Shadow Darner

Shadow Darner
Female
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Odonata
Suborder: Anisoptera
Family: Aeshnidae
Genus: Aeshna
Species: A. umbrosa
Binomial name
Aeshna umbrosa
(Walker, 1908)

The Shadow Darner (Aeshna umbrosa) is a species dragonfly in the family Aeshnidae.

Contents

Identification

Adult

The shadow darner is a large dragonfly with a length of 2 5/8 to 3 1/8 inches (68 to 78 mm). The base is brownish black in color. Greenish crescent-shaped spots are at the top of the thorax. The sides of the thorax are marked with two yellowish to yellowish green diagonal stripes. Its abdomen is marked with bluish green spots. The male shadow darner has paddle-shaped anal appendages.

Naiad

The naiad of the shadow darner is large in size, with a length of 1 1/2 to 1 3/4 inches (38 to 43 mm). This naiad is long and slender, which is the typical shape of immature Darners. Its mottled green and brown.

Distribution

Habitat

The shadow darner patrols along small marshy streams. Its often found feeding along woodland edges or even in deep shadow in full forest. Shadow darners can also be found near ditches, slow streams, and ponds.

Flight Season

This darner has a long flight season of late April to November.

Diet

Naiad

The shadow darner naiad feeds on a wide variety of aquatic insects, such as mosquito larvae, other aquatic fly larvae, mayfly larvae, and freshwater shrimp. They also feed on small fish and tadpoles.

Adult

This dragonfly will eat almost any soft-bodied flying insect including mosquitoes, flies, butterflies, moths, mayflies, and stoneflies.

Ecology

The naiad is an active predator and are able to swim by jet propulsion. They squirt water out from the ends of their abdomens. They will generally take several years to mature, and when the immature changes into a dragonfly, they do so at night. This behavior probably was evolved to avoid being eaten be daytime predators. The adult generally flies from late April to November, and do all of their hunting while on the wing. The shadow darner is able to regulate its body temperature which enables it to fly in temperatures too cold for most dragonflies. This dragonfly species in particular seems to be extremely cold tolerant. This dragonfly flies at dusk and in shaded areas, and it flies later into the fall than any species other than the yellow-legged meadowhawk (Sympetrum vicinum).

Reproduction

Male shadow darners establish and defend territories along the shores of slow streams and ponds. After both genders mate, females fly singly, without the male attached, to lay their eggs in the stems and leaves of aquatic plants.

Similar Species

The shadow darner has a vertically flattened cerci with a spike at the end, which is much brighter than the Lance-tipped Darner.

Subspecies

References