November 14, 2012
Rediscovering The Most-Legged Animal On Earth
Lee Rannals for redOrbit.com — Your Universe Online
[ Watch the Video: Leggiest Animal On Earth ]
Paul Marek and colleagues provided details of the millipede lllacme plenipes' complex anatomy and its rarity in the journal ZooKeys.
The female lllacme plenipes have up to 750 legs, compared to the males who only have a maximum of 562 legs.
The scientists said the proliferation of legs may be an adaption to its lifestyle spent burrowing underground or to enable it to cling to the sandstone boulders found near the species habitat.
"This relict species is the only representative of its family in the Western Hemisphere. Its closest presumed relative, Nematozonium filum, lives in South Africa and this early relationship was established more than 200 million years ago when the continents coalesced in the landmass Pangaea," the lead author Dr. Paul Marek, from the University of Arizona, said in a statement.
This species not only has an extraordinary number of legs, but it also has body hairs that produce silk, a jagged and scaly translucent exoskeleton, and comparatively massive antennae that are used to help it find its way through the dirt.
lllacme plenipes' mouth is unlike other millipedes that chew with developed grinding mouthparts. It is rudimentary and fused into structures the scientists believe are used for piercing and sucking plant or fungal tissues.
The species lives in a tiny area near San Juan Bautista, just east of the San Andreas Fault. The analysis of the animal indicates other areas of suitability limited to the terrestrial areas on the edge of Monterey Bay eastward to San Jaun Bautista and throughout the Salinas Valley.
The area is unique because it has a thick layer of fog that accumulates like soup in a deep bowl. This feature, alongside the species' unique set of features in its habitat, make this area a special place deserving of attention as the home of this rare millipede.
lllacme plenipes were thought to be extinct over the past 80 years, and Marek said that rediscovering it "was wonderful."
“To tell you the truth, and this is the experience every time I find a species I´ve never seen before, it was an exhilarating experience," Marek told Scientific American. "Even when reading about other entomological discoveries (whether it be the Lord Howe Island stick insect or bioluminescent cockroaches) it´s exciting to think about all the fantastic and diverse life forms that live with us on the planet.”
The team was able to help distinguish it from other millipede species by taking a special look into its genitals.
“For this relict species in particular, and especially since there´s nothing like it in the Western Hemisphere, [distinguishing the species] is pretty straightforward. It´s so completely different, anatomically, from anything else in the area,” he told Scientific American. “For questions about species that are more closely related to one another, millipede taxonomists use the anatomical differences in the genitalia under the lock-and-key hypothesis — in a crude way, ℠the idea that a lock from one species cannot be opened with a key from another´.”
Due to lower population numbers, and its limited habitat, the future of the millipede species is uncertain. Marek said exploitation as a result of over-collecting is something they tried to avoid while gathering information about them.
“The idea with conservation is to preserve as much biological diversity as possible, and not only is this species so different than anything else in the area, the habitat that it lives in is filled with so many different and unique species — things that we know so little about," he told Scientific American.
He said many species found in the lllacme plenipes' habitat are unlike any other found on Earth, including everything from beetles and salamanders to oak trees and mosses.