Overview
Kitti’s Hog-nosed Bat (Craseonycteris thonglongyai), frequently celebrated as the ‘bumblebee bat,’ holds the extraordinary title of the world’s smallest mammal by skull length and body dimensions (competing with the Etruscan shrew for absolute mass). Discovered in 1973 by Thai zoologist Kitti Thonglongya, this minuscule aerial creature is the sole member of the family Craseonycteridae. Endemic to a handful of remote limestone caves in western Thailand and southeastern Myanmar, it weighs barely more than two grams and navigates dense tropical river valleys using high-frequency echolocation.
Biology and Physical Characteristics
Weighing only about 1.5 to 2 grams, Craseonycteris thonglongyai features a reddish-brown to slate-grey pelage with paler underparts. Its common name derives from its distinctive, fleshy snout with vertical, slit-like nostrils closely resembling a pig’s snout. The bat possesses relatively large, broad ears with long traguses, large eyes for a microbat, and broad, translucent wings with long tips adapted for nimble hovering flight. Uniquely, it has no external tail whatsoever, but retains a wide interfemoral membrane (uropatagium) stretched between its hind legs that aids in netting aerial prey.
Behavior and Ecology
Kitti’s hog-nosed bats roost high in deep chambers of limestone caves, hanging individually rather than in tight clusters, in colonies ranging from ten to a few hundred individuals. Highly specialized in their foraging schedule, they emerge for only about 30 to 45 minutes at dusk and another 20 minutes before dawn. Flying with agile, hovering maneuvers around the canopies of bamboo thickets and dry deciduous trees, they glean small insects off foliage and snatch tiny airborne flies using constant-frequency, high-intensity echolocation calls tuned to roughly 115 to 120 kilohertz.
Conservation and Human Impact
Assessed as Near Threatened on the IUCN Red List, Kitti’s Hog-nosed Bat is vulnerable due to its exceedingly small geographic range and reliance on highly specific cave microclimates. Historically threatened by specimen collection, tourism disturbance, religious guano harvesting, and nearby limestone quarrying for cement production, populations in Thailand are now largely protected within Sai Yok National Park. However, cave disturbance and deforestation in Myanmar continue to pose conservation challenges requiring ongoing binational habitat monitoring.
Interesting Factoid
An adult Kitti’s Hog-nosed Bat weighs only about 2 grams—less than a standard US dime or a single grape—yet it flies with astonishing agility and catches hundreds of insects during two brief 30-minute feeding windows each day.