Bairdiocypris Kegel, 1932

Casier, Jean-Georges, Devleeschouwer, Xavier, Lethiers, Francis, Préat, Alain & Racki, Grzegorz, 2002, Ostracods and fore-reef sedimentology of the Frasnian-Famennian boundary beds in Kielce (Holy Cross Mountains, Poland), Acta Palaeontologica Polonica 47 (2), pp. 227-246 : 234-235

Genus Bairdiocypris Kegel, 1932

Type species: Bythocypris ( Bairdiocypris ) gerolsteinensis Kegel, 1932.

Bairdiocypris ventrorecta Casier and Lethiers , sp. nov. Fig. 5O–Q.

v. Bairdiocypris sp. nov. B, aff. angulata Janbulova in litt. sensu Kotschetkova and Janbulova, 1987; Casier and Lethiers 2000: pl. 2: 10a, b.

Derivation of the name: From Latin venter, venter and rectus, straight. Referring to the straight ventral border of the carapace.

Holotype: Carapace ( Fig. 5O, P). PG14. IRScNB n° b3795. L = 0.65 mm; H = 0.49 mm; W = 0.41 mm.

Type locality: Psie Górki section at Kielce, Holy Cross Mountains of Poland.

Material.—15 carapaces.

Diagnosis.— Bairdiocypris ventrorecta sp. nov. differs from other species of the genus Bairdiocypris in having a mid−sized, high, slightly preplete carapace with straight ventral and posterodorsal margins, a regularly arched dorsal border, and a diamond−shaped dorsal view with the anterior and the posterior extremities of the right valve depressed.

Description.—In lateral view, mid−sized, high, slightly preplete carapace. Dorsal margin strongly arched close to the mid−length. Ventral margin straight. Anterior margin regularly curved with the anterior extremity at mid−height. Posterior margin nearly straight dorsally, and strongly curved ventrally with the posterior angular extremity at lower third of height. Dorsal part of the posterior margin of the left valve straight and forming an angle with the dorsal margin. Ventral border of the right valve straight or slightly sinuous anteriorly. Maximum length at ventral third of height. Maximum height slightly anterior to the mid−length. Left valve overreaching the right one all around, except at the junction of the posterior and dorsal margins of the left valve. Slight ventral overlap. In dorsal view, carapace wide and diamond−shaped with the anterior and posterior extremities of the right valve depressed. Maximum width at mid−length. Carapace surface smooth.

Remarks.— Bairdiocypris ventrorecta sp. nov. resembles Bekena angulata Janbulova in litt. sensu Kotschetkova and Janbulova (1987) from the late Famennian (doVI) of Southern Ural, but differs from that species by a less angular dorsal border and posterior extremity not so much angular. In Bairdiocypris sp. nov. A, present in the Psie Górki and the Kostomłoty sections, the ventral margin is concave and the anterior margin nearly straight.

Occurrence.—Frasnian (PG3, PG6, PG11, PG14, PG29, PG30) in the Psie Górki section. Also in the Frasnian (KYA12, KYA19, KYA 29) of the Kostomłoty section.