Australotomurus Stach 1947

Genus Australotomurus Stach, 1947

Australotomurus Stach 1947: 21.

Type species: Isotomurus echidnus Womersley, 1934, by original designation.

Diagnosis. Scales absent, postantennal organ present, ocelli 8 + 8 on pigmented eye spot, G and H normally reduced in size; only antennal segment I and rarely antennal segment II or III subdivided or III angled, secondary sexual characters present on antennae and occasionally anterior margin of head in male; tenent hair pointed, not clavate; mucro with 2 teeth, mucronal spine absent, manubrium with 2 + 2 ventral distal spines, dens without spines.

Remarks. A fuller diagnosis and figures of characters are given in Mari Mutt and Greenslade (1985). These authors did not describe or figure spines distally on the anterior face of the manubrial thickening although Fjellberg (2007) noted they were present in all European Orchesellinae. These spines have now been observed in both males and females of Australian species.

Australotomurus species are morphologically very similar and furnished with a dense covering of macro- and mesochaetae, which are highly variable in number and pattern within species; therefore, chaetotaxic characters are rarely useful to distinguish species in this genus (Szeptycki 1979; Mari Mutt and Greenslade 1985). The main species diagnostic characters are: male secondary sexual characters; colour pattern and dimensions; form of apical bulb on antennal segment IV and pin seta; ciliation of labial setae; number of teeth on the claw; and number of setae in the trochanteral organ, ventral tube and tenaculum. The terminology of the antennal segments used here slightly differs from that used by Mari Mutt and Greenslade (1985) in that homology with other Collembola taxa is maintained and subsegments are numbered as such (e.g., Antennal segment Ia, Antennal segment Ib) and given separate numbers.