Aquatic Insects

• What are aquatic insects?

  A polyphyletic ecological assemblage of taxa

  Aquatic insects have arisen many times in evolution

  
• What stages are aquatic insects?

  Usually young instars, adults are wings and terrestrial
• What percentage of insects are aquatic?

  3%

  species from 14 different orders inhabit nearly every body water. Mostly dipterans
• What do aquatic insects have?

  Air-filled tracheae

  Phylogeny

  Many respiratory methods

  Fossil Evidence

  
• What problems do open water species have?

  Osmoregulation amd dehydration issues
• What problems do open water species have?

  Oviposition sites are limited, diets are not well known
• Major entirely aquatic species?

  Ephemero

  Odonata

  Pleco

  Tricho

  Megalo
• What are the species with aquatic life stages?

  Hetero (larvae + adult)

  Coleo (larvae + adult)

  Dip

  Neuro

  Collembola (larvae + adult)
• What problems do aquatic macroinvertebretes face?

  Food avaliability

  Water Characteristics

  Abundance of other organisms

  Substrates
• Lotic Environment? (flowing water)

  Water influences substrate type, transport of food, and levels of dissolved O2
• Lotic Environment Adaptations? (flowing water)


  Flattened body

  Suckers and hooks

  Uses silk for drift nets

  Small body

  Burrows
• Lentic Enrionmental Adaptations? (still water)

  Use surface meniscus

  Larger bodies

  
• Lentic water?

  O2 diffusion is slow

  Warm waters can have less oxygen or be anaerobic
• Shredders?

  Live on dead plant tissue or course matter
• Collectors?

  Feed on organic matter that settle
• Scrapers?

  Graze on solid surfaces, chisel like mouthparts
• Piercers?

  Feed on plants, algae, or animal fluids with chisel like mouth parts (hemiptera)
• Predators?

  Parasites + predators
• What is the river continuum concept?

  As a river size increases the forest's influence decreases
• What are the adaptations of insects that use temporary bodies of water?

  Dessication resistant eggs

  Rapid egg laying in new water, rapid development
• Applications of aquatic entomolgy?

  Food web dynamics

  Effects of perturbation and pollution
• Application of aquatic entomology?

  Water quality monitering

  Bioassays to determine toxilogical impacts
• What is EPT taxa?

  Ephermeroptea. plecoptera, trichoptera

  Sensitive species composition can indicate water quality

  
• Importance of hexagenia? (burrowing mayflies)

  Burrowing can double the rate of non-water soluable toxins that are found in the sediment

  
• What are the important of aquatic insects to humans?

  Fish diets, and the conversion of plants into biomass
• What are the important of aquatic insects to humans?

  Pests and vectors, have many aquatic larvae

  Biting flies and mosquitoes are a large problem
• Is 1/6th of the population almost always affected by a fly borne illness?

  Yes
• What are the other uses of aquatic insects?

  Biological controls in controlling weeds