Fin (Caudal Fin Length), A-Fin (Anal Fin Length), Pe-Fin (Average Length of Paired Pectoral Fin) and Pl-Fin (Average Length of Paired Pelvic Fin
Disc width (DW), snout length (SL), pelvic fin
length (PL), mouth width (MW), spiracle diameter (SD) and, in the case of males, the clasper length (CL) was obtained; all measurements are reported in centimeters.
dorsalis by 1) the latter's more rounded dorsoposterior corner of upper jaw (Figure 2) and 2) a pectoral fin shorter than pelvic fin
versus 1) more angular and 2) almost equal in length.
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.
Diagnosis: Dorsal rays XI,9 (1 female paratype with XI1,9); anal rays 111,9; pectoral rays 15; lateral line scales 17+7; median predorsal scales 5; horizontal rows of scales on cheek 2; gill rakers 13-15; body depth 2.85-3.40 in SL; body width 1.95-2.15 in body depth; head length 2.75-2.90 in SL; snout length 4.1-4.4 in head length; pelvic fin
short, not reaching the base of the anal fin, 4.15-4.65 in SL; caudal fin rounded to truncate in females and moderately to strongly lunate in males, caudal concavity as great as 0.8 in head; eye large, orbit diameter 3.55-3.90 in head length.
Of these, pectoral-fin length relative to the distance to the pelvic fin
is the most useful field character.
horizontal, almost in the midway between head to caudal base, origin of pelvic fins
slightly behind or just underneath dorsal fin origin; pectoral fin not reaching pelvic fin
and pelvic fin
are separated from anal; distance between pectoral and pelvic almost equal to the distance between pelvic and anal fin base; first ray of each paired fin
Roeboides guatemalensis has a large, anteriorly sometimes bifurcate, black stripe, extending between the vertical through the middle of the pelvic fin
and the vertical near the posterior terminus of the base of the dorsal fin (Lucena 2000).
A team of Australian scientists used fish living today to trace the evolution of pelvic fin
muscles to find out how the load-bearing hind limbs of the tetrapods evolved.
It is a fish but doesn't have a tail fin or a pelvic fin
, and swims vertically; it doesn't have any teeth and sucks in food through its pipe-like mouth; bones cover the exterior of its body like armor; and it is one of the only three known families of fish in which the male gets pregnant and gives birth.
The meristic counts as: dorsal fin rays XI, I, 20~22; anal fin rays II, 21~23; pectoral fin rays 16~17; pelvic fin
rays I, 5; caudal fin rays 16~17; gill rakers first arch 3~4+7~8=10~12; vertebrae 33~35 (mostly 34).
adornatus complex, by the high number of dorsal fin rays (27-28), and conse-quently a large dorsal fin base length, beginning considerably anteriorly to the middle of the body, before the vertical line through the pelvic fin
. The new species differs from the remaining species of the H.