Frechastraea Scrutton, 1968

Ma, Xue-Ping, Sun, Yuan-Lin, Hao, Wei-Cheng & Liao, Wei-Hua, 2002, Rugose corals and brachiopods across the Frasnian- Famennian boundary in central Hunan, South China, Acta Palaeontologica Polonica 47 (2), pp. 373-396 : 380-381

Genus Frechastraea Scrutton, 1968 Frechastraea ? hsikuangshanensis Ma, 1994

Fig. 7C, I .

Frechastrea ? hsikuangshanensis n. sp.; Ma 1994: 199, pl. 45: 1–3. Material.— Four specimens.

Remarks. —This is an astreoid−aphroid form characterized by the absence of horse−shoe dissepiments, large corallites united by dissepiments, and major septa only slightly entering the tabularium. Coralla are circular or oval in outline. The boundary between neighboring corallites is generally not readily defined. Individual calicular pits, where observable, are often fairly deep, with a diameter of 5–6 mm and their centers being spaced 12–15 mm apart. Major septa are 12–14 in number and commonly dilated, showing a granular structure as feeble carinae. Tabularia are generally 5 mm in diameter, with about 3 tabellae per millimeter. The present species may be distinguished from Frechastraea dushanensis Kong, 1978 , and F. guizhouensis Kong, 1978 of the Frasnian Wangchengpo Formation of Guizhou Province, China by its large size, about two times the size of the two Guizhou species.

Occurrence.— Central Hunan Province at the Xikuangshan area ; latest Frasnian .

Figures

Fig. 7. Latest Frasnian (upper part of the Pa. linguiformis Zone) rugose corals from central Hunan. A, B. Disphyllum cf. cylindricum Sun, 1955, longitudinal and transverse sections, PUM 93593, sample L5/0.3−0.4; A × 3.8, B × 3.2. C, I. Frechastraea? hsikuangshanensis Ma, 1994., sample L5/0.85, longitudinal (× 3.6) and transverse (× 2.65) sections of the holotype specimen, PUM 93602. D, E. Phillipsastrea nevadensis Stumm, 1940, transverse and longitudinal sections of specimen PUM 93606, bed T3 of the Chongshanpu Section (see Ma 1998 for stratigraphy); × 5.5. F, G. Phillipsastrea sp., longitudinal and transverse sections, PUM 93606, bed T3; × 5.5. H. Disphyllum dupliforme Kong, 1978, transverse section, PUM 93592, from the top of the Frasnian of Taotang, about 2 km north of the Xikuangshan section (see Fig. 8L for longitudinal section); × 2.3.