New Zealand Journal of Marine and Freshwater Research abstracts
Review Evolution of life cycles, including migration, in spiny lobsters
(Palinuridae)
R. W. George
Centre of Excellence in Natural Resource Management
University of Western Australia
Albany
WA 6330, Australia
email: rage1@iprimus.com.au
Abstract A comparison of the documented ecology and behaviour
of the separate phases in the life cycles is presented. Data gathered during
the review show that during the evolution of the family from deeper-water
habitats to the more rapidly fluctuating shallower waters, there have been
many biological adjustments at each phase in their life cycles. In the more
ancient Stridentes genera, like Puerulus, the larvae are found well
below the surface waters and the pueruli often settle at greater depths than
those of the adults. Long incubation times, few larval instars, and year-round
spawning are probably their life cycle characteristics. As an “intermediate-evolved”
genus of Stridentes, Palinurus lives along the outer shelf, grows
slowly, matures late, and breeds seasonally once a year. Incubation time
is long, the larvae live at depth, the number of larval instars is limited,
and the puerulus is a weak swimmer. Settlement is often downstream of the
breeding stock. Incubation times are short for the more recently evolved
StridentesPanulirus, the larvae pass through many instars in the surface
waters to c. 200 m. Some pueruli settle in special coastal habitats, others
settle in the same habitat as the adult. Breeding in the cooler water First
Major Lineage species is seasonal, one or two broods being produced. Most
of the species in the tropical Second Major Lineage are faster growing, breed
repetitively over a long breeding season, and have a shorter larval life.
For the Silentes, the trend in biological changes from deep to shallower
water is comparable with that of Stridentes. Incubation is probably long
in the more ancientProjasus, the larvae are rare in surface waters
and the pueruli settle at depths similar to those of the adults. Sagmariasus
and Jasus breed once during a defined season, incubation time is moderate,
and the larvae pass through many instars. The pueruli of Sagmariasus
settle downstream and exhibit contranatant migration whereas the pueruli
of Jasus swim strongly to their shallow habitats. In each life cycle
phase, migration methods range from vertical paddling in phyllosomata, horizontal
swimming in pueruli, and horizontal walking when juveniles move to adult
habitats. Adult movements are associated with foraging, searching for shelter,
avoiding adverse seasonal conditions, or walking to preferred offshore locations
for moulting and reproduction.
Keywords evolution; spiny lobsters; Palinuridae; life
cycles; migration strategies
M04099; Online publication date 8 June 2005 Received 23 April 2004; accepted
14 September 2004
New Zealand Journal of Marine and Freshwater Research, 2005, Vol. 39:
503-514
0028-8330/05/3903-0503 © The Royal Society of New Zealand 2005
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