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ARKHIPKIN A.I.; LAPTIKHOVSKY V.V.; MIDDLETON D.A.J. 《Journal of Molluscan Studies》2000,66(4):551-564
Inshore spawning sites of the cold water squid Loligo
gahiwere found in the waters of East Falkland (Southwest
Atlantic),where there is a major fishery based on this species. Egg
massesoccurred in algal beds, often at the outer (seaward) edge, with
ambientwater temperatures of 6.5-90C and salinity 33.75- 33.58. They
wereattached to the stipes of the kelp algae Lessonia
spp. and Macrocystispyrifera from 0.5 m to 2.5 m off the
bottom at 8-20 m depths.The overall density of egg masses was
low. The egg mass is abundle of elongated gelatinous translucent
capsules with eachcapsule firmly attached to the kelp stipe at its
basal end.The capsules are mainly 50-60 mm in length and contain an
averageof 70 fertilized eggs. Sampled egg masses consisted of 4-161
capsulesand from 138 to 11,487 eggs. Large egg masses (. 50 capsules)
wereapparently formed by several females at different times, as
embryosin different capsules were at various stages of
development.Eggs laid in winter are significantly larger than those
laidin summer. In comparison with tropical and temperate Loligo
spp.L. gahi have short egg capsules containing a small number of
eggs,but the eggs (2.2-2.5 mm diameter) and hatchlings (3.1-3.4 mm
mantlelength) are large. These are probable adaptations for cold
waterspawning and development. (Received 30 March 2000; accepted 5 June 2000) 相似文献
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Fifty-nine specimens of the tropical epipelagic eno-ploteuthidEnoplotcuthis leptura were collected in the central-east Atlanticbetween 19861988. Statoliths were extracted from allspecimens (mantle length (ML) 4.192 mm) and processedunder the statolith ageing technique. The characteristic featureof statolith morphology in E. leptura is a sculpture of therostrum, which is covered by numerous tiny spines and knobs.In the ground statolith it was possible to distinguish fourmain growth zones consisting of narrow growth increments likethose in other squids studied. Allometric growth of statolithsversus ML is negative. E. leptura is a short-lived squid witha half-year life span. Growth rates of E. leptura are high atjuvenile stage (instantaneous rate of growth (G) of body weight(BW) 0.040.06). An early maturation of males (at age4560 days) and females (at 8090 days) causes asharp decrease of somatic growth of E. leptura, and mature squidhave low growth rates (G of BW - 0.OO3-O.0O5). Spawning takesplace between January and September with two peaks: in Januaryand in June-July. (Received 22 November 1992; accepted 15 February 1993) 相似文献
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