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International audience; The internal endocranial structures of an undescribed atoposaurid crocodylomorph from the Sao Khua Formation (Cretaceous: Berriasian-Barremian) in the North-East of Thailand are investigated. The specimen is comparable in size and external morphology to Theriosuchus grandinaris Lauprasert et al. 2011 but is preserved with the braincase uncrushed, contrary to the previously described holotype. We document for the first time the internal braincase structures in atoposaurids using synchrotron X-ray micro-computed tomography. The endocast of the braincase, associated nerves and arteries, auditory labyrinth, and cranial pneumatization, although quite deformed, are reconstructed at high resolution and compared to those of extant and fossil crocodylomorphs, representative of different ecological adaptations. This atoposaurid specimen shows an antero-posterior brain curvature and pericerebral spines (new structures), somewhat developed cerebral hemispheres, expanded semicircular canals with a more developed anterior one but an almost straight lateral one, a dorsoventrally expanded pituitary fossa, but also overdeveloped intertympanic diverticula and pharyngotympanic sinuses. The ecologicalsignificance of these structures is explored and, using different proxies and comparisons with extant taxa, we suggest that this specimen likely exhibited a downwardly tilted head posture (by about 10◦) and was sensitive to both low and mid frequencies. Functional comparisons are proposed between this specimen, extinct terrestrial crocodylomorphs (sebecosuchians), extant semi-aquatic crocodilians and aquatic (thalattosuchians) forms. From the morphology of the auditory labyrinth, we infer an enhanced sensitivity to pitching rather than yawing. Several hypotheses are formulated regarding the pneumatization of the skull. These features are discussed in ecological and phylogenetic frameworks. Our results highlight the need to gather new data, especially on altirostral forms, in order to deepen our understanding of the evolution of endocranial structures in crocodylomorphs with different ecological specializations, as well as to integrate them into new phylogenetic approaches.

Nonsrirach, Thanade, Lauprasert, Komsorn (2019): Preliminary report on the genetic structure of Glyphoglossus molossus (Anura: Microhylidae) from the Khorat Plateauı north-eastern Thailand. Journal of Natural History 53 (13): 849-861, DOI: 10.1080/00222933.2019.1618940

Glyphoglossus molossus, is one of the most economically important amphibians in the Khorat Plateau, north-eastern Thailand. It is categorised as a near-threatened species by IUCN due to over-exploi...

KRABISUCHUS GEN. NOV. Type species: Krabisuchus siamogallicus sp. nov. Etymology: The generic name is based on the locality, ‘Krabi’, in which the holotype was found and the Egyptian ‘souchos’ for crocodile. Diagnosis: As for the species, by monotypy.

Martin, Jeremy E., Lauprasert, Komsorn (2010): A new primitive alligatorine from the Eocene of Thailand: relevance of Asiatic members to the radiation of the group. Zoological Journal of the Linnean Society 158 (3): 608-628, DOI: 10.1111/j.1096-3642.2009.00582.x, URL: http://dx.doi.org/10.1111/j.1096-3642.2009.00582.x

Lauprasert Komsorn, Cuny Gilles, Buffetaut Éric, Suteethorn Varavudh, Thirakhupt Kumthorn. First occurrences of Atoposaurid Crocodyliforms in the Late Jurassic and Early Cretaceous of the Khorat Plateau, northeastern Thailand. In: Documents des Laboratoires de Géologie, Lyon, n°164, 2008. Mid-Mesozoic life and environments. Cognac (France), June 24th-28th 2008. pp. 59-61.