Petasma without pars astringens

Procurved tooth present between bases of first pair of pleopods

Lower antennular flagella with one clasping spine

Anterior margin of genital coxae pointed

Petasma with pars astringens

Procurved tooth between bases of first pair of pleopods

Procurved tooth absent

Lower antennular flagella with 2 clasping spines

First segment of main branch of lower antennular flagella without traingular projection