T. Roethig, C.R. Voolstra
Galaxea, Journal of Coral Reef Studies, 18(1), pp. 1-2, (2016)
The marine barrel sponge Xestospongia testudinaria (Lamarck, 1815; Demospongiae; Haplosclerida) has a wide distribution in the Indo-Pacific according to the, World Porifera, database (van Soest 2008). Its size and oftentimes exposed habitus makes it a prominent member of the benthic communities. In Indonesian waters, a mass spawning event of this species has been previously described for the Banda Sea (Sarano 1990). The author described a synchronized event in the morning hours of 29th of August 1989 (one day before new moon) in which X. testudinaria specimens released clouds of gametes into the water column. Further spawning has been observed early in the year 2012, but no details have been reported (Swierts et al. 2013). Another species from the same genus, Xestospongia muta has been observed to release eggs and sperm from 8.00h to 9.00h on March 30, 2004 in Belize (Ritson-Williams et al. 2005).