Astraeomorpha confusa ( Winkler, 1861 )

Vasseur, Raphaël & Lathuilière, Bernard, 2021, Pliensbachian corals from the Western Tethys, Geodiversitas 43 (22), pp. 1187-1291 : 1198

Astraeomorpha confusa ( Winkler, 1861)

( Fig. 5 )

Thamnastraea confusa Winkler, 1861: 488 , pl. 8, fig. 10.

Astraeomorpha confusa – Roniewicz 1989: 96 pl. 28, fig. 1-2, pl. 29, fig. 1-3, cum syn. — Vasseur 2018: 131-132, fig. 3.11.

TYPE MATERIAL. — Holotype BSP AS XII 133 ( Winkler 1861: pl. 8, fig. 10). TYPE HORIZON. — Upper Rhaetian, Kössen Beds. TYPE LOCALITY. — Kothalp ( Austria). STUDIED SAMPLE. — CPUN AM16165-1.

GEOGRAPHIC AND STRATIGRAPHIC RANGES. — Norian / Rhaetian of the Alps, Caucasus, Austria, North America, Central Asia, Timor; Pliensbachian of Amellagou (High Atlas of Morocco).

DESCRIPTION

Thamnasterioid, ramose colony made up of small calices with poorly defined boundaries. Septa are generally straight, free or joined, sometimes linked to the columella, with pennular lateral faces showing meniana. Paliform structures sometimes appear at the inner edge of septa, particularly when two adjacent septa join. Microstructure unknown because of recrystallization. Styliform columella. Thick synapticulae.

Calicular diameter:approximately 1 mm – Distance between calicularcenters: 0.8 to 1.4 mm – Number of septa: 11 to 15 – Vertical density of meniana: 4 to 5 per 1 mm.

SIMILARITIES AND DIFFERENCES

Resembles A. crassisepta but, according to Roniewicz (1989), meniana are vertically more densely packed, calices are smaller and septa are thinner in the taxon herein. A case of intraspecific variability is not excluded.

Figures

FIG. 5. — Astraeomorpha confusa (Winkler, 1861): A, distal view of the specimen CPUN AM16165-1; B, detail in transverse thin section of some calices of the specimen CPUN AM16165-1; C, detail in longitudinal natural section of the pennular ornamentation of septa of the specimen CPUN AM16165- 1; D, thin section transverse to the calices and longitudinal superficial to one of the branches of the specimen CPUN AM16165-1. Scale bars: A, 1 cm; B, C, 1 mm; D, 4 mm.