Studies on Sexual Reproduction of Two Reef Building Corals Seriatopora hystrix and Lobophyllia corymbosa in the Jeddah Coast of Red Sea

Abstract

In Sharm Ubhur, the sexual reproduction of the scleractinian corals Seriatopora hystrix and Lobophyllia corymbosa was investigated for a year. S. hystrix is hermaphrodite brooders with internal fertilization and larvae development within their polyps, according to the researchers. The L. corymbosa, on the other hand, is a hermaphrodite broadcaster with external larval development, therefore embryos are not visible in histological investigations. The reproductive period of S. hystrix was discovered to be limited (January to April). The quantity of eggs and testes seen during this time was also low, and the first planula larvae were discovered in March at a temperature of 27.42⁰C. The gonads in L. corymbosa polyps were found all year, with two cycles of oogenesis and one cycle of spermatogenesis. The S. hystrix egg size was ranged from 158 \(\mu\)m (in January) to 241 \(\mu\)m (in April). The first visible size of eggs of L. corymbosa were observed in August (187.2 \(\mu\)m) and in April (689.96 \(\mu\)m). In S. hystrix, zooxanthellae were found in mature oocytes. They were not found in L. corymbosa