Mating in Myodocopina (Crustacea: Ostracoda): Results from Video Recordings of a Highly Iridescent Cypridinid

Extract

The first account of mating in a myodocopine using evidence from video recordings is presented herein for Skogsbergia sp. (Cypridinidae). After initial courtship the male and female ostracods, with ventral margins adjacent and anterior ends directly opposite, join their mandibular claws and furcae. Both furcae are pushed in a posterior direction until the ventral margins of the carapace meet. In this position, with genitalia directly opposite, copulation presumably occurs. This mating procedure lasts for five seconds.

Myodocopine ostracods are diverse marine crustaceans occurring world-wide at depths from 0–6000 m (Kornicker, 1975). All myodocopines reproduce sexually (Cohen & Morin, 1990). Some bioluminescent cypridinids (Myodocopina) use luminescent signalling during courtship; males produce species-specific patterns of flashes in the water column to attract females (Morin, 1986). Although myodocopines may be amongst the most abundant macroinvertebrates on the continental shelf (J.K. Lowry, personal communication), they have been the subject of relatively few behavioural studies, and in particular their copulation process is poorly documented (Cohen & Morin, 1990).

Two accounts of myodocopine mating have been reported. In 1914 the cypridinid Vargula hilgendorfii (Muller, 1890) was observed mating in a Petri dish (Okada & Kato, 1949). The male clasped the female using the first antennae while swimming with the natatory second antennae. After 30 to 60 min they rested on their lateral sides, with ventral margins touching and heads facing in opposite directions; the penis (lying between the paired copulatory ‘limbs') was protruded into the female carapace and the spermatophore was transferred. This copulation lasted more than 30 min (Okada & Kato, 1949).