记甘肃晚侏罗世一蜥蜴新属

本文记述石龙子类 Scincomorpha 蜥蜴的—新属,甘肃拟贝氏蜥 Mimobefklesisaurus gansuensis gen. et sp. nov. 化石发现于甘肃省肃北县马宗山区晚侏罗世的赤金堡群.这是石龙子类化石在我国的第一次发现,也是目前所发现的这类动物在亚洲的最早的代表.

A NEW LIZARD FROM LATE JURASSIC OF SUBEI, GANSU

On the basis of an incomplete skeleton (IVPP no. V 7699), a new form of lizard, Mimobecklesisaurus gansuensis gen. et sp. nov. is described in this paper. The material, including a left fragmentary maxilla with teeth, a right ulna, a right femur and two scutes was collected from Upper Jurassic Chijinbu group of Subei county, Gansu province by a Regional Geological Team of Gansu. Diagnosis Pleurodont teeth small, conical and compressed lightly, closely arranged without enamel striation either on the libial or the lingual surface of the tooth; ulna rather slender with well developed olecranon; femur very strong, no separated trochanter internus on the simple proximal end; body osteoderm rectangular, possessing a central longitudinal keel, by which the scute surface separated into two slightly sloped parts with some pits irregular spread. Remarks Mimobecklesisaurus is inevitably a member of Scincomorpha by possessing a single cusp pleurodont teeth, and having body dermal scutes. The nearest affinity to Mimobecklesisaurus is found in Becklesisaurus, a European form from Upper Jurassic. In comparision with the latter, its teeth have smooth lingual surface rather than striated ones, and shows no tendency of removing the tooth cusp from the back of the tooth shaft (in anterior and middle of the jaw) to the middle (in the posterior of the jaw) as Becklesisaurus does. It seems that the new form differs from the other known lizards by the shape of tooth, and by the features of the femur and scutes.