Parvicingula papulata Kozlova and Vishnevskaya, 2012

Vishnevskaya, Valentina S. & Kozlova, Genrietta E., 2012, Volgian and Santonian-Campanian radiolarian events of the Russian Arctic and Pacific Rim, Acta Palaeontologica Polonica 57 (4), pp. 773-790 : 787-788

Parvicingula papulata Kozlova and Vishnevskaya , sp. nov.

Fig. 6H .

1994 Parvicingula papulata Kozlova 1994b : pl. 5: 6, 8–11 (nomen nudum). 1998 Parvicingula papulata Kozlova ; Vishnevskaya 1998: 63, pl. 8: m,

n, pl. 12: i (nomen nudum).

Etymology: From Latin papula, meaning blister or a small nodule.

Type material: Holotype GIN P−1K (see Fig. 6H ); paratype VNIGRI N667/65.

Type locality: Ukhta section, Pechora Basin , Russia. Range: Lower Kimmeridgian–Lower Volgian of Mezen (borehole 234) .

Type horizon: Lower and Middle Volgian of Volga (Gorodishce) Basin.

http://dx.doi.org/10.4202/app.2011.0040

Diagnosis.—Typical Parvicingula with pyramidal shaped cephalothorax, bearing 1 well developed apical conical horn and 2 short papula shaped spines.

Description.—Test conical with five (or more?) post−abdominal segments. Cephalis and thorax together pyramidal−domed, cephalis without perforation, thorax irregularly perforated, with coarse to thorny surface. Apical horn massive, wide conical, with apical pore; spines 2, L and D short, pyramidal or papula shaped, situated at centre of cephalo−thorax. Distinct complete circumferential ridge beginning at the base of the first post−abdominal segments. Thorax and following segments approximately equal in height, with three rows of uniform hexagonal pore frames; pores circular in outer rows, circular to elliptical in middle row.

Measurements (in µm).—Total height 127–165, height of cephalis + thorax 43–46, height abdomen and following segments 23–27, test width (maximum) 74–95, cephalis width 50–63.

Remarks.—The new species differs from congeners in having papula− or nodule−shaped spines L and D.

Geographic and stratigraphic range.—Kimmeridgian– Middle Volgian of Mezen; Pechora and Volga basins, Russia.

Figures

Fig. 6. Scanning electron photomicrographs of Late Jurassic radiolarians from siliceous clay rocks in northern Russia, Barents Sea region. A–F from Kozlova (1994b). A. Quasicrolanium planocephala (Kozlova, 1976), uppermost Volgian, Kolguev offshore, borehole 140, sample 140, VNIGRI N 140−667/41a. B–E. Spinicingula ceratina Kozlova and Vishnevskaya sp. nov. B, C. From Narjan−Mar, borehole 5, Upper Volgian, sample 5. B. Holotype, VNIGRI N 667/66. C. VNIGRI N 667/66−1. D, E. From Upper Volgian, Gorodishce section (Craspedites subditus ammonite Zone) of Uljanovsk Volga Basin, sample G2. D. GIN N G−R1−1. E. GIN N G−R1−2. F, G. Parvicingula alata Kozlova and Vishnevskaya sp. nov., Middle Volgian, Gorodishce section (Dorsoplanites panderi Ammonite Zone) of Uljanovsk Volga Basin, sample G1. F. Holotype, GIN N G−1−2Ka. G. GIN N G−1−3K. H. Parvicingula papulata Kozlova and Vishnevskaya sp. nov., holotype, GIN N P−1K. Pechora Basin, Ukhta section, sample P, Lower Kimmeridgian. Scale bars 50 µm.