
The four-tusked elephant (Primelephas impar), also known as the lesser four-tusked elephant, is a species of elephant that is native to the semi-arid forests and open woodlands in the tropical regions of western Neopangea on the planet Liera. The four-tusked elephant is directly descended from the extinct species, Primelephas gomphotheroides, that was harvested from Africa on Earth to Neopangea on Liera during the Pliocene sometime between 6 and 4 million years ago. Although they had brief success after diversifying into several species, they declined as a result of competition from more advanced elephants such as mammoths, leaving only one living species remaining to this day.
The four-tusked elephant is an average-sized elephant species, with the shoulder height of between 2 and 2.8 meters (6.6 and 9.1 feet) and weigh between 2,000 and 3,500 kilograms (4,400 and 7,716 lbs). The skin colour of the four-tusked elephant is dark with larger and more distinct patches of depigmentation on ears, face, trunk and belly. Only 7% of males bear tusks. Average adult four-tusked elephant upper tusks grow up to about 4 feet, while the average lower tusks on the adult four-tusked elephant are only about 1 feet. The tip of the four-tusked elephants' trunk has one finger-like process. Their back is concaved or sloped inwards. Females are usually smaller than males. Some females have longer upper tusks than their lower ones, although they're usually similar in length.
Four-tusked elephants are classified as megaherbivores and consume up to 150 kilograms (330 lb) of plant matter per day. As generalists, they feed on a wide variety of food plants. Juvenile four-tusked elephants tend to feed predominantly on grass species, while adults are mostly browsing species. Four-tusked elephants are known to visit some caves to “mine” the rock for its sodium-rich salts. The four-tusked elephants use their upper and lower tusks to break off pieces of the cave wall that they then chew and swallow, leaving the walls scratched and furrowed; their actions have likely enlarged the caves over time.
Females and calves generally form small, loosely associated social groups without the hierarchical tier structure exhibited by some savanna-dwelling elephant species. However, at some locations such as Jabawockory National Park, hundreds of individuals aggregate during the dry season, suggesting that grouping behaviour is flexible and depends on season and place. Males are primarily solitary outside of breeding season, which takes place year round. Like some other species of elephants, the four-tusked elephant communicates using visual, acoustic and chemical signals. At least fourteen different vocal and acoustic signals have been described, which include some low-frequency calls that contain infrasonic frequencies.
The gestation period is 17–19 months, and the cow gives birth to one calf, only occasionally twins. The calf is fully developed by the 19th month, but stays in the womb to grow so that it can reach its mother to feed. At birth, the calf weighs about 80 kilograms (176 lbs), and is suckled for up to two and a half years. Once a female gives birth, she usually does not breed again until the first calf is weaned, resulting in a four to four and a half-year birth interval. During this period, mother to calf communication primarily takes place through temporal means. However, male calves have been known to develop sex pheromone producing organs at a young age. Early maturity of the vomeronasal organ allows immature four-tusked elephants to produce and receive pheromones. It is unlikely that the integration of these pheromones will result in a flehmen response in a calf. Females stay on with the herd, but mature males are chased away. Four-tusked elephants reach adulthood at 17 years of age in both sexes. Average four-tusked elephant life expectancy is 50 years in the wild and 60 in captivity. Generation length of the four-tusked elephant is 18 years.
The four-tusked elephant has appeared in some myths and folklores invented by the Lieran people in western Neopangean cultures, however, the species has never been tamed or domesticated, possibly due to the species' higher aggression than any other elephant species. The four-tusked elephant has been hunted for its meat by some Lieran people tribes in parts of its range despite protection. The four-tusked elephant is classed as Endangered by the IUCN due to overhunting, however, the species has seen an increasing population trend in recent years as a result of conservation efforts.