Morphological and functional study of the marginal sphincter of the sea anemones Phymactis clematis and Aulactinia marplatensis from intertidal of Mar del Plata, Argentina

Abstract

ABSTRACT. It was made the characterization of marginal sphincter to the species Phymactis clematis (Drayton in Dana, 1849) and Aulactinia marplatensis (Zamponi, 1977), from intertidal ecosystem through their morphogical and functional study. The species P. clematis has a circumscript sphincter of palmate type. This muscle is constituted by a mesogloeal axis and several mesogloeal subaxes. Axis as well as subaxes give a support to the endoderm which border is smooth. Aulactinia marplatensis has a circunscript sphincter pinnate type. The axis has a truncated cone shape while in P. clematis the shape is cylindrical on its origin and it is bifurcated at the end. Both species experiments were carried out using the isolated muscles. They were stimulated at increasing KCl concentrations ranging from 20 to 200 mM. The results were analysed in the form of dose-response curves expressed in tension in grams force vs concentration. Contractil force increases in a sigmoid form to increasing KCl concentrations. The correlation between morphology and function and the differences shown in both species would be related to their intertidal distribution.

Molecular and morphological evidence thatPhymactis papillosafrom Argentina is, in fact, a new species of the genusBunodosoma(Cnidaria: Actiniidae)

“…Many studies have been conducted about the morphological, functional and biochemical characterization of the sphincter of B. zamponii sp. nov. (Patronelli et al , 2005, 2008; Olivera et al , 2009).…”

“…Phymactis clematis ; Zamponi, 1977: 139,141 (Argentina); Pollero, 1983; Patronelli et al , 1987; Zamponi, 1989, 1993, 2000, 2005; Excoffon & Zamponi, 1991; Acuña & Zamponi, 1995, 1996, 1997; Acuña et al , 1996; Zamponi & Perez, 1996, Genzano et al , 1996; Acuña, 1997; Zamponi et al , 1998a, b; Gomes et al , 1998; Excoffon et al , 1999; Patronelli et al , 2005, 2008; Olivera et al , 2009; not Phymactis clematis (Drayton in Dana, 1846: 130).…”

“…Phymactis papillosa has also been recorded in Argentina (as P. clematis ), where it is a very common sea anemone species distributed along the coast of Mar del Plata (Zamponi, 1977; Acuña & Zamponi, 1996; Zamponi & Perez, 1996; Oliveira et al , 2009). However, the specific status of these populations has been questioned (Haussermänn, 2004).…”

“…Scale bar: 10 mm.characterization of the sphincter of B. zamponii sp. nov (Patronelli et al, 2005(Patronelli et al, , 2008Olivera et al, 2009)…”

Digestive flexibility in response to environmental salinity and temperature in the non-symbiotic sea anemone Bunodosoma zamponii

“…Because of living in the intertidal area, it is exposed to seasonally and abrupt daily changes in salinity and temperature (Patronelli et al, 2005). Several studies have been conducted on this species (Excoffon & Zamponi, 1991;Acun ˜a, 1993;Acun ˜a & Zamponi, 1995Olivera et al, 2002, Zamponi, 2007Zamponi & Deserti, 2009;Zamponi, 2011;Gomes et al, 2012;Olivera et al, 2012), but none yet on digestive physiology at the biochemical level. In the natural ambient, B. zamponii behaves as a polyphagous opportunistic consuming varied dietary items in relation to food availability.…”