Pedal laceration by the anemone Aiptasia pallida

Abstract

The significance of zooxanthellae and feeding regime on pedal laceration by the anemone Aiptasia pallida Verrill was studied in the laboratory by maintaining symbiotic and aposymbiotic individuals at varying feeding regimes. Pedal laceration was inversely related to feeding frequency and the presence of zooxanthellae increased pedal laceration rate of starved individuals. Lacerates produced by symbiotic individuals had a significantly greater dry weight than lacerates produced by aposymbionts. This difference can largely be explained by the presence of zooxanthellae in symbiotic lacerates which comprised 55 to 60 % of lacerate dry weight. Development time and survival of lacerates to juvenile anemones was not significantly different for symbiotic and aposymbiotic lacerates and lacerate dry weight did not change significantly during development. These results suggest that zooxanthellae had little effect on lacerate development but enhanced pedal laceration rate during starvation.

Effects of Cd, Co, Cu, Ni and Zn on asexual reproduction and early development of the tropical sea anemone Aiptasia pulchella

“…results from the parent moving away from a small piece of lacerated pedal disc tissue (Cary 1911;Clayton 1985). Mortality and inhibited development of A. pulchella lacerates may also have occurred due to the production of low-quality offspring by metal-exposed adults (Manzo et al 2010), or because of a higher sensitivity of critical early life-stages following separation from the parent (van Dam et al 2008).…”

“…However, due to the small size of individual lacerates and lack of differentiated muscular tissues, mortality was difficult to define and was recorded when signs of tissue decomposition were evident. A juvenile was recorded if a minimum of eight tentacles of any length could be seen, as described for A. pallida (Cary 1911;Clayton 1985).…”

“…Following separation from the adult, the asexually-reproduced offspring is termed a 'pedal lacerate' and develops into a juvenile within 8 days (Howe et al 2014b). Lacerate development in A. pallida is similarly rapid, with mean development times of 6 and 7 days reported for aposymbiotic and symbiotic A. pallida lacerates, respectively (Clayton 1985). The process of metamorphosis from a lacerate to a juvenile (i.e.…”

A anêmona-do-mar Diadumene Stephenson, 1920: um cnidário com potencial invasor na Baía de Paranaguá, PR, Brasil

“…A reprodução sexuada em cnidários é bastante estudada, mas os processos deste tipo de reprodução podem ser bem menos significativos para a ecologia e evolução dos cnidários do que se acredita, já que em alguns ambientes a reprodução assexuada tem efeitos pronunciados tanto na população quanto na estrutura da comunidade (Clayton, 1985;Fautin, 2002).…”

“…Para Metriduim senile o efeito da disponibilidade de alimento é o mesmo que para D. lineata, pois sua fissão é diretamente relacionada à velocidade da corrente, que também está correlacionada com a disponibilidade de zooplâncton (Shick e Hoffman, 1980) apud (Clayton, 1985). Já para uma anêmona Acontiaria não identificada (posteriormente identificada por Minasian, 1982 como Aiptasiogeton comatus, cujo status é indefinido) e Anthopleura elegantisima (Brandt, 1835) a alimentação diminui a freqüência de reprodução assexuada respectivamente, por laceração pedal e por fissão longitudinal.…”