28 



LPw length and width of lophophore platform; X - mean; S - 

 standard deviation from the mean; r- coefficient of correlation; OR 



- observed range; max. - maximum value; min. - minimum value; N 



- number of measured or counted specimens. 



L.E. POPOV, L.R.M. COCKS AND I.F. NIK1TIN 



species, which makes precise comparison difficult. The main differ- 

 ence of the Kazakh species from the latter is the less elongate shell 

 outline, which is no more than twice as long as wide. A detailed 

 description, discussion and the basic statistics of this species was 

 provided by Popov ( 1980). 





Order LINGULIDA Waagen, 1885 

 Superfamily LINGULOIDEA Menke, 1828 



Family OBOLIDAE King, 1846 



Subfamily GLOSSELLINAE Cooper, 1956 



Genus ECTENOGLOSSA Sinclair, 1945 



Type species. Lingula lesueueri Rouault, 1850, from the Arenig 

 of Normandy, France. 



Ectenoglossa sorbulakensis Popov, 1980 PI. 1, figs 1^1 



1980 Ectenoglossa sorbulakensis Popov: 142, pi. 1, figs 1-4. 

 1984 Ectenoglossa sorbulakensis Popov; Nikitin & Popov in 

 Kleninaera/.: 142, pi. l,figs 1^1. 



Holotype. CNIGR 1/11523, ventral internal mould, from the 

 Anderken Formation, locality 1024, east side of Karatal valley. 



Material. Six pairs of conjoined valves, 26 ventral and 3 1 dorsal 

 valves from Sample 8130a, Anderkenyn-Akchoku; Samples 8227- 

 10, 8227^40 (BC 57370-73), 8227-80, Buldukbai Akchoku; 8228a, 

 east side of Kopalysai; all Chu-Ili Range; Sample 1024, east side of 

 Karatal Valley, south Betpak-Dala. 



Description. Shell equivalved, elongate, subrectangular in out- 

 line, about 1 90% as long as wide with maximum width at mid-length, 

 ornamented by fine concentric fila about 13-15 per mm. Ventral 

 valve very gently convex with narrow, triangular pseudointerarea, 

 mainly occupied by deep pedicle groove and small propareas crossed 

 by flexure lines. Dorsal valve gently convex, lacking pseudointerarea. 

 Ventral interior with pair of slightly diverging, elongate, suboval 

 umbonal muscle scars flanked laterally by pair of short diverging 

 ridges; pedicle nerve impression well defined. Dorsal interior with 

 weak median ridge. 



Discussion. Ectenoglossa sorbulakensis closely resembles 

 Ectenoglossa minor Zhan & Cocks (1998: 14) from the Lower 

 Ashgill of South China in having a strongly elongate equivalved 

 shell with subparallel lateral margins, rudimentary ventral 

 pseudointerarea and propareas with well defined flexure lines. How- 

 ever, the interiors of both valves are weakly impressed in the Chinese 



Superfamily DISCINOIDEA Gray. 1840 



Family TREMATIDAE Schuchert, 1893 



Genus TREMATIS Sharpe, 1848 



TYPE SPECIES. Orbicula terminalis Emmons, from the Trenton 

 Group (Caradoc), New York, U.S.A. 



Trematisl sp 



PI. 1, figs 5, 6 



Material. Figured dorsal valve, BC 57375 (L=14.8, W=14.4) 

 and another dorsal valve, Samples 127, 8228, Kopalysai. 



DESCRIPTION. Shell subcircular, ornamented by radial capillae of 

 about 5 per 1 mm enlarged in number by intercalation and with 

 radially arranged rounded or transversely suboval pits in the 

 interspaces between capillae. Ventral valve unknown. Dorsal valve 

 gently and unevenly convex in transverse profile with maximum 

 height about one-third of the valve length from the marginal umbo. 

 Dorsal interior unknown. 



Discussion. These specimens are similar to the shells described 

 by Cooper (1956: 275) as Trematis sp. 3 from the Cyrtonotella Zone 

 of the Edinburg Formation (Caradoc) of Virginia in their pits and 

 radial ornament. The ventral valve in both unnamed species remains 

 unknown, and therefore the generic attribution is provisional. 



Family DISCINIDAE Gray, 1840 



Subfamily ORBICULOIDEINAE Schuchert, 1929 



Genus SCHIZOTRETA Kutorga, 1848 



Type SPECIES. Orbicula elliptica Kutorga, presumably Volkhov or 

 Kunda Stage (Upper Arenig-Lower Llanvirn), vicinity of St. 

 Petersburg. Russia. 



Schizotreta sp. 



PI. 1, figs 7-10 



Material. One pair of conjoined valves, one ventral and two 

 dorsal valves from Samples 100 (BC 57590) and 626, Anderkenyn- 

 Akchoku section; Samples 628 (BC 56825), 2538, Kujandysai section 



PLATE 1 



Figs 1-4 Ectenoglossa sorbulakensis Popov. Sample 8227—40, Buldukbai-Akchoku section, west side of Kopalysai. 1, BC 57370, ventral exterior, x 2. 2, 



BC 57372, dorsal internal mould, x 2. 3, BC 57371, dorsal exterior, x 2. 4, BC57373, ventral internal mould, x 2. 

 Figs 5, 6 Trematis ? sp. Sample 8228, east side of Kopalysai, BC 57375, dorsal exterior and surface ornament, x 6, x 2. 



Figs 7-10 Schizotreta sp. Sample 100, Anderkenyn-Akchoku section, BC 57590, conjoined valves, posterior, dorsal, lateral and ventral views, x 2. 

 Fig. 11, 12 MesotretaP. sp. Sample 100, Akchoku Mountain, Anderkenyn-Akchoku section, CNIGR 1/12361, ventral exterior and lateral view, x 8. 

 Figs 13, 14 Nushbiella dubia Popov. Sample 2538, Akchoku Mountain, Kujandysai section. BC 57591 ; 13, dorsal exterior, x 8; 14, ventral exterior, x 8. 

 Fig. 15 Paracraniops sp. Sample 8128a, Anderkenyn-Akchoku section, BC 57377, dorsal internal mould, x 5. 

 Figs 16-21 Longvillia lanx (Popov), Sample 1018, area 7 km southwest of Karpkuduk well, Kotnak mountains, south Betpak-Dala. 16, 17. CNIGR 27/ 



1 1989, latex cast of cardinalia and dorsal interior, x 5, x 2. 18-20, CNIGR 27/11989, dorsal, ventral and lateral views of conjoined valves, x 1. 21, 



CNIGR 30/1 1989, holotype, ventral internal mould, x 2. 

 Figs 22-28 Bellimurina (Bellimurina) sarytumensis sp. nov. 22, 23, Sample 8214, BC 57379, holotype, Anderkenyn-Akchoku section, ventral exterior 



and lateral view, x 2. 24, 25. Sample 2538, Akchoku Mountain. Kujandysai section, BC 57378, conjoined valves, dorsal and ventral views, x 3. 26, 



Sample 1041a, Burultas Valley, BC 57364, dorsal internal mould, x 2. 27, Sample 100, Anderkenyn-Akchoku section, BC 57380, ventral exterior, x 3. 28, 



Sample 2538, CNIGR 10/12361, dorsal external mould, x 3. 

 Fig. 29 Dolerorthis expressa Popov. Sample 1018, 7 km southwest of Karpkuduk well, Kotnak Mountains, BC 57368, ventral internal mould, x 1.5. 

 Figs 30, 31 Furcitellinae gen. et sp. indet. Sample 628, west side of Kujandysai, BC 57381, ventral and dorsal views of conjoined valves, x 1.5. 



