Kilka ważniejszych nowych gatunków otwornic małżoraczków z osadów triasu Polski

Olga Styk




Short characteristics of some species of foraminifers and ostracods from the Triassic deposits of the Lowland area of Poland are given. Table 1 presents the vertical distribution of stratigraphically more important species.

The deposits of Triassic age in the Extra-Carpaithian area of Poland are developed mainly as clay-sand, carbonate-day and clay-siltstone deposits (H. Senkowiczowawa, A. Szyperko-Śliwczyńska, 1961).
The Triassic deposits reveal both genera and species of foraminifers and ostracods that occur in the boreal province (Lower Triassic), and those of the Alpine zone of the European Triassic (particularly Middle Triassic).
Within the area of the Polish Lowland are found foraminifers of the family Nodosariidae, as well as few representatives of the families Spirillinidae, Nubeculariidae, Polymorphinidae, Lituolidae, Ammodiscidae and Astrorhizidae.
Among the ostracods there occur both marine – mainly in the deposits of the Middle Triassic – and brackish-marine representatives of this animal group. To the more important genera which characterize the individual members of the Triassic belong: Darwinula, Lutkevichinella, Clinocypris, Cytherissinella, Pulviella, Glorianella, Spelncella, Bairdia, Hungarella, Judahella, Monoceratina, Cytherella, Paracypris, Gemmanella, Rhombocythere and Klieana ?


Trochamminoides antis n. sp.
                  (Table I, Figs. 1–3)

Test small, planispiral, partly involute, consisting of 2–2,5 whorls. In the last whorl – 8–9 chambers. Chambers fine, slightly incised, 13–14 in number. Initial chamber small, round, next chambers irregular in shape and dimension, increase with the growth. Test surface smooth, test wall finely arenaceous with calcareous cement. Occurrence: Upper Muschelkalk.

Orthovertella? flexuosa n. sp.
                 (Table I, Figs. 4–7)

Test small, calcareous, consisting of a small oval initial chamber and of second tubular chamber which, in its initial pad, is involuted spirally, and then passes in a straight part. At cross section 2,5 whorls can be observed occurrence: Upper Muschelkalk.

Ophthalmidium granum n. sp.

(Table I, Figs. 8, 9)

Calcareous test smooth, chamhers almost invisible. Initial chamber round, second chamber tubular, slightly widened at the base, making 1/2 whorl. Third chamber more widened at the base, equal to 1/2 whorl in length. The next two, three chambers, 1/2 whorl in length each, are arranged alternately on both sides of the long axis of the test. Occurrence: Upper Muschelkalk.

Lenticulina (Astacolus) dobroviensis n. sp.
                             (Table I, Fig. 10)

Calcareous test transparent, small, in leaf-like shape, consisting of four chambers. Initial chamber oval, placed transversely, next chambers triangular. The last chamber strongly convex on the ventral side, covering the entire ventral side, and at its base adjoins the initial chamber. Deep sutures rest arcuately on septa. Occurrence: Upper Muschelkalk.

Pachyphloides? triangularis n. sp.
                (Table I, Figs. 11, 12)

Test small, smooth, uniserial. In the initial part narrow, widening regularly upwards to obtain the final part 3–4 times greater width than in its initial part 8–9 chambers. Chamber initially round, the next chambers low, arcuate and saddle-shaped, slightly embracing each other. Sutures a little saddle-shaped. Occurrence: Upper Muschelkalk.

Dentalina gerkei n. sp.
                 (Table I, Fig. 13)

Test small, elongated, slightly arcuately curved, consisting of 7–8 chambers arranged uniserially. Initial chamber slightly elongated, acutely terminated. The next chambers more convex, increase and take oval shape. The last chamber 2–3 times wider than the initial one. Occurrence: Upper Muschelkalk.

Ramulina subcylindrica n. sp.
                  (Table I, Figs. 14–16)

Calcareous test, free, chambers oval more or less elongated, connected by means of tubes arranged rather unsymmetrically on both sides of the chambers. Occurrence: Upper Muschelkalk.

Spirillina oberhauseri n. sp.
               (Table I, Figs. 17, 18)

Test small, planitspiral, consisting of a small initial chamber and of the second tubular chamber that makes 5–7 whorls. The last whorl is the widest one, separated by a slightly sunk suture. Occurrence: Upper Muschelkalk.


