Investigation of the budding process in Tethya citrina and Tethya aurantium (Porifera, Demospongiae)

Abstract

The budding process has been studied in two congeneric Mediterranean species belonging to Tethya from different sampling sites: Marsala and Venice Lagoons (Tethya citrina); Marsala Lagoon and Porto Cesareo Basin (Tethya aurantium). Buds, connected to the adult by a spiculated stalk, differ between the two species in morphology and size, since those of T. citrina are small with elongated bodies, showing only a few spicules protruding from the apical region, whereas those of T. aurantium are round, larger, and show spicules radiating from the peripheral border. In T. citrina, cells with inclusions, varying in electron density and size, represent the main cell types of the buds. In T. aurantium, the cell component shows a major diversification, resulting from spherulous cells, grey cells, vacuolar cells and peculiar micro-vesicle cells. Neither canals nor choanocyte chambers were observed in the buds of the two species. In T. citrina, bud production is similar in both sampling sites. In T. aurantium, budding occurs more rarely in Porto Cesareo Basin, probably in relation with environmental factors, such as the covering of the cortex by sediment and micro-algae. Finally, in the buds of both species, the spicule size does not differ from that of the cortex of the adult sponges, further supporting the main involvement of the cortex in organizing the skeletal architecture of the buds.

Asexual and puzzling sexual reproduction of the Mediterranean sponge Haliclona fulva (Demospongiae): life cycle and cytological structures

“…These stages are very similar to what was described in T. aurantium (Connes ; Gaino et al. ), R. cerebellata (Saller ), Tethya seychellensis ( Wright 1881) (Gaino et al. ), and in Cinachyrella cavernosa ( Lamarck 1815) (Singh & Thakur ).…”

“…; this work), or after detachment from the parental sponge (Ayling ; Battershill & Bergquist ; Gaino et al. ).…”

“…For instance, budding occurs occasionally in almost all sponge clades and in any type of habitat (Simpson ; Fell ; Gaino et al. ; Teixido et al. ; Ereskovsky & Tokina ; Ereskovsky ), but it is observed regularly among marine representatives of Porifera.…”

A new Mediterranean species ofTethya(Porifera: Tethyida: Demospongiae)

“…By contrast, asexual budding was usually observed in the coexisting T. aurantium and T. citrina through the sampling period (summer) at Taranto, Porto Cesareo and Marsala. Moreover, literature data confirm the high frequency of asexual budding events in many Mediterranean populations of the latter two species (T. aurantium and T. citrina) (Corriero et al 1996(Corriero et al , 2007Gaino et al 2006;Cardone et al 2010). Buds detected from T. meloni are similar in shape and size to those produced by T. aurantium (Table II).…”

Biological variations in a long-term ex situ cultivation: a Mediterranean demosponge as model system

“…Moreover, like most of its congenerics, this species is able to reproduce asexually by budding, both in natural (Corriero et al, 1996;Gaino et al, 2006;Cardone et al, 2010) and ex situ (Cardone et al, 2008) conditions. In natural environments, geographically distant T. citrina popula-tions show different budding periodicity, from a clear seasonality (Marsala and Venice lagoons, Corriero et al, 1996;Gaino et al, 2006) to continuous budding all year round (SW Apulia, Cardone et al, 2010). In the present research, intense budding events took place during the first two months of rearing, after the increase of temperature at which the sponges were subjected when transported from their natural habitat to rearing tanks.…”