Malayemys khoratensis IHLOW, VAMBERGER, FLECKS, HARTMANN, COTA, MAKCHAI, MEEWATTANA, DAWSON, KHENG, RÖDDER & FRITZ, 2016
Can you confirm these amateur observations of Malayemys khoratensis?
|Higher Taxa||Geoemydidae (Geoemydinae), Testudinoidea, Testudines (turtles)|
|Common Names||Thai: Tao na Isan|
English: Isan Snail-eating turtle, Khorat snail-eating turtle
French: Malayémyde d’Isan
|Synonym||Malayemys khoratensis IHLOW, VAMBERGER, FLECKS, HARTMANN, COTA, MAKCHAI, MEEWATTANA, DAWSON, KHENG, RÖDDER & FRITZ 2016|
Malayemys isan SUMONTHA, BROPHY, KUNYA, WIBOONATTHAPOL & PAUWELS 2016
Malayemys subtrijuga — STUART & PLATT 2004: 135
Malayemys subtrijuga — KUBOTA et al. 2015: 23
Malayemys khoratensis — KWET 2017
Malayemys khoratensis — TTWG 2017
Malayemys khoratensis — THOMSON & LAMBERTZ 2017
Malayemys khoratensis — TTWG 2021
|Distribution||NE Thailand (Nakhon Ratchasima)|
khoratensis: Type locality: “Udon Thani, Udon Thani Province, Thailand (17.36555°N, 102.81427°E)”
isan: Type locality: Ban Na Klang (17°14'48.728"N, 102°12'32.479"E), Na Klang Sub-district, Na Klang District, Nong Bua Lamphu Province, northeastern Thailand
|Types||Holotype: THNHM 25609 (field number MS 571), adult female.|
Paratypes (6 specimens): adult males: ZMKU Rep-000318 (field number MS 573) and PSUZC RT 716 (field number MS 574); subadult male: QSMI 1396; adult females: CUMZ-R-0.2321 (field number MS 572) and PSUZC RT 717 (field number MS 575); juvenile: QSMI 1395 (field number MS 577); same locality data as holotype.
Holotype: THNHM 25816, young, adult female (Fig 6) from Udon Thani, Udon Thani Province, Thailand (17.36555°N, 102.81427°E, WGS 1984), collected in July 2014 by FI and MC; Paratypes: THNHM 25999, adult female, Udon Thani, Thailand); ZFMK 97198, adult male, Udon Thani, Thailand; MTD 49150, female, Udon Thani, Thailand. [khoratensis]
|Diagnosis||Diagnosis (isan): The new species is a medium-sized Malayemys species reaching a maximum carapace length of at least 152 mm in males and 206 mm in females, characterized by the consistent combination of (1) only two nasal stripes, (2) a thin, often discontinuous, infraorbital stripe that never reaches the loreal seam, (3) an uninterrupted supraorbital stripe, and (4) the absence of stripes or light spots between the infra- and supraorbital stripes.|
Diagnosis (khoratensis): Malayemys species with a straight carapace length below 20 cm and a tricarinate, blackish-brown carapace, and a blackish-brown head with distinct yellowish facial stripes. Malayemys khoratensis differs from M. macrocephala by the following characters: (1) first ver- tebral scute roughly square and not tapered posteriorly (V1W/V1L: 0.83±0.09 vs. 0.74±0.19 in females, 0.83±0.12 vs. 0.69±0.09 in males); (2) lower marginal scutes 8–12 with a pattern of diagonal to cone-shaped blackish brown blotches originating from the outer posterior corner vs. narrow blackish-brown bars at the posterior sutures; (3) infraorbital stripe not or rarely reaching the loreal seam, not broadened at the suture vs. always reaching the loreal seam and usually distinctly broadened at the suture; (4) infraorbital stripes only slightly curved below of tyrosine (T) at positions 111, 387, 388,615, 616 of the 1078-bp-long reference alignment of the cyt b gene (S1 FASTA).
|Comment||Malayemys isan was described in a paper published on 26 March 2016 while that of M. khoratensis was published on 6 April 2016. The two species are synonymous based on O. Pauwels, pers. comm., 9 April 2016. TTWG 2017 decided to give khoratensis priority as isan did not comply with ICZN rules (Zoobank registration) of online publications. This was confirmed by Thomson & Lambertz 2017.|
Distribution: see map in Ihlow et al. 2016.
Habitat: aquatic, in shallow, stagnant or slow-moving freshwater bodies
Behavior: nocturnal (Sumontha et al. 2016), but also diurnal (F. Ihlow, pers. comm. 19 April 2016).
|Etymology||„Isan‟ is a Thai word designating the northeastern region of Thailand, where the type locality of the new species lies. It is here used as a noun in apposition, invariable.|
M. khoratensis was named after the Khorat Basin, the watershed to which the range of the new species appears to be restricted.