Sinodisphyllum variable Sun, 1958, 2002

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 : 382

Sinodisphyllum variable Sun, 1958

Fig. 8E–G, I .

Sinodisphyllum variable n. sp.; Sun 1958: 12, pl. 4: 1, 2, pl. 5: 1, pl. 6: 1. Material.— Eight specimens.

Remarks.—Our specimens are conico−cylindrical in form. The number of septa increases with diameter, from 27 majors at a diameter of 13.5 mm to 34 at a diameter of 23–29 mm. The outer zone of the septum is weakly to moderately dilated, forming or without forming an inner wall at the inner margin of the dissepimentarium. The majors are long, becoming thin in the inner zone; the minor septa are very short, only 1/5 length of the majors. The dissepimentarium is wide; the dissepiments are mainly concentric, commonly with a few rows of dense herringbone dissepiments near the inner margin of the dissepimentarium, in which case the tabularium is generally divided into three distinct parts. In longitudinal section, variously sized dissepiments are arranged in 5 to 7 rows. Tabulae are incomplete, 1/2 diameter wide; the axial series of tabellae are sometimes cystose, in which case the dissepiments are generally concentric in cross section.

Specimens of S. simplex Sun, 1958 are characterized by scolecoid form, smaller diameter, more septa, complete tabulae ( Fig. 8H ), and mainly herringbone−shaped dissepiments. These specimens co−occur with S. variable .

Occurrence.— Central Hunan Province in Xiangxiang County and at the Xikuangshan and Chongshanpu sections; Frasnian .

Figures

Fig. 8. Latest Frasnian (upper part of the Pa. linguiformis Zone) rugose corals from central Hunan.A, B. Peneckiella shawoziensis He, 1978. Transverse and longitudinal sections, specimen PUM 93595, sample L5/top0.2 (upper 20 cm of bed L5; × 6). C, D. Temnophyllum sp. Longitudinal and transverse sections, PUM 93594, sample L5/top0.2; × 4. E–G, I. Sinodisphyllum variable Sun, 1958. E, F. Transverse and longitudinal sections, PUM 93600, bed T3 of the Chongshanpu section; × 2.3. G. Transverse section, PUM 00072, bed T3, × 2.3. I. Longitudinal section, PUM 93596, sample L5/top0.2, × 2.3. H. Sinodisphyllum simplex Sun, 1958. Longitudinal section, PUM 93601, bed T3, × 2.3. J, K. Sinodisphyllum litvinovitshae (Soshkina, 1949) from the top of the Frasnian of Taotang, about 2 km north of the Xikuangshan section. J. Longitudinal section, PUM 00073, × 2.3. K. Transverse section, PUM 93599, × 2.3. L. Disphyllum dupliforme Kong, 1978, longitudinal section, PUM 93592, same specimen as Fig. 7H, × 4.