Berdanella

Berdanella sp. P1

(Pl. I: Fig. 15)

? 1989 Kirkbyella (Berdanella) igesohni nov. sp.; Becker, 135–136, pl. 1, figs. 6–8. 2013 Berdanella sp. P1; Maillet: 64, pl. VI, fig. 20.

Material. 1 specimen (1 V).

Description. Small elongated and equivalve carapace, rounded sub-rectangular outline in lateral view, arrowhead-shaped in dorsal view. Hmax slightly anterior; Lmax at 2/5 dorsal; Wmax in the postero-ventral part (at ridge extremity). Straight hinge line and dorsal margin. Adductorial sulcus slightly anterior to mid-dorsal. Slightly convex ventral margin. Well rounded and regularly convex anterior margin, forming an angle of about 130° with the dorsal margin. Slightly rounded posterior margin, more arched in its ventral part, forming an angle of about 100° with the dorsal margin. Anterior part of the carapace slightly higher than the posterior one. Free margins of the carapace flattened. Lateral bar in the ventral half of each valve long of 2/3 of Lmax and more prominent in its posterior part, forming lateral robust wings in dorsal view. Surface finely reticulated.

Discussion. This single specimen reminds of Kirkbyella (Berdanella) igesohni Becker, 1989 from the Eifelian from the Palencia, but the carapace of this species is shorter with a dorsal margin not as straight as our specimens.

Occurrence. Middle Givetian (Candás Fm, mb C), Asturias (Peran-Perlora section).