DragonflyPix

Red Baron (Urothemis aliena)

The Red Baron (Urothemis aliena) is a dragonfly species of the family Libellulidae, which contains 56 species in Australia.

The identification key to the family Libellulidae consists of 67 couplets, 20 of which are pertinent to Urothemis aliena. 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.
 LibellulidaeRed Baron
(Urothemis aliena)
  • Libellulidae: Key couplet 1 of 67

  • couplet drawing
  • ● Distal antenodal of forewing complete, both costal and subcostal sections present
  • a ↑
  • Libellulidae: Key couplet 1 of 67

  • couplet drawing
  • ● Distal antenodal of forewing incomplete, only the costal section present
  • b ↑
  • Libellulidae: Key couplet 2 of 67

  • couplet drawingcouplet drawing
  • ● Anal loop present
  • b ↑
  • Libellulidae: Key couplet 9 of 67

  • couplet drawing
  • ● Anal loop well developed, generally stocking-shaped, usually closed at tip
  • b ↑
  • Libellulidae: Key couplet 14 of 67

  • ○ Not as above
  • b ↑
  • Libellulidae: Key couplet 15 of 67

  • couplet drawing
  • ● Base of hindwing triangle at or proximal to arculus
    ○ Top of frons, if metallic, dully so
  • b ↑
  • Libellulidae: Key couplet 20 of 67

  • ○ Smaller dragonflies, hindwing up to 40 mm long
    ○ Wings patterned or hyaline
  • b ↑
  • Libellulidae: Key couplet 21 of 67

  • couplet drawing
  • ● Subtriangle of forewing with three or more cells
  • b ↑
  • Libellulidae: Key couplet 24 of 67

  • ○ Forewing triangle free
  • a ↑
  • Libellulidae: Key couplet 25 of 67

  • ○ Fewer than nine antenodal crossveins
  • b ↑
  • Libellulidae: Key couplet 26 of 67

  • couplet drawingcouplet drawing
  • ● Abdomen of male red above except for small, mid-dorsal dark spots on segment 8-9
    ● Vulvar scale of female elongate, extending the length of segment 9

    ⇒ species: Red Baron (Urothemis aliena)
  • a ↑
  • Libellulidae: Key couplet 35 of 67

  • couplet drawing
  • ● Hindwing triangle free
  • b ↑
  • Libellulidae: Key couplet 39 of 67

  • ○ Not as above
  • b ↑
  • Libellulidae: Key couplet 40 of 67

  • couplet drawing
  • ● Base of hindwing triangle at or slightly proximal to arculus
  • b ↑
  • Libellulidae: Key couplet 41 of 67

  • couplet drawing
  • ● Tip of anal loop closed, the bounding veins meeting midvein one row of cells away from wing margin
  • b ↑
  • Libellulidae: Key couplet 45 of 67

  • couplet drawingcouplet drawing
  • ● Subtriangle of forewing with one to three cells, its basal side well-defined
  • a ↑
  • Libellulidae: Key couplet 46 of 67

  • ○ Smaller dragonflies, hindwing shorter than 38 mm
  • b ↑
  • Libellulidae: Key couplet 47 of 67

  • couplet drawing
  • ● Discoidal field of forewing, between triangle and level of origin of IR3, starting with two or three rows of cells, followed by two rows
  • b ↑
  • Libellulidae: Key couplet 49 of 67

  • ○ Hindwing 30 mm or longer
  • a ↑
  • Libellulidae: Key couplet 50 of 67

  • ○ Fewer than nine antenodal crossveins

    ⇒ species: Red Baron (Urothemis aliena) (part)
  • a ↑
1 (part)
  • Libellulidae: Key couplet 1 of 67

  • couplet drawing
  • ● Distal antenodal of forewing complete, both costal and subcostal sections present
a ↑
b ↓
  • couplet drawing
  • ● Distal antenodal of forewing incomplete, only the costal section present

2 (part)
  • Libellulidae: Key couplet 1 of 67

  • couplet drawing
  • ● Distal antenodal of forewing complete, both costal and subcostal sections present
a ↑
b ↓
  • couplet drawing
  • ● Distal antenodal of forewing incomplete, only the costal section present

3  
  • Libellulidae: Key couplet 2 of 67

  • couplet drawing
  • ● Hindwing lacking anal loop

    ⇒ genus: Nannophya
a ↑
b ↓
  • couplet drawingcouplet drawing
  • ● Anal loop present

4  
  • Libellulidae: Key couplet 9 of 67

  • couplet drawing
  • ● Anal loop rounded, poorly developed, of three to five cells
a ↑
b ↓
  • couplet drawing
  • ● Anal loop well developed, generally stocking-shaped, usually closed at tip

5  
  • Libellulidae: Key couplet 14 of 67

  • couplet drawingcouplet drawing
  • ○ Small (hindwing c. 25 mm)
    ● Synthorax and abdomen black with well-defined pale yellowish green markings

