DragonflyPix

Unicorn Hunter (Austrogomphus cornutus)

The Unicorn Hunter (Austrogomphus cornutus) is a dragonfly species of the family Gomphidae, which contains 35 species in Australia.

The identification key to the family Gomphidae consists of 47 couplets, 10 of which are pertinent to Austrogomphus cornutus. Click on the numbers on the right to display the corresponding couplets. Or click on the ALLin1 button to see all the relevant couplets together in a single, scrollable window.

#FamilySpeciesCouplet No.
 GomphidaeUnicorn Hunter
(Austrogomphus cornutus)
  • Gomphidae: Key couplet 1 of 47

  • couplet drawingcouplet drawing
  • ● Generally no incomplete antenodal crossvein proximal to Ax1 in any wing
    ● End of abdomen not elongate, mid-dorsal length of abdominal tergum 9 less than 2.3 mm in male, 2.1 mm in female
  • b ↑
  • Gomphidae: Key couplet 10 of 47

  • couplet drawingcouplet drawing
  • ● Superior anal appendages parallel or divergent, not converging at tips, each bearing a long, curved ventrobasal branch
  • a ↑
  • Gomphidae: Key couplet 19 of 47

  • couplet drawing
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  • ● Anterior of abdominal segments 3 and 4 with mid-dorsal yellow band, sometimes narrow, or entirely yellow
  • b ↑
  • Gomphidae: Key couplet 27 of 47

  • ○ Abdominal terga 9-10 usually marked with black or chocolate brown
    ○ If yellow or reddish, then tergum 8 substantially black
  • b ↑
  • Gomphidae: Key couplet 32 of 47

  • couplet drawingcouplet drawing
    couplet drawingcouplet drawing
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  • ● Metanepisternum substantially pale
    ● Pterostigma yellow, brown or black, its length more than 3.3 times its maximum width
  • b ↑
  • Gomphidae: Key couplet 33 of 47

  • couplet drawingcouplet drawing
  • ● Black and yellow or greenish-yellow, lacking lilac colouration
    ● Metepimeron posteriorly not margined with brown
  • b ↑
  • Gomphidae: Key couplet 35 of 47

  • couplet drawingcouplet drawing
  • ● Antehumeral stripe aslant, isolated or its lower end fused with collar
    ● Black mark on lower mesepimeron extending to level of, or engulfing, metastigma
    ● If not, metapleural suture lined with black

    ⇒ genus: Austrogomphus
  • b ↑
  • Gomphidae: Key couplet 39 of 47

  • ○ Abdominal segment 10 black above
  • a ↑
  • Gomphidae: Key couplet 40 of 47

  • couplet drawingcouplet drawing
  • ● Male superior appendage tapering evenly to sharp tip
    ● Rear of female occiput with flattened tooth on each side, behind inner margin of eye, its hind border irregularly serrated
  • b ↑
  • Gomphidae: Key couplet 41 of 47

  • couplet drawing
    couplet drawingcouplet drawing
  • ● Antehumeral stripe broadly fused with collar
    ● Male occiput yellow, with darker edges, greatly swollen, forming blunt triangular horn
    ● Occipital margin of female swollen in centre

    ⇒ species: Unicorn Hunter (Austrogomphus cornutus)
  • b ↑
1  
  • Gomphidae: Key couplet 1 of 47

  • couplet drawingcouplet drawing
  • ● Incomplete (subcostal) antenodal crossvein proximal to Ax1 usually present in forewings, sometimes lacking in hindwings
    ● End of abdomen elongate, mid-dorsal length of abdominal tergum 9 more than 2.4 mm in male, 2.3 mm in female

    ⇒ genus: Antipodogomphus
a ↑
b ↓
  • couplet drawingcouplet drawing
  • ● Generally no incomplete antenodal crossvein proximal to Ax1 in any wing
    ● End of abdomen not elongate, mid-dorsal length of abdominal tergum 9 less than 2.3 mm in male, 2.1 mm in female

2 Male only
  • Gomphidae: Key couplet 10 of 47

  • couplet drawingcouplet drawing
  • ● Superior anal appendages parallel or divergent, not converging at tips, each bearing a long, curved ventrobasal branch
a ↑
b ↓
  • couplet drawingcouplet drawing
    couplet drawingcouplet drawing
    couplet drawingcouplet drawing
  • ● Superior anal appendages converging at tips, bearing basal, ventral to lateral spine or toothed spur

