Lesson 2 - Page 1



Order Orthoptera Grasshopper , Katydid 
Order Hemiptera Bug ; Stink bug 
Order Homoptera Cicada  leafhopper 
Order Hymertoptera bee; wasp 



hese are one of the largest group of flies. The larvae tend to be oblong, cylindrical and somewhat tapered toward the head. The head is retractable and only partially hardened. True flies lack jointed legs. Some have complete, exposed head capsules; others have a reduced retracted head. The bodies are soft and flexible.


Order Trichoptera

All caddisflies have hard-shelled head capsules. Sometimes the first three segments behind the head also have hard-shelled plates on the top surface above the attachments for three pair of legs. The rest of the body is soft and often cylindrical. The larvae possess two small hooks on the last segment. Some species are free-living while others make case retreats out of silk, sand grains, pebbles, or bits of plant material. 

Caddisflies undergo complete metamorphosis and the larvae transform into winged adults in the water. As adults, caddisflies only live a few days and do not eat at all.several finger-like lobes

Order Plecoptera

Stoneflies are indicators of good water quality because the nymphs require highly oxygenated water. They tend to inhabit clear cold streams, and are highly intolerant of changes in water quality. 

Stoneflies undergo incomplete metamorphosis. The aquatic nymphs transform directly into winged adults. The heads and top surface of the first three body segments on nymphs are hardened. Their antennae are moderately long to long, and all species have exactly two tail filaments.

Stonefly nymphs have gills around the base of their legs or no gills at all.

Order Ephemeroptera

Mayflies are usually easy to identify. The nymphs can be small and squat, or long and slender. They have three pairs of segmented legs and visible antennae. They are most easily identified by their three tail filaments (although they may have 2), and by the seven pairs of abdominal gills found on most species. The gills may be either flat and spade shaped, or feathery in appearance.

Mayfly nymphs are often flattened or streamlined to reduce the force of fast currents. They are most abundant in clear streams, though a few kinds may be found in other habitats. 

Order Coleoptera

Largest order of insects representing about 40% of known insect species. About 1000 of the approximately 30,000 species are aquatic. All beetles go through complete metamorphism. 

Order Odontata

Dragonflies and damselflies are predators, easting anything they can catch including other odontates. . The order name is derived from Greek word tooth, which refers to the toothed apparatus. Their nymphs are abundant on the bottom of slow moving waters. They may be elongated and are a somber gray, green, or brown color. The adults have two parts of winds of equal length with large compound eyes, and reduced antennae. They have 10 segmented abdomen. The dragonflies are robust, and perch with wings spread. Damselflies have a long slender abdomen and wings are usually flat when perched.


Moths and butterflies belong to the group called the Lepidoptera. They are medium to large sized insects with mouthparts reduced to form a coiled tube for sucking liquid food. They have antennae that are long and often feathery. They have large compound eyes with two pairs of large and showy wings. Wings have overlapping scales and moths are often hairy. The abdomen or stomach parts have ten segments. Butterflies which sleep at night, have slim bodies and clubbed antennae and rest with wings folded over their back, the hind wings almost covering the forewings. Moths, which are awake at night, never have clubbed antennae and rest with the wings in various positions.

Metamorphosis is a rapid transformation of life that some animals undergo from juvenile stage to the adult form. Metamorphosis is characteristic of amphibians but butterflies and moths also undergo change due to hormonal control. The life of a butterfly is a little different than that of a moth. Moths and butterflies go through four life stages: egg, caterpillar, pupa, and adult. The length of the life cycle varies from species to species.

Butterflies and moths both lay eggs which hatch into caterpillars of different shapes and sizes depending on the species. The caterpillar feeds usually on leaves and grows very rapidly. It molts (sheds) its skin and develops a new one as the body grows. The metamorphosis begins when the caterpillar uses silk to attach to a plant. The skin hardens to form a chrysalis (for a butterfly) a cocoon for a moth. Within the chrysalis and the cocoon the caterpillar changes to the butterfly and moth respectively. In the adult stage the main purpose is to eat and to lay eggs. Butterflies and moths usually only live for several weeks.



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