In many viviparous sponges embryonic development is accompanied by deep destruction of aquiferous system (see section ). In the first case, sponges are usually dioecious, while in the second, often hermaphrodites. Sexual reproduction is fundamentally no different from similar processes in other multicellular animals. 2008).įor sponges, both asexual and sexual reproductions are characteristic. However, research on the Caribbean giant barrel sponge Xestospongia muta suggests that this species might be capable of living more than 2000 years (McMurray et al. Their organization is particular they have no distinct gut, muscles, gonads, nervous system, or respiratory system however, sponges have a complex system of canals and chambers for water pumping – the aquiferous system ( Table 2.1).Īge approximations of sponge species range from several months in freshwater sponges to 100 years in some marine sponges.
The body size of sponges varies as much as their body shapes, from 3–10 mm to 1.5–2 m. The body shape of sponges is very diverse they may be film‐like, encrusting, lumpy or spherical, tubular, branching, flabellate, etc. Sponges are aquatic, mostly marine, sedentary multicellular animals, with filtration feeding and respiration. Sponges form a monophyletic group with two clades: Demospongiae + Hexactinellida and Calcarea + Homoscleromorpha. Phylum Porifera comprises classes Demospongiae, Calcarea, Homoscleromorpha, and Hexactinellida. The Porifera represent one of the most diverse taxa of sessile invertebrates with over 9000 extant species. Sponges (Porifera) belong to an ancient metazoan lineage that represents one of the earliest branches of the animal tree (Simion et al. Alexander Ereskovsky 1,2,3 and Andrey Lavrov 2,4ġ Institut Méditerranéen de Biodiversité et d’Ecologie Marine et Continentale (IMBE), Aix Marseille University, CNRS, IRD, Avignon University, Marseille, FranceĢ Department of Embryology, Faculty of Biology, Saint‐Petersburg State University, Saint‐Petersburg, Russiaģ Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, RussiaĤ Pertsov White Sea Biological Station, Biological Faculty, Lomonosov Moscow State University, Moscow, Russia
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