Izvestiya of Saratov University.
ISSN 1819-7663 (Print)
ISSN 2542-1921 (Online)


ontogenesis

Morphogeneses of the Late Cretaceous Guettardiscyphia (Porifera, Hexactinellida)

Guettardiscyphia skeletons are peculiar for thin walls and highly dense apo- and prosopores. Wall mobility was conductive to formation of conical lobate skeletons of various, occasionally geometrically regular outlines. Substantial number of fossil samples from variously composed rocks from all the Upper Cretaceous intervals has made it possible to trace skeleton transformations in sponge ontogenesis and depending on their environmental conditions.