    ⇒ species: Forestwatcher (Huonia melvillensis) (part)
a ↑
b ↓
  • ○ Not as above

6  
  • Libellulidae: Key couplet 15 of 67

  • couplet drawing
  • ● Base of hindwing triangle just beyond to well beyond arculus
    ○ Top of frons brilliant metallic blue or green, particularly in male
a ↑
b ↓
  • couplet drawing
  • ● Base of hindwing triangle at or proximal to arculus
    ○ Top of frons, if metallic, dully so

7  
  • Libellulidae: Key couplet 20 of 67

  • ○ Large dragonflies, hindwing 45 mm or longer, wing membrane extensively marked with reddish- or blackish-brown

    ⇒ species: Black Knight (Camacinia othello) (part)
a ↑
b ↓
  • ○ Smaller dragonflies, hindwing up to 40 mm long
    ○ Wings patterned or hyaline

8  
  • Libellulidae: Key couplet 21 of 67

  • couplet drawing
  • ● Subtriangle of forewing single-celled
a ↑
b ↓
  • couplet drawing
  • ● Subtriangle of forewing with three or more cells

9  
  • Libellulidae: Key couplet 24 of 67

  • ○ Forewing triangle free
a ↑
b ↓
  • couplet drawing
  • ● Forewing triangle crossed

10  
  • Libellulidae: Key couplet 25 of 67

  • ○ More than nine antenodal crossveins

    ⇒ species: Red Arrow (Rhodothemis lieftincki) (part)
a ↑
b ↓
  • ○ Fewer than nine antenodal crossveins

11  
  • Libellulidae: Key couplet 26 of 67

  • couplet drawingcouplet drawing
  • ● Abdomen of male red above except for small, mid-dorsal dark spots on segment 8-9
    ● Vulvar scale of female elongate, extending the length of segment 9

    ⇒ species: Red Baron (Urothemis aliena)
a ↑
b ↓
  • couplet drawingcouplet drawing
  • ● Abdomen of male red with mid-dorsal black stripe
    ● Vulvar scale of female vestigial

    ⇒ species: Wandering Pennant (Macrodiplax cora)

12  
  • Libellulidae: Key couplet 35 of 67

  • couplet drawing
  • ● Hindwing triangle crossed
a ↑
b ↓
  • couplet drawing
  • ● Hindwing triangle free

13  
  • Libellulidae: Key couplet 39 of 67

  • couplet drawingcouplet drawing
  • ○ Small (hindwing c. 25 mm)
    ● Synthorax and abdomen black with well-defined pale yellowish-green markings

    ⇒ species: Forestwatcher (Huonia melvillensis) (part)
a ↑
b ↓
  • ○ Not as above

14  
  • Libellulidae: Key couplet 40 of 67

  • couplet drawing
  • ● Base of hindwing triangle well beyond arculus

    ⇒ species: Spiny-Chested Percher (Raphismia bispina)
a ↑
b ↓
  • couplet drawing
  • ● Base of hindwing triangle at or slightly proximal to arculus

15  
  • Libellulidae: Key couplet 41 of 67

  • couplet drawing
  • ● Tip of anal loop usually open on one or both sides of midvein, the bounding veins of loop extending to wing margin, occasionally closed, the bounding veins meeting at wing margin
a ↑
b ↓
  • couplet drawing
  • ● Tip of anal loop closed, the bounding veins meeting midvein one row of cells away from wing margin

16  
  • Libellulidae: Key couplet 45 of 67

  • couplet drawingcouplet drawing
  • ● Subtriangle of forewing with one to three cells, its basal side well-defined
a ↑
b ↓
  • couplet drawingcouplet drawing
  • ● Basal side of forewing subtriangle poorly defined
    ● If recognisable, containing more than three cells

17  
  • Libellulidae: Key couplet 46 of 67

  • ○ Large dragonflies, hindwing longer than 38 mm
    ○ Male abdomen black, with dorsal pairs of yellow spots

    ⇒ species: Water Prince (Hydrobasileus brevistylus) (part)
a ↑
b ↓
  • ○ Smaller dragonflies, hindwing shorter than 38 mm

18  
  • Libellulidae: Key couplet 47 of 67

  • couplet drawing
  • ● Discoidal field of forewing containing three rows of cells, occasionally four, between triangle and level of origin of IR3
a ↑
b ↓
  • couplet drawing
  • ● Discoidal field of forewing, between triangle and level of origin of IR3, starting with two or three rows of cells, followed by two rows

19  
  • Libellulidae: Key couplet 49 of 67

  • ○ Hindwing 30 mm or longer
a ↑
b ↓
  • ○ Hindwing shorter than 30 mm

20  
  • Libellulidae: Key couplet 50 of 67

  • ○ Fewer than nine antenodal crossveins

    ⇒ species: Red Baron (Urothemis aliena) (part)
a ↑
b ↓
  • ○ More than nine antenodal crossveins

    ⇒ species: Red Arrow (Rhodothemis lieftincki) (part)

Australian distribution