Agerinia smithorum sp. nov., a new early Eocene primate from the Iberian Peninsula

Abstract

The new species Agerinia smithorum (Adapiformes, Primates) from the early Eocene of the Iberian Peninsula is erected in this work. An emended diagnosis of the genus is provided, together with a broad description of the new species and comparisons with other samples assigned to Agerinia and other similar medium-sized cercamoniines. The new species is based on the most complete specimen of this genus published to date, a mandible preserving the alveoli of the canine and P1 , the roots of the P2 and all teeth from P3 to M3 . It was found in Casa Retjo-1, a new early Eocene locality from Northeastern Spain. The studied specimen is clearly distinguishable from other cercamoniines such as Periconodon, Darwinius, and Donrussellia, but very similar to Agerinia roselli, especially in the similar height of P3 and P4 and the general morphology of the molars, therefore allowing the allocation to the same genus. However, it is undoubtedly distinct from A. roselli, having a less molarized P4 and showing a larger paraconid in the M1 and a tiny one in the M2 , among other differences. The body mass of A. smithorum has also been estimated, ranging from 652 to 724 g, similar to that of A. roselli. The primitive traits shown by A. smithorum (moderately molarized P4 , large paraconid in the M1 and small but distinct in the M2 ) suggest that it could be the ancestor of A. roselli.

Agerinia marandati sp. nov., a new early Eocene primate from the Iberian Peninsula, sheds new light on the evolution of the genus Agerinia

“…Indeed, A. marandati shows a set of intermediate features between A. smithorum and A. roselli , suggesting that it represents a transitional step in the evolution of this lineage. Therefore the description of this new species reinforces the idea of the ancestor-descendant relationship between the other mentioned species, as proposed by Femenias-Gual et al (2016b). These trends are supported by the stratigraphic position of the studied localities: as explained, the type locality of A. marandati , Masia de l’Hereuet, is situated in an upper stratigraphic position with respect to Casa Retjo-1, type-locality of A. smithorum .…”

“…Regarding Agerinia smithorum from Casa Retjo-1 (Femenias-Gual et al, 2016b), it is also very similar in size to A. marandati (Fig. 6).…”

“…Measurements of Periconodon helveticus have been taken directly on high-resolution casts. Data of Agerinia roselli and Agerinia marandati after Femenias-Gual et al (2016a) and Femenias-Gual et al (2016b), respectively; data of Darwinius masillae after Franzen et al (2009); data of Donrussellia gallica after Russell, Louis & Savage (1967); data of Donrussellia louisi , Donrussellia russelli, Periconodon lemoinei and Periconodon huerzeleri after Gingerich (1977); data of Donrussellia lusitanica after Estravís (2000); data of Donrussellia magna after Godinot et al (1987); data of Donrussellia provincialis after Godinot (1981); data of Periconodon jaegeri after Godinot (1988); data of Periconodon helleri after Thalmann (1994); data of Asiadapis cambayensis and Marcgodinotius indicus after Rose et al (2007) and Rose et al (2009). …”

“…However, only a few contributions have been published regarding European primates from the early Eocene, recently including the revision of Agerinia roselli from Les Saleres and the description of the new species Agerinia smithorum from Casa Retjo-1 (Femenias-Gual et al, 2016a and Femenias-Gual et al, 2016b, respectively). The former work allowed for the identification of several traits of A. roselli that were not described previously, such as the presence of two roots situated mesially with respect to the P 3 or the presence of a tiny paraconid on the M 1 .…”

First early Eocene lizards from Spain and a study of the compositional changes between late Mesozoic and early Cenozoic Iberian lizard assemblages

“…The analysis of several concentrates held at Institut Català de Paleontologia Miquel Crusafont (ICP) revealed the presence of numerous Eocene lizard remains (Bolet and Evans, 2010a), and new material has been recovered in the last years after additional fieldwork. Many of the Eocene localities with samples in the collection are important in yielding fossil primates that have been object of several studies (e.g., Marigó et al, 2013Marigó et al, , 2016Minwer-Barakat et al, 2012, 2013Femenias-Gual et al, 2016a, 2016b. The present paper concerns those localities of an early Eocene age that have yielded interesting lizard material.…”