Male Morphological Description: Valves are oval in shape with deep incisur. Valve length = 1.70-1.80 mm. Valve height = 0.95-1.03 mm. Color: Light-colored valves with a yellow to lemon-yellow light organ and an orange-brown gut. Eye: brown to maroon-brown color with 16 ommatidia. Infold setae: Rostral Row (RR) with 10-16 bristles; 0-2 bristles anterior to RR. Anteroventral Row (AVR) with 13-20 bristles; 0 bristles anterior and posterior to AVR. # of tiny suckers on 1st antenna: 4-6 on proximal filament of b-bristle; 4-6 on distal filament of b-bristle; 3-6 on proximal filament of c-bristle; 3-6 on distal filament of c-bristle. 7th limb: 10-14 bristles. Furca: with 9 claws (few with 8 or 10 claws). Only claw 2 is fused.
Male Bioluminescent Display: Produce vertically downward displays 36 min after sunset. Displays start about 30-45 cm above the bottom. Displays have about 4 bright pulses followed by a rapid trill of 5-10 very dim and closely spaced pulses. Train length is 20-35 cm and lasts a maximum of 10s.
Female Morphological Description: Valves are egg-shaped with a dorsal margin that is steeply arched posteriorly. Valve length = 2.00 mm. Valve height = 1.22 mm. Infold setae: Rostral Row (RR) with 11 or 12 bristles; 0 bristles anterior to RR. Anteroventral Row (AVR) with 21 or 22 bristles; 0 bristles anterior and posterior to AVR. 7th limb: 31 bristles. Furca: with 9 claws (few with 8 or 10 claws). Only claw 2 is fused.