- Mayflies

_Eggs, Larva, subimago, adult

- lamellate gills along abdomen 

- well developed legs

-Perpendicular wings on adults

- dragonflies and damselflies

- predacious

- no external gills

-longer body on damselflies (wings up)

- dragonflies cannot pull back their wings 

- stoneflies

- have 2 filaments

- no lamellate gills along abdomen

- some have filamentous gills

- adult wings are flat

- mostly shredders or grazers 

- caddisflies

- have anal prolegs with hook

- less visable antennae

- only order that makes cases

- adult wings lay down, very hairy

- true bugs

- egg, nymph larae, adult

- predacious "beak"

-wing pads

- wings fold over each other

- beetles

- egg, larva, pupa, adult

- larva very different from adult

- adults- have hard case on body that does not overlap

- adults have chewing mouthparts

- larva- undeveloped eyes, sometimes have tusks

- alder flies, dobsonflies

- mouth has large, chewing pinchers (predacious)

- abdomen has strand-like appendages extending from each side

- three pairs of segmented legs on middle section of body with tiny pinchers at the end of each

- each segment contains filaments for respiration 

- abdomen ends with two elongated appendages or prolegs

- midges, mosquitoes, gnats, flies

- elongate body

-segmented body

- most species rich order (includes chironmidae)

- adults have one pair of wings

- very diverse morphology 

- flatworms are ciliated, soft bodies animals

- bodies are solid aside from an incomplete digestive cavity

- many species are parasitic 

- others are free living (marine, freshwater, moist terrestrial)

- second in diversity only to arthropods

- include snails, slugs, clams, octopuses, and others

- some have a shell, some do not 

- segmented worms 

- body built of repeated units

- allows for specialization 

- Class oligochaeta ( earthworms, many segmented aquatic worms)

- Class hirudinea (leeches, mainly freshwater, usually flattened dorsoventrally, hermaphroditic and cross-fertilization, suckers on both ends of bodies, some eat detritus, some suck blood)

- most successful animals 

- affect all aspects of human life

- divided into four extant classes (chelicerta, crustacea, hexapoda, myriapodia) 

- largely marine, some freshwater

- crabs, shrimps, lobsters, barnacles, crawdads, copepods, pill bugs, sand fleas

- have three tagmata; cephalon and thorax fused to form cephalothorax

- 2 pairs of antennae, 3 pairs of appendages for chewing, and various pairs of legs (most appendages are biramous)

- orders: amphipoda, ostracoda, isopoda, decapoda

insects are by far the largest group of animals

- more than half of all named animal species 

- approximately one billion billions insects are alive at any one time 

- three body regions (head, thorax with three segments, each with a pair of legs, abdomen)

- many insects undergo metamorphosis

- single metamorphosis (mayflies): immature life stages similar to adults

- complete metamorphosis (caddisflies, true flies): immature larva are wormlike, a resting stage (pupa or chrysalis) precedes the final molt into adult form

- seperated into two clades: spiralia and ecdysozoa 

- spiralia has platyhelminthes (platyzoa), annelida and mollusca (lophotrochozoa) 

- ecdysozoa has nematoda and arthropoda 

- Physical

- Chemical

- Biological

- temperature ( temperature affects metabolism, and if temperature is incompatible, bugs can't survive.)  

 - light (light can affect temp. and photosynthesis levels in aquatic plants, plant biomass produced in system is autochthonous, biomass produced out of the system (falling leaves from trees) is allochthonous. Light determines food base and whether the majority of food is auto or allo. 

- water current (can directly bring food to insect or dislodge insect from hiding place, making it prey. some insects have special adaptations to survive strong currents) 

- substrate (is extremely important, provides shelter for bugs, different substrate material produces different habitats for different species, firm substrate can grow algae which some species use as food.) 

- Oxygen (insects breath dissolved oxygen from the water, water doesn't hold oxygen very well, species with high oxygen requirements need specialized areas or adaptations.)

- Acidity (concentration of H+ ions. most invertebrates need a neutral environment)

- Alkalinity (measure of all compounds that can shift pH into alkaline range, measure of how well it can avoid becoming acidic (buffering capacity) 

- Hardness (measure of all cations in water, high cations means hard water, invertebrates like slightly hard water for unknown reasons)

- Nutrients ( phosphorus and nitrogen impact invertebrates. A change in their levels could cause eutrophication (too many nutrients, too much plant growth) which can cause environment to become inhabitable for some insects) 

-  Food (plant material serves as substrate, as well as complex substrate is habitat and hiding places. animals are consumers and the type of food they eat influences where they live. some species can turn large bits of coarse detritus into smaller pieces which can shape the substrate)

- Competition and Predation ( intraspecific competition is between two individuals of the same species, interspecific is two species competing. competition affects what survives there, if a species gets out competed. predation can lead to an increase in biodiversity (keystone species), both process are healthy for an environment, but can be twisted by human interference (introduced species can throw natives out of balance and drive them out completely). pollution can affect water quality and what can live there

- -they can shape the environment where they live due to eating detritus and changing substrate

, -they are the prey for many aquatic species, which in turn means they impact what can live there

- used to assess health of a water system, called biomonitering

-  useful to humans as food and recreation (flyfishing)