Faviina VAUGHAN et WELLS, 1943

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 : 368-371

Suborder Faviina VAUGHAN et WELLS, 1943

Remarks

The suborder Faviina is poorly defined because of nomenclatorical problems. The genus Favia that gives its name to the suborder Faviina and family Faviidae GREGORY was originally established by Oken (1815). With a few exceptions, the taxa established in this publication are unavailable (ICZN Opinion 417; Hemming 1956). Favia was therefore ascribed to Milne Edwards (1857) with Madrepora fragum ESPER, 1795 as type species (see for instance Budd et al. 2012). It is widely ignored that the genus was already used by Ehrenberg (1834). Madrepora fragum was not included in the list of species provided by Ehrenberg (1834) and thus cannot be type species. Favia EHRENBERG, 1834 is therefore without type species and hence undefined.

Diplocoenia group

Remarks

Even if the family Faviidae were accepted in its current conceptual meaning it would be questionable whether Mesozoic coral genera could be assigned to this family. Ranges of its genera are shorter than generally published (see discussion in Löser 2005, 2013). Evolutionary changes in Scleractinian corals were – even if slow – obviously more rapid than the literature reflects and as well the ranges of families are probably shorter. The genus Sakalavastraea is placed here in the informal Diplocoenia group that encompasses Middle Jurassic to lower Upper Cretaceous (Cenomanian) cerioid corals with compact septa, medium-sized trabeculae and no synapticulae. The septa are often and mostly regularly connected to each other, and the columella is generally lamellar or formed by septal fusion. The informal group encompasses the following genera: Bussonastraea BEAUVAIS, 1965 ; Diplocoenia FROMENTEL, 1857 ; Edwardsastraea RONIEWICZ, 1970 ; Melikerona ALLOITEAU, 1958 ; Paraphyllocoenia REIG ORIOL, 1991 ; Placastrea STOLICZKA, 1873 ; Sakalavastraea ALLOITEAU, 1958 ; Septastraeaopsis ALLOITEAU, 1954; Thalamocoenia ORBIGNY, 1850 ; Tricassastraea ALLOITEAU and DERCOURT, 1966 . The genera are partly synonymous.

Sakalavastraea ALLOITEAU, 1958

Type species

Sakalavastraea collignoni ALLOITEAU, 1958 by original designation.

Diagnosis

Cerioid coral colony with small (less than 5 mm) polygonal calices. Septa compact, in a subregular hexameral symmetry. Septa connected to each other. Septal lateral faces with thorns. Columella lamellar or formed by septal fusion. Endotheca well developed. Coenosteum, pali or paliform lobes, and synapticulae absent. Budding extracalicinal.

Description

Cerioid colony. Calicular outline polygonal, slightly enlarged, larger diameter less than 5 mm, calicular pit depressed. Septa compact. Microstructure of medium-sized trabeculae. Septa in cross-section slightly thicker close to the wall, becoming slightly thinner towards the centre. Septal maximum thickness ca. 200 µm. Symmetry of septa radial and irregularly hexameral. Cycles of septa subregular formed in two to three cycles. Septal cycles differ in length, less in thickness. First or first and second septal cycles reach to the centre of the calice, later cycles are subsequently shorter. Septa of the last cycle are often attached to those of the first or second cycle. Septal distal margin unknown, lateral face occasionally with medium-sized thorns, inner margin smooth. Pali or paliform lobes absent. Some septa may be attached to the columella. Costae and synapticulae absent. Columella lamellar or formed by septal fusion. Endotheca of irregular tabulae or dissepiments. Wall compact, septothecal. Coenosteum absent. Budding extracalicinal.

Species

Sakalavastraea clementi BEAUVAIS, 1972 , Sakalavastraea collignoni ALLOITEAU, 1958 , Sakalavastraea perturbata n. sp., Glenarea poctai ELIÁŠOVÁ, 1991

Range

Callovian to Cenomanian.

Distribution

Worldwide.

Sakalavastraea clementi BEAUVAIS, 1972

Text-fig. 2

Material

BSPG-2003XX5811, 2003XX5858, 2009XVII19, 2009XVII110, CGS-HF 1701, 1704, 1710, 1712, 2339, 2402, 2405, ERNO-L 4875, MNHN-R 10752, SNSD-MMGSaKL303; 19 thin sections.

