Craspedocephalus trigonocephalus is a
sexually dimorphic, mid-sized, cylindrical species. These snakes measure 20–25 cm (7.9–9.8 in) at birth, and males grow to a maximum total length of 60–75 cm (24–30 in). The neck is distinct from the flattened, triangular head. There is a
loreal pit on each side of the head. Mid-sized eyes and a short, rounded, broad
snout are present. The males are considerably smaller than females, which can grow up to 130 cm (51 in) in total length. The ground color of the snake is variable and
cryptic. Typically, it is a green snake with a black
variegated pattern, and a black
temporal line is usually present. The wet zone snakes have these black patterns more clearly marked. The
vertebral area has a tinge of yellow. The tail is black. The
ventral scales are light greenish-yellow or may even be grey. Some snakes have only the black temporal line and the black tail, with the rest of the body being green. In addition, males tend to have a blue coloration, whereas the females are predominantly green. These are bulky snakes with
prehensile, short tails, suiting their
arboreal lifestyle.[4][5]
head details.
Reproduction
These are
viviparous snakes. About five to 25 young are produced at once.[4][5]
These snakes have two or three large supra
ocular scales, and their
nasal scales are partially divided into two or may not be divided. They have three preoculars, two or three postoculars, 9–10
supralabial scales, three or four
infralabials, and 142–160
ventrals; The
anal scale is not divided; their 53–69
subcaudals are divided. At midbody, the 17–19 rows of
dorsal scales may or may not have
keels. Most head shields are small and smooth.[6]
Common names
Common names include: Sri Lankan green pit viper,[7] Sri Lankan pit viper,[8]pala polonga (පළා පොළඟා), and green pit viper.[9][10]
Geographic range
It is an endemic species to Sri Lanka and widely distributed in all three
climatic zones of the island, except higher hills and
arid zones, while relatively more common in wet zone
grasslands and
rain forest areas and occasionally in
plantations of
cardamom,
cocoa,
coffee, and
tea, from the lower altitudes from 153 to 1,800 m (502 to 5,906 ft).[11] The
type locality given is "l'île S.-Eustache" (Sri Lanka).[1][12][13]
Behavior
It is
arboreal and
nocturnal, occasionally descending to the ground in search of food such as lizards, frogs, small mammals, and birds. This sluggish
pit viper is usually encountered on low shrubs during morning hours, but it mostly occupies in grasslands and rain forests. In mornings, it is seen to stay on top of trees to obtain sun rays to heat its body. It uses its tail to hold on to a tree branch. This is not a particularly defensive species, but if agitated, it will vibrate its tail tip, form a sinuous loop with the fore body, and lash and attempt to bite, seldom with a hissing sound. It produces live young mostly during June and July.[14][15]
^
abMcDiarmid RW,
Campbell JA, Touré T. 1999. Snake Species of the World: A Taxonomic and Geographic Reference, Volume 1. Herpetologists' League. 511 pp.
ISBN1-893777-00-6 (series).
ISBN1-893777-01-4 (volume).
^
abcMalhotra, Anita & Thorpe, Roger S. (2004). "A phylogeny of four mitochondrial gene regions suggests a revised taxonomy for Asian pitvipers (Trimeresurus and Ovophis)". Molecular Phylogenetics and Evolution. 32 (1): 83–100.
doi:
10.1016/j.ympev.2004.02.008.
PMID15186799.
^
abGuo, P.; Jadin, R.C. & Malhotra, Anita (2009). "An investigation of the cranial evolution of Asian pitvipers (Serpentes: Crotalinae), with comments on the phylogenetic position of Peltopelor macrolepis". Acta Zoologica. 91 (4): 402–407.
doi:
10.1111/j.1463-6395.2009.00413.x.
^Sonnini de Manoncourt, C.S. &
Latreille, P.A. (1801). Histoire Naturelle des Reptiles, avec Figures Dessinees d'Apres Nature (in French). Paris, Librairie encyclopédique de Roret. p. 332.
^Gumprecht A, Tillack F,
Orlov NL,
Captain A, Ryabov S. 2004. Asian Pitvipers. Geitje Books. Berlin. 1st Edition. 368 pp.
ISBN3-937975-00-4.
^Mehrtens JM. 1987. Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp.
ISBN0-8069-6460-X.
^Boulenger, G.A. (1896). Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the...Viperidæ. London: Trustees of the British Museum (Natural History). (Taylor and Francis, Printers.). pp. 559–560.
Pulihansu Book of Snakes, 2009. Donndorff, Johann August. 1798. Amphibiologische und Ichthyologische Beyträge zur XIII. Ausgabe des Linneischen Natursystems. Dritter Band. Amphibien und Fische. Weidmannschen Buchhandlung. Leipzig. vi + 980 pp. (Coluber trigonocephalus, p. 203.)
Sonnini, C.N., and
Latreille, P.A. 1801. Histoire Naturelle des Reptiles, avec figures dessinées d'après nature; Tome III. Seconde Partie. Serpens. Crapelet. Paris. 335 pp. (Vipera trigonocephala, pp. 332–333.)