PYGMY HOG SUCKING LOUSE ENDANGERED Haematopinus oliveri Mishra and Singh, 1978 Phylum ARTHROPODA Order ANOPLURA Class INSECTA Family HAEMATOPINIDAE SUMMARY The Pygmy Hog Sucking Louse is a blood-sucking ectoparasite known only from the Pygmy Hog ( Sus salvanius), an endangered species probably restricted to north-west Assam in northern India. Both the hog and its attendant louse are threatened by destruction of thatch-scrub savanna. DESCRIPTION The Anoplura are blood-sucking ectoparasites of mammals; they are wingless and cannot live independently of the host at any stage of the life-cycle. The eyes are reduced or absent, and the mouthparts highly modified for piercing and sucking. The body is dorsoventrally flattened with a leathery integument, and the legs are strongly developed with powerful claws for attachment to the host's hairs (12). Haematoplnus oliveri is a parasite of the Pygmy Hog ( Sus salvanius . The female louse is 39 to tt2 mm in total length; the male is unknown. The species has been described in some detail and differs from the other six species of Haematoplnus by a combination of the absence of paratergite II, the shape of the thoracic sternal plate and the relatively short head (6,15,16). DISTRIBUTION The seven species in the genus Haematoplnus infest wild pigs from Africa and Europe right across the Orient to the Philippines (15,16). The Pygmy Hog was formerly found in southern Nepal, Sikkim, north-west Assam, the foothills of Meghalaya, northern Bangladesh and south-east Assam. It is now extinct in most of this range and probably restricted to small, endangered populations in north-west Assam, India Cf, 8,9, 10, 1 1). POPULATION Unknown. The only specimens collected are three females (holotype and two paratypes) and one associated nymph, all taken from a Pygmy Hog in Darrang, north-west Assam in 1977 (6). In louse populations, as in many other parasites, most individuals are on a few animals, whilst most hosts have few or no parasites. Elimination of very few hosts from a population may, therefore, lead to virtual or complete elimination of lice from that host population (3). The Pygmy Hog was at one time feared extinct but reappeared in 1971 near Barnadi. That hog population is now virtually extirpated and the only certainly known surviving population is in Manas National Park and certain of its buffer Reserve Forests (8,9,10,11). The population there is believed to be only a few hundred individuals, but may be considerably less. HABITAT AND ECOLOGY Anoplurans are generally very host-specific. Close physiological relationships between the parasite and the host's blood characters are important (1), but this is only one of a variety of interacting components, including host hair type, skin microclimate and host ecology (3,5). The majority of Anoplura carry symbiotic bacteria which are essential in providing B group vitamins (13,17). The lethal effect of abnormal host-blood on Anoplura may result from the death of these bacteria (1,12), or from the accumulation of crystalline blood chemicals which rupture the midgut (2,7). Details of the biology of the louse are not known, but in common with other Anoplura it certainly feeds solely on blood and cannot survive without the host (17). Mating occurs on the host, and the eggs are cemented to host hairs, probably hatching within two weeks (12). The habitat of the Pygmy Hog is primarily unburnt thatch-scrub savanna, composed of mixed scrub and tall grasses (f8,9,10ll). 365