Published online by Cambridge University Press: 20 May 2016
This paper presents sponges from the Late Cretaceous El Rayo Formation, Puerto Rico. Siliceous sponges are common fossils in the Late Cretaceous of Europe (see for example Schrammen, 1910–1912; Moret, 1926; Weidenmayer, 1994; Pisera, 1999). So far only rare siliceous sponges from the Late Cretaceous of the Caribbean region have been reported: lithistid ?Jerea Lamouroux, 1821, hexactinellids Ventriculites Mantell, 1822, and Plocoscyphia Reuss, 1846 from Trinidad (Thomas, 1935; Trechmann, 1935), and Callopegma Zittel, 1878 from the Cariblanco Formation, Puerto Rico (Howell, 1966). The sponges studied by us are heavily silicified and thus only their approximate determination was possible, but among bodily preserved sponges they are undoubtedly lithistids with tetraclone and rhizoclone desmas. Among loose spicule material, fragments of hexactinellid skeleton dominate, tetraclone and dicranoclone lithistids desmas are common, and hexactinellid lychniscosid skeletons are very rare.