Pseudodryomys ibericus De Bruijn 1966
Creators: name: Crespo, Vicente Daniel
name: Ríos, María
name: Marquina-Blasco, Rafael
name: Montoya, Plini
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Rodentia
Gliridae
Pseudodryomys
Pseudodryomys ibericus

description: Pseudodryomys ibericus De Bruijn, 1966
(Fig. 7)
LOCALITIES. — MCX1, MCX3, MCX7, MTR2, BC1, FS1, MAB0A, MAB0B, MAB3, MAB3A, MAB5, MAB8, MAB11, MAB11B, CBR0B, CBR0C, CBR0G, CBR1, and CBR4.
MATERIAL. — MCX1: 1 M2; MCX3: 1 m2, 1 D4, 1 P4, 1 M1; MCX7: 1 P4, 1 M1, 1 M2; MTR2: 1 m3, 1 M1; BC1: 2 p4, 1 m3, 1 D4, 1 P4, 1 M3; FS1: 1 m1, 1 m2, 2 P4; MAB 0A: 2 D4, 1 P4, 1 M3; MAB 0B: 1 P4, 1 M2; MAB 3: 2 p4, 2 m1, 5 m2, 1 m3, 2 D4, 1 P4, 5 M1, 3 M2, 2 M3; MAB 3A: 1 p4, 1 m2, 1 M1, MAB 5: 1 d4, 2 p4, 2 m1, 2 m3, 1 P4, 1 M3; MAB 8: 1 d4; MAB 11: 1 m1, 1 M2; MAB 11B: 1 D4; CBR 0B: 2 m1, 1 D4, 1 P4; CBR 0C: 1 D4; CBR 0G: 1 D4; CBR 1: 1 D4, 1 P4, 1 M3; CBR 4: 1 m1.
MEASUREMENTS. — Appendix 10
DESCRIPTION
d4 (MAB5)
The tooth has a subtriangular shape. The anterolophid is short and connected to the anteroconid and the protoconid. The metalophid is a spur of the protoconid. The mesolophid is long and has a small ridge on the antero-labial side. The mesolophid contacts the posterolophid, forming a large ellipse closed at the lingual side, and with a low connection on the labial part. A posterotropid is present. The posterolophid is thin and relatively short. The morphology of the material from MAB8 is simpler than the one described above, with no extra crestids and with the anterolophid connected only to the metalophid.
p4 (MAB 3)
The tooth is subtriangular and hypsodont. The anterolophid may be short (1 out of 2) or absent (1 out of 2). The metalophid may be merely a posterior spur of the anterolophid (1 out of 2) or long (1 out of 2) and curved to form almost an ellipse. The endolophid may be small (1 out of 2) or absent (1 out of 2). The mesolophid is long, connected to a well-developed posterolophid. In the p4 from BC1 the mesolophid and the posterolophid are irregular and divided into several parts. The specimen from MAB 3A has a metalophid divided in two and a long centrolophid. The material from MAB 5 shows a mesolophid that contacts the posterolophid forming a large ellipse closed on the lingual side and with a low connection on the labial side.
m1 (MAB 5)
Tooth rectangular in shape with high crestids and narrow valleys. The anterolophid is short. The metaconid is connected to the anteroconid. The metalophid is curved and long, in one specimen it is divided into three parts. The centrolophid is well developed up to the middle part of the tooth. The mesolophid and the posterolophid may be isolated (1 out of 2) or connected (1 out of 2). The posterotropid may be long and isolated (1 out of 2), or it may be connected to the lingual part (1 out of 2). The labial cuspids are more developed than the lingual cuspids. The posterior valley is the widest one. The specimens found in CBR 4 are similar to the one described above. In FS1 the metalophid is straighter. In MAB 3 the anterolophid is longer, and this crestid has a posterior spur. In MAB 11 the anterolophid is longer, with a small extra cuspid behind the centrolophid. In CBR 0B the centrolophid is divided in two.
m2 (MAB 3)
Sub-rectangular tooth with high crestids and narrow valleys. The anterolophid may be medium to long (2 out of 4) or short (2 out of 4). The metaconid is connected to the anteroconid. The metalophid is straight and long, with a narrower part that almost separates it from the metaconid; a posterior spur in the middle of the tooth may connect the metalophid to the mesolophid (1 out of 4), to the centrolophid (1 out of 4) or it may be absent (2 out of 4). The centrolophid is well developed up to the middle of the tooth and isolated on the lingual side, in two cases it is connected to the endolophid. The mesolophid and the posterolophid are long and connected on the lingual part (3 out of 4) or not connected (1 out of 4). The posterotropid is either long and independent (1 out of 4) or attached to the lingual side (3 out of 4). The labial cuspids are more developed than the lingual ones. The posterior valley is the widest one. The specimens found in MCX3, FS1 and MAB 3A follow the previous description.
m3 (MAB 3)
The tooth is slightly reduced, D-shaped in occlusal view, and more or less elongated. The anterolophid is long. The metalophid is long and slightly curved. The endolophid is developed. The anterior centrolophid is long, almost reaching the middle of the tooth. The mesolophid is long and straight. The mesolophid and the posterolophid are well connected. Both the posterior valley and the posterolophid are well developed. The specimens found in MTR2 are similar to the one described above. The specimen in BC1has the shortest centrolophid. In MAB 5 the metalophid may be isolated, and a posterotropid may appear in the posterior valley.
