Evolution & Systematics

The phylum Porifera is a very successful taxon that stands out because of the high diversity of its members on the one hand and on the other hand because of their importance regarding early metazoan evolution. Ongoing debates about their phylogeny and systematics do not just concern the organization within the phylum itself but also the relationships to other non-bilaterian animals (Wörheide et al., 2012).


One of the assumed phylogenies (abstracted from: Ruppert et al., 2004)

Fossil records of Demospongiae, Calcarea and Hexactinellida lead back to the Cambrian or Ordovician periods (Ruppert et al., 2004). Demospongiae comprises about 85% of all sponge species, are highly diverse and can be found in all oceans and most freshwater habitats (Wörheide et al., 2012).
The order Haplosclerida is comprised of numerous shallow-water marine sponges and all freshwater sponges. Haplosclerida can be divided into three suborders (Haplosclerina, Petrosina, Spongillina) (Van Soest & Hooper, 2002a). Members of the suborder Haplosclerina are featured by a regular anisotropic skeleton and the suborder consists of three families: Chalinidae, Callyspongiidae and Niphatidae (Van Soest & Hooper, 2002b).  Chalinidae, however, are charactericed by a unispicular ectosomal skeleton (De Weerdt, 2002).
Haliclona cymaeformis belongs to the family of Chalinidae.