Scientists Rediscover the Leggiest Animal on Earth
Once believed to be extinct, a rare millipede with 750 legs has been found by scientists in California.
The leggiest animal in the world, the millipede lllacme plenipes, was re-discovered several years ago in California by Paul Marek. Now, Marek and his colleagues provide further details of the surprisingly complex anatomy of this diminutive creature and its extreme rarity, limited to a handful of spots just south of San Francisco.
The most noticeable thing about millipedes are their number of legs, which line up along their body sides in synchronous "metachronal waves". The acme of legginess in millipedes is the Californian species Illacme plenipes .The females have up to an astounding 750 legs; the males only have a maximum leg count of 562. The proliferation of legs may be an adaptation for its lifestyle spent burrowing underground and enable the millipede to cling tightly to the sandstone boulders found exclusively associated with the species in its habitat.
Not only is this species the leggiest animal known on the planet, it also has surprising anatomical features: body hairs that produce silk, a jagged and scaly translucent exoskeleton, and comparatively massive antennae that are used to feel its way through the dark because it lacks eyes. Its mouth, unlike other millipedes that chew with developed grinding mouthparts, is rudimentary and fused into structures that are probably used for piercing and sucking plant or fungal tissues.
This rare and ancient-looking creature's home is California, on the outskirts of Silicon Valley. The species is exceedingly scarce and limited to just a single tiny area near San Juan Bautista. Based on the known environmental conditions where it lives, the species' probable distribution elsewhere in California was inferred. Yet still restricted to a small geographical range, the analysis indicated other areas of suitability limited to the terrestrial areas on the edge of Monterey Bay eastward to San Juan Bautista and throughout the Salinas Valley.