hypural


Also found in: Dictionary.

hypural

[hī′pyu̇r·əl]
(vertebrate zoology)
Of or pertaining to the bony structure formed by fusion of the hemal spines of the last few vertebrae in most teleost fishes.
Mentioned in ?
References in periodicals archive ?
ensifer, and it has melanophores on the snout and upper jaw, on the isthmus, and on the hypural margin, which are all lacking in S.
During this stage, a row of 4 neuromasts along the margin of hypural plates is noticeable (Fig.
Inferior hypural is probably the result of fusion of the first two hypurals (H1 and H2).
For example, when using standard length, determination of where the caudal peduncle ends greatly depends on the individual reader and where they feel the hypural bone ends.
Large patch of pigment present on caudal peduncle with band extending posteriorly to cover hypural area.
1998): body length (BL), distance from the tip of the snout to the notochord tip (in preflexion and flexion larvae), and to the posterior margin of the hypural bones (postflexion larvae and posttransition juvenile); eye diameter (ED), longest diameter of the eye; snout length (SnL), distance from the tip of the snout to the anterior margin of the eye; head length, distance from the tip of the snout to the posterior margin of the opercle; body depth, vertical distance on pectoral fin base; preanal length, distance from the tip of the snout to the anus.
Lengths of specimens are given as standard length (SL) except estimates of total length (TL) of fishes photographed underwater; this is the straight-line measurement from the front of the upper lip to the base of the caudal fin (end of hypural plate).
Dorsal fin X or XI, 16 or 17; anal fin III, 16; pectoral fin 19 or 20; Caudal fin: procurrent rays 4 + 4-5, segmented rays 8 + 8, middle 12 branched, total elements 24 of 25; fifth hypural present or absent Vertebrae: 10 + 19; last pleural rib on vertebra 10; epineural ribs 12; one supraneural bone.
The first caudal vertebra was defined as the first centrum with a long haemal spine, and the centrum fused to the hypural plate was counted as the last vertebra.
For each date, we calculated a size distribution, with 4 mm size classes, based on the standard length, SL (tip of snout to hypural zone), of the fish.