano are silvery or yellowish.