Varanus indicus

The mangrove monitor, mangrove goanna, or Western Pacific monitor lizard (Varanus indicus) is a member of the monitor lizard family with a large distribution from northern Australia and New Guinea to the Moluccas, Solomon Islands, Marshall Islands, Caroline Islands, and Mariana Islands. It grows to lengths of 3.5 to 4 ft (1.1 to 1.2 m). The mangrove monitor was first described by the French herpetologist François Marie Daudin in 1802. Daudin's original holotype of a subadult specimen was collected on Ambon, Indonesia, and has since disappeared from the museum in Paris. Daudin's original name for the species was Tupinambis indicus, an appellation it would carry for 100 years until being renamed as a Varanus. The generic name Varanus is derived from the Arabic word waral (ورل), which translates to English as 'monitor.' Its specific name, indicus, is Latin for the country of India, but in this instance it relates to Indonesia or the East Indies, where the animal was first described. Due to its large geographic range, V. indicus is considered a cryptic species complex of at least four species: Varanus indicus, Varanus doreanus,Varanus spinulosus, and Varanus jobiensis. More research is being done on possible future species within this complex, not surprisingly, since it has had over 25 different scientific names since it was first described. The mangrove monitor's range extends throughout northern Australia, New Guinea, the Solomon Islands, the Marshall Islands, the Caroline Islands, and the Mariana Islands, where it inhabits damp forests near coastal rivers, mangroves, and permanent inland lakes. It also occurs on the Moluccan islands of Morotai, Ternate, Halmahera, Obi, Buru, Ambon, Haruku, and Seram. Within this range of thousands of miles across hundreds of islands are large variations in size, pattern, and scalation. The monitors have also been introduced to Japan since the 1940s. Like the introduction to Japan, some herpetologists believe this animal's dispersal from the East Indies to smaller Pacific islands was facilitated by Polynesians to provide a meat supply. However, other scientists maintain this is not likely, as the monitors would compete with man for food, grow slowly, and yield little meat. The monitor's body is dark green or black in color and covered with golden-yellow spots, with light coloration on the top of its head and a solid, cream-colored belly lacking dark markings. It has a distinct dark purple tongue and serrated teeth. The mangrove monitor attains different sizes in different parts of its range, but seldom if ever exceeds 1.3 m in total length. Australian herpetologist Harold Cogger gives a total length of 100 cm for Australian specimens. The tail is almost twice the length of the body and laterally compressed to aid in swimming. Like the rest of the lizard's body, it is covered with small, oval, keeled scales. This monitor has the ability to increase the size of its mouth by spreading the hyoid apparatus and dropping the lower jaw to eat large prey, a process similar in appearance to that of snakes, although the jaw of the mangrove monitor remains rigid. The mangrove monitor possesses a Jacobson's organ, which it uses to detect prey, sticking its tongue out to gather scents and touching it to the opening of the organ when the tongue is retracted. The mangrove monitor is one of only two species of monitor lizards, the other being V. semiremex, that possess salt-excreting nasal glands, which enable them to survive in saltwater conditions and to consume marine prey. The presence of this gland probably enabled the monitors to reach new islands and aid in its dispersal throughout the Pacific.