Reproductive biology of the nudibranch Doris jontainei d'Orbigny, 1835 (Gastropoda: Opisthobranchia) from the Magellanic Region

MUNIAN, CLAUDIA; GALLARDO, C. S.; PABLO E. PENCHASZADEH

THE NAUTILUS (PHILADELPHIA)

BAILEY-MATTHEWS SHELL MUSEUM

Lugar: Philadelphia; Año: 2007 vol. 121 p. 139 - 145

0028-1344

The present study describes the egg deposítíon, embryonic andlarval development, and reproductive behavioral traits of theSouth American doríd nudibranch Doris [ontainei d´Orbigny,1835, observed in laboratory under controlled conditions. Behaviorduring copulation and spawning was recorded using adigital video camera. Copulation and spawning lasted 2-4 h and22-23 h, respectively. The spawned mass reached 1.80 m inlength and was coiled in a counter-c1ockwise direction from thecentre with one edge affixed to the substrate. The ribbon containednumerous small capsules, each having 2-4 eggs of about86 urn in diameter. Intracapsular egg development lastedabout 14 days at 14.5°C, culminating with the release of up to1.25 million veliger larvae per egg mass. The new veliger larvaeshowed incipient development of the foot and a relatively smallprotoconch (ea. 158 u.m), indicating they enter a planktotrophicphase. A comparison with other nudíbranchs, and partícularlywith doríds, suggests that D. jontainei has an annual cyclewhose egg mass fits a morphological pattern typical of the family.The characteristics of its encapsulated development show itis one of the most fecund species among those having thíspattern, which also explains, in palt, its geographical dispersionfrom Peru in the Pacífíc to northern Argentina in the Atlantic.