Macromia pinratani vietnamica Asahina, 1996

 

Macromia pinratani Asahina (1983) has been described from Thailand. Macromia pinratani vietnamica is a northern Vietnam subspecies.

A resting male

Macromia pinratani is a large-sized dragonfly, with a reddish-brown synthorax marked on sides with 2 wide, shiny green metallic stripes enclosing a pale yellowish area. The abdomen is black, ringed and spotted with pale yellow and brown (with an obvious yellow ring on S7 in both sexes).

Wings hyaline, more or less enfumed with yellow-brown in aged specimens.

 

Male

Male

  Dorsal view

Caudal appendages black and are of typical Macromia type: superiors with a small spine on the middle of the outer side; inferior appendage triangular, narrow.
Segment 10 unmarked, strongly keeled above with an upstanding dorsal process.

Lateral view

Female (photo above) closely resembles the male save for sexual characters ; differs by its more robust build, the more extensive and conspicuous yellow markings on abdomen.

Wings, male : anal loop of hind wing well defined, rounded, 
characteristic feature of Macromids (anal loop elongate in Cordulids).

Macromia pinratani vietnamica differs from the nominotypical subspecies as follows (from Asahina, in « Records of the Northern Vietnamese Odonata taken by the expedition members from the National Science Museum, Tokyo, 1996. Part III : Aeschnidae, Corduliidae, Libellulidae”) :

-larger in size (hindwings lenght)

-metallic greenish ground colour of the body deeper. The yellowish or brownish stripes of the abdominal segments are much more developed than those of the nominotypical race described from Thailand. In particular, the yellow bands of the 2-7 abdominal segments are strongly developed in both sexes

-the upstanding dorsal process of the last abdominal segment in the male is very strong

-the genitalia hamulus of the male is well developed

M. pinratani is rarely stays far from its watery habitat and is to be found patrolling slowly along streams at a few feet from the water or flying rapidly along roads in forest.
The females are rarely seen, and appear to keep to jungle, except for brief intervals when they come to oviposit and then depart again, pairing taking place during these short visits to water.

M. pinratani is known from Thailand, Laos and northern Vietnam. In my area around Hanoi, it is a common sight along forested well-shaded rocky streams and brooks, in hill and montane regions, including disturbed forest. 　

Macromids are among the most elusive of all dragonflies. Nevertheless, M. pinratani is a conspicuous insect - the male at least - and one of the Anisoptera I encountered the most along sub-montane and montane forest streams. But I bumped only a few times into resting individuals...