Thoosa Hancock, 1849

Pacheco, Cristian, Carballo, José Luis, Cortés, Jorge, Segovia, Johanna & Trejo, Alejandra, 2018, Excavating sponges from the Pacific of Central America, descriptions and a faunistic record, Zootaxa 4370 (5), pp. 451-491 : 476-477

Genus Thoosa Hancock, 1849

Synonymy. Annandalea Topsent, 1928 (junior synonym). Annandalena Topsent, 1932 (junior synonym). Thooce Laubenfels, 1936 (junior synonym). Not Thoosa sensu Topsent (1888) .

Diagnosis. Sponges always in alpha morphology, with wide array of different spicule types including monaxons such as tylostyles and oxeas as megascleres. Tylostyles only in some species, and occasionally missing in some specimens or populations. Microscleres most commonly as amphiasters, oxyasters and their derivates. Amphiasters mostly tylote, with microspination on all extremities, but variations in different species include smooth oxeote rays.

Oxyasters with small centre, rays commonly reduced, leading to centrotylote sigmoid or tylostylote forms. Biradiate forms can appear like birdwings (adapted from Carballo et al. 2004).