Bairdia sohni n. sp.
           (Table II, Figs. 4a, b, 5)

Shell small, margin in the central part arcuately curved, passes in a wider, more rounded anterior end and sharp posterior end. Ventral margin almost straight or concave in the central part of the shell. Shell surface covered with fine pores. Occurrence: Upper Muschelkalk.

Clinocypris? silesia n. sp.
               (Table II, Fig. 3a, b)

Shell in the shape of an oval triangle. Dorsal margin rounded and inclined towards anterior end. Posterior end considerably lower than the anterior one. The latter widely rounded and slightly cut in the vicinity of ventral margin, which is a little can cave in the posterior part of the shell. Surface smooth. Occurrence: Lower Rhaetic.

Darwinula? wandae n. sp.
             (Table II, Figs. 6–8a, b)

Shell pear-shaped, dorsal margin arcuately curved, ventral margin concave in the central part of the shell. In the posterior part the shell strongly convex. Shell surface smooth or covered with very fine pores. Occurrence: Lower Rhaetic.

Darwinula gołdapi n. sp.
             (Table II, Figs. 1, 2a, b)

Shell oval; dorsal margin arcuately curved in the posterior part, gradually passing into a slightly rounded one, slightly inclined forward; anterior end considerably lower. Ventral margin almost straight. Shell surface smooth. Occurrence: Lower Buntsandstein.

Monoceratina? exiqua n. sp.
           (Table III, Figs. 3a, b, 4a, b, 5a-c)

Shell small, almost rectangular. Dorsal margin straight, ventral margin also straight, almost parallel to the dorsal margin. Lateral surfaces of shell covered with pores, a sulcus occurring in the central part of the shell. At ventral margin a cylindrical swelling occurs. A nodule is found in the anterior part of the shell, and a sulcus runs through its central part. Occurrence: Upper Muschelkalk.

Monoceratina kozuri n. sp.
                               (Table III, Fig. la, b)

Shell almost rectangular in shape. Dorsal margin straight, ventral margin straight, parallel to the dorsal margin. A spine is found on the lateral area near the ventral margin. In the anterior part of the shell a nodule occurs; another nodule, considerably smaller can be found in the anterior dorsal part of the shell. A transverse sulcus intersects the central part. Occurrence: Muschelkalk.

Monoceratina paula n. sp.
                              (Table III, Fig. 2a-c)

Shell rectangular in shape, dorsal margin straight, ventral margin straight, parallel to the dorsal margin. Shell surface covered with fine pores. In the centre of the shell a distinct tansverse sulcus occurs. In the central part of the lateral area a round nodule occurs. At the ventral margin a rib begins, which terminates in the posterior part of the shell with an acute end. Occurrence: Upper Muschelkalk.

Rhombocythere gorzoviensis n. sp.
                                (Table III, Figs 6a-d, 7, 8)

Shell romboidal in shape. Dorsal margin straight, passing in a rounded anterior end, and in a slightly truncated posterior end. Ventral margin straight. Lateral areas of the shell covered with pores. On the lateral area, at the ventral margin a ridge occurs. On the ventral side there are found 10–11 elongated fine ribs. Occurrence: Lower Rhaetic.
                        Lutkevichinella mazurensis n. sp.
                             (Table II, Figs. 9a b, 10–12)

Shell oval-rectangular. Dorsal margin straight passing into a widely :rounded anterior end, where it makes anangle like in the posterior dorsal part. The posterior end slightly lower than the anterior one. A small sulcus runs in the central part. Along the ventral margin a short ridge runs. Surface smooth or covered with very fine pores. Occurrence: Lower Buntsandstein.


              Hungarella gemma n. sp.
              (Table III, Figs. 9a, b, l0a, b)


Shell oval with strongly convex lateral areas. Dorsal margin convex, ventral margin straight or slightly concave in the central part of the shell. Lateral areas of the shell covered with very fine pores. Occurrence: Roethian.


             Hungarella semirotundata n. sp.
                  (Table III, Fig. 11)


Shell semicircular. Dorsal margin of the right shell more arcuately curved than that of the left shell. Central part of dorsal margin of the right shell turned inside out cylindrical swelling. Shell surface smooth or covered with very fine pores. Occurrence: Lower Muschelkalk.

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