After several days, some tadpoles showed a significant reduction in tail-fin area (> 20%) and, in more extreme cases, the tail myomeres
were also damaged (16% of a random sample of 30 tadpoles).
costatus larvae had 38-43 myomeres
, whereas P argenteus had 42-43, and button of arches became evident (Fig.
In most taut-skinned fishes, the body core musculature is made up of segmented and serially arranged, cone-shaped myomeres
divided into epaxial and hypaxial muscle groups by a horizontal septum (Liem et al.
Pigmentation patterns, counts of myomeres
, head spines, and fin rays, and various measurements were recorded.
Notochord and myomeres
were easily observed 09 h 10 min AF.
were counted from the myomere
partly containing the most posterior gill opening to the last myomere
with posterior angle positioned above the cloaca (Hubbs & Trautman 1937).
Protolarvae had 22-23 post anal myomeres
and 23-24 preanal myomeres
The distribution is not symmetrical between left and right sides; they are separated by 1 to 4 myomeres
in dorsal view.
Line of pigment on ventral body margin from 4th to 6th myomeres
posterior to anus to penultimate posterior myomere
For meristic characterization, we quantified, whenever possible, the number of pre- and post-anal myomeres
, and the number of rays in the pectoral (P), pelvic (V), dorsal (D) and anal (A) fins.
They have also found that the flattened eel-like creatures had skeletal muscles called myomeres
and a basic blood vessel system.
Another characteristic of chordates are myomeres
, blocks of muscle tissue often arranged in a zig-zag pattern.