Suborder Zygoptera
Family Coenagrionidae

The largest family of Zygoptera, with nineteen known genera in the Papuan region. Inhabit a wide range of habitats, although most common over still or sluggish waters and in hot, sunny, exposed conditions. Males of many species are brightly coloured and participate in conspicuous territorial and mate-seeking behaviors. Many species breed in new or temporary ponds and puddles. Coenagrionid habitats are characteristically densely populated.


Key to the subfamilies and genera of Papuan Coenagrionidae (including the Argiinae)

1 Tibial spines long, generally about twice as long as intervening spaces, often much longer (as shown below). Petiolation of wings ceases before level of Ac. Usually four cells between quadrilateral and level of subnodus in forewing. Usually 14-20 postnodals in forewing. Hindwing quadrilateral variable but generally widened distally (below, left)subfamily Argiinae 2


-Tibial spines shorter, scarcely longer than intervening spaces; if long, wings are petioled to or beyond Ac. Three cells between quadrilateral and subnodus in forewing. Usually only 6-14 (as many as 17) postnodals in forewing. Hindwing quadrilateral generally not widened distally (below, right)subfamily Coenagrioninae 5

 

Long tibial spines (Papuargia)
Long tibial spines (Papuargia)
Hindwing quadrilateral figure
Hindwing quadrilateral. Argiinae (Archboldargia)
left, Coenagrioninae (Austroallagma) right.

2 Male abdomen + appendices 41.5-42.5 mm, hindwing 30.5-31.0; female 35.8-38.0, 29.0-31.5. Wings greatly attenuated, greatest width to length of forewing from 1:6 to 1:6.4. Prothoracic lobe of both sexes and terminalia of male remarkably bizarre structures of enormous size and intricate build (in dorsal view paraprocts resembling pair of antlers, with at least three distinct inwardly directed lobes). Males vivid green, bright blue, and red contrasting with black Archboldargia Lieftinck (3 sp.)

- Moderately sized (male abdomen + appendices typically from 30.0-35.0 mm). Wings not so greatly attentuated. Prothoracic lobe of both sexes and terminalia of male not so large or unusual

3 Four cells between quadrilateral and level of subnodus in hindwing. Labium with median lobe deeply cleft, free lobes about 1/3 of length of labium itself. Prothorax with median division provided with robust conical tubercle on either side of the middle. Legs comparatively short and robust, bristles strong, spine-like, less numerous and much shorter than in next two genera, those on basal portion of posterior tibiae scarcely three times longer than intervening spaces (as shown above). Male cerci with apical tooth-like projection. Female genital valves not toothed along lower margin (below, left) Papuargia Lieftinck (1 sp.)

- Only three cells between quadrilateral and level of subnodus in hindwing. Median cleft of mid-lobe of labium short, free lobes much less than 1/3 of length of labium itself. Prothorax with median division unarmed. Legs comparatively long and slender; bristles of femora and tibiae long and fine, those on basal portion of posterior tibiae at least five times longer than intervening spaces (as shown below). Male cerci unarmed. Female genital valves with number of small teeth along lower margin (below, right) 4

Tibial spines (Palaiargia )
Tibial spines (Palaiargia )

Female genital valves
Female genital valves.
Papuargia stüberi (left). Palaiargia perimecosoma (right).

4 Wings shorter in relation to width, about 4.5 times as long as wide. Bristles on basal portion of posterior tibiae at least six times longer than intervening spaces. Male cerci about as long as S10, variable in shape, paraprocts also variable but always exposed in lateral view and usually at least half the length and often equal in length to cerci Palaiargia Förster (25 sp.)

- Wings much longer in relation to width, about 5.5 times as long as wide. Bristles on basal portion of posterior tibiae about 5-6 times longer than intervening spaces. Male cerci 1.0-1.5 times the length of S10, mitten-shaped in lateral view, paraprocts fingerlike, mostly hidden from side-view, about half as long as cerci Hylaeargia Lieftinck (2 sp.)

5 No pale postocular spots present; rear of head unicolorous (below, left) 6

- Pale postocular spots present on a dark background (spots may be obscured in badly preserved specimens, or covered by pruinosity), these spots sometimes confluent with the light coloring of the rear of the head (below, right), apparently so in those genera with dichromatic females 12

No postocular spots (Ischnura aurora viduata)
No postocular spots (Ischnura aurora viduata), left;
Postocular spots present (Oreagrion oreadum, ♀ and ♂), right.

6 Frons smoothly rounded, without any trace of a transverse ridge. Female with apical spine on venter of S8 (below, left) 7

- Frons bearing a prominent, transverse frontal ridge that divides the frons into a horizontal dorsal portion and a vertical anterior portion. Female without apical spine on venter of S8 (below, right) 9

Apical spine on venter of S8
Apical spine on venter of S8 (Austroallagma sagittiferum), left;
No spine on venter of S8 (Oreagrion oreadum), right.

