Tyloporella Voigt 1989
Creators: name: Taylor, Paul D.
name: Martha, Silviu O.
name: Gordon, Dennis P.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Bryozoa
Gymnolaemata
Cheilostomatida
Onychocellidae
Tyloporella

description: Genus Tyloporella Voigt, 1989   
(Figure 33)  
 Type species   
 Tyloporella reussi Voigt, 1989, by original designation. Cretaceous, late Cenomanian (Actinocamax plenus ammonite Zone), Hoher Stein quarry, Dresden-Plauen, Saxony, Germany.   
 Diagnosis   
Colony encrusting, unilamellar (Figure 33 (a,b)). Autozooids pyriform to subhexagonal (Figure 33 (c,d)); zooidal boundaries grooved. Cryptocyst extensive, granular. Gymnocyst, when visible, narrow, surrounding cryptocyst proximally and proximolaterally. Opesia terminal, occupying about one-third of the frontal surface, semielliptical; two or three pairs of minute oral spine bases in a few autozooids; closure plates often bearing impressions of opercular occlusor muscles present in some zooids (Figure 33 (c,d)). Ovicells hyperstomial (Figure 33 (a)). Avicularia interzooidal, small, irregularly interspersed among autozooids (Figure 33 (a,c)), located distally or laterodistally of autozooidal opesiae.  
 Remarks   
 Voigt (1989, p. 59) introduced the genus Tyloporella for a new species – Tyloporella reussi – that had been misidentified by Reuss (1872) as ‘ Membranipora tenuisulca ’ (Reuss, 1846), the latter being a possible candidate for assignment to Aechmellina gen. nov. The name alludes to similarities with Tylopora Lang, 1917, which, however, has pauciserial, ribbon-like encrusting branches. The most recent redescription of T. reussi is by Martha et al. (2017). Apart from the frequent, small avicularia interspersed among the autozooids, a proximal, smooth gymnocyst is characteristic for this genus according to Voigt (1989) and was taken as justification to assign the genus to Calloporidae rather than Onychocellidae by some subsequent taxonomists (e.g. Taylor and McKinney 2006). A gymnocyst is visible only in some better preserved specimens from the type locality, but not in the holotype, which is poorly preserved. Possible minute spine bases were observed in few autozooids of the holotype colony (Voigt 1989, p. 8, fig. 4), while other, better preserved, colonies show no evidence for spine bases (see Martha et al. 2017).   
 The North American Maastrichtian species Tyloporella cretacea (Canu and Bassler, 1926) has opesiae that occupy about half of the zooidal frontal surface and ovicells with a smooth gymnocystal ooecium (Taylor and McKinney 2006). A third species, Tyloporella smithi Di Martino and Taylor, 2013, from the Campanian of the United Arab Emirates, is bifoliate and can only be placed in this genus with some reservation, as is true for the specimen of Amphiblestrum elegans (von Hagenow, 1851) figured from the Danian of Denmark by Berthelsen (Berthelsen 1962, p. 9, fig. 3).   
 Range   
Cretaceous (Cenomanian to Maastrichtian),?Paleocene (Danian).
description: Published as part of Taylor, Paul D., Martha, Silviu O. & Gordon, Dennis P., 2018, Synopsis of ' onychocellid' cheilostome bryozoan genera, pp. 1657-1721 in Journal of Natural History (J. Nat. Hist.) (J. Nat. Hist.) 52 (25 - 26) on pages 1706-1708, DOI: 10.1080/00222933.2018.1481235, http://zenodo.org/record/4747141