Tornipora Jürgensen, 1971

Taylor, Paul D., Martha, Silviu O. & Gordon, Dennis P., 2018, Synopsis of ‘ onychocellid’ cheilostome bryozoan genera, Journal of Natural History (J. Nat. Hist.) 52 (25 - 26), pp. 1657-1721 : 1705-1706

Genus Tornipora Jürgensen, 1971

( Figure 32 )

Type species

Semieschara canui Brydone, 1906 , by original designation. Cretaceous, Campanian Chalk, Trimingham, Norfolk, England .

Diagnosis

Colony encrusting. Autozooids subhexagonal, rounded distally; zooidal boundaries grooved ( Figure 32 (a,b)). Cryptocyst extensive, granular. Gymnocyst lacking. Opesia terminal, occupying about one-third of frontal surface; wider than long, trifoliate, with deep opesiular indentations and knob-like lateral constrictions; oral spines usually numbering six, arranged in a crescent distally and distolaterally of the opesia. Ovicells unknown? Avicularia vicarious ( Figure 32 (c)), slightly smaller than an autozooid; opesia subcircular; rostrum short, spatulate, rounded distally, floor pustulose.

Remarks

Tornipora was introduced by Jürgensen (1971) for some Cretaceous and Paleocene species often assigned to Floridina on account of their trifoliate opesia but differing in having oral spines. The four species placed in his new genus by Jürgensen (1971) were distinguished mainly on the basis of the size of the autozooids and the number of oral spines. The original diagnosis of the genus noted the presence of ovicells but these were neither described nor figured and have not been seen by us.

Range

Cretaceous (Campanian) to Paleocene (Danian).

Figures

Figure 32. Tornipora canui (Brydone); Cretaceous, late Campanian (Belemnitella mucronata Zone), Trimingham, Norfolk, England, United Kingdom; NHMUK D8000, Brydone Collection; (a) autozooids and an avicularium; cowl-like structure marked by an arrow may be an intramural avicularium budded within an autozooid; (b) autozooids showing lateral constrictions in the opesiae and oral spine bases; (c) autozooid (left) and avicularium (right). Scale bars: a = 500 µm; b, c = 100 µm.