{{Short description|Species of snake}} {{Use dmy dates|date=January 2020}} {{Speciesbox |image = Trimeresurus ayerwadyensis.png |genus = Trimeresurus |species = ayerwadyensis |authority = Kin Onn Chan, S. Anuar, A. Sankar, I. T. Law, I. S. Law, R. Shivaram, C. Christian, D. G. Mulcahy, and A. Malhotra, 2023 }}
'''''Trimeresurus ayerwadyensis''''', also known [[Common name|commonly]] as the '''Ayerwady green pit viper''' or '''Southern Myanmar green pit viper''', is a species of snake.
== Description == In terms of color pattern, ''Trimeresurus ayeyarwadyensis'' shares characteristics with both ''T. purpureomaculatus'' and ''T. erythrurus''. For example, specimen <abbr>CAS</abbr> 213410 from Yangon is bright green with no dorsal markings (Fig. 4A) and is virtually identical to ''T. erythrurus'' (Fig. 4B). A photograph of an unvouchered live specimen from Yangon corroborates this observation (Fig. 5). Contrastingly, <abbr>CAS</abbr> 219764 from Pyapon District in the Ayeyarwady Region has a dark or olive-green base dorsal coloration with distinct dark blotches (Fig. 4C) reminiscent of ''T. purpureomaculatus''—albeit ''T. purpureomaculatus'' does not have a green base dorsal coloration (Chan et al. 2022). On the other hand, <abbr>CAS</abbr> 212245 from Myaungmya District in the Ayeyarwady Region appears to be an intermediate of the other two specimens in having a dark or olive-green base dorsal coloration with no distinct blotches (Fig. 4D). Despite these variations, all three specimens were unambiguously shown to represent a distinct, monophyletic lineage that is not conspecific with either ''T. purpureomaculatus'' or ''T. erythrurus'' (Chan et al. 2023). The distinct evolutionary trajectory of the new species coupled with the lack of morphological differentiation makes ''T. ayeyarwadyensis'' sp. nov. an archetypal example of a true cryptic species.<ref>{{Cite journal |last1=Chan |first1=Kin Onn |last2=Anuar |first2=Shahrul |last3=Sankar |first3=Ananthanarayanan |last4=Law |first4=Ingg Thong |last5=Law |first5=Ing Sind |last6=Shivaram |first6=Rasu |last7=Christian |first7=Ching |last8=Mulcahy |first8=Daniel G. |last9=Malhotra |first9=Anita |date=2023-12-13 |title=A new species of pit-viper from the Ayeyarwady and Yangon regions in Myanmar (Viperidae, Trimeresurus) |journal=ZooKeys |language=en |issue=1186 |pages=221–234 |doi=10.3897/zookeys.1186.110422 |pmid=38312859 |pmc=10836646 |bibcode=2023ZooK.1186..221C |doi-access=free |issn=1313-2970}}</ref>
== Distribution and habitat == ''Trimeresurus ayeyarwadyensis'' occurs at [[Hlawga Park]] in the [[Yangon Region]] and [[Pyapon]] and [[Myaungmya]] districts in the [[Ayeyarwady Region]]. The northern and western limits of its distribution likely lie somewhere in between the [[Myaungmya|Myaugmya]] and [[Pathein]] districts in the [[Ayeyarwady Region]]. Southward, it could occur in mangroves in [[Mon State]].<ref>{{Cite web |last=Pskhun |date=2023-12-14 |title=Species New to Science: [Herpetology • 2023] Trimeresurus ayeyarwadyensis • A New Species of Pit-viper (Serpentes: Viperidae) from the Ayeyarwady and Yangon regions in Myanmar |url=https://novataxa.blogspot.com/2023/12/trimeresurus.html |access-date=2025-10-29 |website=Species New to Science}}</ref>
== Behavior == The behavior of ''Trimeresurus ayerwadyensis'' is unknown.
== References == {{Creative Commons text attribution notice|cc=by4|url=https://zookeys.pensoft.net/articles.php?id=110422|authors=Chan, Kin Onn; Anuar, Shahrul; Sankar, Ananthanarayanan; Law, Ingg Thong; Law, Ing Sind; Shivaram, Rasu; Christian, Ching; Mulcahy, Daniel G.; Malhotra, Anita}} {{reflist}}
{{Trimeresurus}} {{Taxonbar|from=Q136773783}}
[[Category:Trimeresurus|ayerwadyensis]] [[Category:Snakes of Southeast Asia]] [[Category:Snakes of Myanmar]] [[Category:Reptiles described in 2023]]