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 ?
The presence of more than three anal fin spines is also characteristic of the Cichlidae and excludes identification as a labroid (Carpenter, 2001).
The testes and anal fin were dissected and preserved in Bouin's fixative and 10% neutral-buffered formalin, respectively, then transferred to 70% ethanol.
Counts included: dorsal fin spines and rays, anal fin spines and rays, pectoral fin rays, pelvic fin spines and rays, caudal fin rays, gill rakers on the first gill arch, vertebrae, scales in lateral line, scales above lateral line, and scales below lateral line.
The specimen had very dark mottled coloration, an anus closer to the edge of the suctorial disk than the origin of the anal fin and a single row of teeth in the lower mandible.
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.
3] is variable in females, merging into a dark stripe from the level of the caudal end of the anal fin to the caudal end of the head.
Dark lateral stripe continuous with caudal-peduncle spot; caudal-peduncle spot rounded, and not extending onto middle caudal-fin rays; 15-17 pored lateral-line scales; six scales between lateral line and anal-fin origin; six scales between lateral line and pelvic-fin insertions; nine predorsal scales; ii,8,i dorsal-fin rays; anal fin with 21-22 branched; pectoral-fins with twelve branched rays; males with bony hooks on anal and pelvic fins H.
Cut completely through the fish along the lateral line from behind the gills past the anal fin.
rei-t-hertz), lower anal fin base length and caudal fin length in males, and the lower head depth (except in A.
Sex was identified visually using the elongated anal fin length in males (Winn, 1958; Williams, 1075; Simon and Wallus, 2006; Fig.