Praewaagenoconcha Sokolskaya, 1948

Baliński, Andrzej, 2002, Frasnian-Famennian brachiopod extinction and recovery in southern Poland, Acta Palaeontologica Polonica 47 (2), pp. 289-305 : 294

Genus Praewaagenoconcha Sokolskaya, 1948 Praewaagenoconcha cf. speciosa ( Hall, 1867)

Fig. 3B–D .

Praewaagenoconcha cf. speciosa ( Hall, 1867) ; Baliński 1979: 31–32,

pl. 3: 3, 6.

Material.—31 fragmentary specimens from trench Z−17. This species is rare in the most of the trench Z−17 section although it is quite common in the upper part of the set II being one of the characteristic brachiopods of the assemblage of the Pampoecilorhynchus geniculatus interval.

Remarks.— Three specimens of the species reported in earlier studies were recovered from slightly younger strata of trench Z−16 and quarry Z−2 from the lower part of Pa. triangularis conodont Zone ( Baliński 1979). The present collection, although rather poorly preserved, includes numerous specimens. This species is closely similar to Productella speciosa Hall from the Chemung Group, USA ( Hall and Clarke 1892: pl. 17: 25, 26) in its general appearance. It has relatively fine spines, which occur on both valves. One specimen preserves ventral teeth and dorsal sockets. Aspine bearing median ridge, a feature common to members of Praewaagenoconcha , is not observed on the ventral valves of available specimens.

Figures

Fig. 3. Early Famennian brachiopods, trench Z−17, Dębnik anticline, Poland. A. Barroisella campbelli Cooper, 1942; partially exfoliated shell Bp 46/48a in dorsal view; × 3. B–D. Praewaaagenoconcha cf. speciosa (Hall, 1867). B. Exterior of the ventral valve Bp 46/20a. C, D. Internal view of two partially exfoliated dorsal valves Bp 46/25a and Bp 46/25b; × 1.5. E–G. Nigerinoplica sp. E, F. Side view of two shells Bp 46/24a and Bp 46/18a. G. Shell Bp 46/24b in dorsal view showing partially removed ventral valve and interior of the dorsal valve; × 1.5. H. Schizophoria (Schizophoria) sp.; incomplete shell Bp 46/37a in dorsal view; × 1.5. I. Rhipidomellid gen. et sp. indet; exterior of poorly preserved ventral valve Bp 46/40; × 2. J.?Ryssochonetes sp.; incomplete shell Bp 46/15 in ventral view; × 15. K. Longispina sp.; poorly preserved shell Bp 46/17z in ventral view; × 5.