Damselfly Nymph

Large eyes, wingpads (= partially developed wings) on their backs, three leaf-shaped gills projecting off the back.  Often red-brown, green-brown, or black.  Find damselfly nymphs clinging to vertical vegetation.  Similar to dragonflies but with leaf-shaped gills rather than pointed projections on the back end.  

Immature damselfly.  (0.5cm—4cm)

Predaceous Diving Beetle

Quite active in the water, smooth and rounded for swimming, long swimming hairs on legs, straight antennae.  Huge variation in shape, color, and size 

among species.  Find these beetles swimming through the water, especially when they surface to breathe.  Difficult to distinguish these beetles from the water scavenger beetles without handling, but typically more active.  (0.2cm—3.5cm)

Water Scavenger Beetle

Smooth and rounded for swimming, long swimming hairs on legs, clubbed antennae, most with a long pointed spike on underside.  Wide variation in shape, color, and size, though usually darkly colored.  Find these beetles swimming or crawling on the bottom.  Difficult to distinguish from the predaceous diving beetles without handling, but often less active.  (0.4cm—4cm)

Whirligig Beetles

Rounded bodies, long front legs, other legs very short, eyes divided on each side (4 total eye regions).  Deep black and either small or large depending on variety.  Find these beetles swimming on the surface of the water in groups. Shape, eye division, and leg lengths are 

distinct.  (0.5cm—1.5cm)

Mayfly

Large eyes, gills along abdomen, 3 tails, typically long, narrow bodies and fish-like movements.  Often light colored.  Find these crawling along the bottom or attached to vegetation.  Distinguish a mayfly from a 

damselfly by the tails: 3 long, slender tails on the mayfly are unlike the 3 leaf-like gills on the damselfly.  (0.4cm—1.8cm)

Horse Fly Larva

Large larvae, no legs, indistinct head region, body ringed with leglike structures that give them a ribbed appearance.  Usually light brown, yellow, or white.  Find these flies at the bottom of the pond in muck.  Similar in size to crane fly larvae, but the ribbing is distinct.  (1cm—4cm)

Crane Fly Larva

Large larvae, no legs, indistinct head region, body ends with a ring of pointed fleshy projections.  Usually brown.  Find these flies at the bottom of the pond in muck.  Similar in size to horse fly larvae, but lacks the ribbed appearance and has the fleshy projections.  (1cm—4cm)

Mosquito Larva

Elongate, narrow larvae, broad head, thorax wider than head, breathing tube and bristles on back end, no legs.  Usually light brown or grey.  Find these flies upside down at the surface, sticking the respiratory tube out of the water, or wriggling near the surface if disturbed. Enlarged thorax is distinct.  (0.4cm—1.2cm)

Bloodworm

Small, elongate larvae, no legs, distinct head, very small, two leg -like structures on back end and one below head.  Usually bright red.  Find these flies at the bottom of the pond in muck.  Bright red coloration is distinct, as is the shape of these flies. Larvae of nonbiting midges.  (0.2cm—1cm)