Myron richardsonii GRAY, 1849
Can you confirm these amateur observations of Myron richardsonii?
|Higher Taxa||Homalopsidae, Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Common Names||E: Richardson’s mangrove snake|
|Synonym||Myron richardsonii GRAY 1849: 70|
Myron Richardsonii — GÜNTHER 1859: 232
Neospades kentii DE VIS 1889
Myron richardsonii — LIDTH DE JEUDE 1911: 279
Myron richardsonii — COGGER 1983: 213
Myron richardsonii — COGGER 2000: 625
Myron richardsonii — MURPHY 2011
Myron richardsonii — MURPHY & VORIS 2014: 30
Myron richardsonii — WALLACH et al. 2014: 467
|Distribution||Indonesia (Aru Islands, Irian Jaya), Australia|
Australia (Northern Territory, Western Australia)
Type locality: "N.-Western Australia", restricted to Buffalo Creek, Northern Territory, Australia (about 12°40'S and 131°29'E) by MURPHY 2011.
|Types||Holotype: BMNH 19184.108.40.206|
Holotype: QM J681, from Cambridge Gulf, W. A. [Neospades kentii].
|Diagnosis||Diagnosis (genus): Head distinct from neck; parietals entire; internasal usually single and separating nasals; loreal present; dorsal scales weekly keeled on posterior of body, and in 19–21 rows at mid body, usually reduced to 17 near the vent; ventrals broad; upper labials 2–3 or 2–4 contact loreal; upper labial 4 enters the orbit; enlarged occipital scales present; three pairs of chin shields present with the middle pair the longest. Note that this genus is gender neutral [from MURPHY 2011]. See MURPHY & VORIS 2014: 30 for an alternative diagnosis.|
Diagnosis (species): A Myron with 21 scale rows on the neck and at mid body that are reduced to 17 or 19 rows near the vent; the posterior dorsal scale rows above row 6 are weakly keeled; two preocular scales; upper labials usually number 8 or 9; plate-like occipital scales located on the posterior edge of the parietals; 8 to 10 upper labials; and a dorsal pattern of blotches that number 35 to 48. The presence of 21 scale rows and two preoculars will distinguish it from M. resetari. The 8 to 10 upper labials and blotched pattern will separate it from M. karnsi which is melanistic with narrow yellow crossbands.
Eight males had 131–137 ventrals (x=133.8, sd=1.80) and 33–39 subcaudals (x=35.6, sd=1.76). Six females had 131–139 ventrals (x=135.5, sd=3.62) and five females had 30–34 subcaudals (x= 31.6, sd=1.82). While the ventral counts show no sexual dimorphism, the subcaudal counts based on this limited sample size most likely do.
Key to the Australian species of Myron:
resetari: One preocular scale on each side; fifth supralabial the largest
richardsonii: Two preocular scales on each side; sixth or seventh supralabial the largest (from Cogger 2014: 846).
|Comment||Synonymy after COGGER 1983.|
Habitat: estuarine to marine. This is a sea snake.
Type species: Myron richardsonii GRAY 1849 is the type species of the genus Myron GRAY 1849.