Nehdentomis Matern, 1929

Olempska, Ewa, 2002, The Late Devonian Upper Kellwasser Event and entomozoacean ostracods in the Holy Cross Mountains, Poland, Acta Palaeontologica Polonica 47 (2), pp. 247-266 : 261

Genus Nehdentomis Matern, 1929

Nehdentomis pseudorichterina ( Matern, 1929) .—All the specimens (Fig. 9F) from the Płucki section included in this speciesarepoorlypreserved.Thelateraloutlineofthisspecies is asymmetrically oval, the dorsal margin is slightly curved and the ventral margin is more strongly curved. The posterior end is broadly and symmetrically rounded, the anterior end is more narrowly and asymmetrically rounded. The greatest heightisintheanteriorthird.Thesurfacebears28–35longitudinalribs,thoseinthedorsalpartofthevalverunstraight,and those in the ventral part are slightly curved with some ending against the innermost dorsal rib. Four to five ribs run concentricallyandparalleltomargins.Bifurcationsofribsispresent. Thesulcusisshortandweak.Themusclepitiswelldeveloped andcircular,lyingjustinfrontofthemiddle.Aslightindentation of the anteroventral part of the margin is present.

Range and occurrence.—This species is common in the middle and late Frasnian, W. cicatricosa – E. (E.) splendens zones, and in the early Famennian of Europe ( Germany, Poland, GreatBritain, Belgium, Spain);lateFrasnianofSahara, Algeria; late Frasnian of the Volga−Ural region, Russia; late Frasnian–early Famennian of China.

Nehdentomis sp. —This poorly preserved and rare species ( Fig. 12F ) occurs in the early Famennian (samples P−152 to P−166) part of the Płucki section. The ribbing pattern with longitudinalribsinthemiddlepartofthevalveandparallelto the posterior end somewhat resembles those of N. pseudorichterina .

Figures

Fig.12. A–E. Franklinella (Franklinella) sigmoidale Müller−Steffen,1964. A.CarapaceZPALO.52/12inrightlateralview;sampleP−152. B.CarapaceZPAL O.52/1 in left lateral view; sample P−157. C. Left valve ZPALO.52/13 in lateral view; sample P−152. D. Right valve ZPALO.52/2 in lateral view; sample P−157.E.LeftvalveZPALO.52/78inobliqueventralview.F. Nehdentomis sp.CarapaceZPALO.52/22inleftlateralview;sampleP−166.Scalebars500µm.