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Two crocodilian anterior cranium parts from Takut Khon Village sand pit, Chaloem Phrakiat District, Nakhon Ratchasima Province, are presently described. Their morphology indicates that the specimens belong to a single species based on the presence of several similar characters such as a hole for the reception of the first dentary tooth at the anterior edge of the premaxillary bone; anterior tip of nasal elongate and projecting into the posterior margin of the external nares; wavy suture line between the posterior part of the nasal with the anterior margin of prefrontal and frontal processes. The cranium morphology is extremely close to Crocodylus siamensis Schneider, 1801 (Siamese crocodile) and conforming the existence of C. siamensis from the Middle Pleistocene in Thailand. [ABSTRACT FROM AUTHOR]

Skull and mandibular elements of a tomistomine crocodilian are described from the late Eocene to early Oligocene lignite seams of Krabi, peninsular Thailand. The Thai tomistomine is a longirostrine form characterized by a rostrum/skull ratio of about 0.6; a mandibular symphysis reaching the level of the eleventh alveolus; a deep participation of the splenial in the symphysis to the level of the ninth alveolus; an enlarged fifth maxillary alveolus; long nasals reaching the premaxillae at the level of the fifth maxillary alveolus but not contributing to the external nares; undivided posterior processes of premaxillae; a short prefrontal, excluded by a longer lacrimal from the posteromedial margin of maxillae; vomers visible on the palate. A phylogenetic analysis recovers the Thai specimen among derived tomistomines, on the stem lineage of the extant Tomistoma schlegelii , as a close ally of Maomingosuchus petrolica , a late Eocene tomistomine from southern China. The present recognition of Maomingosuchus sp. in late Eocene Thai deposits expands the distribution of Eocene tomistomines from southern China to the tropics. The origin of Tomistominae in Asia is briefly discussed. [ABSTRACT FROM AUTHOR]

Abstract: The Mesozoic vertebrate fauna from Kut Island includes hybodont sharks (Hybodus sp., Isanodus paladeji, a new species of Heteroptychodus), actinopterygians (Semionotiformes indet., Lepidotes sp.), indeterminate turtles, goniopholidid crocodiles, cf. Theriosuchus sp. and theropod dinosaurs. The new hybodont species is also present in the Sao Khua Formation and maybe also in the Phu Kradung Formation on the Khorat Plateau in northeastern Thailand. The occurrence of both I. paladeji and the new hybodont, together with heavily ornamented Semionotiformes teeth strongly suggest that this fauna is of the same age as the Sao Khua Formation one. Deposits from Kut Island are therefore younger than usually considered, and not older than Berriasian. [Copyright &y& Elsevier]

Giant tortoises have been found from the Plio-Pleistocene sediments of Tha Chang sandpits, Nakhon Ratchasima Province, Thailand. These tortoises are represented by several individuals and are described based on carapace, plastron, limb bones, and isolated plates. Three different morphotypes of epiplastral projection are recognized, pertaining to different sexes or different ontogenetic stages. Based on their large size, thick shell, single supracaudal, well-developed epiplastral projection, gulars covering anterior part of the entoplastron or in contact with the latter, and humeropectoral sulcus posterior to entoplastron, these Thai giant tortoises are assigned to the genus Megalochelys. Thai specimens show strong similarities with large tortoises from India as well as those from Flores and Timor, and are therefore very close morphologically to Melgalochelys atlas. Our study provides new evidence about polymorphism and additional information about distribution of Plio-Pleistocene fossil giant tortoises in South and Southeast Asia. [ABSTRACT FROM AUTHOR]

This is a morphological analysis of the osteoderm patterns of Indosinosuchus from the Late Jurassic Phu Noi excavation site in Kalasin Province, Thailand. Data on 203 specimens indicated that 197 osteoderms belongs to the teleosaurid genus Indosinosuchus. Out of 203 total, 109 specimens are dorsal osteoderm morphotypes (M1 to M5) with sub-square, sub-rectangular, or rhomboidal in shape, including keel and peg. Another 88 are ventral osteoderms (M6 and M7) with rectangular or sub-square osteoderms, obscure keel and peg. Large subcircular ellipsoid pits with an anterior facet bar are discovered in both dorsal and ventral osteoderms. Data on morphological features enabled osteoderm positions of Indosinosuchus to be described. The anterior cervical osteoderms are characterized by an obscure keel and a small sub-square shape (M1). In the posterior trunk region, the osteoderms increase in width and adopt a sub-rectangular shape (M2). These osteoderms decrease in size at the sacral level (M3) with a more pronounced keel. The osteoderms gradually decrease in size as they adopt a rhombus shape towards the caudal region (M4) until the caudal end (M5). The ventral osteoderms, with a lack of keel and peg, exhibit a rectangular shape in the central region (M6), while a square or sub-square shape is observed along its lateral margin (M7). Six specimens are could not be assigned to Indosinosuchus and were described as morphotype 8 (M8). This morphotype has distinct characteristics resembling the ventral osteoderms of Mesoeucrocodylia that are yet to be described. The discovery of Indosinosuchus and Mesoeucrocodylia osteoderms suggests a diverse range of crocodyliformes in the Phu Noi fossil excavation site with potential for future studies. [ABSTRACT FROM AUTHOR]

Abstract: In the last ten years, several fossil localities in Nakhon Ratchasima Province (northeastern Thailand) have yielded late Neogene turtle and crocodile taxa. Although not always well dated, the age of all these fossils is constrained between Middle Miocene and Pleistocene. Several crocodile taxa have been discovered: Crocodylidae, Alligatoridae and Gavialidae. In particular, the presence of Gavialis is attested in northeastern Thailand during the Pleistocene. Fossil turtles belong to several families: Geoemydidae, Testudinidae, and Trionychidae. In addition to the discovery of giant continental tortoises, some large aquatic trionychid and geoemydid turtles are present. The latter are only found in larger river systems and no longer encountered in the Mun or Chi Rivers of northeastern Thailand. Most fossil forms correspond to modern species and reveal interesting changes in biogeographical distribution patterns. These changes are likely related to changes in the size of the drainage and direction of the Mun River system. We suggest that the Mun River was probably not flowing from west to east to the Mekong River system as today but that it was flowing from east to west to the Chao Phraya River system. [Copyright &y& Elsevier]