Thoroughly urban Millie – millipede, that is

A newly described species of millipede is found only within the city limits of Launceston, located on the northern coast of the main island of Tasmania, challenging common assumptions about the suitability of cities for unusual wildlife species.

Tasmaniosoma anubis is about 1 centimeter long, with a pale, yellowish-brown body and a darker, reddish-brown head, and it favors piles of bark litter at the base of eucalyptus trees, millipede specialist Robert Mesibov reported last week in the journal ZooKeys.

Two local naturalists, Wade and Lisa Clarkson, first found the millipede in Launceston’s largest urban reserve, the 440-acre Trevallyn Nature Recreation Area. The type specimen, meaning the individual upon which the scientific description of the organism is based, was collected from a stand of white-barked Eucalyptus viminalis trees next to a parking lot.

T. anubis is one of 22 described species in the genus Tasmaniosoma, which is endemic to Tasmania – that is, the genus is found only on this island to the south of Australia.

The species name refers to the jackal-headed Egyptian god Anubis, but the millipede’s connection is considerably baser: projections at the top of the male’s genitalia look remarkably like the snout and ears of a jackal. Many millipede species are difficult to identify at a glance and can only be distinguished by peering at their genitals or counting the number of bristle-like setae on various parts of their bodies, so let’s not begrudge millipede people getting their kicks where they can.

The new millipede is common in several Launceston city parks, but is absent from eucalyptus groves outside the city. Altogether the species has a known range of less than 12 square kilometers. All of the locations where it has been found are within about 1.5 kilometers of the South Esk River, which joins with the Tamar River within the city of Launceston at a location called Cataract Gorge.

Many species of Tasmaniosoma have relatively small ranges, and T. anubis is easy to find in Launceston parks, where it coexists with introduced millipedes and another species of Tasmaniosoma. So despite its small range, the millipede does not appear to be a threatened species.

But Mesibov theorizes that it was more widespread prior to the 19th century, when the area’s eucalyptus woodlands began to be degraded by sheep grazing and cleared for residential development of Launceston. The combination of these forces likely constrained the millipede to the urban parks where it is found today.

Usually we think of cities as being home to a degraded suite of wildlife – rats, starlings, crows – or, at best, to enterprising interlopers like coyotes. So it’s strange to imagine that a city could be a refugium for endemic species.

But scientists have previously described a land snail, a pseudoscorpion, and a spider believed to exist only in the Cataract Gorge area. Perhaps city parks elsewhere in the world hold yet-to-be-discovered urban endemics, too.

Sure, most such species are likely to be small creepy-crawly types, like the millipede. But maybe they can help remind us not to count our own habitat out. – Sarah DeWeerdt | 24 March 2015

Source: Mesibov R. 2015 Three new species of Tasmaniosoma Verhoeff, 1936 (Diplopoda, Polydesmida, Dalodesmidae) from northeast Tasmania, Australia. Zookeys DOI:10.3897/zookeys.488.9460

Header image: A male and two female specimens of Tasmaniosoma anubis. Credit: Dr. Robert Mesibov.