7 Pt of male forewing differs from that of hindwing in color, size, or both. Subapical tooth of tarsal claw distinctly smaller than apical tooth. Coloration black with pale areas green, orange, or obscured with pruinosityIschnura Charpentier (Part)

- Pt of male forewing and hindwing similar in color and size. Subapical tooth of tarsal claw almost as large as apical tooth. Coloration largely black and blue 8

8 Legs extremely long, hind femora reaching to or beyond distal border of S2. Postnodal cells of the second row, at least in Hindwing, all of about the same size (last cell before the brace vein may be somewhat larger, but not twice as large as its neighbors) Austrocnemis Tillyard (1 sp.)


- Legs not unusually long, hind femora not reaching beyond distal border of S1. Brace vein under proximal end of stigma preceded by a space distinctly longer than—often twice as long as—the cells before and after it in the second row (as shown below) Xiphiagrion Selys (2 sp.)

 

Extended cell before stigmal brace-vein (Xiphiagrion cyanomelas)
Extended cell before stigmal brace-vein (Xiphiagrion cyanomelas).

9 Head and thorax unicolourous, without any dark markings. Colours non-metallic, usually yellow, green, orange or red. Ac situated nearer Ax1 than Ax2. Origin of Ab at Ac or slightly but distinctly proximal to it. R4+5 arising distinctly before subnodus and curved at base, IR3 at the subnodus, both veins not closely approximated at origin. Tarsal claws with distinct inferior tooth. No conspicuous median plate or process situated between cerci, below posterior margin of S10. Cerci simple Ceriagrion Selys (2 sp.)

- Head and thorax at least partly black, or with metallic sheen. Ac situated at level about half-way between Ax1 and Ax2, or nearer Ax2 than Ax1. Origin of Ab usually distinctly distal to Ac, rarely at point where Ac meets wing-margin. Position of R4+5 and IR3, and tarsal claws, variable. Chitinous plate- or tongue-shaped median process, highly variable in size and shape, originating from body-wall below posterior margin of S10, and situated between cerci. Cerci, from base out, composed of two distinct branches (lower branch sometimes obsolete) (as shown below) 10

 

Ventro-posterior view of male terminalia
Ventro-posterior view of male terminalia,
showing upper & lower branches of cerci (Teinobasis wallacei).

10 R4+5 strongly curved basally and arising very distinctly before subnodus, while IR3 coincides with subnodus, both veins hence not fused nor approximated at origin. Ab arises from posterior border of wing at point where Ac meets it, rarely slightly distad to Ac. Course of MA and A1 broken for long distance, i.e. MA being zig-zagged at, before, or slightly after middle of its length, A1 broken up at or slightly beyond level of subnodus. Tarsal claws with inferior tooth (obsolete in occipitale). Rather robust Papuagrion Ris (23 sp.)

- R4+5 straight or but slightly curved basally and arising at or very near (even slightly basal) to subnodus, IR3 at or trace beyond it, both veins hence very closely approximated at origin, or even fused for one cell length. Ab fusing with posterior border of wing distad to Ac, for distance at least as long as length of Ac itself. Course of MA and A1 normal, i.e. only extreme apical (marginal) portion of MA zig-zagged and A1 straight for long distance (3-4 cells) beyond level of subnodus. Tarsal claws usually without inferior tooth. Slender 11

11 Hind femora reaching beyond posterior margin of pterothorax. Distal spines of hind femora almost twice as long as the space between them. Apical margin of male S10 deeply excavated (ca. 1/3 dorsal length of S10), the two lateral edges of this concavity fringed with long hairs (as shown below). Antennae very long: when stretched out transversely projecting beyond margin of eye for more than 1.5 mm. Plagulibasis Lieftinck (1 sp.)

- Hind femora not reaching to posterior margin of pterothorax. Distal spines of hind femora not more than 1.5 times as long as the space between them. Apical margin of male S10 not so deeply excavated, nor fringed with long hairs. Antennae shorter: when stretched out transversely projecting not more than 1.0 mm beyond eye margin. Teinobasis Kirby (36 sp.)

 

Terminalia of Plagulibasis (from Ris, 1913)
Terminalia of Plagulibasis (from Ris, 1913).

12 Medio-anal link straight or nearly so (below, left). Hindwings in both sexes noticeably shorter than forewings (male forewing 19.0 mm, hindwing 17.5). Male creamy-white with distinct black markings, female dark reddish-brown without definite markings. Distribution: New Britain, Umboi I., Admiralty Islands Mortonagrion Fraser (1 sp.)

- Medio-anal link zig-zagged to wing margin (below, right). Both sexes with fore- and hindwings more or less equal in length 13

Medio-anal link straight
Medio-anal link straight (Mortonagrion), left.
Medio-anal link zig-zagged (Agriocnemis), right.

