Benthic Macroinvertebrates

Phylum Annelida Worms found in soft mud bottoms, and in high numbers are considered indicators of very poor water quality.

Phylum Annelida Leeches

Phylum Arthropoda Class Malacostraca Order Decapoda Crayfish Reproduction: females carry eggs in a  mass underneath their tail, which resembles a large "raspberry.“ Food: omnivorous, eating plants and animals; pinchers are used for tearing food into edible chunks; crayfish are preyed upon by larger game fish.

Indicator of Crayfish Indicator Role: Indicates moderately clean water; seldomly found in polluted waters.

7 Levels of Classification Keep Kingdom Plates Phylum Clean Class Or Order Family Family Gets Genus Sick Species

Kingdom: Animalia Phylum: Arthropoda (jointed-foot invertebrates) Class: Insecta (insects) Order: …

Orders Ephemeroptera: mayflies Plecoptera: stoneflies Odonata: damselflies and dragonflies Megaloptera: alderflies, dobsons and fishflies Hemiptera: true bugs, ex. Water strider, water boatman, backswimmer, water scorpion, and giant water bug. Trichoptera: caddisflies Diptera: true flies, ex. Cranefly, blackfly, midgefly Coleoptera: beetles, ex. Water penny, whirligig beetle, predaceous diving beetle

Order Plecoptera Stone fly nymph Nymphs: possess two distinct "tails" called cerci, which are actually sensory feelers; brightly colored in tan, brown, gold, and black; length varies, up to 1 inch. Reproduction: females deposit eggs on top of water where they drift down to the bottom.

Stonefly Nymph Food: some stoneflies are carnivorous, others feed on algae, bacteria, and vegetable debris; eaten by a variety of fish species. Indicator Role: Indicates ample supply of oxygen, important food for coldwater fish such as trout. One of the indicator species used to indicate cleaner waters.  Mostly found in the swift flow of stream riffles.

Caddisfly (Trichoptera) Build homes Cases are built from sand, twigs, small stones, crushed shells, rolled leaves, and bark pieces; cases used for protection and pupation: length up to 1 inch. Food: larvae feed on algae, small bits of plant material, and animals; some species build nets where they catch drifting food; fed upon by several species of fish. Indicator Role: Caddisflies represent a large range of pollution tolerance.

Mayfly (Ephemeroptera) three distinct cerci (tails), occasionally two; cerci may be fuzzy or thread-like, but never paddle or fan-like; color varies from green, brown, gray, but usually black; total length up to 1 inch. Food: consists of small plant and animal debris, such as algae, diatoms, and plankton; preyed upon by fish and play an important role in the food chain. Indicator Role: mayflies display a varied tolerance to pollution, but are generally considered cleaner water benthos. 

Metamorphosis Stonefly : egg – nymph – adult Caddisfly: egg – larva – pupa – adult Incomplete metamorphosis: three changes Complete metamorphosis: four changes

Alderflies (Megaloptera) Food: larvae are aggressive predators, feeding on other adult aquatic  macroinvertebrates; as secondary consumers, they are eaten by other larger predators. Indicator Role: Alderflies are generally intolerant of pollution.

Dobsonfly (Megaloptera) Food: predaceous larvae feed upon other aquatic macroinvertebrates;  larvae widely used as fish bait; important food source for larger game fish. Indicator Role: dobsonfly larvae are considered fairly intolerant to pollution

Water Penny (Coleoptera) Food: primarily plant debris such as algae and diatoms. Indicator Role: indicates ample supply of oxygen, and fast flow of water.

Riffle Beetles (Coleoptera) Food: primarily plant material such as diatoms and algae. Larvae: resemble small "torpedoes" with circular stripes or rings around body; pointed at both ends with a "fuzzy" mass at one end; color usually grayish; length less than 1/2 inch. Indicator Role: found in fast-moving waters, indicates ample oxygen supply

Damselfly Nymph (Odonata) Food: predaceous, nymphs feed on other aquatic macroinvertebrates. Indicator Role: Variable, with damselflies inhabiting slower moving waters, margins of streams, ponds, and lakes.

Dragonfly Nymph (Odonata) Food: predaceous, nymphs feed upon other aquatic macroinvertebrates, small fish, and tadpoles Indicator Role: Dragonflies are found in slower moving streams and in ponds, often reflecting waters with lower dissolved oxygen levels. 

Black Fly (Diptera) Food: larvae eat organic debris filtered from water; adult females of many species feed on blood. Indicator Role: Black flies are found under rocks in swiftly flowing streams, but also sometimes indicate too many nutrients (nitrogen and/or phosphorus) in the water.

Crane Fly (Diptera) Food: mostly plants and plant debris; some are predaceous. Indicator Role: Indicates moderately clean water; seldomly found in polluted waters.

Midge Fly (Diptera) Food: primarily algae and other organic debris; many feed on other insect larvae. Indicator Role: Many midges, such as the blood worm Chironomus, are indicators of poor water quality and tolerant of pollution.

Water Scorpion (Hemiptera) Their name comes from their specialized grasping forelimbs, similar to the anterior 'pincers' of scorpions, and an elongate caudal siphon or breathing tube, which conjures up the image of the scorpion's long stinging tail.

Whirligig Beetle (Coleoptera) Life Cycle: Pupation occurs in cocoons on plants or on the shore. Adults feed on organisms on the water surface or by scavenging debris.

Backswimmer (Hemiptera) predator swim upside-down

Giant Water Bug (Hemiptera) like slowly moving water. They usually grab hold of a plant near the surface, and stick their short breathing tube out of the water to allow them to breath while waiting for prey. With their powerful front legs they are able to grab other bugs and prey as big as small fish, frogs and salamanders. They pierce their prey with their sharp beak and secrete enzymes that dissolve the body tissues, thus allowing them to suck up the resulting liquid.

Predaceous Beetle (Coleoptera) These predaceous insects feed on a variety of aquatic organisms, including small fish.

Water Boatman (Hemiptera) Their sucking mouthparts are modified to allow some chewing.  Water boatmen often swim in open water. They can be seen in groups or clusters swimming through a pond. They feed on plant material, including algae.

Water Strider (Hemiptera) They feed on a variety of aquatic invertebrates including seed shrimp and mosquito larvae that rise to the surface, and insects that drop into the water. The Water Strider has a piercing, sucking mouth. It pushes its mouth into the insect prey and sucks it dry. It can locate its prey by feeling the smallest movements or vibrations made in the surface of the water.

Hemiptera Backswimmer

Hemiptera Giant water bug

Coleoptera Predaceous Beetle

Hemiptera Water strider

Coleoptera Whirligig beetle

Hemiptera Water boatman

Odonata Damselfly nymph

Odonata Dragonfly nymph

Ephemeroptera Mayfly nymph

Plecoptera Stone fly

Megaloptera Dobsonfly

Coleoptera Riffle beetle larvae

Diptera Black fly larvae

Diptera Crane fly

Diptera Midge fly larvae

Hemiptera Water scorpion

Megaloptera Alderfly

Trichoptera Caddisfly larvae

Coleoptera Water penny