Louse, pygmy hog sucking

Haematopinus oliveri

phylum: Arthropoda

class: Insecta

order: Anoplura

family: Haematopinidae

status: Critically endangered, IUCN

range: Bhutan, India, Nepal

Description and biology

The pygmy hog sucking louse is a parasite, or an organism that lives on or in another organism (called a host) and gets its nourishment from that host. The louse lives only on the pygmy hog, the smallest of all pig species. Because it lives on the hog's body surface, the louse is known as an ectoparasite.

Biologists (people who study living organisms) have not yet been able to collect a male louse specimen. Female pygmy hog sucking louses measure about 0.15 inch (0.38 centimeter) in length. They are wingless and have flat, leathery bodies. Their legs are strong with powerful claws for clinging to the hairs on the pygmy hog's body. These louses feed only on the hog's blood, and their mouths are specially developed for piercing and sucking.

Biologists do not know exactly how the louses reproduce. Mating seems to take place between males and females on a host hog. Females attach their eggs to the hairs on the hog's body, and the eggs hatch in about two weeks.

Habitat and current distribution

The pygmy hog sucking louse cannot survive apart from the pygmy hog. Therefore, it is found only where pygmy hogs are found. The primary habitat for these hogs is dense, tall grasslands. The greatest number of hogs is found mainly in Manas Wildlife Sanctuary and Barnadi Wildlife Sanctuary, both located in northwestern Assam (a state in far eastern India). Biologists estimate that less than 300 pygmy hogs currently exist.

History and conservation measures

The greatest threat to the pygmy hog sucking louse is the loss of its host, and the pygmy hog is one of the most endangered mammals in the world.

Hunting has reduced the number of pygmy hogs, but destruction of the animal's habitat is the main reason for its decline. The upland savannas of northern India are fertile, and farmers routinely set fires to these grassland areas to clear them to create farms. The extensive fires often kill many pygmy hogs because they cannot escape in time. Those that do escape are forced onto very small grassland areas where they are sometimes killed by unexpected fires or by hunters.

In 1985, the International Union for Conservation of Nature and Natural Resources (IUCN) placed the pygmy hog on its first list of the 12 most threatened species in the world. The following year, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) designated the Manas Wildlife Sanctuary as a World Heritage Site. In India, the pygmy hog has been granted the maximum legal protection allowed.

Despite these protective measures, pygmy hog habitat continues to be destroyed. If nothing is done to stem this destruction, the pygmy hog—and with it the pygmy hog sucking louse—will disappear.