. Bulletin of the Natural Histort Museum. Geology series. UPPER ORDOVICIAN BRACHIOPODS FROM KAZAKHSTAN 77 cruralium median sepum. Fig. 21 Transverse serial sections of Nikolaispira guttula sp. nov., 1-3, BC 57588; 4-5, BC 57589, Sample 948, Tesik River. Distance in mm is measured from the posterior tip of ventral beak. Dorsal valve uppermost. DISCUSSION. This species was described and discussed in detail by Popov etal. (1999). Genus NIKOLAISPIRA Nikitin & Popov in Nikitin, Popov & Holmer, 1996 TYPE SPECIES. Nikolaispira rasilis Nikitin & Popov in Nikitin et al., 1996, from the Dula
. Bulletin of the Natural Histort Museum. Geology series. UPPER ORDOVICIAN BRACHIOPODS FROM KAZAKHSTAN 77 cruralium median sepum. Fig. 21 Transverse serial sections of Nikolaispira guttula sp. nov., 1-3, BC 57588; 4-5, BC 57589, Sample 948, Tesik River. Distance in mm is measured from the posterior tip of ventral beak. Dorsal valve uppermost. DISCUSSION. This species was described and discussed in detail by Popov etal. (1999). Genus NIKOLAISPIRA Nikitin & Popov in Nikitin, Popov & Holmer, 1996 TYPE SPECIES. Nikolaispira rasilis Nikitin & Popov in Nikitin et al., 1996, from the Dulankara Regional Stage (Upper Caradoc), north Betpak-Dala, Kazakhstan. Nikolaispira guttula sp. nov. PI. 14, figs 47-57; Fig. 21 ETYMOLOGY. After guttula, Latin - small drop. HOLOTYPE. BC 57585, PI. 14, figs 50-53, conjoined valves, from the Anderken Formation, Sample 2538, Kujandysai section. Material. 38 conjoined valves from Samples 100 (=K-98/1970), 626, 8221 (BC 56770, 37857-58), Anderkenyn-Akchoku section; Samples 628, 2538 (BC 57584, 85), 8257, Kujandysai Section; Sample 948 (BC 57588, 89), Tesik River. Description. Shell smooth, ventribiconvex, slightly elongate, subpentagonal in outline, about 64% as thick as long and 117% as long as wide. Anterior commissure parasulcate. Ventral valve profile strongly and evenly convex with maximum thickness near the mid- valve. Delthyrium small, open, narrow triangular. Beak slightly acuminate, erect posteriorly. Shallow ventral sulcus originating slightly posterior of the mid-valve, flanked by two low, rounded plications and terminating in a narrow, semicircular tongue. Dorsal valve gently convex with maximum thickness slightly posterior to mid-length. Median fold low and narrow, originating near mid- valve. Ventral interior with delicate teeth and short, thin dental plates placed closely to the lateral sides of the valve. Dorsal interior with small cruralium on a thin, long median septum extending anteriorly to mid-valve (Fig. 21). S
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