Tethylamna cf. twiggsensis (Case, 1981)

EXAMINED MATERIAL. — 50 isolated teeth, figured material includes FSAC Bouj-331, 332, 333, 334, 335 and 336.

DESCRIPTION

Numerous teeth are attributed to odontaspidid Tethylamna cf. twiggsensis. This species is easily recognizable by a pair of double flat cusplets on anterior (Fig. 3A, F) and lateral teeth (Fig. 3 C-E).

REMARKS

The range of this species is currently restricted to the latest Lutetian-late Priabonian and its geographic distribution extends to paleotropical seas between tropical eastern Pacific, Caribbean and oriental Neotethys (Casier 1971; Case 1981; Case & Borodin 2000; Case & Cappetta 1990; Ward & Wiest 1990; Adnet et al. 2007; Underwood et al. 2011; Cappetta & Case 2016). Originally described from the late Eocene of Georgia, United States (Case 1981), distinction between the middle and the late Eocene representatives are sometimes controversial. The Bartonian teeth have lateral cusplets less pronounced compared to those from Priabonian (Underwood et al. 2011) explaining why they are often referred to confer twigssensis. These Bartonian samples could corresponds to intergradual change from the possible ancestor T. dunni of Cappetta & Case (2016) recovered from the Lutetian of Alabama, USA toward those of Priabonian, including type of species (Case 1981).