Feb. 5 (UPI) -- Scientists have discovered a primitive arthropod species inside a pair of limestone caves on Canada's Vancouver Island.
Until deglaciation began some 18,000 years ago, the island and caves were buried beneath ice. As such, the species, Haplocampa wagnelli, presence within the caves presents two interesting possibilities.
Perhaps the cave-dwelling dipluran's discovery proves terrestrial arthropods survived in deep subterranean habitats during the Last Glacial Maximum, which peaked around 26,000 years ago. It's also possible the newly discovered species diverged from its Asian relatives and migrated to Vancouver Island during deglaciation.
Most cave-dwelling campodeid diplurans, a family of hexapods, featured an elongated body and appendages. But Haplocampa wagnelli isn't all that slender. Its antennae are only slightly elongated and its legs and abdomen are shorter and thicker than most of its relatives.
Its shape suggests the species doesn't live exclusively underground and is likely found in soil habitats above ground. And yet, its closest North American relative appears even less adapted to subterranean living.
The newly discovered species -- described this week in the journal Subterranean Biology -- is most closely related to three species, two of which are found on the other side of the Pacific, in Japan and Siberia.
Its unique similarities to both Asian and North American hexapods "suggest probable dispersal events over the Bering Land Bridge," researchers wrote.