Abstract
Emended diagnoses encompassing forms described herein are proposed for the family Palaeoscenidiidae and the subfamily Palaeoscenidiinae. Diagnosis of the family Entactiniidae is emended to include only forms with latticed or spongy shells developed around a central spicule. This emendment permits mutual exclusivity of forms of the Palaeoscenidiidae and the Entactiniidae. Five genera of Palaeoscenidiinae are distinguished by skeletal ray arrangement. One of these, Palaeoscenidium, was illustrated previously in the literature. It is here emended to include only skeletons with four apical and four basal rays. Palaeoscenidium bicorne is reassigned to Palaeoephippium n. gen. [type species: P. bifurcum sp. nov.] New genera and erected for (1) five-rayed spicules with one apical ray and four basal rays-Palaeopyramidium [type speices: P. spinosum sp. nov.], (2) six-rayed spicules with two apical rays and flour basal rays-Palaeoephipium, (3) six-rayed spicules with three apical rays and three basal rays-Palaeotripus [type species: P. nudus sp. nov.]; and (4) ten-rayed spicules with two apical rays and eight basal rays-Palaeodecaradium [type species: P. umbelliforme sp. nov.]. Twenty-three new species belonging to the subfamily Palaeoscenidiinae and two new species of the family Entactiniidae are described. The Palaeoscenidiinae are shown to have given rise polyphyletically to the Entactiniidae.

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