Distomedian petasma projection with fully developed or vestigeal apical filament

Thelycum of impregnated female usually with white conjoined pads

Rostrum wide and short, not reaching to distal end of basal antennular segment

Thelycum with ovoid anterior and lateral plates of subequal size

Apical filaments of petasma vestigial, represented by a pair of rounded bosses

Rostrum projecting beyond basal antennular segments, with a marked edentate distal portion

Posterior part of rostrum with distinctly elevated crest

Each distomedian projection of petasma with a long and slender spical filament

Thelycum with a large anterior plate, lateral plates boomerang shaped and enclosing two pear shaped plates

Posterior part of rostrum without distinctly elevated crest and double curve, adrostral crest reaching as far as epigastric tooth

In adult males, basial spine of third pereopod exttremely long and barbed

Thelycum with a long, agrooved tongue like anterior plate

Distomedian petasmal projection flap like

Ischial spine on 1st pereopod distinct, rostrum straight

Distomedian projection of petasma convoluted, greatly swollen, bulbiform directed anterolaterally and concealing distolateral projections in ventral view

The anterior plate of thelycum long and deeply grooved

Lateral plate with strongly raised lateral margins forming 2 longitudinal crests

Ischial spine on 1st pereopod small or absent, rostrum slightly curved upward

Distomedian projections of petasma crescent shaped

The anterior plate of thelycum deeply grooved longitudinally and considerably wider posteriorly