D4 (MAB 3)
The tooth has a subtriangular outline, with fine crests and wide valleys. The anteroloph may be long, but shorter than the posteroloph and it may be either attached to the protoloph on the labial side (1 out of 2) or long, isolated and divided in two (1 out of 2). The protoloph and the metaloph are long and contact each other forming a Y-shape. The centroloph may be a small cusp (1 out of 2) or be absent (1 out of 2). The protocone is poorly developed. The posteroloph is long and it may be connected on the labial face (1 out of 2) or on both faces (1 out of 2). There are two open roots. The specimens found in CBR 1 fit in this description. In MCX3 the posteroloph is isolated on both sides. In BC1 the tooth is more rounded. In MAB 0A the anteroloph is shorter, there are two centrolophs, a short anterior one and a long posterior one, which contacts the protoloph and the posteroloph may be isolated. In the material of MAB 11B, CBR 0B, CBR 0C, and CBR 0G there is a long postcentroloph connected on both sides.
P4 (MAB 3)
Tooth with a subrounded outline. The anteroloph is long and isolated. The protoloph and the metaloph are long and contact with the protocone, forming a V-shape.The protoloph is divided into two parts. The protocone is poorly developed. The posteroloph is long and independent. In MCX3 the anteroloph is short and the protocone is more developed. In MCX7 and BC1 there is a medium-sized centroloph. In FS1 and MAB 0B the teeth have a short centroloph, or this last crest is connected to the metaloph while the posteroloph is connected on both sides. In MAB 0A there is a short centroloph and the posteroloph is connected on the labial side. In MAB 5 the protoloph and the metaloph form a Y-shape and the metaloph is divided in two parts, which meet with the posteroloph. The centroloph in CBR 0B is short. In CBR 1, MCX3, MCX7, BC1, MAB 0A, MAB 5 and CBR 0B the protoloph and the metaloph form a Y-shape.
M1 (MAB 3)
Tooth square with broad crests and valleys. The anteroloph is long and isolated. The protoloph and the metaloph may form a V (2 out of 4) or a Y (2 out of 4). The precentroloph may be short (1 out of 5) or of medium size (4 out of 5), and it is shorter than the posterior centroloph. The postcentroloph is longer than half the width of the tooth and it may be isolated on both sides (2 out of 5), it may contact the metaloph on both sides (2 out of 5), or it may form a Y-shape with the precentroloph (1 out of 5). The posteroloph is short and isolated. The specimens found in MAB 3A are similar to the ones just described. In MCX3 and MCX7 the anteroloph is shorter and the posteroloph is lingually connected and longer. The MTR 2 specimen shows a longer posteroloph.
M2 (MAB 3)
The tooth is square in shape and with broad crests and valleys. The anteroloph is long, lingually isolated and with a low connection on the labial side. The protoloph and the metaloph may form the typical U (1 out of 2) or V shape (1 of 2), connecting at the lingual side. The precentroloph is short and the postcentroloph is long and joins the metaloph on the lingual side, it may be isolated on the labial side (1 out of 2) or of similar size with a cusp on the labial side where the two crests connect (1 out of 2). One specimen shows a low connection between the two centrolophs. The posteroloph is intermediate in size, connected lingually to the protocone and isolated labially. The specimens found in MCX7 fit in the description above. In MCX1 the anteroloph is isolated and there is a prototrope. In MAB 0B the anteroloph is isolated, and the protoloph-metaloph together with the centrolophs form a Y. In MAB 11 only the protoloph-metaloph forms a Y.
M3 (MAB 3)
The tooth is sub-rectangular in outline. The anteroloph is long and forms a closed ellipse with the protoloph, although on the labial side the contact is low. In two specimens the lingual end of the anteroloph does not contact the protoloph. The precentroloph is short and the posterior is longer than the anterior one. The protoloph and the metaloph do not contact until they reach the lingual side, forming a U-shape. The metaloph and the posteroloph do not contact on the labial side. The posteroloph is short. In BC1, the anteroloph is long and contacts on the labial side of the protoloph and it is isolated on the lingual side, and the metaloph and the posteroloph contact on the labial side, but in the middle of the metaloph. In MAB 0A the specimen has only a postcentroloph. In MAB 5, the metaloph and the posteroloph contact on both sides. In CBR 1 the specimen has only a postcentroloph and the protoloph and the metaloph meet in a Y-shape near the lingual side.
REMARKS
Pseudodryomys is another genus with a problematic taxonomic status due to its possible synonymy with Peridyromys and Myomimus (see discussion above), as indicated by Dalmasso et al. (2022). The species Ps. ibericus is one of the most widespread dormice, both temporally and geographically (Daams 1999a). Remains of this species are found from the early-Lower Miocene to the Middle Miocene in much of Europe (Daams 1999a). This species differs from P. murinus in its larger size, greater complexity, and higher number of crests. It differs from Pr. satus in its larger size and more developed crests. The morphology of the premolars and third molars of Ps. ibericus can be easily confused with other species from this period, and especially with those of P. murinus.
Pseudodryomys ibericus has already been described from the sites of Araya and Mas de Antolino 2 (Agustí et al. 1988). In general, this species does not have a great morphological variability, presenting a similar size among the different sites under study. Although it is very abundant in other basins, it is scarce in the sites under study. Morphologically, our material is like that from other basins, upper molars correspond to morphotype C and lower molars to morphotype L, as described by Daams (1974). Biometric data show that the upper molars are slightly smaller than those from the Calatayud- Montalbán Basin whereas the lower molars are of similar size (Daams 1974; García-Paredes et al. 2009).
description: Published as part of Crespo, Vicente Daniel, Ríos, María, Marquina-Blasco, Rafael & Montoya, Plini, 2023, They are all over the place! The exceptional high biodiversity of dormice in the Early Miocene of the Ribesalbes-Alcora Basin (Spain), pp. 589-641 in Geodiversitas 45 (20) on pages 605-608, DOI: 10.5252/geodiversitas2023v45a20, http://zenodo.org/record/10137206