Lamprothamnium sp.

(Fig. 6 I-L)

DESCRIPTION

Medium-sized gyrogonites, 432-648 µm high (mean 547 µm) and 297-513 µm wide (mean 434 µm), elongate, prolate to sub-cylindrical in shape, with an isopolarity index ranging from 111-163 (mean

127). Apex lamprothamnoid, truncated, showing a marked periapical depression due to decreasing cell thickness. Ŋe base is rounded with a small basal pore (45 µm). Spiral cells flat to convex, without ornamentation. Eight to ten (frequently nine) convolutions are visible in lateral view.

REMARKS

A population from Sant Bartomeu del Grau (NE Ebro Basin) belongs to the genus Lamprothamnium according to the general sub-cylindrical shape and the apical structure (Table 2). Gyrogonites of Lamprothamnium sp. from sample CC-1 is similar in gyrogonite width and convolution number to the Lower Eocene Lamprothamnium priscum Castel & Grambast, 1969 . However, gyrogonites from the Ebro Basin are about 115 µm shorter, resulting in a more rounded morphology.Poor preservation hinders their specific attribution.