Hadyrhyncha sp.

Halamski, Adam T. & Baliński, Andrzej, 2009, Latest Famennian brachiopods from Kowala, Holy Cross Mountains, Poland, Acta Palaeontologica Polonica 54 (2), pp. 289-306 : 299

Hadyrhyncha sp.

Fig. 6E .

Material.—A single articulated shell, most probably from set L, ZPAL Bp 57/115.

Description.—Shell ovate, 27.3 mm wide, 18.5 mm long, and 9.5 mm thick, distinctly transverse (length to width ratio 0.68), moderately ventribiconvex. Maximal width slightly anteriorly to midlength, maximal thickness in the posterior region. Umbo fine, incurved at ca. 45 ° in relation to the commissural plane. Dorsal valve with a broad (16.8 mm at anterior commissure or 0.62 of the total width), flat−bottomed sulcus appearing at 1/3 of the valve length. Ventral fold very low, flat, apparent only in the anterior region. Anterior commissure unisulcate, deflection broad and low. Ornamentation of low, rounded costae, three dorsal ones appearing at ca. 1/3 of the valve length and four ventral ones appearing at ca. 1/5 of the valve length.

Remarks.—This form is included into Hadyrhyncha on account of its transverse outline, inverse sulcation, and weak, rounded costae. It differs from the two species described within this genus, namely H. hadyensis Havlíček, 1979 from the Famennian (UD−V to UD−VI) of Moravia and H. meridionalis Sartenaer, 1998 from the Famennian (UD−V) of Morocco in possessing broader costae, and from the former moreover in having a higher deflection of the anterior commissure ( Sartenaer 1998a). Consequently, it represents a new species within the genus Hadyrhyncha , which is not named because of lack of sufficient material.

Figures

Fig. 6. Transverse serial sections of Novaplatirostrum sauerlandense Sartenaer, 1997 through shell ZPAL Bp 57/40 from Kowala, set L. Numbers indicate distances in mm from ventral umbo.