Development
Fertilization of E. quardicolor eggs leads to development of planulae larva. Initially the embryos undergo superficial cleavage followed by cell divisions which are sometimes asynchronous leading to irregular cell counts by the blastulae stage (Scott & Harrison 2007b). As development continues the embryo flattens out, undergoes gastrulation and finally forms a early planulae larvae approximately 14 hours after spawning (Scott & Harrison 2007b). The larvae continues to elongate along the oral – arboreal axis and colour changes from a green to brown, owing to the zooxanthellae, to a orange brown (Scott & Harrison 2007b). Larvae then become mobile, utilizing coordinated cilliary beats to travel directionally at speed up to 6.4 cm per 30 secs (Scott & Harrison 2007b). Larvae reach competency and settle as early as 5 days after spawning, with maximum settlement occurring on the 10th day (Scott & Harrison 2008). However larvae have been found alive and swimming up to 59 days post spawning indicating the potential for wide dispersal (Scott & Harrison 2007b). Upon settlement prior to attachment larvae have been observed crawling along settlement surface and are thought to respond to metamorphic cues from the sediment surface (Scott & Harrison et al 2008). Once attached tentacles begin to grow from out pockets around the oral region enabling the juvenile polyp to beings feeding heterotrophically (Scott & Harrison 2008).
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