Bornean Keeled Green Pit Viper - Tropidolaemus subannulatus | ©Bernard Dupont (Gunung Mulu NP, Sarawak, Malaysia)
Tropidolaemus subannulatus (Viperidae), better known as Bornean Keeled Green Pit Viper, and North Philippine Temple Pitviper, is a venomous snake, with heat-sensing pits on the sides of the head.
It is exclusively arboreal, occurring in Borneo, Sulawesi and many islands of the southern Philippines, however it is clear that the populations in the Philippines and Sulawesi are different species. Thus, Tropidolaemus subannulatus should really be considered as endemic to Borneo.
Juveniles and adult males have a vibrant green upperside and yellowish green belly, patterned with numerous thin, pale bicolored bars. Adult females tend to have a complex pattern comprising a ground colour of cream, with broken bluish, greenish or turquoise bands, and a thick stripe of the same colour on the sides of the head.