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Zygentoma (Thysanura) Genera

Definitions

H+B = head and body length excluding antennae and terminal filaments, measured from front of head along body midline until posterior edge of urotergite X.

NSW = New South Wales; NT = Northern Territory; Qld = Queensland; SA = South Australia; Tas = Tasmania; Vic = Victoria; WA = Western Australia; sf = subfamily

[genus/subfamily] brackets in key indicate that this genus has not been recorded in Australia but is present in either Papua New Guinea, New Caledonia or Indonesia

Key to genera

  1.  
    • Eyes present; body with scales, generally pigmented (Fig. 22) Lepismatidae 3
    • Eyes absent; body with or without scales, white or golden (Figs. 34, 65) 2
  2. (1)
    • Body short, oval or tear-drop shaped; scales always present on body (Figs 53, 54); appendix dorsalis and cerci short, generally much less than half H+B; appendix dorsalis sometimes longer than cerci; usually inquiline species (Fig. 65) Ateluridae 17
    • Body subcylindrical, elongate, parallel-sided; scales absent; appendix dorsalis and cerci subequal, usually greater than half H+B; not inquiline species (Fig. 34) Nicoletiidae 12
  3. (1)
    • All bristles bare, at most bifid or trifid apically (Fig. 9); urotergite X rounded (semicircular) (Fig. 13) 4
    • Some macrochaetae feathered or barbed; urotergite X subtriangular or even pointed (Figs. 19, 23) or truncate and sub-rhomboid (Fig. 31) 8
  4. (3)
    • With setal collar (e.g. Fig. 28); Heterolepismatinae: Heterolepisma Escherich
    • Lacking setal collar Lepismatinae 5
  5. (4)
    • Lacking dorsal macrochaetae on both the thoracic and abdominal tergites (although some along thoracic margins); very small species (ca 2-3 mm); pronotum longer than meso- and metanota together; almost one third total body length, head partially concealed (Fig. 15) Undescribed genus A
    • Isolated single or small combs of macrochaetae on tergites; medium to large (> 6 mm), head exposed, pronotum not larger than meso plus and metanota together 6
  6. (5)
    • Thoracic sterna present as shield-like sclerites overlapping the inner margins of the coxa; dorsal macrochaetae single not grouped into small combs (except infralateral combs which consist of 2 macrochaetae and 1 seta); peridomestic species Lepisma Linnaeus
    • Thoracic sterna reduced to small triangular protrusions with tuft of macrochaetae between fully exposed coxae (Fig. 14); some dorsal abdominal macrochaetae grouped into small combs each of just 2–4 setae 7
  7. (6)
    • Presternum large, with scales, extending across segment and almost 1/3 as long as wide (Fig. 17); medial urosternal combs only on urosternite I Undescribed genus B
    • Presternum narrow, without scales and several times wider than long (Fig. 14); most urosternites with small medial comb Anisolepisma Paclt
  8. (3)
    • Setal collar lacking; prosternum shorter than subcoxa, with central tuft of setae (Fig. 14); labial palp papillae in 2+3 arrangement (Fig. 11) Acrotelsatinae: Acrotelsa Escherich
    • Setal collar present (Fig. 28); prosternum generally well developed, without central tuft; labial palp papillae in single row (Fig. 26) Ctenolepismatinae 9
  9. (8)
    • Abdominal terga (at least II–VII) with 2+2 bristlecombs or isolated setae 10
    • Abdominal terga (at least II–VI) with 3+3 bristlecombs 11
  10. (9)
    • Maxillary palp 6of 6 articles (Fig. 20); urosternites III–VI with a medial bristlecomb plus 1+1 lateral combs; peridomestic species Thermobia Bergroth (=Lepismodes Newman)
    • Maxillary palp of 5 articles; urosternites III–VIII with 1+1 macrochaetae, without a medial comb Undescribed genus C
  11. (9)
    • Urotergite X pointed or triangular (possibly slightly rounded apically) (Fig. 23); urotergites II-VII with 3+3 bristlecombs Acrotelsella Silvestri
    • Urotergite X truncate or sub-rhomboid (Fig. 31); urotergites II-VI with 3+3 bristlecombs Ctenolepisma Escherich
  12. (2)
    • Body covered in scales [sf. Coletininae]
    • Body lacking scales Subtrinemurinae 13
  13. (12)
    • Pretarsi with 2 claws [Trinemurodes Silvestri]
    • Pretarsi with 3 claws 14
  14. (13)
    • Urostylets on abdominal segments II–IX [Hemitrinemura Mendes]
    • Urostylets on abdominal segments III–IX 15
  15. (14)
    • Eversible vesicles absent from urosternites III–VI Trinemura Silvestri
    • Eversible vesicles present on urosternites II or III–VI 16
  16. (15)
    • Eversible vesicles present on urosternites II–VI Metrinura Mendes
    • Eversible vesicles present on urosternites II or III–VI Subtrinemura Smith
  17. (2)
    • Stylets on urosternites II–IX, those on III positioned medially (Fig. 62) Australiatelura Mendes
    • Stylets less numerous and never positioned medially 18
  18. (17)
    • Stylets on urosternites VI–IX 19
    • Stylets more numerous (V or IV–IX) Undescribed genus
  19. (18)
    • Vesicles on urosternite VI obvious with row or tuft of setae (Fig. 64) 20
    • Vesicles on urosternite VI absent or inconspicuous 21
  20. (19)
    • Nota with single posterior row of short, flattened deeply cleft macrochaetae (Fig. 61) Pseudogastrotheus Mendes
    • Nota with thin macrochaetae, not flattened and if bifurcated only at tip Ausallatelura Smith
  21. (19)
    • Head hypognathous; almost no macrochaetae with bifurcated tips; males with greatly modified cerci and deflexed urotergite X (Fig. 57) Galenatelura Smith
    • Head prognathous; many macrochaetae with bifurcated tips; cerci of males not strongly modified Allatelura Silvestri

About this key

This key and the following paragraphs are from Zygentoma: a poorly studied order in Australia, by G. B. Smith (2009).

It is too early to offer a reliable key to the Zygentoma in Australia as they are so poorly known. The genera listed as undescribed need more work before their status as new and their subfamily affiliation can be confirmed. This key does not attempt to identify to species as it is more likely than not that specimens collected could be undescribed and would key falsely.

This key will not work outside Australia. The families Lepidotrichidae, Maindroniidae and Protrinemuridae are not known to occur in Australia. Nor do the Nicoletiinae subfamilies Cubacubaninae, Nicoletiinae (s. str. Mendes) or Coletininae although a specimen probably belonging to the Coletininae has been collected in New Guinea. The Lepismatid subfamilies Mirolepismatinae and Silvestrellatinae are also absent, while Acrotelsatinae is only known from the introduced peridomestic Acrotelsa collaris.

This key composed with reference to those of other authors including Smith & Watson (1991), Wygodzinsky (1955, 1957), Mendes (1982, 2004), Paclt (1967), Smith (1998), Watson & Li (1967), Womersley (1937, 1939).

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