Synonymy

* v 1972 Sakalavastraea clementi nov. sp. – Beauvais, p. 96, pl. 11: 1

v 1989 Stephanastraea sp. – Löser, p. 99, text-figs 4, 5.

v 2014 ‘ Glenarea ’ sp.1 – Löser, p. 23, fig. 2g.

v 2014 ‘ Glenarea ’ sp. 2 – Löser, p. 23, fig. 2h.

Dimensions

( MNHN-R 10752)

n min–max µ s cv µ±s

cl min 35 1.83–2.68 2.24 0.27 12.2 1.97–2.52 cl max 35 2.51–3.93 3.16 0.34 11.0 2.81–3.51 ccd 60 1.93–3.49 2.61 0.38 14.7 2.23–3.00 s 10 17 –28 22.10 3.41 15.4 19–26 ( CGS-HF 2402)

n min–max µ s cv µ±s

cl min 15 1.88–2.60 2.18 0.20 9.6 1.97–2.39 cl max 15 2.32–3.48 2.84 0.30 10.6 2.54–3.14 ccd 15 2.07–3.49 2.77 0.43 15.5 2.34–3.21 s 10 18 –22 19.50 1.26 6.5 18–21 Occurrence

Lower Cretaceous (? lower Aptian) of Greece ( Viotía ) Aliartos , road cut 2 km east of Korónia. Lower Aptian of Mexico ( Michoacán ) Turitzio , Loma de San Juan ( ERNO-L4875 ). Lower Cenomanian of Greece (Kozani) Kozani, Nea Nikopolis (BSPG-2003XX5811, 5858). Upper Cenomanian , Guerangeri Zone, Korycany, Netřeba ( CGS-HF1712 ), Kopeč ( CGS-HF2402 ). Upper Cenomanian , Plenus Zone, Germany (Sachsen) Dresden-Plauen, Ratssteinbruch, southern quarry (BSPG-2009XVII110, 2009XVII19, SNSD-MMG-SaKL303) .

Sakalavastraea perturbata n. sp.

Text-fig. 3

Types

Holotype CGS-HF2478 , Paratype CGS-HF1706 .

Diagnosis

Sakalavastraea with a larger calicular diameter of 3.5– 4.5 mm, a smaller calicular diameter of 3–4 mm and 14 to 18 septa.

Comparison

The species is comparable to S. poctai but the number of septa is always far below 24. S. clementi has smaller calicular dimensions.

Derivatio nominis

(lat.) confused, in reference to the problematic taxonomic situation.

Locus typicus

Czech Republic, Central Bohemian region, Korycany, Netřeba.

Stratum typicum

Peruc-Korycany Fm., Korycany Mbr.; upper Cenomanian, Guerangeri Zone.

Material CGS-HF 1700, 1703, 1706, 2412, 2478; 12 thin sections.

Synonymy

v 1991 Glenarea cretacea POČTA, 1887 – Eliášová, p. 99, pl. 1: 1.

Dimensions

( CGS-HF 2478)

n min–max µ s cv µ±s clmin 7 2.78–4.04 3.36 0.41 12.4 2.95–3.78 cmax 7 3.42–4.60 3.93 0.47 11.9 3.46–4.40 ccd 7 2.77–5.09 3.83 0.81 21.3 3.01–4.65 s 6 14 –18 15.83 1.72 10.8 14–18

Occurrence

Upper Cenomanian, Guerangeri Zone, Czech Republic (Central Bohemian region), Korycany and Netřeba localities, and Plenus zone, Kopeč locality.

Figures

Text-fig. 2. Sakalavastraea clementi BEAUVAIS, 1972, CGS-HF2402, a, transversal thin section, b, transversal thin section, detail, c, longitudinal thin section. Scale bar 1 mm.

Text-fig. 3. Sakalavastraea perturbata n. sp., a, c, holotype and invalid neotype of Glenarea cretacea (CGS-HF2478), transversal thin section; b, d, paratype (CGS-HF1706), b, transversal thin section, d, longitudinal thin section. Scale bar 1 mm.