- closed petasma
- The lateral lobes are heavily sclerotized, sometimes making structure virtually rigid, with the ventral costae situated ventromesially, almost abutting, and delimiting a small, sometimes extremelyso, space; lateral lobe usually produced distally into lateral sprouts or horns. See: petasma [Perez Farfante and Kensley, 1997].
Crustacea glossary. Natural History Museum of Los Angeles County. 2011.