Stylophyllopsis silingensis ( Liao, 1982)

Stylophyllopsis silingensis ( Liao, 1982)

Fig. 9L View Fig , Figs. 10F–H, J View Fig

*1982 Donacosmilia silingensis Liao (sp. nov.): Liao, p. 166, Pl. 14, Figs. 1–2 View Fig View Fig .

1994 Donacosmilia silingensis Liao : Liao & Xia, p. 78, Pl. 8, Figs. 5–6 View Fig View Fig .

Dimensions. Great diameter of corallites: 6–11 mm; small diameter of corallites: 5–7 mm; septa/corallite: 32 to around 46.

Description. Phaceloid colony; corallites subcircular to elongate in outline; septa generally straight, arranged bilaterally in 4 to 5 size orders, irregularly alternating in length and thickness; up to around 20 septa reach corallite center; columella weakly developed.

Type locality of species. Hauterivian of Tibet (Xainza County; Toiba Formation) .

Distribution. Lower Valanginian of northeastern Switzerland (Vitznau Marl, Wart; this paper), Hauterivian of Tibet.

Material. NMSG Coll. PK–02.10.23c (= 02.10.29c); –02.10.25b; –02.10.35c (= 02.10.35f and 35f-II); –02.10.35d (= 02.10.35g); –02.10.35e (= 02.10.35h); –02.10.35l.

Remarks. Study of the lectotype of the type species of Stylophyllopsis Frech ( S. polyactis [SNSB-BSPG-AS- XII-53]) in 2020 by one of the authors (RBS) revealed that, in addition to previously reported skeletal features, it also shows a peripheral, large-vesicular dissepimentarium in some places.

In having (1) septa made of spines that are connected or dissociated; (2) large and vesicular dissepiments in the peripheral area of the corallite; (3) an epithecal sensu lato wall; (4) axial ends of septa that dissociate, forming septal spines; (5) a columella formed by isolated septal spines; and (6) lamellae that occur in some of the septal spines, the material described as Donacosmilia silingensis from the Hauterivian of Tibet closely corresponds to the genus Stylophyllopsis . Te Swiss specimens show very close resemblance to the Tibetan type material as presented in Liao (1982) and Liao and Xia (1994).