Cribellopora trasoni, 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

Cribellopora trasoni sp. n.

Pl. 122, Fig. 1-3

D i a g n o s i s: Colony encrusting. Autozooecia oval with small cribellate frontal pores. Lateral walls indistinct. Aperture semilunar with a very narrow sinus, no oral spines. Ovicell flat with a smooth, nonporous frontal wall.

H o l o t y p e: The specimen illustrated on Pl. 122, Fig. 2-3 from the section Kralice nad Oslavou, deposited in the NM Prague under the number PM2-P 01505

P a r a t y p e s: The specimen from the section Kralice nad Oslavou, deposited in the NM Prague under the number PM2-P 01924

D e r i v a t i o n o m i n i s: Derived from the name Třasoň, a student who studied the section at Kralice nad Oslavou.

L o c u s t y p i c u s: Kralice nad Oslavou, sample-4, which corresponds to sample KRA-S 3 ( Zágoršek et al., 2009).

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):

length of autozooecia: 604-719; x = 677

width of autozooecia: 455-515; x = 475

length of autozooecial aperture without sinus:

102-129; x = 114

length of autozooecial aperture with sinus:

147-182; x = 167

width of autozooecial aperture: 146-156; x = 150

length of ovicell: 257-373; x = 302

width of ovicell: 311-387; x = 349

D e s c r i p t i o n: Colony encrusting, autozooecia grow in rather regular rows. Autozooecia usually oval or slightly hexagonal, longer than wide, separated by deep furrows. Frontal wall convex, smooth, slightly perforated by scattered, cribellate frontal pores. Lateral walls indistinct. Aperture semilunar to semicircular with a very narrow sinus, preserved almost as only a slit. No oral spines observed. Ovicell flat, slightly immersed into the distal part of the autozooecium with a smooth, nonporous frontal wall. Marginal pores on the ovicell not developed.

C o m p a r i s o n: This species differs from Cribellopora latigastra ( DAVID, 1949) in having small frontal pores, ovicells without lateral pores and a very narrow sinus. The exact shape of the frontal pores is – due to the preservation – not clearly visible, but they are smaller than in Cribellopora latigastra . Cribellopora hluchovensis sp. n. also has a wide sinus and ovicells with lateral pores.

R e m a r k: Due to the presence of cribellate frontal pores, a narrow sinus and absence of oral spines this species belongs to Cribellopora as described by Gordon (1984).

O c c u r r e n c e: Only in the section at Kralice nad Oslavou.