Pyrisinella, Martino, Emanuela Di & Taylor, Paul D, 2012

Martino, Emanuela Di & Taylor, Paul D, 2012, Pyrisinellidae, a new family of anascan cheilostome bryozoans, Zootaxa 3534, pp. 1-20 : 4

Genus Pyrisinella n. gen.

Diagnosis. Colony encrusting, multiserial, unilaminar. Autozooids small, distinct, rounded polygonal, longer than broad, separated by deep furrows. Gymnocyst convex, narrow, best developed proximally. Cryptocyst extensively developed, depressed, flat and densely granular, bounded by pear-shaped ridge comprising mural rim and distal rim of opesia. Opesia trifoliate. Oral spines present. Ovicell hyperstomial, globular, prominent, smooth with a dumbbell-shaped opening, resting on proximal gymnocyst of distal zooid and indented its mural rim. Intramural buds common. Closure plates depressed beneath level of cryptocyst. Avicularia interzooidal or more commonly adventitious. Distal pore chamber larger than distolateral pore chambers; pore windows oval. Ancestrula having the appearance of a small astogenetically mature autozooid with an indeterminate number of spine bases, budding a single distal zooid.

Type species. Setosinella meniscacantha Taylor & McKinney, 2006 .

Etymology. From the Latin pirum, meaning pear, in reference to the pear-shaped ridge formed by the mural rim and distal rim of the opesia.

Remarks. Important differences between this monospecific genus and the Paleocene type species of Setosinella, S. prolifica Canu & Bassler, 1933 , are the trifoliate shape of the opesia and lack of opesiules.

Distribution. Upper Cretaceous (Maastrichtian) of Alabama, Mississippi and North Carolina, USA.