Scholars Crossing Faculty Publications and Presentations Department of Biology and Chemistry 2016 A New Snail-Eating Turtle of the Genus Malayemys Lindholm, 1931 (Geoemydidae) from Thailand and Laos Timothy R. Brophy Liberty University, [email protected] M. Sumontha K. Kunya S. Wiboonatthapol O.S.G. Pauwels Follow this and additional works at: https://digitalcommons.liberty.edu/bio_chem_fac_pubs Part of the Aquaculture and Fisheries Commons Recommended Citation Brophy, Timothy R.; Sumontha, M.; Kunya, K.; Wiboonatthapol, S.; and Pauwels, O.S.G., "A New Snail-Eating Turtle of the Genus Malayemys Lindholm, 1931 (Geoemydidae) from Thailand and Laos" (2016). Faculty Publications and Presentations. 120. https://digitalcommons.liberty.edu/bio_chem_fac_pubs/120 This Article is brought to you for free and open access by the Department of Biology and Chemistry at Scholars Crossing. It has been accepted for inclusion in Faculty Publications and Presentations by an authorized administrator of Scholars Crossing. For more information, please contact [email protected]. MAJOR ARTICLE TAPROBANICA, ISSN 1800–427X. March, 2016. Vol. 08, No. 01: pp. 1–9, pls. 1–10. © Research Center for Climate Change, University of Indonesia, Depok, Indonesia www.taprobanica.org LSID:urn:lsid:zoobank.org:pub:D8B85741-6094-4A02-8772-DB2FB05D223E A NEW SNAIL-EATING TURTLE OF THE GENUS Malayemys LINDHOLM, 1931 (GEOEMYDIDAE) FROM THAILAND AND LAOS Section Editor: Thasun Amarasinghe Submitted: 21 January 2016, Accepted: 18 February 2016 Montri Sumontha1, Timothy R. Brophy2, Kirati Kunya3, Suthep Wiboonatthapol4 and Olivier S. G. Pauwels5 1 Ranong Marine Fisheries Station, 157 Saphanpla Rd., Paknam, Muang, Ranong 85000, Thailand; E-mail: [email protected] 2 Department of Biology and Chemistry, Liberty University, 1971 University Boulevard, Lynchburg, Virginia 24502 USA; E-mail: [email protected] 3 Nakhonratchasima Zoo, 111 M. 1, Ratchasima-Pak Tongchai Rd., Chaimongkol, Muang, Nakhon Ratchasima 30000, Thailand; E-mail: [email protected] 4 Khamsaenwittayasan School, 8 M. 10, Na Klang, Na Klang, Nong Bua Lamphu 39170, Thailand; E-mail: [email protected] 5 Département des Vertébrés Récents, Institut Royal des Sciences naturelles de Belgique, Rue Vautier 29, 1000 Brussels, Belgium; E-mail: [email protected] Abstract We describe a snail-eating turtle, Malayemys isan sp. nov., from the Mekong River Basin in northeastern Thailand (Nong Bua Lamphu, Nong Khai and Udon Thani provinces) and the adjacent Vientiane area in Laos. The new species is readily distinguishable from M. subtrijuga by its two (vs. six to nine) nasal stripes, and from both M. subtrijuga and M. macrocephala by its thin, often discontinuous, infraorbital stripe that never reaches the loreal seam. This geographically-restricted new species is sold in several food markets throughout the species‟ distribution and is in urgent need of conservation measures. Keywords: Aquatic ecosystems, biodiversity, herpetofauna, Mekong, snail-eating turtle Introduction subtrijuga (Schlegel & Müller, 1844) and a Brophy (2002, 2004, 2005) performed a taxon he revalidated, M. macrocephala (Gray, morphological revision of the genus Malayemys 1859). These two species are allopatric and Lindholm, 1931, that was until then regarded by found in different hydrographic basins: while the most authors as monospecific, and concluded latter occurs in the Chao Phraya and Mae that it was actually composed of two well- Khlong river basins, coastal areas of distinguished species, the recognized M. southeastern Thailand and the Malay Peninsula, 01 TAPROBANICA VOL. 08: NO. 01 A NEW SNAIL-EATING TURTLE OF THE GENUS Malayemys M. subtrijuga is restricted to the Mekong River line), CWV2-3 (carapace width at the level of Basin. Morphometric ratios of both species the seam between 2nd and 3rd vertebrals, widely overlap, but they are easy to differentiate measured in straight line), RLPS (relative based on their number of nasal stripes (four or lengths of plastral scale seams). Abbreviations: less in M. macrocephala, and six or more in M. Ab, abdominal; An, anal; F, femoral; G, gular; subtrijuga) and extent/width of infraorbital H, humeral; P, pectoral). stripe (not extending beyond the loreal seam, or Museum abbreviations: CUB, only slightly in M. macrocephala, and extending Chulalongkorn University Museum of Zoology, completely superior to the loreal seam in M. Bangkok, Thailand; IRSNB, Institut Royal des subtrijuga; relatively wide at loreal seam in M. Sciences Naturelles de Belgique, Brussels, macrocephala, and relatively narrow at loreal Belgium; PSUZC-RT, Prince of Songkhla seam in M. subtrijuga). The revalidation of M. University Zoological Collection, Reptile macrocephala by Brophy (2004), based on the