Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 23. 2005. (Budapest, 2005)

Collimys dobosi n. sp Systematic description Order Rodentia BoWDICH, 1821 Family Muridae ILLIGER, 1811 Subfamily Cricetinae ROCHEBRUNE, 1883 Genus Collimys DAXNER-HÖCK, 1972 Collimys dobosi n. sp. Holotype — Figure 1: M

1

; N° 2003.79., Municipal Museum of Pásztó, Nógrád County Museums, Hungary. Derivatio nominis — Dedicated to DOBOS brothers: Mr. Zsolt DOBOS and Mr. László DOBOS who selflessly helped the author during the paleontological excavations of the last two decades. Type strata — Upper Sarmatian freshwater grey mud containing bones, terrestrial gastropods and ostracods. Material — 76 intact M

1 molars, 4 fragmentary M

1 molars; 80 intact M

2 molars, 2 fragmentary M

2 molars; 42 intact M

3 molars; 76 intact mi molars, 4 fragmentary mi molars; 76 intact rri2 molars, 2 fragmentary rri2 molars; 50 intact ms molars, 2 fragmentary ms molars Deposition — The material is stored in the Natural History Collection of the Municipal Museum of Pásztó (MMP) (Organization of the Nógrád County Museums) under the inventory numbers from 2003.1. to 2003.413. Diagnosis — Relatively large Collimys species with well developed and high transversal ridges of the occlusal surface (anteromesoloph, mesoloph, mesolophid, ectomesolophid). The lingual anterolophule in the M

2 is frequent. Flat chewing surface is developed in the adult ontogenetic phase involving the transversal ridges. The anterior region of the ml is variable: with one, two or three parted anteroconid and one, two or three branched anterolophulid. The ni3 tooth is relatively elongated. The degree of hypsodonty is higher than in C. transversus, but lower than in C. primus. Description of the holotype (Ns 2003.79., Figure 1) — Adult, moderately worn left upper M

1 molar. The anterocone is broad and undivided. The anterior surface of the anterocone is smooth and free of any sculpture and cingula. The protocone and the posterocentral part of the anterocone are connected by a relatively short and wide anterolophule. This anterolophule is connected to a transversal anteromesolophe. The higly developed enamel ridge reaches a small anteromesostyl in the buccal margin of the tooth crown. The protolophule I. is not developed. The posterobuccal angle of the protocone is connected to the wide protolophule II. The mesolophe is strong and highly developed but does not reach the buccal margin of the tooth crown. The mesostyle is not developed. The posteroloph is relatively straight and free of any conelets. The posterobuccal end of the posteroloph is connected to the basis of the metacone. The metalophule is posteriorly directed. A small enamel ring is closed by the metalophule, the metacone and the terminal part of the posteroloph. The sinuses are deep and narrow. Description of paratype N° 2003.207. (Figure 1) — A juvenile, unworn left lower mi molar. The anteroconid consists of two cusps and a cingulum is developed between the buccal part of the anteroconid and the basis of the protoconid. The anterolophulid is two branched (Vshaped). The lingual branch is connected to the lingual cusp of the anteroconid, the buccal branch is connected to the anterobuccal cingulum of the anteroconid. The anterolophulid is posteriorly linked with the protoconid and the anterolophulid. The mesolophid is highly developed and reaches the lingual margin of the tooth crown. A short ectomesolophid is developed, but mesostylid and ectostylid are not present. The posterolophulid is straight and connects the hypoconid and the posterior basis of the entoconid. The sinusids are deep and narrow. Description of the other specimens M

1 molars (Figures 2, 8, 9, 10) — The anterocone of the juvenile unworn teeth is undivided, edge-like and continued in a cingulum in the anterobuccal side up to the basis of the protocone. In the adult molars the anterocone is two parted, but never divided by notch. In the gerontic phase the anterocone is undivided again and similar to a Napoleon-cap. The anterolophule is short and during the wearing process got broader. The anteromesolophe is highly developed, always reaches the lingual margin of the molar (A variation in Table 1 and in Figure 8). In some cases, the anteromesoloph is not continuous, interrupted in the middle part (B variation in the Table 1 and in Figure 8). The conelet anteromesostyle is found in 65 molars (86 %). In the majority of the molars the protolophule I. is not developed. The protolophule II. is connected to the posterior angle of the protocone (p variation in Table 1 and in Figure 8). In a few molars the protolophule I. is connected to the anterior angle of the protocone and the paracone (a variation in Table 1 and in Figure 8). The simultaneous presence of the protolophule I. and II. is very rare (x variation in Table 1 and in Figure 8). The mesolophe is elevated and long. In 31 molars (39%) it reaches the buccal margin of the tooth crown (1 variation in Table 1 and in Figure 8), in 47 molars the mesolophe does not reach the buccal margin (0 variation in Table 1 and in Figure 8).