Sexual reproduction of a low-temperature tolerant coral Oulastrea crispata (Scleractinia, Faviidae) in Hong Kong, China

Abstract

In December 1993, an experimental artificial reef made of pulverised fuel ash (PFA) and concrete was deployed at Hoi Ha Wan Marine Park, Hong Kong. The reproductive biology of Oulastrea crispata, the pioneer species recruited onto the structure, was studied to ascertain its reproductive strategies, including its gametogenic cycle in terms of oocyte and spermary development and timing of planula release. A histological study showed that O. crispata was hermaphroditic and had an annual gametogenic cycle with an extended spawning period from July to October. Planulae were released in the resting period of the gametogenic cycle. With an opportunist life history trait, including a wide range of reproductive strategies, O. crispata is able to colonize a variety of substrata, including those unfavourable to other corals, and to flourish as the pioneer colonizer of newly immersed structures.

Sexual reproduction in the Mediterranean solitary coral Balanophyllia europaea (Scleractinia, Dendrophylliidae)

“…The oral-aboral distribution of Balanophyllia europaea gametogenetic processes is in some ways analogous to that found in other hermaphroditic polyps of freshwater hydras (Stagni 1974, Vannini 1974, Grassi et al 1995, the octocoral Heteroxenia fuscenses (Achituv & Benayahu 1990) and the scleractinian corals Stylophora pistillata (Rinkevich & Loya 1979) and Oulastrea crispata (Lam 2000). Freshwater hydrozoans, and anthozoans, are characterized by the presence of nervous cells throughout their entire body; it has been hypothesized that the neurosecretory activity of these cells is responsible for determining the sexual gonad distribution along the polyp's oral-aboral axis (Schaller 1973, Schaller & Gierer 1973, Stagni 1974).…”

“…The studies hitherto conducted on the annual cycle of sexual reproduction in scleractinian corals refer almost exclusively to tropical and subtropical species (Fadlallah 1983b, Harrison & Wallace 1990, Richmond & Hunter 1990, Richmond 1997, Lam 2000, with few data on reproduction in temperate species (Stoddart & Black 1985, Ward 1992, Beauchamp 1993, and references therein). In particular, for species living in the Mediterranean, information is available only from the 19th century, on Caryophyllia smithi, Astroides calycularis, Balanophyllia regia, B. pruvoti and Cladopsammia rolandi (Lacaze-Duthiers 1873, 1897, and from the last few years on B. europaea (Goffredo & Telò 1998, Goffredo et al 2000.…”

First record of the Central Indo-Pacific reef coral Oulastrea crispata in the Mediterranean Sea

“…Previously, it had a central Indo-Pacific distribution, ranging longitudinally from Sri Lanka in the central Indian Ocean to the Solomon Islands in the West Pacific and latitudinally from Honshu (Japan) in the north to the Abrolhos-Houtman Islands (West Australia) in the south (Veron, 2000). Owing to its dark skeleton pigmentation (Kawaguti & Sakumoto, 1952;Kawaguti, 1985) and outstanding white septa in retracted polyps, it has been nicknamed "Zebra Coral" (Lam, 2000a;Yamashiro, 2000;Denis et al, 2012). However, this colour pattern is variable and is not observed in all specimens (Yamashiro, 2000).…”

“…Furthermore, as a simultaneous hermaphrodite, releasing planulae without zooxanthellae, and as producer of asexually derived planulae with zooxanthellae, it is both a broadcast spawner and a planula brooder (Nakano & Yamazato, 1992;Lam, 2000a). Owing to these life history traits, O. crispata appears to be an opportunistic colonizer of various substrates (Lam, 2000b).…”

Quantificação da gametogênese através de análises histológicas para estimar a reprodução sexuada de Madracis decactis Lyman, 1859 (Cnidaria, Anthozoa, Scleractinia) do litoral sul do Estado do Rio de Janeiro

“…SzmantFroelich et al, (1980) também destacaram que o aumento de tamanho dos ovócitos nos últimos estágios era dramático e que o material utilizado para esse crescimento poderia vir da absorção de ovócitos menores enquanto os maiores cresciam. Apesar desse processo parecer bastante comum entre os corais escleractínios (Wyers, 1985;Sier & Olive, 1994;Kruger & Schleyer 1998;Lam, 2000;Pires et al, 2002, Neves & Pires, 2002, algumas espécies de Acropora não apresentaram degeneração de ovócitos em desenvolvimento, sendo o número de ovócitos por pólipo constante do início até o final da ovogênese (Wallace, 1985), enquanto que Tomascik & Sander (1987), estudando Porites porites, consideraram o processo de absorção uma fonte de alimentação pouco importante para o desenvolvimento dos ovócitos.…”