Armantomys cf. daamsi (de Visser, 1991)

Ruiz-Sánchez, Francisco J., Murelaga, Xabier, Larrasoaña, Juan C., Freudenthal, Matthijs & Garcés, Miguel, 2012, Hypsodont Myomiminae (Gliridae, Rodentia) from five new localities in the Lower Miocene Tudela Formation (Bardenas Reales, Ebro Basin, Spain) and their bearing on the age of the Agenian-Ramblian boundary, Geodiversitas 34 (3), pp. 645-663 : 655-656

Armantomys cf. daamsi (de Visser in Álvarez-Sierra, Daams, Lacomba, López Martínez, Van Der Meulen, Sesé & De Visser, 1991)

( Fig. 4 Q-R)

LOCALITY AND AGE. — Cabezo Carboneras 1 (CC1), Province of Navarre, Spain. Agenian (Local subzone Y2, MN2).

MATERIAL AND MEASUREMENTS (L × W). — CC 1-31 (13.76 estimated × 14.04), right M1; CC 1-38 (11.71 × 15.80), left M2.

DESCRIPTION

M1

Anteroloph joined to paracone and separated from the protocone by a deep furrow. Protoloph oblique and continuous. Near the paracone the protoloph presents a short, forward directed, spur. Metaloph low connected to protoloph. Postcentroloph short. Posteroloph connected to protocone and metacone.

M2

Anteroloph slightly oblique, connected to the protocone and separated from the paracone by a deep furrow. Protoloph continuous without spurs. Metaloph connected to protoloph, forming a Y-pattern. No centroloph ridges. Posteroloph slightly oblique and high connected to the protocone.

REMARKS

Two specimens from Cabezo Carboneras 1 (CC1) ( Fig. 4Q, R ) have been assigned to A. cf. daamsi on the basis of size, the presence of a posterior centroloph in M1 and the kind of connections between metaloph and protoloph in M1,2. The presence of an anterior and/or posterior centroloph is dominant in populations of Armantomys from the Upper Agenian and Lower Ramblian ( Daams 1990). On the other hand, in CC1-31 ( Fig. 4Q ), a short spur on the anterior side of the protoloph is present. This feature appears in populations of Armantomys from Upper Agenian to Middle Aragonian. The presence of spurs on the protoloph of M1,2 is frequent in A. parsani and dominant in A. jasperi from the Lower Ramblian; it has been cited in some specimens of A. daamsi from the Upper Agenian ( Daams 1990). Therefore, on the basis of morphology, size and the scarcity of the material we assign these specimens to A. cf. daamsi .

Figures

FIG. 4. — A-E, Armantomys cf. bijmai from Cabezo Hermoso 1 (CH1): A, left M2,CH1-6;B, right M3,CH1-8; C, right P4,CH1-4;D, right D4, CH1-5; E, right m1, CH1-3; F-M, Armantomys daamsi from Cuesta Agujeros 2 (CA2): F, left M1, CA2/1-6; G, right M2, CA2/1-5; H, right M2, CA2/2-6; I, right M3, CA2/1-15; J, right P4, CA2/1-12; K, left m1, CA2/1-8; L, left m1, CA2/1-10; M, right m3, CA2/2-5; N, Armantomys cf. jasperi from Cuesta Agujeros 4 (CA4), fragmentary right m2, CA4/1-27; O, P, Armantomys cf. parsani from Cuesta Agujeros 3 (CA3): O, left M2, CA3-1; P, left P4, CA3-2; Q, R, Armantomys cf. daamsi from Cabezo Carboneras 1 (CC1): Q, right M1, CC1-31; R, left M2, CC1-38; S, cf. Praearmantomys crusafonti from Cabezo Carboneras 1 (CC1), right m3, CC1-22. Scale bar:1 mm.