3 Female only
  • Gomphidae: Key couplet 19 of 47

  • couplet drawing
  • ● Anterior part of abdominal segments 3 and 4, in front of supplementary transverse carina, with broad, mid-dorsal black patch or band
a ↑
b ↓
  • couplet drawing
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  • ● Anterior of abdominal segments 3 and 4 with mid-dorsal yellow band, sometimes narrow, or entirely yellow

4  
  • Gomphidae: Key couplet 27 of 47

  • ○ Abdominal terga 9-10 yellow or pale reddish brown
    ○ Tergum 8 similar or with dark reddish brown to black distal half
a ↑
b ↓
  • ○ Abdominal terga 9-10 usually marked with black or chocolate brown
    ○ If yellow or reddish, then tergum 8 substantially black

5  
  • Gomphidae: Key couplet 32 of 47

  • couplet drawingcouplet drawing
  • ● Metanepisternum black, with small yellow dorsal spot
    ● Pterostigma black, swollen, its length less than 3.3 times its maximum width

    ⇒ species: Twinspot Hunter (Austroepigomphus praeruptus)
a ↑
b ↓
  • couplet drawingcouplet drawing
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  • ● Metanepisternum substantially pale
    ● Pterostigma yellow, brown or black, its length more than 3.3 times its maximum width

6  
  • Gomphidae: Key couplet 33 of 47

  • couplet drawingcouplet drawing
  • ● Brown and cream-coloured, with lilac colouration on side of synthorax, or brown and greenish yellow
    ● Lower half of metepimeron posteriorly margined with brown

    ⇒ genus: Zephyrogomphus
a ↑
b ↓
  • couplet drawingcouplet drawing
  • ● Black and yellow or greenish-yellow, lacking lilac colouration
    ● Metepimeron posteriorly not margined with brown

7  
  • Gomphidae: Key couplet 35 of 47

  • couplet drawingcouplet drawing
  • ● Antehumeral stripe with inner margin almost parallel to dorsal carina, its lower end fused with collar
    ● Black mark on lower mesepimeron not extending to metastigma
    ● Metapleural suture not lined with black

    ⇒ genus: Austrogomphus
a ↑
b ↓
  • couplet drawingcouplet drawing
  • ● Antehumeral stripe aslant, isolated or its lower end fused with collar
    ● Black mark on lower mesepimeron extending to level of, or engulfing, metastigma
    ● If not, metapleural suture lined with black

    ⇒ genus: Austrogomphus

8  
  • Gomphidae: Key couplet 39 of 47

  • ○ Abdominal segment 10 black above
a ↑
b ↓
  • ○ Abdominal segment 10 yellow, or black and yellow above

9  
  • Gomphidae: Key couplet 40 of 47

  • couplet drawingcouplet drawing
  • ● Upper surface and sides of male superior appendages narrowing abruptly near apex, producing a very sharp, discrete tip
    ● Rear of female occiput with upturned, variably flattened tooth on each side, behind inner margin of eye, and pair of thick hooks, with out-turned lips, near the midline

    ⇒ species: Murray River Hunter (Austrogomphus angelorum)
a ↑
b ↓
  • couplet drawingcouplet drawing
  • ● Male superior appendage tapering evenly to sharp tip
    ● Rear of female occiput with flattened tooth on each side, behind inner margin of eye, its hind border irregularly serrated

10  
  • Gomphidae: Key couplet 41 of 47

  • couplet drawing
    couplet drawingcouplet drawing
  • ● Antehumeral stripe separated from or just meeting outer corner of collar
    ● Occiput of male black, with yellow spot on slightly swollen margin
    ● Occipital margin of female slightly lower in centre than at sides, not swollen

    ⇒ species: Northern River Hunter (Austrogomphus doddi)
a ↑
b ↓
  • couplet drawing
    couplet drawingcouplet drawing
  • ● Antehumeral stripe broadly fused with collar
    ● Male occiput yellow, with darker edges, greatly swollen, forming blunt triangular horn
    ● Occipital margin of female swollen in centre

    ⇒ species: Unicorn Hunter (Austrogomphus cornutus)

Australian distribution