Order Polyxenida

Dorsal (left) and ventral (right) views of Propolyxenus forsteri.

The tiny polyxenidans, or 'bristle millipedes', are hard to confuse with any other group of animals. They have tufts of bristles on their sides, rows or clumps of bristles across the back of each segment, and some species have two long brushes of bristles at the rear end. Adults reach 3-4 mm in length in Tasmanian species and have 13 pairs of legs. Polyxenidans seem to be most abundant in dry forest and heathland at low elevations in eastern and northern Tasmania, but specimens have also been recovered from leaf litter in rainforest near Weldborough, at ca. 650 m. They are more typically found in small groups in relatively dry shelters, such as cavities under loose bark.

Polyxenidans were first collected in Tasmania in the 1980s. An extremely elusive species from northwest Tasmania (above) has been tentatively identified by a Polyxenida expert as Propolyxenus forsteri Condé, 1951, which was first described from New Zealand. In early 2008, visiting specialist Megan Short (Deakin University) collected Phryssonotus novaehollandiae (Silvestri, 1923) (below) near Bridport, and an undescribed species of Unixenus near Launceston. P. novaehollandiae may be Australia's most widely distributed millipede; it has so far also been found in Queensland, New South Wales, Victoria, South Australia and Western Australia.

Dorsal (left) and ventral (right) views of Phryssonotus novaehollandiae.

Localities for Propolyxenus forsteri (blue), Phryssonotus novaehollandiae (red) and unidentified polyxenidans (gray).  Scale bar = 100 km.
For an interactive map with more up-to-date localities, go to the mapper page.

More information:
 
Taxonomy - Short & Huynh (2006)
Biology - Hopkin & Read (1992)
Distribution, conservation and general - Mesibov (2001)