Camptoceras austeni

Camptoceras austeni has a tall, thin shell measuring about 3.75 mm (0.148 in) in height and 1 mm (0.039 in) in diameter. The oval-shaped opening of the shell, called the aperture, measures 1.6 by 0.9 mm (0.063 by 0.035 in) in height and width, respectively. The original specimen described by Blanford had 2.5 whorls, or revolutions of the shell. However, he speculated that it was not fully grown.^[2] The whorls are not fused, instead being separated by a deep channel.^[7]

This species is much smaller than its close relative Camptoceras terebra. Additionally, it may be distinguished by fewer revolutions of the shell, called whorls, as well as the rounder aperture.^[2]

Information about this species' distribution, habitat, and ecology is very limited. Camptoceras austeni is only known from the Mymensing District in Bangladesh, though its range may extend to neighboring countries including India, Myanmar, Nepal, and Bhutan.^[1] At the time of description, the species was considered rare, and only 5 specimens were discovered.^[2] In subsequent years, the species has only ever been found at its type locality, or the area from which it was originally collected. This location may be impacted by pollution and sedimentation from the developed areas surrounding it.^[1]

Like others in the superorder Hygrophila, this species may be a detritivore, feeding on periphyton such as algae and bacteria.^[3] In dry conditions, this species may form a protective barrier known as an epiphragm, which covers the shell opening and keeps the animal moist.^[7] It may be found in freshwater wetlands, rivers, and streams, where it clings to vegetation.^[3]