REPRODUCTIVE SEASONALITY AND SEX CHANGE IN A MARINE PATELLID LIMPET

摘要

Most patellid limpets are dioecious broadcast spawners (Fretter, 1984) with a distinct seasonality of reproduction. South African limpets have been also noted to breed seasonally (e.g. Branch, 1974; Robson, 1986; Lasiak, 1987), with species from the cool temperate southern Atlantic (west coast) exhibiting one spawning period a year, whereas those from the warm temperate to subtropical Indian ocean (southern and east coast) usually having two spawning events. However, not all species are restricted toone biogeographic area, and some species of South African limpet inhabit both cold and warm temperate rocky shores. Populations of such species will thereforebe subjected to very different environmental conditions. To date, all investigations of the reproductive patterns of South African limpets have been single biogeographical, or site, studies.