Larval development of the subantarctic squat lobster Munida subrugosa (White, 1847) (Anomura: Galatheidae), reared in the laboratory.

PATRICIA PEREZBARROS,; SVEN THATJE,; JAVIER CALCAGNO,; GUSTAVO ALEJANDRO LOVRICH

JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY

Elsevier

Año: 2007 vol. 352 p. 35 - 41

0022-0981

The larval development of the squat lobster Munida subrugosa from subantarctic waters of the Beagle Channel (Tierra del Fuego, Argentina) was studied under controlled laboratory conditions of temperature, salinity, and food supply. Developmental times, survival, and growth of larvae and early juveniles were investigated. Hatching of the entire brood always occurred during one night. Larvae were kept in 100 ml individual bowls with filtered seawater at 8 ± 0.5ºC and fed with Artemia spp. nauplii three times a week. Larvae passed through 6 zoeal instars and one megalopa. Previously, only five zoeal instars were known from this species. Mean cumulative durations of the zoeal stages I to VI were: 20.5±2.5, 33.9±4.1, 43.3±5.4, 52.6±5, 61.2±3.9, and 83 days, respectively. By adding the 28 days that a single megalopa took to metamorphose to crab I stage, the complete larval development lasted 111 days. Highest mortality occurred prior to the moult from the zoea I to zoea II stage (79.21% ± 18.65%) and during the moult from zoea VI to megalopa (92.86%). Carapace length was 1.64±0.06, 1.52±0.16, 1.57±0.26, 1.64±0.21, 2.11±0.35, and 2.58±0.19 mm, for zoeal stages I to VI, respectively. Carapace length of megalopae and crab I instars was similar (2.85±0.28 and the 2.84±0.05, respectively). Unlike other subantarctic decapods, which show a tendency towards abbreviated larval development and/or some degree of endotrophy, M. subrugosa shows an extended planktotrophic larval development synchronized with short seasonal plankton production in austral summers.