Reproductive biology of the polychaeteKefersteinia cirrataKeferstein (Hesionidae). II. The gametogenic cycle and evidence for photoperiodic control of oogenesis

Photoperiodic regulation of gametogenesis in the Antarctic sea starOdontaster validusKoehler: Evidence for a circannual rhythm modulated by light

“…Changing day-length also has been found to influence reproduction in sea urchins (Pearse et al, 1986b;McClintock and Watts, 1990;Walker and Lesser, 1998) and polychaetes (Chu and Levin, 1989;Fong and Pearse, 1992). Other work on photoperiodic control of gametogenesis in marine invertebrates involved fixed-length photoperiods, and animals responded to either "long-day" or "short-day" photoperiods (e.g., Garwood and Olive, 1982;Olive and Pillai, 1983;Bay-Schmith and Pearse, 1987;Spirlet et al, 2000), combinations thereof (Clark, 1988;Kelly, 200 l), or rectilinear transitions between fixed photoperiods (Olive et al, 1998). Similarly, when individuals of 0. validus were maintained on fixedlength photoperiods of 12L: 12D and continuous light, gametogenesis was disrupted, and both active gametogenesis and numerous gametes were seen in summer as well as winter.…”

“…The possible role of seasonally changing nutrition in regulating the timing of gametogenesis in marine invertebrates remains unclear (Giese and Pearse, 1974;Walker and Lesser, 1998). On the other hand, photoperiod has been experimentally demonstrated to regulate the timing of gametogenesis of many shallow-water temperate and tropical marine species (Richard,197 1 ; Garwood and Olive, 1982; Pearse and Eemisse, 1982; Olive and Pillai, 1983; Pearse and Beauchamp, 1986; Pearse and Walker, 1986;Pearse et al, 1986% 1986b; Steele and Steele, 1986; Bay-Schmith and Pearse, 1987;Clark, 1988; Chu and Levin, 1989;McClintock and Watts, 1990; Xu and Barker, 1990; Fong and Pearse, 1992; Bingham, 1997;Olive et al, 1998;Walker and Lesser, 1998;Spirlet et al, 2000;Kelly, 2001). In this paper we show experimentally that the timing of gametogenesis in the Antarctic asteroid Odontaster validus Koehler also is regulated by photoperiod.…”

Oogenesis and oocytes

“…In Hesiocaeca methanicola (Eckelbarger et al, 2001), follicle-like cells surround each oocyte so they cannot directly contact the vessel lumina. In other species such as Flabelliderma commensalis (Spies, 1977), Harmothoe imbricata (Garwood, 1981), Diplocirrus glaucus (Olive, 1983), Nephtys hombergii and N. caeca (Olive, 1978), and Kefersteinia cirrata (Olive & Pillai, 1983), oocytes contact the blood vessel lumina but there is no ultrastructural evidence of nutrient transfer. Strong ultrastructural evidence for the direct transfer of nutrients from the circulatory system to oocytes has been documented in Phragmatopoma lapidosa (Eckelbarger, 1979), Streblospio benedicti (Eckelbarger, 1980), Spio setosa (Eckelbarger, unpublished), and Leitoscoloplos fragilis (Eckelbarger, unpublished) where the oocytes have an intimate association with the vessel lumen (Fig.…”

“…In Harmothoe imbricata (Garwood, 1978), Nephtys hombergii and N. caeca (Olive, 1978), Naineris laevigata (Giangrande & Petraroli, 1991), Pholoe minuta (Heffernan & Keegan, 1988), and Hesiocaeca methanicola (Eckelbarger et al, 2001), follicle cells appear to be relatively inactive. In Kefersteinia cirrata (Olive & Pillai, 1983), follicle cells contain abundant RER and Golgi complexes. Follicle cells in the ovary of Phragmatopoma lapidosa store glycogen and lipids (Eckelbarger, 1979), those of Streblospio benedicti contain extensive arrays of RER and active Golgi complexes (Eckelbarger, 1980) (Fig.…”

Reproductive biology and population ecology of the marine fan wormSabella pavonina(Savigny) (Polychaeta: Sabellidae)

“…Synchronisation of gamete development requires exogenous factors, or environmental cues, to produce gravid animals at a given time at the population level (e.g. Olive and Pillai 1983). Changes in environmental conditions are known to synchronise gamete development in a number of polychaete populations and seasonal variations in temperature and relative day length have been identified as particularly important cues (see Bentley and Pacey (1992) for review).…”