New Vertebrate Fossil Site from the Early Cretaceous Sao Khua Formation, Sakon Nakhon Province, Northeastern Thailand

Phornphen Chanthasit,Haiyan Tong,Kamonlak Wongko,Teppei Sonoda,Wilailak Naksri,Suravech Suteethorn

doi:10.4236/ojg.2019.910057

Abstract

A new vertebrate fossil site, “Phu Sung” in Sakon Nakhon Province was discovered. Various vertebrate fossils belonging to fresh water shark, bony fish, turtle, crocodile and dinosaur were found in reddish silty mudstone of the Early Cretaceous Sao Khua Formation of the Khorat Group. Crocodilian remains including a complete skull and partial articulated skeleton are very well preserved associated with turtle remains. Moreover, well preserved 19 turtle shells were found accumulated together. These discoveries will certainly fulfill our knowledge about these aquatic taxa from the Early Cretaceous Sao Khua Formation. The exceptional preservation of Phu Sung fossils could probably relate to the paleoenvironment in the Early Cretaceous of Thailand.

Highlights

Various vertebrate fossils belonging to fresh water shark, bony fish, turtle, crocodile and dinosaur were found in reddish silty mudstone of the Early Cretaceous Sao Khua Formation of the Khorat Group
Well preserved 19 turtle shells were found accumulated together. These discoveries will certainly fulfill our knowledge about these aquatic taxa from the Early Cretaceous Sao Khua Formation
The exceptional preservation of Phu Sung fossils could probably relate to the paleoenvironment in the Early Cretaceous of Thailand

Summary

Introduction

The Lower Cretaceous Sao Khua Formation of the Khorat Group mainly distributed in northeastern Thailand (Figure 1), is well known for the rich fossils especially for dinosaurs. Some Sao Khua fossil sites in Sakon Nakon were previously mentioned about the discoveries of vertebrate remains including fresh. A new vertebrate fossil site “Phu Sung” was firstly found by a forest ranger in the National Reserved Forest of Phu Lom Khao and Phu Peg area. Several vertebrate fragments, such as dinosaur, crocodile and turtle were found on the surface obviously in the intermittent rills. In December 2018, the excavation was proceeded and found the exceptionally preserved articulated crocodile and turtles remains which kind of preservation has rarely reported from the Lower Cretaceous of Thailand

Geological Setting

Fossil Assemblage