Introduction

Symphyla are small, blind, fast-running multipedes which can be very abundant in soil and forest litter. They are generally white, but dark-coloured gut contents can often be seen through the body wall. Not much is known about the biology of Australian native Symphyla. They occur in a wide range of macrohabitats and are believed to feed on soil microbes, both 'free' and attached to decaying wood and vegetation. Silk glands open on the two tail-like appendages (cerci) at the rear end of the animal, but uses of the silk have not been well documented.

Tasmanian Symphyla were apparently first noted more than 170 years ago by Henry Hellyer, a surveyor and naturalist employed by the Van Diemen's Land Company. Hellyer was supervising the cutting of a track (later to become Old Surrey Road) in the Emu River valley near Burnie. The track passed through old-growth eucalypt forest with numerous rotting logs and a thick litter layer. On 13 July 1827 Hellyer noted seeing 'young centipedes white as snow', which were almost certainly Symphyla and which are still abundant in the Emu Valley forest.

Nearly 100 years later, Chamberlin (1920) described Tasmaniella hardyi from a single specimen collected in 'Tasmania' by G.H. Hardy. This species was transferred to the genus Hanseniella by Clark & Greenslade (1996) but the type specimen of T. hardyi is in poor condition and its identity and range are uncertain. Hilton (1943) described Scutigerella tasma from Mt Field National Park, but Scheller (1996) says the type specimens no longer exist and Hilton's species diagnosis is inadequate. Neither Tasmaniella hardyi nor Scutigerella tasma was included in Scheller's 1961 review of Australian Symphyla.

Modern work on Tasmanian Symphyla began in the early 1990s with collections made as part of cave studies (Eberhard et al. 1991) and rainforest surveys (Coy et al. 1993, Rushton 1990). Eight new species were described from the rainforest samples (Clark & Greenslade 1996). A ninth, recently described species from the Hastings Caves area, Hanseniella magna, is said to be the largest Symphyla ever collected (Scheller 1996). Large cave forms have also been found in the Junee-Florentine karst (image below).

Identification of Tasmanian Symphyla requires microscopic examination of the dorsal plates (tergites), which are more or less hairy and may also bear long, thin, socketed spines called 'macrochaetae' (see illustrations below).

Close-up of tergite showing a macrochaeta (M) and one of the small setae (circled) that make the tergite look 'hairy'.

[Symphyla illustration based on drawing © Graham Milledge, used with permission, from Harvey, M.S. & Yen, A.L. 1989. Worms to wasps. An illustrated guide to Australia's terrestrial invertebrates. Melbourne: Oxford University Press; 203 pp. Tergite illustration after Scheller (1996).]