Species: Poecilia vivipara, Southern molly

Poecilia vivipara Bloch & Schneider, 1801

Southern molly

Head and body moderately robust, moderately compressed at rear; head depressed; front nostril not tubular; covering of eye not continuous with skin of head; mouth small, at front, slightly oblique, lower jaw slightly projecting, top jaw protractile; jaw teeth consist of an outer row of large backward curved teeth with expanded tips, and several rows of small pointed teeth, with 1-3 points; 1 dorsal fin with short base, its origin behind pelvic origin, 7-9 rays, elongate in male; pelvic origin well behind pectoral base, near anal fin; tip of pelvic fin of males swollen, elongate; pectorals high on flank, 5th ray not scalloped in male; anal fin 8-10, origin at or a little before (female) to a little before (male) dorsal fin origin; 3rd anal ray unbranched; anal fin modified in male to form an elongate sex organ, that organ relatively short, with straight tip that has small spines & a  fleshy palp; tail base relatively narrow; tail fin rounded, without elongate sword; scales smooth and relatively large; 24-27 lateral scale rows; scales around tail base 16.