section, Songkhla, Thailand; QSMI, Queen thorough examination of more than two hundred Saovabha Memorial Institute, Thai Red Cross specimens from all parts of the genus‟ range Society, Bangkok, Thailand; RMNH.RENA, where material was available, has been accepted Rijksmuseum van Natuurlijke Historie by many authors working on the Southeast (=Netherlands Centre for Biodiversity Asian turtle fauna (see among others Pauwels & Naturalis), Leiden, Netherlands; THNHM, Chan-ard, 2006; Keithmaleesatti et al., 2009; Natural History Museum, National Science Pewphong et al., 2013; Siripiyasing et al., 2013; Museum, Technopolis, Pathum Thani, Thailand; van Dijk et al., 2014). ZMKU, Zoological Museum of Kasetsart In the course of our systematic University, Bangkok, Thailand. inventories of the Thai herpetofauna (see latest contribution by Pauwels et al., 2016), we came Results across a population of Malayemys in Malayemys isan new species northeastern Thailand, in a region that was not (Figs. 1–6, 7A, 9B, 10; Table 1) represented by the museum material in Brophy‟s (2004) revision. Even though this population is Malayemys subtrijuga––Stuart & Platt, 2004: 135. Malayemys subtrijuga––Kubota et al., 2015: 23. found in the heart of the Mekong River Basin, where only M. subtrijuga has been found so far LSID:urn:lsid:zoobank.org:act: (Brophy, 2005), it was strikingly different 6D1A31B9-8960-42CE -97D5-0F48AF46FD7A because of its consistent possession of only two nasal stripes while M. subtrijuga shows six or Holotype: THNHM 25609 (field number MS more. We consequently performed a comparison 571), adult female collected from Ban Na Klang between this population and the two currently (17°14'48.728"N, 102°12'32.479"E), Na Klang recognized species, and conclude that it Sub-district, Na Klang District, Nong Bua represents a new taxon, described below. Lamphu Province, northeastern Thailand. Paratypes (6 specimens): adult males: Materials and Methods ZMKU Rep-000318 (field number MS 573) and We examined a total of 223 museum preserved PSUZC-RT 716 (field number MS 574); specimens from the whole distribution range of subadult male: QSMI 1396; adult females: the genus Malayemys (see Appendix I), CUMZ-R-0.2321 (field number MS 572) and including the type specimens of M. PSUZC-RT 717 (field number MS 575); macrocephala and M. subtrijuga, as well as live juvenile: QSMI 1395 (field number MS 577); specimens. We also analyzed all photographs same locality data as holotype. and morphological information available in both Diagnosis: The new species is a the Thai and the international literature (see medium-sized Malayemys species reaching a references in Brophy, 2002, 2004, 2005, and maximum carapace length of at least 152 mm in references cited below). The holotype and males and 206 mm in females, characterized by paratypes of the new species were preserved in the consistent combination of (1) only two nasal 70% ethanol. Measurements were done on the stripes, (2) a thin, often discontinuous, preserved type series with a vernier caliper to infraorbital stripe that never reaches the loreal the nearest 0.1 mm. Morphology: CL (maximum seam, (3) an uninterrupted supraorbital stripe, carapace length, measured in straight line), CW and (4) the absence of stripes or light spots (maximum carapace width, measured in straight between the infra- and supraorbital stripes. 02 TAPROBANICA VOL. 08: NO. 01 SUMONTHA ET AL., 2016 Description of holotype: Adult female. joining its symmetric stripe, forming in dorsal Habitus similar to Malayemys macrocephala and view a V on the snout. No additional stripe or M. subtrijuga. Head large (head width 49.2 light spots between the infraorbital and the mm), snout projecting anteriorly. Upper jaw supraorbital stripes. Two parallel nasal stripes medially notched, with a broad and flat trituring extend from the nostrils to the medial notch of surface and a very slight medial ridge. Carapace the upper jaw. Neck, upper surfaces of members oval, moderately arched, unserrated but notched and tail gray. Throat light gray with irregular, posteriorly. Maximum carapace length 206.3 diffuse, cream spots. Body skin and lower mm. Maximum carapace width 153.4 mm. surface of members and tail light gray. Chin Carapace width at the level of the seam between scute cream-colored with black markings. One 2nd and 3rd vertebrals 146.1 mm. Cervical scale cream- and black-colored large scale on each triangular, pointing forward. Twelve marginal side of the posterior angular extremity of the scales on each side. Five vertebral scales, wider chin scute. than long. Each of the vertebral scales shows a Variation: Measurements on the type poorly marked median longitudinal keel, higher series are provided in Table 1. The three anterior in the