Komodo Dragon

Varanus komodoensis

Komodo Dragon (Varanus komodoensis) is a species in the genus Varanus, family Varanidae, order Squamata.

Scientific classification

Description

The Komodo dragon is the largest living lizard, reaching about three metres and 70–90 kilograms. It has a heavy build, powerful limbs, a long muscular tail, and serrated, laterally compressed teeth resembling those of a shark.

Prey is killed by a combination of trauma and blood loss. Komodo dragons possess venom glands in the lower jaw secreting proteins that lower blood pressure and interfere with clotting; the older story that septic oral bacteria were responsible has not held up.

Distribution

Endemic to a handful of Indonesian islands — Komodo, Rinca, Flores, Gili Motang and formerly Padar. It is the classic case of island gigantism among reptiles, though the picture is complicated by fossil evidence of comparably large varanids on mainland Australia.

Biology

Adults are apex predators taking deer, pigs, water buffalo and carrion; juveniles are arboreal, which keeps them away from cannibalistic adults, and often roll in faecal matter as a deterrent.

Females are capable of facultative parthenogenesis. Because reptiles use ZW sex determination, parthenogenetic clutches produce only males — which, for an isolated female colonising a new island, is a route to founding a population.

Conservation

Endangered, with a small total range, low numbers, and rising sea levels projected to reduce the available lowland habitat further.

References

• Fry, B. G. et al. (2009). A central role for venom in predation by Varanus komodoensis. PNAS 106.
• Jessop, T. et al. (2021). Varanus komodoensis. IUCN Red List assessment 22884.