Bairdia (Bairdia)

Maillet, Sebastien, Milhau, Bruno, Vreulx, Michel & Posada, Luis-Carlos Sánchez De, 2016, Givetian ostracods of the Candás Formation (Asturias, North-western Spain): taxonomy, stratigraphy, palaeoecology, relationship to global events and palaeogeographical implications, Zootaxa 4068 (1), pp. 1-78 : 53

Bairdia (Bairdia) sp. P2

(Pl. IV: Fig. 3 )

2013 Bairdia (Bairdia) sp. P2; Maillet: 161, pl. XXV, fig. 6.

Material. 2 specimens (2 C).

Description. Medium-sized elongated carapace, subhexagonal in lateral view, biconvex in dorsal view. Overlap of the larger LV over the RV along whole outline, more marked dorsally than ventrally. Bow-shaped projection in ventral view. Hmax at 1/3 posterior; Lmax at 2/5 ventral; Wmax antero-ventral. Dorsal margin straight for the smaller RV and slightly convex for the larger LV in its middle part (on about 1/3 of Lmax), and anteriorly and posteriorly oblique for both valves. Ventral margin straight to slightly convex for both valves and posteriorly oblique. Dorsal and ventral margins slightly converging posteriorly. Sharp anterior and posterior ends. Anterior margin oblique in its dorsal and ventral parts, straight for the larger LV and a little more concave for the smaller RV, forming a rounded angle of about 90° at the carapace end. Posterior margin also oblique in its dorsal and ventral parts, forming a rounded angle of about 85° at the carapace end. Anterior end of the carapace slightly higher than the posterior one. Anterior part of the carapace higher than the posterior one. Surface smooth. Inflated node at mid-length in the dorsal part of the carapace on both valves.

Discussion. A mid-dorsal node is an atypical character for the Bairdia genus, hence the species remains unidentified. Moreover, the collected specimens are most probably juvenile because the anterior part of the carapace is more developed than the posterior one (see Pl. IV: Fig. 3 ).

Occurrences. Middle Givetian (Candás Fm, mbs A and C), Asturias (Peran-Perlora section).

Figures

FIGURE 3. Stratigraphical distribution of ostracod taxa through the Candás Formation in the Peran-Perlora and Carranques sections. Samples numbers are replaced on a detailed stratigraphical column of the series, on which macro- and microfaunas’ occurrences are indicated.