Dixonius siamensis (BOULENGER, 1899)
Can you confirm these amateur observations of Dixonius siamensis?
|Higher Taxa||Gekkonidae, Gekkota, Sauria, Squamata (lizards: geckos)|
|Common Names||E: Siamese Leaf-toed Gecko|
|Synonym||Phyllodactylus siamensis BOULENGER 1899: 918|
Phyllodactylus paviei MOCQUARD 1904 (fide SMITH 1935)
Phyllodactylus burmanicus ANNANDALE 1905 (fide SMITH 1935)
Phyllodactylus siamensis — SMITH 1935: 81
Phyllodactylus siamensis — TAYLOR 1963: 750
Phyllodactylus siamensis — WERMUTH 1965: 144
Phyllodactylus siamensis — KLUGE 1993
Dixonius siamensis — BAUER et al. 1997
Phyllodactylus siamensis — COX et al. 1998: 89
Dixonius siamensis — CHAN-ARD et al. 1999: 117
Dixonius siamensis — RÖSLER 2000: 77
Dixonius siamensis — NGUYEN et al. 2009
|Distribution||Thailand, Annam, Siam (Dung-Phya-Fai), Vietnam, Laos, Cambodia ?|
Type locality: Dung-Phya Fai Mountains, eastern Siam.
|Types||Syntypes: BMNH 1918.104.22.168-41, 22.214.171.124-2|
|Diagnosis||Diagnosis (genus): Amongst others, the presence of precloacal pores, the tuberculate dorsum, the reduction in length of phalanx 2 of digit IV of the manus, and the proximally bifurcate hypoischium are characteristic features that serve to diagnose this genus from all other leaf-toed geckos (Bauer et al. 1997).|
|Comment||Karyotype: Dixonius siamensis consists of karyologically different populations. Specimens from E Thailand had 2n = 40 chromosomes while specimens from NW Thailand invariably had 2n = 42 chromosomes (Ota et al. 2001).|
Distribution: Reports from India and Myanmar are in error (A. Bauer, pers. comm. 30 Aug 2011).
Type species: Phyllodactylus siamensis BOULENGER 1899 is the type species of the genus Dixonius.
Sumontha et al. (2017) believe that the interpretation of the type locality of Phyllodactylus paviei by Das (2004: 629) is erroneous. Das (2004) matched Mocquard’s ‘‘Vatana’’ with ‘‘Chaeng Wattana, ca. 13°45’N, 100°31’E: a northern suburb of Bangkok, across the highway from the airport, Phra Nakhon Province, Thailand’’. Mocquard’s description of P. paviei appeared in the lizard chapter of a book dedicated to the study of the scientific results of the expedition of the French explorer Auguste Pavie in Indochina in 1879–1895. In the introduction of the book, a map, however locates ‘‘Vatana’’ just southeast of ‘‘Srakeo’’, and it thus certainly corresponds to Watthana Nakhon (13°43'49.13"N, 102°20'5.76"E; elev. 72 m asl), Watthana Nakhon District, in the eastern province of Sa Kaeo which borders Cambodia. The type locality reported by Das (2004) was an incorrect interpretation and was further repeated by Ngo & Ziegler (2009). Watthana Nakhon lies about 198 airline km E of Chaeng Watthana, and is located southeast of the type localities of both D. melanostictus and D. siamensis.
|Etymology||The genus has been named after James R. Dixon (1 August 1928 – 10 January 2015) who spent most of his academic life at Texas A&M University. The species is named after its occurrence in Thailand, formerly “Siam”.|