Asteroseris Fromentel, 1867

Löser, Hannes & Főzy, István, 2015, Asteroseris from the Bersek Marl (Gerecse Mountains, Hungary; Early Cretaceous; Anthozoa), Fragmenta Palaeontologica Hungarica 32, pp. 3-10 : 7-8

Genus Asteroseris Fromentel, 1867

Type species – Stephanoseris coronula Fromentel, 1863 by monotypy.

Asteroseris is a small solitary patellate coral with a circular outline. The septa are compact. The microstructure of the septa is unknown. They are in cross section externally slightly thicker, and slightly thinner towards the centre, with a maximum thickness of 250 Μm. The symmetry of the septa is radial and regularly hexameral, with regular cycles. The cycles differ in length, but almost not in thickness. The septa of the first cycle extend to the centre of the calice; later cycles are shorter. The septa of younger cycles are often and regularly connected to the septa of preceding cycles. The septal upper margin is unknown. The lateral septal face occasionally shows small thorns; the inner margin is unknown. Pali or paliform lobes are absent. All septa of the first cycle are attached to the columella. The costae are unknown. Synapticulae are present. The columella is formed by septal fusion in the centre of the calice. Endotheca and the wall are unknown.

Asteroseris was originally indicated in the Cenomanian of Le Mans ( France), later in the Early Albian of France and Iran, and the Early Aptian of Greece. Apart from the type species, two questionable Late Cretaceous species are known that probably do not belong to this genus (see LÖSER 2013 for more details) .

Asteroseris sp.

( Fig. 3 )

Description – Small solitary cupolate coral with a diameter of 10–15 mm

(rarely up to 18 mm) and a height of about 3–6 mm. The septa are thick, compact and in a regular hexameral symmetry. Twenty-four septa reach the centre of the calice. The remaining 24 septa are shorter and connected to 12 large septa. Synapticulae are common, but not so regular as in the type species. The endotheca is absent. The wall and centre of the calice are unknown. The outer surface of the wall (= bottom of the coral) is wrinkled and shows concentric growth lines.

Remarks – The material differs from the type species by a higher calicular diameter. There are no other species: A. vidali Reig Oriol, 1989 and A. formosus Reig Oriol, 1995 are too poorly preserved to assign them to any genus; Funginella isfahanensis Yazdi et al. 2011 is a junior synonym of the type species.

Occurrence – The coral was found throughout the whole section C (bed numbers 204, 211, 225, 226, 228, 233–36, 239–43, 251–52, 255) encompassing the interval from the Late Valanginian (Peregrinus Zone) to the top of the Hauterivian.

Figures

Fig. 3. Asteroseris sp. Transversal thin section. Specimen INV 2015.3. (Hungarian Natural History Museum, Budapest)