Miocene fossil vertebrates from the nong hen-i(a) exploration well of thai shell exploration and production company limited, phitsanulok basin, Thailand

The first early to middle Miocene terrestrial mammalian fauna from Thailand (the Nong Hen Local Fauna) was recovered at a depth between 887 and 894 meters in the Thai Shell Exploration and Production Company Ltd. Nong Hen-I(A) well located in the northern part of the country. More than 100 mammalian jaws and teeth were recovered. Most specimens were from a single new species of bat, Mormopterus ( Hydromops) nonghenensis but two other bats were also present as well as a small rodent and some other, larger mammal. The preponderance of bats in this assemblage is concordant with its having been recovered from a karst deposit. The stage of evolution of M. ( H.) nonghenensis suggests that the Nong Hen Local Fauna is late early to middle Miocene in age.