Sakalavastraea poctai ( ELIÁŠOVÁ , 1991)

Löser, Hannes & Sklenář, Jan, 2015, The Scleractinian Coral Genus Glenarea (Bohemian Cretaceous Basin), Acta Musei Nationalis Pragae Series B 71 (3 - 4), pp. 365-376 : 371-374

Sakalavastraea poctai ( ELIÁŠOVÁ, 1991)

Material

CGS-HF2479 (holotype) , ERNO-L4727 ; 1 thin section.

Synonymy

* 1991 Glenarea poctai sp. n. – Eliášová, p. 100, pl. 1: 2, pl. 2: 1, 2, pl. 3: 1, pl. 4.

v non 1998 Glenarea poctai ELIÁŠOVÁ, 1991 – Baron-Szabo, p. 138, pl. 1: 4, 6 [= Lithostrotionoides sp. ]. Dimensions

( CGS-HF 2479)

clmin 2.75–3.45

clmax 3.7–4.3

s 24

(BSPG-2003 XX 4727)

clmin 2.45–3.25

clmax 3.0–3.6

ccd 2.6–4.1

s 21–30

Remarks

The thin sections of the type specimen were not available for study. Measurements are according to the illustration in Eliášová (1991).

Occurrence

Upper Cenomanian, Guerangeri Zone, Korycany and Netřeba localities, and Plenus zone, Kopeč locality.

?Suborder Heterocoeniina BEAUVAIS, 1974 Triphyllocoenia group

Diagnosis

Cerioid colonies. Septa compact, thick, of low number and irregular in two generations. Microstructure lamellar, non-trabecular. Wall has the same structure like septa. Pali, columella, synapticulae, endotheca, and coenosteum absent.

Genera

Ewaldocoenia OPPENHEIM, 1921 ; Glenarea POČTA, 1887 ; Triphyllocoenia ORBIGNY, 1849 .

Systematic position

The systematic position of these genera is preliminary. The thick septal structures, the low number of septa and the absence of any central structures make comparison with the Heterocoeniina suborder possible. Arguing against this assignation is the absence of any septal ornamentation, the obvious non-trabecular microstructure of the septa, and the septal wall. The genera cannot be assigned to any family and are here gathered in an informal group.

Remarks

Calicular openings are wider than the calices in thin sections, producing differing results when measurements are taken from the calicular surface or from thin sections.

Range

Cenomanian to Eocene.

Distribution

Europe.

Glenarea POČTA, 1887

Type species

Glenarea cretacea POČTA, 1887 , by monotypy.

Description

Cerioid colony. Calicular outline polygonal and elongated, centres depressed. Septa compact. Septa in cross-section thick close to the wall, thinner toward the centre. Symmetry of septa irregular, but two generations can be distinguished. First generation reaches about 20% of the larger calicular diameter, the septa of the second generation are much shorter. Septa not connected to each other. Septal upper margin smooth, lateral face smooth, inner margin smooth. Pali or paliform lobes, costae, synapticulae, columella, and endotheca absent. Wall compact, probably septothecal. Coenosteum absent. Budding extracalicinal.

Comparison

Judging from its outer appearance, Glenarea is very similar to the other genera of the informal group. Its type species differs only by larger dimensions. Thin sections were not obtained from Glenarea cretacea because, on the one hand, the specimen is unique and, on the other, it is not very probable that the silicified material would provide much information on its fine skeletal structure.

Species

Only the type species. Glenarea poctai ELIÁŠOVÁ, 1991 belongs to Sakalavastraea . Glenarea jurensis KRASNOV, 1964 belongs to Acanthogyra . Glenarea prozorovskii KUZMICHEVA, 1987 was later assigned to the genus Polypetalum KUZMICHEVA, 2002 . Most Late Cretaceous material assigned to the genus Glenarea belongs to Lithostrotionoides ALLOITEAU, 1952 . Glenarea cretacea in Turnšek and Buser (1974) is not recognisable.

Distribution

Lower Upper Cretaceous of Bohemia ( Czech Republic).

Glenarea cretacea POČTA, 1887

Text-fig. 4

Type

NM-O7541 , holotype by monotypy .

Material

Only the type specimen.

Synonymy

* v 1887 Glenarea cretacea nov. spec. – Počta, p. 25, text-figs 9, 10.

1911a, b Glenarea cretacea, POC. – Frič, p. 63, text-fig. 265 [= refig. Počta, 1887].

non 1974 Glenarea cretacea POCTA – Turnšek et Buser, pp. 20, 36, pl. 10: 2.

v non 2000 Glenarea cretacea POCTA, 1887 – Baron-Szabo, p. 111, pl. 4: 2 [= Lithostrotionoides sp. ].

v non 2006 Glenarea cretacea POCTA, 1887 – Baron-Szabo, p. 76, pl. 15: 5, pl. 16: 3 [= Lithostrotionoides sp. ].

Dimensions

( NM-O 7541)

n min–max µ s cv µ±s

cl min 20 3.13–4.59 3.87 0.45 11.7 3.41–4.32 cl max 20 4.61–7.32 5.94 0.79 13.3 5.15–6.73

s 15 4 –7 5.06 0.79 15.7 4–6

Occurrence

Lower Upper Cretaceous of the Czech Republic (Ústí nad Labem region), Teplice, Řetenice [= Teplitz, Settenz in older literature in the German language].

Triphyllocoenia ORBIGNY, 1849

Type species

Triphyllocoenia excavata ORBIGNY, 1849 , by monotypy. Valid through combined description of a new genus and species.

