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This study examined the reproduction and population structure of the blue-spotted maskray Neotrygon kuhlii within Moreton Bay, a subtropical embayment in south-east Queensland, Australia. Mean sizes at maturity were 314 mm disc width ( WD) in females ( n = 140, 115–465 mm WD) and 294 mm WD in males ( n = 123, 129–381 mm WD). Female N. kuhlii had a synchronous annual reproductive cycle, with one litter of one to three pups (mean ±s.d. 1·67 ± 0·71) produced per year. Mating behaviours were observed in October and November, and ovulation occurred early in the Austral summer, overlapping with the start of embryonic development. Gestation took c. 4 months with parturition occurring in late February and March. Size at birth was 115–170 mm WD. The population showed a significant female bias, particularly in larger size classes. Tagging studies produced a total recapture rate of 16·1% and indicated that N. kuhlii were site resident for up to 1081 days. [ABSTRACT FROM AUTHOR]

Morphological development of the larvae of the Ambon damselfish Pomacentrus amboinensis from the Great Barrier Reef, Australia, is described from 34 reared specimens (2·5–13·0 mm standard length), and two wild settlement-stage larvae (10·8–11·3 mm) captured in light traps. Reared larvae emerged from demersal eggs at c. 2·5 mm, underwent notochord flexion at 4·0–4·5 mm, and settled at 11–13 mm at 19–21 days after hatching (within the known range for wild larvae). Reared larvae grew at 0·3 mm day−1 (preflexion) to 0·5 mm day−1 (postflexion). Development was direct with few specializations for pelagic existence and was typical of pomacentrids. Head spination consisted of very weak spines on the preopercle, opercle, interopercle, subopercle and supracleithrum. Development of the olfactory system and retina are also described. A summary of published descriptions of early life-history stages of pomacentrid damselfishes is provided ( n= 15% of known species). Larvae of several genera ( e.g. Abudefduf, Chromis and Stegastes) are deeper-bodied and more ‘hunchbacked’ than P. amboinensis. Larvae of other genera ( e.g. Amblyglyphidodon, Chrysiptera and Neoglyphidodon) are similar to P. amboinensis. Larvae of only three other Pomacentrus species have been described, and they are similar to P. amboinensis in body morphology, pigmentation and head spination. [ABSTRACT FROM AUTHOR]