Leh, Charles Moi Ung

Mohd Izwan Zulaini, Abdul Gani

Muhammad Amirul Arib, Md Adzhar

Nur Fatimah, Mohd Azizi

Rambli, Ahmad

Ruhana, Hassan

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Trends in Undergraduate Research (2018) 1(1): a23-32  23/32  A Taphonomic Study of Crocodylus porosus (Crocodylidae) and Tomistoma schlegelii (Gavialidae) Remains from Western Sarawak, Malaysian Borneo: Applications for Public Education RUHANA HASSAN*1, NUR FATIMAH MOHD AZIZI1, MUHAMMAD AMIRUL ARIB MD ADZHAR1, MOHD IZWAN ZULAINI ABDUL GANI1, RAMBLI AHMAD2 & CHARLES LEH MOI UNG3 1Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia; 2Sarawak Forestry Corporation, Lot 218, KCLD, Jalan Tapang, Kota Sentosa, 93250 Kuching, Sarawak, Malaysia; 3The Sarawak Museum, Barrack Road, 93000 Kuching, Sarawak, Malaysia *Corresponding authors: hruhana@unimas.my ABSTRACT This study documented details of the dentitions, skulls and other skeletal remains of Crocodylus porosus and Tomistoma schlegelii, from western part of Sarawak, Malaysian Borneo. The remains of both reptiles were exhumed, followed by standard cleaning procedures and then detail morphological assessments were carried out accordingly. Both species show similar structure of vertebral columns, but T. schlegelii has the following unique structures: a long and narrower snout, D-shaped eye sockets, long and sharp pointed protruding quadratojugal bones, straight maxillae and dentary, a smooth surfaced skull, elongated triangular suborbital fenestrae, round shaped internal nares and visible supraoccipital from a dorsal view. C. porosus has heterodont dentition with blunt-pointed and irregular size of teeth whereas T. schlegelii has almost homodont dentition with sharp and similar size teeth. This is the first collection of teeth, skulls and other skeletal remains of both species obtained from Sarawak, and the materials have been used regularly to educate the public through science exhibitions, hoping they will spark the interests of young budding scientists to be involved in wildlife taphonomic studies in the future. Keywords: Crocodylus porosus, dentition, reptile, skeletal remain, Tomistoma schlegelii Copyright: This is an open access article distributed under the terms of the CC-BY-NC-SA (Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License) which permits unrestricted use, distribution, and reproduction in any medium, for non-commercial purposes, provided the original work of the author(s) is properly cited.  INTRODUCTION The saltwater crocodile, Crocodylus porosus has a wide distribution, ranging from Australia, Bangladesh, Brunei, Mynmar, Timor Leste (East Timor), India (including Andaman and Nicobar Islands), Indonesia, Malaysia, Palau, Papua New Guinea (including Bismark archipelago and other island chains), the Philippines, Sri Lanka and Solomon Islands (Britton, 2012). C. porosus (locally name: “Buaya Katak” or “Buaya Air Masin”) and Tomistoma schlegelii (local name: “Buaya Jejulung”) are found in Sarawak (Hassan et al., 2016; Stuebing, Bezuijen, Auliya & Voris, 2006). Previously, both C. porosus and T. schlegelii were in the same family namely Family Crocodylidae but later evidence from nuclear gene inferences had placed T. schlegelii into Family Gavialidae (Willis, McAliley, Neely, & Densmore, 2007). In Sarawak, the existence of T. schlegelii is less known compared to C. porosus, probably due to the secretive nature of the latter species (Hassan et al., 2016). The distribution of T. schlegelii is limited to the lowland regions of western Sumatra, Kalimantan and western Java (Indonesia), Sarawak and Peninsular Malaysia. T. schlegelii is classified in Appendix I of the Convention on International Trade of Endangered Species of Wild Fauna and Flora (CITES) (Bezuijen, Shwedick, Sommerlad, Stevenson & Stuebing, 2010; Webb, Manolis & Brien, 2010). For C. porosus in Sarawak, various conservation efforts, including strict law enforcement, had been successful, leading to the increased in populations over the 30-years period as reflected in the state crocodile surveys involving all 21 river basins (Zaini, Ripot, Ubang, Francis & Simon, 2014). In 2016, Sarawak has been successful in transferring C. porosus from Appendix I to Appendix II of CITES, providing opportunity for sustainable management of the wild resource for the benefit of local people. The documentation on the density and ecology of C. porosus in Sarawak had been carried out by Bezuijen et al. (2010), Cox and Gombek (1985), Gani (2014), Gani and Hassan (2013), Hassan and Gani (2013), Hassan, Adzhar, Gani and Ahmad (2018) as well as Zaini et al. (2014). Research on T. schlegelii in Sarawak could be referred to Bezuijen, Shwedick, Simpson and Stuebing (2014), Cox and Gombek (1985), Hassan et al. (2016), Md Adzhar and Hassan (2017), Pine (2013), Stuebing, Sah, Lading and Jong (2003) and Stuebing et al. (2006).   

A Taphonomic Study of Crocodylus porosus (Crocodylidae) and Tomistoma schlegelii (Gavialidae) Remains from Western Sarawak, Malaysian Borneo: Applications for Public Education

http://ir.unimas.my/id/eprint/25124/1/A%20Taphonomic%20Study%20of%20Crocodylus%20porosus%28Crocodylidae%29%20%28abstract%29.pdf

A Taphonomic Study of Crocodylus porosus (Crocodylidae) and Tomistoma schlegelii (Gavialidae) Remains from Western Sarawak, Malaysian Borneo: Applications for Public Education

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