Key to the Australian genera and species of Orchesellidae

1 Body scales present, dorsal macrochaetotaxy mostly reduced................................................... 2

- Body scales absent, dorsal macrochaetotaxy complex.................................. Australotomurus Stach, 1947

a. Males’ Ant. II with dimorphic chaetae, Ant. III without dimorphic chaetae, dorsal head with S0’ and S4i mac, M0 absent, Abd. II a3a mac present, Abd. IV without T6 mac.......................................................... b

-. Males’ Ant. II without dimorphic chaetae, Ant. III with five strong mac, dorsal head with M0 and without S0’ and S4i mac, Abd. II a3a mac absent, Abd. IV with T6 mac.............................. A. morbidus Greenslade & Jordana, 2014

b. Males’ antero-lateral head without remarkably thick spines, dorsal head with Ps2 and without A3e mac.............. c

-. Males’ antero-lateral head with 3–5 remarkably thick spines, dorsal head with A3e and without Ps2 mac............................................................................. A. womersleyi Mari-Mutt & Greenslade, 1985

c. Ant. II undivided (antennae with five segments), males’ antero-lateral head without clearly modified chaetae, dorsal head and Abd. III without S4a and a2a2 mac, respectively....................................................... d

-. Ant. II basally subsegmented (antennae with six segments), males’ antero-lateral head with a dense cluster of about 65 short ciliated chaetae, dorsal head and Abd. III with S4a and a2a2 mac, respectively … A. barbatus Mari-Mutt & Greenslade, 1985

d. Dorsal head with M1–2 and S2, and without Ps5 mac, unguis with 2–3 inner teeth, without the paired proximal teeth …. e

-. Dorsal head with Ps5, and without M1–2 and S2 mac, unguis with four inner teeth, with the paired proximal teeth........................................................................ A. montanus Mari-Mutt & Greenslade, 1985

e. Males’ Ant. II internally with clusters of clearly modified chatae, 1–3 of them very large, dorsal head with A6p, M3i, and S5a and without S5i and Ps3 mac, Abd. II and Abd. IV without m4 and A5 mac, respectively, trochanteral organ with 35 or less spine-like chaetae, tenaculum with 7–9 chaetae.............................................................. f

-. Males’ Ant. II dimorphic chaetae less discernible, dorsal head with S5i and Ps3 and without A6p, M3i, and S5a mac, Abd. II and Abd. IV with m4 and A5 mac, respectively, trochanteral organ with about 45 spine-like chaetae, tenaculum with 15 chaetae........................................................................ A. echidnus (Womersley, 1934)

f. Males’ Ant. II straight, labial basomedian field with 10 ciliate chaetae internal to E, dorsal head with A3, A4–4e, S1e, and S4e mac, Abd. II without p4 mac, Abd. IV without A1, A3, Ae1–2, Be2, xp, and T1 mac, unguis with two unpaired inner teeth........................................................... A. immodestus Mari-Mutt & Greenslade, 1985

-. Males’ Ant. II internally angled, labial basomedian field with 5–8 ciliate chaetae internal to E, dorsal head without A3, A4–4e, S1e, and S4e mac, Abd. II with p4 mac, Abd. IV with A1, A3, Ae1–2, Be2, xp, and T1 mac, unguis with three unpaired inner teeth.......................................................... A. johanni Mari-Mutt & Greenslade, 1985

2 Postantennal organ absent.............................................................................. 3

- Postantennal organ present........................................................... Alloscopus Börner, 1906

-. Eyes 1+1, tibiotarsi with two rows of smooth chaetae, dens with 3–7 spines in a single row … A. tetracanthus Börner, 1906

3 Abd. I dorsally without mac, Abd. V with three sens.......................................................... 4

- Abd. I dorsally with mac, Abd. V with four or seven sens.............................. Dicranocentrus Schött, 1893

-. Four needle-like labral papillae present, dorsal head with S0, S2, Pa2–3e, Pm3, Pp2–3, Pp5 mac, A1 and Ps mac absent, ventral head posterior chaetae ciliate, Th. II–Abd. IV central mac formula as 12,9|3,2,2,3, tibiotarsi and manubrium without rows of smooth chaetae, unguis with a minute apical tooth, dens without a proximal differentiated chaeta, dental spines absent....................................................................................... D. dolosus sp. nov.

4 Unguiculus lanceolate, proximal dens without a sinuous mac............................. Heteromurus Wankel, 1860

-. Eyes 8+8, labral papillae absent, labial basomedian field without scales, tibiotarsi without rows of smooth chaetae, tenenthairs spatulate, unguis with four inner teeth............................................. H. major (Moniez, 1889)

- Unguiculus excavated (basally swollen with the apical internal region concave), proximal dens with a sinuous ciliate mac................................................................................. Falcomurus Mandal, 2018

a. Labrum with four papillae, ventral head post-labial quadrangle without smooth chaetae, ventral tube lateral flap with about nine ciliate and six smooth chaetae...................................... F. hilli Bellini, Souza & Greenslade, 2021

-. Labrum with two papillae, ventral head post-labial quadrangle with two smooth chaetae, ventral tube lateral flap with about 22 smooth chaetae.............................................. F. pulukokos Bellini, Souza & Greenslade, 2021