Description

Cerioid colony. Calicular outline polygonal and elongated, calices small, centres depressed. Septa compact. Microstructure of septa laminar, non-trabecular. Septa in cross-section thick close to the wall, thinner toward the centre. Symmetry of septa irregular. No septal generations or cycles. Number of septa very low (<10). First septal cycle (generation) reaches 30% of the calicular diameter, later cycles (generations) are shorter. Septa not connected to each other. Septal upper margin smooth, lateral face smooth, inner margin smooth. Pali or paliform lobes, costae, synapticulae, and columella absent. Endotheca unknown. Wall compact, structure same as septa. Coenosteum absent. Budding extracalicinal.

Systematic position

The systematic position of Triphyllocoenia was never fixed. Milne Edwards (1857: II, 254) put it into synonymy of Stylocoenia emarciata, (LAMARCK, 1816) . Vaughan and Wells (1943) put the genus in synonymy of Stylocoenia and was followed by Alloiteau (1952) and Wells (1956). Barta-Calmus (1973) did not mention the genus or the type species. Ewaldocoenia was assigned to the Cyathophoridae VAUGHAN AND WELLS, 1943 by Vaughan and Wells (1943); they compared it to Heterocoenia MILNE EDWARDS AND HAIME, 1848 , a genus included at the time in the Cyathophoridae . Bendukidze and Chikovani (1962) assigned the genus to the Heterocoeniidae OPPENHEIM, 1930 , whereas Darga (1992) assigned it again to the Cyathophoridae .

Synonym

Ewaldocoenia OPPENHEIM, 1921 with Ewaldocoenia hawelkai OPPENHEIM, 1921 as type species by monotypy.

Species

Triphyllocoenia excavata ORBIGNY, 1850 ; Ewaldocoenia hawelkai OPPENHEIM, 1921 ; Ewaldocoenia pollaplasia DARGA, 1992 ; Alveopora ataresensis ALTUNA et al., 2007 .

Remarks on the species

Ewaldocoenia is a junior synonym of Triphyllocoenia ORBIGNY, 1849 and the type species E. hawelkai OPPENHEIM, 1921 is considered a junior synonym of T. excavata . All four species represent more or less the same calicular dimensions and septal counts. Exact morphometric data of Alveopora ataresensis ALTUNA et al., 2007 and Ewaldocoenia pollaplasia DARGA, 1992 were not available for comparison. Topotypical material of Alveopora ataresensis available at the Museo Geológico del Seminario de Barcelona is poorly preserved and exact measurements were not possible. Ewaldocoenia pollaplasia is also not well preserved, and thin sections are not available.

Distribution

Upper Eocene of Bosnia and Herzegovina, between Gacko and Lukavac; France (Haute Alpes) Ancelles; Germany (Bayern) Bad Reichenhall, Hallturm, Eisenrichterstein; Middle to Upper Eocene of Spain (Aragón) Jaca Basin, Atarés, Spain (Cataluña, Barcelona) Igualada Basin, (Cataluña, Lérida) Tremp-Campo Basin.

Triphyllocoenia excavata ORBIGNY, 1849

Text-fig. 5

Type specimens

Holotype of Triphyllocoenia excavata MNHN-B24232 by monotypy . Syntypes of Ewaldocaenia hawelkai NHM-R22349 and MB-K2491 .

Material

MB-K 2491, MNHN-B 24232, NHM-R 22349; 2 thin sections.

Synonymy

* v 1849 Triphyllocoenia excavata – Orbigny, p. 7.

v 1850 Triphyllocoenia excavata – Orbigny, p. 404.

v 1921 Ewaldocoenia hawelkai – Oppenheim, p. 153, text-fig. 1.

Dimensions

( MNHN-B 24232)

n min–max µ s cv µ±s

cl min 5 1.26–2.03 1.72 0.38 22.2 1.34–2.11 cl max 5 1.76–2.49 2.15 0.29 13.8 1.85–2.44

s 5 4 –7 5.40 1.14 21.1 4–7 ( NHM-R22349 )

n min–max µ s cv µ±s

cl min 15 1.24–2.04 1.72 0.21 12.5 1.50–1.94 cl max 15 1.75–2.62 2.19 0.23 10.6 1.96–2.43

s 10 3 –6 4.20 0.91 21.8 3–5 ( MB-K2491 )

n min–max µ s cv µ±s

cl min 15 0.95–2.06 1.48 0.33 22.4 1.15–1.81 cl max 15 1.42–2.89 2.19 0.38 17.3 1.81–2.57

s 10 4 –6 5.20 0.63 12.1 5–6

Remarks

The measurements of both specimens of E. hawelkai fit perfectly in the values obtained from the type specimen of Triphyllocoenia excavata , type species of Triphyllocoenia . Ewaldocaenia is considered a synonym of Triphyllocoenia . Oppenheim (1921) discussed the relationship between Ewaldocaenia and Triphyllocoenia but because no illustration of the material of Triphyllocoenia was available and he had obviously no access to the type specimen, he preferred to establish a new genus.

Figures

Text-fig. 4. Glenarea cretacea POČTA, 1887, holotype (NM-O7541), a coral surface, b, c, coral surface, detail, d, longitudinal section. Photos a, b, d by L. Váchová, National Museum, Prague. Scale bar 1 mm.

Text-fig. 5. a, Triphyllocoenia excavata D’ORBIGNY, 1849, lectotype (MNHN-B24232), coral surface. b, Ewaldocaenia hawelkai, syntype (NHM-R22349), coral surface. c–e, Ewaldocaenia hawelkai, syntype (MB-K2491), c, coral surface, d, transversal thin section, e, longitudinal thin section. Scale bar 1 mm.