13 Arculus situated distinctly beyond level of Ax2. Both wings not petioled to Ac, but vein from Ac back to wing margin, that is A', does not continue in direction of petioled part of margin; instead it passes up toward Ac and Ab 14

- Arculus not distinctly beyond Ax2, or if so, either one wing petioled to Ac or vein A' continues direction of hind margin of wing up to point of petiolation 15

14 Arculus in hindwing situated beyond Ax2 by at least the length of the upper portion of the arculus itself. Postnodals five to nine. Mature females dichromatic, either olive green or red. Very small damselflies, entire body length usually < 24.0 mm, hindwing < 14.0 Agriocnemis Selys (4 sp.)

- Arculus in hindwing much nearer to Ax2. Postnodals up to twelve. Mature females not dichromatic, colored blue and black. Chiefly insects of moderate size, i.e. abdomen ≥ 25.0 mm, hindwing ≥ 14.0 Argiocnemis Selys (2 sp.)

15 Female without apical spine on venter of S8 (below, right) 16

- Female with apical spine on venter of S8 (below, left) 19

Apical spine on venter of S8
Apical spine on venter of S8 (Austroallagma sagittiferum), left;
No spine on venter of S8 (Oreagrion oreadum), right.

16 Pt of forewing differing from that of hindwing in size, color or both, at least in the male Ischnura Charpentier (Part)
[species currently placed into Oreagrion Ris]

 

- Pt of male fore- and hindwing similar in size and color 17

17 Pt about as long as wide, only slightly oblique, and very small, somewhat shorter than the cell below it (below, left). Tarsal claw without an inferior tooth. R4+5 arising proximal to but very near the subnodus, almost touching base of IR3 Archibasis Kirby (3 sp.)

- Pt markedly longer than wide, distinctly oblique, and as long or longer than the cell below it (below, right). Tarsal claw generally with an inferior tooth. R4+5 –at least in Forewing—arising more distinctly (about a half cell-length) before the subnodus 18

Pterostigmata
Pterostigmata. Archibasis mimetes (left). Austroagrion cyane (right).

18 Antealar sinus of male partially to substantially pale (as shown below). Posterior lobe of female pronotum (where known) with forwardly-directed, fingerlike process on each side. Both sexes with anal vein (at least in Forewing) leaving wing margin basal to Ac, forming a short stalk Pseudagrion Selys (15 sp.)

- Antealar sinus of male black. Posterior lobe of female pronotum without forwardly- directed, fingerlike process on each side. Both sexes with anal vein leaving wing margin at Ac Austroagrion Tillyard (2 sp.)

 

Dorsal view of pterothorax, showing pale antealar sinus (Pseudagrion)
Dorsal view of pterothorax, showing pale antealar sinus (Pseudagrion).

19 Anal vein leaving wing margin well basal to the level of Ac in both wings, so that there is a basal segment of anal vein about the same length as Ac (as shown below). Veins IR3 and R4+5 distinctly separated at level of subnodus. Pt of male forewing differs distinctly from that of hindwing in color, size, or both. Hind margin of male S10 typically produced into a raised prominence or tubercle
Ischnura Charpentier (15 sp. & ssp.)
[properly including Oreagrion Ris, 4 sp.]

 

- Anal vein leaving wing margin nearer to or beyond level of Ac; basal segment of hindwing anal vein, if present, not more than half length of Ac. Veins IR3 and R4+5 almost touching at the subnodus. Pt of male forewing only slightly larger than that of hindwing, and of similar color. Hind margin of male S10 not produced into a raised tubercle 20

Anal vein basal to Ac (Oreagrion lorenzt).
Anal vein basal to Ac (Oreagrion lorenzt).

20 Tarsal claws with well-developed subapical tooth. Ac situated nearer Ax1 than Ax2. Penis without denticles on inner surface of third segment and lacking latero- marginal spine. Male S8-10 entirely blue. Male S2 marked with black as shown below. Slightly larger species, male abdomen + appendices 23.5-25.5 mm, hindwing 15.5-16.5. Distribution: Sumba, Tanimbar Islands Austroallagma Lieftinck (1 sp.)


- Tarsal claws without, or with only a vestigial subapical tooth. Ac situated mid-way between Ax1 and Ax2. Penis with denticles on inner surface of third segment and with latero-marginal spine. Male S8-9 blue variably marked with black dorsally, S10 black dorsally, blue at the sides. S2 of male not marked as shown for Austroallagma. Slightly smaller species, male abdomen + appendices 22.5-23.5 mm, hindwing 13.5- 14.7. Distribution: New Guinea, N. Australia, Aru Islands, Buru
Aciagrion Selys (2 sp.)

Dorsal abdominal markings, S1-3, Austroallagma sagittiferum.
Dorsal abdominal markings, S1-3, Austroallagma sagittiferum.
(from Watson et al, 1991)

References: Ishida et al (1988); Lieftinck (1935), pp. 236-237; Lieftinck (1937b), pp. 102-104; Lieftinck (1938), pp. 101-102; Lieftinck (1949b), p. 347; Munz (1919), pp. 57-63; Needham (1930), p. 238; Watson et al (1991), pp. 120-122.

 

Representative Coenagrionidae of the Papuan Region
Representative Coenagrionidae of the Papuan Region