Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 64. (Budapest 1972)

Jánossy, D.: Middle Pliocene microvertebrate fauna from the Osztramos Loc. 1. (Northern Hungary)

Spalacidae Prospalax MÉHELY, 1908 Prospalax kretzoii sp. n. Derivatio nominis: „kretzoii" from Dr. MIKLÓS KRETZOI, my teacher in vertebrate paleontology. Stratum locusque typicus : Osztramos. locality 1. (further particulars see at the description of Amblycoptus topali). Age: Middle Pliocene (,,Postpannonian Pliocene"). Diagnosis : Typical Prospalax, with considerably larger dimensions than the hitherto known fossil representatives. Holotype: right mandible with the M

2 and M

3

, the fragmentary incisor and the ascending ramus (broken and later newly cemented with the corpus mandibulae). Inv. Nr. V. 71. 50. No referred specimens, only the holotype known. Description : Mandible with typical features of the genus Prospalax: Spalaxlike form, but the ascending ramus without processus incisivus and the incisor with three longitudinal ridges on the outer side. M

L lacking. The crown of M

2 and M

3 with S-shaped enamel folds, as usual in the Spalacidae, yet not only larger but in the antero-posterior direction more compressed than in Prospalax priscus. The whole mandible is much more massively built than in the latter species. To show the absolute differences in size, I give the measurements as follows (compared with P. priscus as well as with P. petteri): P. kretzoii priscus Weze petteri Kohfidisch External depth of mandible beneath M, or M

2 ±8 5.3 Alveolar (n=26) length MJ-M

3 10.2 0.0-9.0 5.9-6.5 M

2 (n = 144) (n = 2) length X width 2.8x2.4 1.5-2.6x1.3-2.0 1.8-2.4X1.6-1.9 M

3 (n = 65) (n=2) length X width 2.5X2.3 1.3-2.2x1-2-1.8 1.5-1.7x1-3-1.5 width of (n = 34) lower incisor 2.2 1.7-2.0 — Comparisons: Two species were hithero described from this genus: Prospalax priscus (NEHRING, 1897), and Prospalax petteri BACHMAYER & WILSON, 1970; both are considerably smaller, as apparent in the table of measurements above. Some -related species, described from Beresti and Malusteni (SIMIONESCU, 1922. 1930). are also smaller and considered by some authors congeneric and conspecific with Prospalax prisctis (NEHRING) (Pliospalax simionescui KORMOS, 1932, P. macovei SIMIONESCU, 1922, and P. roumanus SIMIONESCU", 1922). According to the latest investigations by KRETZOI (1971, manuscript). Pliospalax represents a quite different and distinct evolutionary line leading to the modern Spalax branch; Prospalax would not be a Spalacid but an Anomalomyid.