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Dragonflies: Suborder Anisoptera

Relatively stout-bodied, about 1-33^ in. HW broader at base than FW, the wings at rest held outstretched, cf with 3 terminal abdominal appendages, 2 above and 1 below. 9 with only 2 (dorsal) terminal appendages. 9 of some groups with an ovipositor, located on ventral side of terminal abdominal segments, giving end of abdomen a somewhat swollen appearance. Nymphs robust, with gills in rectum; breathing is accomplished by drawing water into rectum through anus, and then expelling it; this expulsion of water serves as a means of locomotion, the insect thus moving by "jet" propulsion.

Graybacks, Clubtails, Darners, and Biddies: Superfamily Aeshnoidea

Triangles in FW and HW similar in shape and location. Most antenodal cross veins between C and Sc not in line with those between Sc and R. A brace vein at proximal end of stigma (except Cordulegastridae). Wings nearly always clear, without spots or bands. Ovipositor present or absent.

GRAYBACKS Family Petaluridae

Identification: Large grayish-brown or blackish dragonflies, about 3 in. Compound eyes do not meet on dorsal side of head. Median lobe of labium notched. Stigma at least 8 mm. Ovipositor well developed.

Two species of graybacks occur in the U.S., 1 in the East and 1 in the West; both are rare and local. Eastern species, Tach-opteryx thoreyi (Hagen), is grayish brown and found along small streams in wooded valleys. Western species, Tanypteryx hageni (Selys), is blackish, and occurs at high elevations in mountains. Graybacks often alight on tree trunks, where their color blends with that of the bark.

CLUBTAILS Family Gomphidae See also PL 1

Identification: Compound eyes do not meet on dorsal side of head. Medium lobe of labium not notched. Stigma less than 8 mm. Terminal segments of abdomen sometimes dilated. $ lacks ovipositor.

Members of this large group occur along streams or shores of large lakes. Most species are 2-3 in., and dark brown with yellowish or greenish markings. Flight is usually steady, without periods of hovering; some occasionally fly with a very undulating flight. Adults often alight on a flat surface.

DARNERS Family Aeshnidae See also PL 1

Identification: Compound eyes in contact for a considerable distance on dorsal side of head. Ovipositor well developed.

This group includes our largest dragonflies. Most species are 2J4-334 in., and a few may reach 3 J^ in. or more. All are strong fliers, difficult to catch. Most species are dark brown, often with bluish or greenish markings. The Green Darner (Pl. 1), A nax junius (Drury), a common species found around ponds, has a light green thorax, bluish abdomen and a targetlike mark on upperpart of the face. Aeshna is a large and widely distributed genus whose members are mostly dark-colored, with bluish markings. Darners generally occur around ponds and swamps.

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