LARVAL DEVELOPMENT OF THE ORAL BROODING CARDINALFISH APOGON RUEPPELLII (TELEOSTEI APOGONIDAE) IN WESTERN AUSTRALIA

WA Museum Records and Supplements | Updated 1 decade ago

Abstract: Late stage eggs and the development of the planktonic larvae of the oral brooding apogonid. Apogon rueppellii are described and illustrated using material collected in the Swan Estuary, in south-western Australia. The eggs (2.2-2.5 mm) are nearly spherical and contain the embryos coiled with the tail covering the right eye. The larvae examined (5.5-16.3 mm) are pelagic, lightly pigmented, have a moderately deep body, a compact, coiled gut which extends to about midbody, a large, conspicuous gas bladder and 24 myomeres. Apogon rueppellii larvae are unique among previously described apogonid larvae in that they hatch in an advanced postllexion stage, possessing a yolk sac, functional mouth, developed eye and completely formed second dorsal, anal and caudal fins. The first dorsal and pelvic fins form during their short planktonic life and individuals settle at about 16 mm. It is suggested that both the advanced stage of development at hatching and short planktonic life contribute to maxi mile their survival and retention within the estuary. Comparisons with similar taxa and the early life history of other oral brooding apogonids are also presented.