Montlivaltia subcaryophyllata Alloiteau, 1957

Vasseur, Raphaël & Lathuilière, Bernard, 2021, Pliensbachian corals from the Western Tethys, Geodiversitas 43 (22), pp. 1187-1291 : 1279

Montlivaltia subcaryophyllata Alloiteau, 1957

( Fig. 64 )

Montlivaltia subcaryophyllata Alloiteau, 1957: 93 , pl. 5, fig. 4. — Vasseur 2018: 257-258, fig. 3.62.

Epismilia ? caryophyllata Fromentel & Ferry, 1865: 54 , pl. 15, fig. 2.

TYPE MATERIAL. — Holotype MNHN.F. M03506 (Fromentel coll.), Fromentel & Ferry 1865: 54, pl. 15, fig. 2. TYPE HORIZON. — Pliensbachian . TYPE LOCALITY. — May-sur-Orne, France. STUDIED SAMPLE. — Holotype MNHN.F. M03506 . GEOGRAPHIC AND STRATIGRAPHIC RANGES. — Pliensbachian of May-sur-Orne ( Calvados , France).

DESCRIPTION

Solitary, patellate corallum. Radial elements are exsert costosepta organized in 3 distinct size orders and apparently 5 distinct ontogenetic cycles (6+6+12+24+48 septa). They are straight, free, of montlivaltid structure. Endotheca made of rare peripheral dissepiments. An epitheca s.l. wraps the basis of the corallum.

Calicular diameter: 14.4 mm – Number of septa: 96 by extrapolation – Septal density: 5 per 2 mm.

SIMILARITIES AND DIFFERENCES

The differences with Montlivaltia sp. described from Moroccan Toarcian ( Vasseur 2018) is difficult to confirm because of the great intraspecific variability of the latter species and the uniqueness of the Pliensbachian specimen from Calvados. However, the specimen described herein shows quite higher septal densities and a more regular septal apparatus than the specimens from the Toarcian.

Figures

FIG. 64. — Montlivaltia subcaryophyllata Alloiteau, 1957: A, distal view of the holotype MNHN.F.M03506; B, lateral view of the holotype MNHN.F.M03506; C, detail of the montlivaltid structure of one septum in distal view of the holotype MNHN.F.M03506; D, detail of the costal part of costosepta of the holotype MNHN.F.M03506. Scale bars: A, B, 5 mm; C, 1 mm; D, 2 mm.