Cardobairdia, van den Bold, 1960

Forel, Marie-Béatrice, Kolar-Jurkovšek, Tea & Jurkovšek, Bogdan, 2020, Ostracods from the ‘ Raibl Beds’ (Carnian, Late Triassic) of Belca section in Karavanke Mountains, northwestern Slovenia, Geodiversitas 42 (21), pp. 377-407 : 392-394

Cardobairdia ? sp.

( Fig. 8H )

EXAMINED MATERIAL. — One complete carapace and one right valve.

OCCURRENCE. — Nicoraella ? budaensis conodont zone, late Julian-?earliest Tuvalian, Carnian, Late Triassic, samples BE17, 18 ( Fig. 3 ), Belca section, ‘Raibl Beds’, Karavanke Mountains, Slovenia (this work).

DIMENSIONS. — L = 425 µm, H = 208 µm (BE17 [GeoZS6202]).

DISCUSSION

This species is rare in the sampled section and has only been found in samples BE17 and 18 ( Fig. 3 ). The genus Cardobairdia was described from the Middle Eocene of Trinidad (van den Bold 1960). Since then, it has been abundantly reported from Jurassic layers of western Tethys (e.g., Apostolescu 1959; Szczechura & Blaszyk 1968; Boomer 1991, 1992; Harloff & Jäger 1994; Monostori 1996; Boomer et al. 1998; Ainsworth & Boomer 2001; Olempska & Blaszyk 2001; N’Zaba-Makaya et al. 2003; Beher 2004). Until now, the oldest Cardobairdia was documented from the Early Jurassic of southern England ( Lord & Boomer 1988), of the Fastnet Basin off southwestern Ireland (Ainsworth 1986, 1987), of northern Wales (Boomer 1991) and of the continental slope off western Australia ( Lord et al. 1993). Noteworthy, the doubt on the generic attribution of the Belca’s specimens refers to the impossibility to observe their inner structures of the specimens and to confirm that the present material belongs to Cardobairdia such as described from Cenozoic deposits. However, the lateral morphology of Cardobairdia ? sp. from Belca conforms to the morphology of Jurassic occurrences, for which inner structures are most of the time not observed as well. In the present state of our knowledge, Cardobairdia ? sp. from the Belca section is the oldest occurrence of this genus worldwide.

Figures

FIG. 8. — Ostracods from the Belca section,Karavanke Mountains, northwestern Slovenia,Carnian,Late Triassic.All specimens are deposited in the micropalaeontology collections of the Geological Survey of Slovenia, under the numbers GeoZS6132 to GeoZS6239, preceded by sample number: A-E, Renngartenella sanctaecrucis Kristan-Tollmann in Kristan-Tollmann & Hamedani, 1973; A, lateral view of a right valve, BE2 (GeoZS6195); B, lateral view of a left valve, BE2 (GeoZS6196); C, lateral view of a right valve, BE2 (GeoZS6197); D, lateral view of a left valve, BE2 (GeoZS6198); E, lateral view of a right valve, BE2 (GeoZS6199); F, Hungarella sp. 1, lateral view of a right valve, BE18 (GeoZS6200); G, Hungarella sp. 2, lateral view of a right valve, BE18 (GeoZS6201); H, Cardobairdia? sp., right lateral view of a complete carapace, BE17 (GeoZS6202); I-U, Issacharella bisulcata Kozur, 1972 emend. Kristan-Tollmann in Kristan-Tollmann et al. 1991b; I, lateral view of a right valve, BE18 (GeoZS6203); J, lateral view of a left valve, A-5, BE21 (GeoZS6204); K, lateral view of a right valve, A-4, BE2 (GeoZS6205); L, lateral view of a left valve,A-4,BE2 (GeoZS6206);M, lateral view of a right valve,BE2 (GeoZS6207);N, lateral view of a right valve,BE18 (GeoZS6208);O, lateral view of a left valve,A-3, BE2 (GeoZS6209); P, left lateral view of a carapace,A-2, BE17 (GeoZS6210); Q, lateral view of a right valve, BE21 (GeoZS6211); R, lateral view of a left valve, A-1, BE17 (GeoZS6212); S, lateral view of a right valve, A-1, BE2 (GeoZS6213); T, left lateral view of a carapace, Adult, BE17 (GeoZS6214); U, lateral view of a left valve, Adult, BE18 (GeoZS6215). Scale bars: 100 μm.

FIG. 3. — Distribution of ostracod species through the Belca section, Karavanke Mountains, northwestern Slovenia.