Schizomavella tenella ( REUSS , 1847)

ZÁGORŠEK, KAMIL, 2010, BRYOZOA FROM THE LANGHIAN (MIOCENE) OF THE CZECH REPUBLIC PART II: SYSTEMATIC DESCRIPTION OF THE SUBORDER ASCOPHORA LEVINSEN, 1909 AND PALEOECOLOGICAL RECONSTRUCTION OF THE STUDIED PALEOENVIRONMENT, Acta Musei Nationalis Pragae Series B 66 (3 - 4), pp. 139-255 : 139-255

Schizomavella tenella ( REUSS, 1847)

Pl. 102, Fig. 1-4

v. * 1847 Cellepora tenella m. – Reuss p. 89, Pl. 11, Fig. 16 partim 1977 Schizomavella tenella ( REUSS, 1847) – Vávra p. 126 2007 Schizomavella tenella ( REUSS, 1847) – Zágoršek et al.

p. 211, Fig. 8A-B (cum syn.)

T y p e: Holotype deposited in the Natural History Museum Vienna under the number 1846.37.998 (identified by David and Pouyet, 1974).

M a t e r i a l: 40 specimens studied in detail; plus an additional one showing a different arrangement of the avicularia.

D i a g n o s i s: Colony encrusting, unilaminar with autozooecia arranged in parallel rows. Autozooecia are rectangular to oval, with a flat frontal wall. Frontal wall is perforated by small pseudopores (diameter about 10 µm). Lateral walls are wide, always very prominent and raise between adjacent autozooecia. Apertures have a wide sinus, oral spines are absent. Avicularia are adventitious, suboral with a pivotal bar, they are always situated proximally and very close to the aperture in a median position, tapering proximally and associated with a small umbo. The umbo is always nonporous. Ovicells are hyperstomial, large, about half to one third of the size of the autozooecia, with a strongly porous frontal wall. The pores which perforate the ovicells have the same diameter as those perforating the frontal wall.

R e m a r k s: Only one specimen from the section Kralice nad Oslavou shows a different position of the avicularia: close to the lateral walls (Pl. 102, Fig. 4). Due to the presence of all other characteristic features, mainly the identical structure of the ovicells (porous frontal wall), and this specimen is also identified as Schizomavella tenella ( REUSS, 1847) . For a detailed discussion of this species see Zágoršek et al. (2007).

Superfamily Schizoporelloidea JULLIEN, 1883