Reproductive patterns of fungiid corals in Okinawa, Japan

Abstract

The reproductive modes of corals in the family Fungiidae are relatively poorly known. In this study we document the findings over five years of observations of various reproductive traits and seasonal reproductive patterns of 12 species of mushroom corals from northern Okinawa. We provide new records with respect to sexuality and mode of reproduction for six species: Ctenactis crassa, Fungia paumotensis, F. scruposa, F. granulosa, Halomitra pileus and Sandalolitha dentata. Furthermore, we indicate two new species that change sex (C. crassa and F. scruposa), as well as identify F. fungites in Okinawa as a gonochoric brooder. We estimate the reproductive effort of C. echinata, C. crassa and F. repanda for the months of July and August of the years 2007-2009, discuss their diurnal rhythms, degree of spawning overlap and the potential for hybridization vs. temporal reproductive isolation in these species. We conclude by highlighting the fungiids as ideal model organisms for studies of reproductive ecology, larval development and the evolution of life-history traits.