Hippadenella regularis (REUSS 1874)

Zágoršek, K. & Fordinál, K., 2006, Lower Sarmatian Bryozoa from brackish sediment in the northern part of the Danube Basin (Dubová, Slovakia), Linzer biologische Beiträge 38 (1), pp. 93-99 : 96

Hippadenella regularis (REUSS 1874) Fig. 2 /5

* 1848 Lepralia regularis m. – REUSS p. 168, Pl. 2, Fig. 1

1974 Hippadenella regularis (REUSS) – DAVID & POUYET p. 177, Pl. 10, Fig. 5

1977 Hippadenella regularis (REUSS) – VÁVRA p. 129

M a t e r i a l: Three fragments of erect colonies, with zooecia arranged in regular longitudinal rows. Zooecia have a characteristic convex, granular, nonporous frontal wall perforated marginally by small areolar pores. The orifice is wide with well developed cardelles. A small, circular to key-shaped suboral avicularium is sometimes developed near the proximal margin of the orifice. No ovicells observed.

R e m a r k s: The investigated specimens exhibit all of the characteristic features, mainly the regular growth pattern of the zooecia and small key-shaped suboral avicularium, that are seen in the holotype deposited in the Natural History Museum in Vienna and studied by ZÁGORŠEK (personal investigation). Although this species has never been previously reported from brackish water, its morphology allows a precise determination.

D i s t r i b u t i o n: Badenian (Miocene): Vienna basin: Podivín (Czech – REUSS 1874), Carpathian Foredeep: Kralice nad Oslavou, Židlochovice and Holubice (Czech – personal observation of ZÁGORŠEK).

Superfamily Celleporoidea JOHNSTON, 1838

Family Celleporidae JOHNSTON, 1838

Genus Celleporina GRAY, 1848

Figures

Fig. 2: Bryozoa: (1-2) Tubulipora cumulus (Sinzow 1892). Note marked concentric grown lines, apertures arranged in fascicles and porous frontal walls. (3) Hippadenella regularis (Reuss 1874). General view showing wide apertures with characteristic key-shaped suboral avicularium (visible on lower rows of zooecia). (4) Hippopleurifera cf. semicristata (REUSS 1848), fragment of colony with characteristically developed apertures and large pores on frontal wall. (5) Celleporina sp. general view showing small suboral avicularia, lateral areolar pores and ovicells with semicircular windows. (6) Schizoporella tetragona (REUSS 1848). Detail of few zooecia with visible characteristic aperture with wide sinus and large oral avicularia with prominent pivotal bar. All pictures were made in Paleontological Institute of Vienna University in SEM Jeol type JSM-6400 by Dr. K. Zágoršek. Scale bar 100 µm.