Fig. 4.72 Calloselasma rhodostoma

Distribution

Thailand to southern Vietnam, far northwest Malaysia, Java and offshore islands (isolated occurrence in the south of Sumatra not conclusively proven). See link "Distribution" at the top of the page for detailed information.

  Map 57 Calloselasma rhodostoma

Biology

Sturdy, short body with tapered head clearly distinct from the body. Appearance as for Agkistrodon spp. Rarely more than 1 m long. Basic colouring in shades of grey or brown, with characteristic dark triangles or rhombi that originate from either side of the spine and cover the upper half of the body.

Live in the most varied habitats in the lowlands, where they are also commonly found in rubber plantations, but can also be found up to an altitude of 2,000 m. Predominantly nocturnal, with a seasonal peak in activity during the monsoon rains. During the dry season they have been known to enter houses in search of damp recesses.

If irritated, can strike aggressively and repeatedly.

Risk

Fatalities rare. Even without antivenom treatment the mortality in Thailand is not more than approx. 1–2% (Reid et al. 1963). Nonetheless it must be emphasised that Calloselasma is one of the main causes of snakebite envenoming in Southeast Asia. The consequences of a bite are often a lengthy healing process (necroses), at times with lasting damage (deformed limbs).

Bites mainly occur while the victim is working (particularly in rubber plantations) or around dwellings. More rarely bites may also occur inside dwellings in rural regions.

Literature (biological)

Cox 1991, Deuve 1970, Gloyd and Conant 1989, Gumprecht et al. 2004, Keegan et al. 1965, Liat 1979, 1990, Saint Girons 1972, Tweedie 1983