Cepola anderssoni Schwarzhans & Mors & Engelbrecht & Reguero & Kriwet 2017, sp. nov.

Cepola anderssoni sp. nov.

(Figs 5Q, R, 6R)

Material. Holotype: NRM-PZ P.15996 (Figs 5Q, R, 6R) (only specimen, broken into two halves during handling).

Occurrence. Telm 5 unit; ‘ Natica horizon’, Cucullea I member, La Meseta Formation, late Ypresian, early Eocene. Site IAA 2/95, Seymour Island, Antarctica.

Etymology. Named in honour of Johan Gunnar Andersson, a Swedish pioneer of geological research in Antarctica.

Diagnosis. OL:OH = 1.85. Dorsal rim shallow, with broadly rounded postdorsal angle. Rostrum sharp; posterior tip less sharp. OsL:CaL = 2.1; OCL: CCL = 2.0. Ostial colliculum reduced anteriorly, terminating at considerable distance from anterior rim of otolith. Outer face flat.

Description. Otolith elongate, thin, 4.4 mm long. OH:OT = 3.2. Dorsal rim shallow, gently curving, smooth, with broadly rounded postdorsal angle and highest at postdorsal angle. Ventral shallow, very regularly curving, highest at its middle, smooth. Rostrum long and sharp; dorsal margin of ostial opening regularly ascending without marked excisura or antirostrum. Posterior tip pointed, but considerably less sharply and projecting as rostrum.

Inner face convex with distinctly supramedian positioned narrow sulcus. Sulcus typically S-shaped with cauda being curved upwards from collum prior to terminating with an inferior tip. Ostium twice as long as cauda, slightly wider and narrower. Ostial colliculum not extending to opening of ostium to anterodorsal otolith rim. Collum ascending, wide, with feeble pseudocolliculum. Cauda very short, its small colliculum distinctly deepened. Dorsal depression large, well marked towards sulcus; ventral furrow feeble, running moderately distant from ventral rim of otolith. Outer face flat and smooth.

Remarks. Cepolid otoliths are well known from the Eocene of Europe represented by a number of species (see Nolf 2013). Of those, Cepola excavata (Stinton, 1978) and C. bartonensis Schubert, 1916 resemble the proportions of the otolith (Nolf 2013; Schwarzhans 2007), while other species are more compressed (C. densa (Frost, 1934) and C. robusta Nolf, 1988). Cepola anderssoni differs from all those species by the anteriorly restricted ostial colliculum and the very small cauda. Cepola yrieuensis Steurbaut, 1984 from the early Oligocene of south-west France is similar in the short cauda, but differs in the distinct postdorsal angle (vs. rounded postdorsal region) and the ostial colliculum reaching to or close to the anterior rim (vs. anteriorly restricted).