Reteporella ruzenkae, ZÁGORŠEK, 2010

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

Reteporella ruzenkae sp. n

Pl. 134, Fig. 1-3

D i a g n o s i s: Colony robust, branches with six to eight rows of autozooecia. Frontal wall smooth with scattered small areolar pores. Apertures circular, very large, with delicate condyles. No pseudo-spiramen. Avicularia only frontal. Ovicells immersed, no frontal wall preserved. Dorsal side smooth, without any avicularia.

H o l o t y p e: The specimen illustrated on Pl. 134, Fig. 2-3, from the locality Holubice, deposited in the National Museum Prague under number PM2 – P 01788.

P a r a t y p e s: 2 specimens from the locality Holubice, deposited in the National Museum Prague under the numbers PM2 – P 01787 and P 01925 .

A d d i t i o n a l m a t e r i a l: 2 specimens from the localities Hlohovec and Kralice nad Oslavou, deposited in the National Museum Prague within the bryozoan collection .

D e r i v a t i o n o m i n i s: Derived from the nick name of Růžena – Růženka, in honour of Dr. Růžena Gregorová from MZM Brno, who supported my fieldwork.

L o c u s t y p i c u s: Holubice,sampleA/2

S t r a t u m t y p i c u m: Langhian – Lower Badenian.

M e a s u r e m e n t s: (in micro meters = µm; x = = average):

diameter of branch: 643-1312; x = 1025

length of autozooecia: 578-666; x = 612

width of autozooecia: 144-219; x = 193

length of autozooecial aperture: 115-135; x = 126

width of autozooecial aperture: 105-120; x = 113

length of avicularia: 90-92; x = 91

width of avicularia: 47-60; x = 54

D e s c r i p t i o n: Colony robust, reticulating, branches wide, fenestrulae not preserved. Autozooecia in six to eight longitudinal rows, oval, separated by very thin furrows. Frontal walls smooth, flat, with scattered large areolar pores. Apertures circular, very large, slightly longer than

164 wide with delicate, small condyles. No pseudo-spiramen developed. Suboral avicularia absent, frontal avicularia rare, small, oval, no pivot bar observed. Ovicells immersed, no frontal wall preserved. Dorsal side smooth, without any avicularia.

C o m p a r i s o n: This species is similar to Reteporella hluchovensis sp. n. with respect to the generally robust shape of the colony and the rare development of avicularia, it differs however in the absence of suboral avicularia and pseudo-spiramen.

Even though the ovicells’ frontal walls were not preserved, characteristic features such as the absence of suboral avicularia and pseudo-spiramen, as well as the presence of very large, circular apertures with clearly visible condyles clearly distinguish this species from others known from the Miocene.

O c c u r r e n c e: Also in the sections at Kralice nad Oslavou and at Hlohovec.