Ernestokokenia sp.

Fernández, Mercedes, Zimicz, Ana N., Bond, Mariano, Chornogubsky, Laura, Arnal, Michelle, Cárdenas, Magalí & Fernicola, Juan C., 2021, New Eocene South American native ungulates from the Quebrada de los Colorados Formation at Los Cardones National Park, Argentina, Acta Palaeontologica Polonica 66 (1), pp. 85-97 : 87

cf. Ernestokokenia sp.

Fig. 1A .

Material.—IBIGEO-P 65, fragmented left upper cheek tooth from Quebrada Grande, Los Cardones National Park, Casamayoran SALMA, Eocene.

Description.—Despite the fact that IBIGEO-P 65 is a very fragmented material, what is preserved shows some morphological features in the occlusal surface that resembles closely Ernestokokenia . There is a bunoid protocone that is connected to the metaconule by a well-defined crest, and which is separated from a well-developed and bunoid hypocone by a lingual sulcus; a broken distal cingulum can be identified.

Remarks. —In Northwestern Argentina, these archaic ungulates are unusual and are represented until now by scarce and incomplete material. López (1997) described an isolated lower molar as cf. Ernestokokenia for the Geste Fm. (late Eocene) at Antofagasta de la Sierra (Catamarca). Based on an astragalus collected in the same unit, Armella et al. (2016) mentioned the presence of Ernestokokenia cf. E. yirunhor . More recently, Gelfo et al. (2020) mentioned a new bunodont Didolodontidae , based on a mandibular fragment with associated dentition, from the Lumbrera Fm., near San Antonio de Los Cobres (Salta).

Figures

Fig. 1. New fossil materials of Litopterna,Astrapotheria, and Notostylopidae from the Quebrada de Los Colorados Formation exposed at Quebrada Grande locality, Los Cardones National Park (Salta Province), Casamayoran SALMA, Eocene. A. cf. Ernestokokenia sp. (IBIGEO-P 65), fragmented left upper cheek tooth in occlusal view.B.Astrapotheria indet.(IBIGEO-P 66), left maxillary fragment with three broken molariforms in lingual (B1) and occlusal (B3) views, and detail showing Hunter-Schreger bands (B4); dashed area in B2 indicates broken or missing dental areas. C. Homalostylops sp. (IBIGEO-P 57b), right m2? in occlusal (C1), lingual (C3), and labial (C4) views. D.?Homalostylops sp. (IBIGEO-P 57a), left m1? in occlusal view. Photographs (A1, B1, B3, B4, C1, C3, C4, D1), explanatory drawings (A2, B2, C2, D2).