The chiroptera (Na'vi name: narluk) is an efficient aerial predator that is well adapted to the cave environments in which it roosts. Entirely blind, it has evolved acute hearing that facilitates an echolocation sense, which is used for navigation and to locate its mostly aerial prey.
Anatomy[]
The chiroptera has an eyeless and smoothly featured head with a powerful, beak-like jaw. The head is crowned with a pair of long, supple, parietal ears above a smaller pair of lateral ears and short, feathery antenna protrude from the front of the skull.
Its muscular torso has four slender limbs, webbed with leathery membranes that stretch between these appendages, each terminating in sharply hooked digits. Distinct patterning on its wings and head contrast with a typically paler lower body. An adult chiroptera wingspan can be up to ten meters.
With their light, powerful wings, chiroptera are capable of sustained periods of flight and hovering. Each wing-limb possessing[sic] a scythe-like digit that is used to cling to rocky surfaces and for hunting. Any prey it disables is dispatched with its strong, sharp, beak which can cut through thick bone and carapace.
Behavior[]
Emitting multi-frequency "barks" from its larynx and listening for echoes with a series of complex, cochlear-like chambers within its skull, its echolocation sense is extremely precise, especially in its preferred cave environment. The subsonic frequencies within a chiroptera bark can also stun and confuse potential prey.
The chiroptera make their nests in deep cave systems away from sunlight, and roost hanging from cave ceilings where they sleep throughout daylight hours. An egg-laying animal, its egg sacks - or ootheca - protect hundreds of embryos, which hatch into swarming juveniles.
These immature hatchlings are far more active than adults of the species, maintaining a constant presence in the cave nest. Largely defenseless, hatchlings are timid and screech their alarm at any threat to their environment.
Due to high attrition to other predators, few hatchlings survive until adulthood. These will go on to form their own small, social colonies in neighboring caves, sometimes cohabiting with echo stalker packs for mutual defense of their young.
There are three clear categories of chiroptera within a colony. The first category is the largest and is comprised of mature breeding males, and the matriarchs, who are elder females. Several matriarchs may inhabit the same nesting cave.
The next category is smaller adult males who are not yet part of a breeding flock of chiroptera. Lastly, the final category is made up of chiroptera hatchlings that have recently emerged from their eggs.
When an aerial threat enters a chiroptera nest, the hatchlings emit a shrieking alarm, but do not engage. The medium-sized males instinctively create a swarm to protect the matriarch as she dives down to monitor the threat. Meanwhile, the larger males immediately engage aerial threats, as the matriarch mostly keeps her distance behind the swarm. Together, the colony creates a highly effective security system to protect their nest from predators.
Na'vi Culture[]
Na'vi largely avoid nesting caves, they are extremely territorial, and their screech is known to instill terror in even the heartiest hunter, likely due to the psychological effect of infrasound. The rarely collected chiroptera egg can be used for cooking, but its scarcity and unusual aroma make it an unusual delicacy.