PACHYDIPLAX 245 
230. Pachydiplax longipennis Burmeister 
The Blue Pirate 
Burm. ’39, p. 850: Mtk. Cat. p. 165: Ris ’11, p.619: Kndy. ’17, p. 628: Howe 
’20, p. 78: Ndm. ’23, p. 130: Smn. ’27, p. 36: Garm. ’27, p. 277. 
Length 38 mm. Expanse 64 mm. U. S. generally 
This is a common and widely distributed species of moderate size, striped 
of body when young but becoming wholly pruinose blue with age. Face pale, 
but with top of frons and vertex shining metallic green. Occiput shining brown. 
Thorax nearly bare, brown in front with a pair of divergent narrow yellow stripes 
abbreviated above and a pair of cross streaks below the crest which join 2 very 
irregular narrow yellow antehumeral stripes; sides yellow with 3 brownish stripes 
(stripes 3, 4, 5) diminishing in breadth from front to rear, and confluent above 
at wing roots. Legs black, paler basally. Wings hyaline or tinged with smoky 
brown before the stigma, often broadly flavescent at base with brown streaks 
sometimes present in subcostal and cubital spaces of the hind wing; stigma 
brown. Swollen basal abdominal segments mostly pale at sides; dorsum of 
segments 2-8 with a pair of parallel pale streaks abbreviated at ends. 8-10 and 
appendages blackish. 
Old pruinose blue specimens look quite like old Mesothemis simplicicollis 
but are at once distinguishable by the long space without cross veins behind 
the stigma, in this species. 
Adults of this species are swift of wing and somewhat difficult to 
capture with a net. The males hover near the surface of the water, 
darting hither and thither, meeting every newcomer, perching on a 
twig and immediately quitting it; and, when 2 males meet in combat, 
they have the curious habit of facing each other threateningly, then 
darting upward together into the air and flying skyward, often until 
lost from view. 
The females are less in evidence. They rest habitually, except when 
foraging or ovipositing on trees back from the shore. When ovipositing 
over open water, they have a curious habit which I have not observed 
in other dragonflies: they do not rise and descend again between 
strokes of the abdomen against the surface of the water, but fly hori- 
zontally close to the surface and from time to time strike downward 
with the abdomen alone, presumably washing off eggs. In the midst 
of vegetation, however, they fly down and up again, as do other species. 
The nymphs clamber about among the trash, and when grown, trans- 
form within a few inches of the margin of the water, if suitable place 
be found so near; otherwise they may go a distance of several feet. 
They are smooth, generally of dark color, with little pattern of color 
showing, except in the transverse banding of the femora. 
Williamson says (’00), “‘This species will frequently rest on some 
twig or stem with the wings drooping and the abdomen pointing 
