Hispid hare
Chitwan National Park, Nepal
Conservation status
Endangered  (IUCN 3.1)[1]
CITES Appendix I (CITES)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Lagomorpha
Family:	Leporidae
Genus:	Caprolagus Blyth, 1845
Species:	C. hispidus
Binomial name
Caprolagus hispidus (J. T. Pearson in Horsfield, 1840)
Hispid hare range
Synonyms[2]
Lepus hispidus J. T. Pearson in Horsfield, 1840

The hispid hare (Caprolagus hispidus), also known as the Assam rabbit and bristly rabbit, is a species of rabbit native to South Asia. It is the only species in the genus Caprolagus. Its historic range extended along the southern foothills of the Himalayas. Once thought extinct, it was rediscovered in Assam in 1971 and has been found in isolated populations across India, Nepal, and Bangladesh. Today, its habitat is highly fragmented, and the region it occupies is estimated at less than 500 km² (190 sq mi) extending over an area of 5,000 to 20,000 km² (1,900 to 7,700 sq mi). Populations experienced a continuing decline due to loss of suitable habitat via increasing agriculture, flood control, and human development. It has been listed as Endangered on the IUCN Red List since 1986.^[1]

The hispid hare was placed in the genus Lepus, the hares, on its first description by the British surgeon John Thomas Pearson in 1839, where it was given the scientific name Lepus hispidus. This description was first published in the Calcutta Sporting Magazine, but the first formal account was published by Thomas Horsfield a year later in the Proceedings of the Zoological Society.^[3] Pearson noted that the ears of the hispid hare were so short as not to extend past the fur on its head, but later authors assumed this to be a mistake. The species name hispidus, as well as the common name "hispid hare", refers to the coarseness of the fur,^[4] as the term describes something as being rough or covered in stiff hairs.^[5] English zoologist Edward Blyth gave the hispid hare a distinct genus, Caprolagus, in 1845 due to its unusual morphology, though he did not provide a reasoning for the name chosen. He noted in particular the unusually rough fur, large and robust skull, diminished eyes and whiskers, strong claws, and equally-proportioned limbs.^[4] Later studies in the 21st century confirmed its place as the only species within its genus;^[6] the closely related^[7] extinct species †Pliosiwalagus sivalensis was once considered to be a member of Caprolagus, but was reclassified in 2002.^[8] The type specimen of the hispid hare was taken from the "base of the Boutan [= Bhutan] mountains" in Assam, India, and was described by Blyth in his 1845 description of the new genus,^[9] but it is unclear if this specimen exists in any collection today.^[10]

The hispid hare's coarse fur coat along its back gives it the name "bristly rabbit". In Assamese, it is known as the khargorkata or ha ha pahoo; in Nepali, it is called the jungli karayo.^[6]

No fossils of the hispid hare exist, though several fossils have been found that may be broadly assigned to Caprolagus, indicating that members of the genus may have existed in regions as distant as Indonesia at one point.^[6] Fossils of one extinct species, Caprolagus lapis, may date back 3.6 million years.^[11]

The following cladogram shows the relationships between Caprolagus, other rabbits, and hares, based on a phylogenetic tree from Leandro Iraçabal and colleagues published in 2024:^[12]

The hispid hare has a harsh and bristly coat. The coat is dark brown on the back due to a mixture of black and brown hairs; brown on the chest and whitish on the abdomen. The tail is brown and about 30 mm (1.2 in) long. In body weight males range from 1,810 to 2,610 g (64 to 92 oz) with a mean of 2,248 g (79.3 oz). Females weigh on average 2,518 g (88.8 oz); a heavily pregnant female weighing 3,210 g (113 oz) was included in this statistical mean weight.^[13]

The frontal bones are very wide. The occipito-nasal length generally exceeds 85 mm (3.3 in). There is no clear notch in front of postorbital processes.^[14]

In average, this hare is 476 mm (18.7 in) long from head to tail.^[15]

The historical range of the hispid hare extended from Uttar Pradesh through southern Nepal, the northern region of West Bengal to Assam and into Bangladesh. Today, its distribution is sporadic in Bangladesh, India, Nepal and Bhutan. It inhabits tracts of early successional tall grasslands and takes refuge in marshy areas or grasses adjacent to river banks during the dry season, when these areas are susceptible to burning.^[13] The population in the extensive grasslands of Shuklaphanta National Park may be of international significance.^[16]

Prior to its rediscovery in Bornadi Wildlife Sanctuary in 1971, the species was thought to be extinct. Sightings of the rabbit have occurred sporadically since then across its distribution, though the population is in decline due to habitat loss.^[17] In January 2016, a hispid hare was recorded in Chitwan National Park for the first time since 1984.^[18]

The hispid hare is most active at dawn and dusk. The limited information available on reproduction indicates that its average litter size is small.^[13]

Grassland habitats of the hispid hare are threatened due to overgrazing by cattle.^[19]