Praeschuleridea sp. 1

Wannenmacher, Norbert, Dietze, Volker, Franz, Matthias & Schweigert, Guenter, 2021, New records of ostracods and ammonites from the Aalenian (mainly Concavum Zone) of the Zollernalb (Swabian Alb, SW Germany), Zitteliana 95, pp. 1-55 : 12

Praeschuleridea sp. 1

Fig. 11: 15-17

Material.

4 C, 2 RV, 4 LV in samples He19-27 and Ha19-5.

Occurrence.

Upper Aalenian, Concavum Zone to Early Bajocian; SW Germany.

Description.

Medium-sized, subovate. Left valve larger than right valve, overlapping along complete outline. Anterior margin slightly asymmetrically rounded, extremity just below mid-height. Posterior margin triangular, upper margin straight, lower margin convex, the two joining at an angle below mid-height. Dorsal margin convex, ventral margin convex with slight concavity in front of mid-length in the right valve. Anterior cardinal angle rounded, posterior cardinal angle sloping straight to the posterior margin. Valve ventrolaterally swollen. Small-sized pits irregularly distributed over the anterior valve surface, significantly denser in the posterior third. A narrow channel with densely arranged pits parallels the anterior margin. Anteroventrally and posteroventrally there is a row of finest denticles.

The partly broken (? paleohemimerodont) hinge shows terminal serrated teeth and remains of teeth in the median hinge area of the right valve.

Figures

Figure 11. (1) Balowella catena (Franz et al.), SMNS 70521 / 80, C, right view, L: 0.329 mm; sample He 19 - 18. (2, 3);? Cytheropteron sp. 1, (2) SMNS 70521 / 81, LV, L: 0.322 mm; sample He 19 - 27; (3) SMNS 70521 / 82, RV, L: 0.355 mm; sample He 19 - 27. (4, 5) Procytheropteron aff. gramanni Brand, (4) SMNS 70521 / 83, LV, L: 0.373 mm; sample He 19 - 26; (5) SMNS 70521 / 84, RV, L: 0.305 mm; sample He 19 - 22. (6) Procytheropteron sp. 1 Franz et al., SMNS 70423 / 66, LV, L: 0.322 mm; sample G 20 b; (7) Aphelocythere recta Ohmert, SMNS 70521 / 85, C, right view, L: 0.460 mm; sample Ro 19 - 4. (8) Aphelocythere aff. recta, SMNS 70521 / 86, C, right view, L: 0.466 mm; sample Ro 19 - 4. (9) Aphelocythere sp. 1, SMNS 70521 / 87, RV, L: 0.630 mm; sample He 19 - 27; (10) " Asciocythere " sp., SMNS 70521 / 88, RV, L: 436 mm; sample He 19 - 26. (11) Eocytheridea elongata Bate, SMNS 70521 / 89, RV, L: 0.573 mm; sample He 19 - 21. (12) Eocytheridea lacunosa Bate, SMNS 70521 / 90, RV, L: 0.705 mm; sample He 19 - 25; (13, 14) Praeschuleridea cf. subtrigona, (13) SMNS 70521 / 91, C, right view, L: 0.512 mm; sample Ro 19 - 5; (14) SMNS 70521 / 92, RV, inner view, L: 0.512 mm; sample Ro 19 - 5; (15 - 17) Praeschuleridea sp. 1, (15) SMNS 70521 / 93, C, right view, L: 0.490 mm; sample He 19 - 27, (16) SMNS 70521 / 93, C, right view, (detail); (17) SMNS 70521 / 94, RV, L: 0.620 mm; L: 0.620 mm; sample He 19 - 27. (18) Pleurocythere ohmerti Franz et al., SMNS 70521 / 94, LV, L: 0.479 mm; sample Tst. 38 - 1988 (= He 19 - 27). Achdorf Formation, Upper Aalenian, (1, 6) Bradfordensis Zone (Gigantea Subzone), (2 - 5, 7 - 18) Concavum Zone. Scale bars (if not indicated otherwise): 20 μm.