non-insect arthopods Flashcards
what class and order are mites
- class: arachnida
- order: acari
describe the structure of mites
- small (less than 1 mm)
- one body part w a small head area attached to body
how many species of mites are there
- 50 000 described
- estimated >1 000 000 in the world
how to adult and nymphal mites differ
- adults 4 pr legs
- nymphs 3 pr legs
whats stage of decomposition do mites arrive for
later stages
where do we tend to find mites
in soil beneath remains
how do mites disperse
- phoresy
- ie. carried by other insects
describe forensic relevance of mites
- some families consume fungus and rotting veggies
- predatory on fly eggs and first instars (can alter/ delay successional patterns of decay)
- indicate possible origins of a corpse (think: theyre in the soil… which soil)
where are Cunaxidae found
- theyre a kind of mite
- commonly in compost
describe the collection of mites
- difficult to see and collect
- we take soil samples under the corpse
- use a heat lamp and a funnel, the mites fall through the funnel into a collecting jar
describe the structure of spiders
- 8 legs
- 2 body parts: abdomen and cephalothoraxx
what order are spiders
araneae
describe what kind of species spiders are
- predatory on insects and other arthopods
- corpses are a source of insect prey
what order are pseudoscorpions
pseudoscorpionida
describe the structure of pseudoscorpions
- small (<5mm)
- 2 body parts: abdomen and cephalothorax
- pedipalps and mouthparts distinctive, puncher like (called chelate)
- 8 legs (4 pairs)
when do we find pseudoscorpions
- late stage decay
- they’re predatory on other arthopods
what class and order are sow bugs or pill bugs
- class: malacostraca
- order: isopoda
when are sow bugs or pill bugs found
- all stages of decomposing remains
- better identifier of location than time of death
how many species of sow bugs or pill bugs are there in ontario
13 (most are not native)
what class are centipedes
chilopoda
what is the forensic relevance of centipedes
some are found largely inside, other largely outside
how many species of centipedes are there in canada and alaska
70
what class are millipedes
diplopoda
where would we find millipedes
moist habitats
what is the forensic relevance of millipedes
- indicators of habitat
- like moist areas
- eat plants but also on decomposing animal tissue
how many species of millipedes are there in canada and alaska
> 60
what is the class name for insects
insecta
what order are cockroaches
blattaria
what is the forensic relevance of cockroaches
- feed on decaying corpses (typically later-stage)
- nocturnal household pests
what order are earwigs
dermaptera
what is the forensic relevance of earwigs
- damp habitats
- commonly beneath a corpse as daylight shelter area
- predatory
what order are beetles
coleoptera
what family are predatory beetles
staphilinidae
when do predatory beetles arrive
- early after death
- remain throughout rotting cycle
when do scarab beetles arrive
- commonly after 1-2 days
- can be as soon as 15 mins tho
what is the family name for ground beetles
carabidae
when do ground beetles arrive
- early
- remain throughout rotting period
when do histerid beetles arrive
- in very large numbers
- feed on maggots
- stay throughout decomposition period
what family are burying beetles
siphidae
when do burying beetles arrive
- early
- stay throughout decomp
- larvae and adults will be found in corpses
do silphidae larvae feed on remains or maggots or both
- authors cannot agree
- some say one, and not the other, some say both
what beetles are present during early stage of decomp
- predatory
- scarab
- ground
- histerid
- burying
what family are carpet beetles
dermestidae
what family are museum beetles
dermestidae
what do dermestidae feed on
- dried skin
- hair
- larvae
- adults
what is the forensic relevance of dermestidae
identifying location, not necessarily associated w corpses
what order are caddisflies
trichoptera
where do immature caddisflies live
live in cases made of sand, twigs, or leaves
where do we find caddisflies
- underwater/ aquatic habitats
- rapidly consume submerged corpses and decaying matter
true/false identifying underwater specimens is similar to land specimens
- false
- typically a specialist (an aquatic entomologist) is needed because of how different it can be
what is an example as to why aquatic specimens need to be handled by specialists
- red bloodworms (chironamidae, midges) were recovered form a corpse in a river
- mididentified as carpet fibres
what family are mayflies
ephemeroptera
what order are flies
diptera
what is a specimen that looks like a fly w 4 wings
not a fly
describe the structure of flies
- 2 wings
- hind wings reduced to haltereses
which of the following are flies: blow flies, butterfly, dragonfly, house fly, dragon fly
- blow flies
- house fly
- dragon fly
- any with 2 word names
which flies are first to arrive in cooler climates
calliphoridae (blow flies)
which flies are first to arrive in warmer climates
sarcophagidae (flesh flies)
where do blow flies deposit and what
- deposit eggs
- in folds, eyes, ears etc
where do flesh flies deposit and what
- deposit larvae
- in folds, eyes, ears etc
true/false some blow fly maggots are predatory to other maggots
true
what is the main role of blow flies
to consume carrion
what is the family name of cheese skippers
piophilidae
where do we tend to find cheese skippers
- stored products and dried foodstuff
- associated with slaughter houses and tanneries
true/false maggots are often found in graves
- true
- found in 10% of graves 3-10 years old
- found in egyptian mummies too
true/false maggots can’t jump
- false
- they can jump up to 3 inches to escape predators
- also to migrate to pupate away from corpse
true/false maggots don’t react well to heat
- false
- they can tolerate up to 54 C for 1 hour and 45 C for 24 hours
what goes through simple or ametabolous developmentand what is it
- silverfish, and other primitative insects
- its a gradual increase in the size of the young until adult dimensions are attained
what goes through incomplete or hemimetabolous metamorphosis and what is it
- earwigs
- larvae are similar to adults but missing some structures like wings
what goes through complete or holometabolous metamorphosis and what is it
- most insects, including beetles and flies
- distinct immature stage (like maggots or grubs) and then pupae and adult
which instars do keys exist for
- most for 3rd
- some 2nd
- very few egg or 1st
how do we identify instar
- based on posterior paired spiracles
- either 1, 2, or 3 openings
how do blow fly larvae emerge from the egg casing
they split the egg along the length at the plastron (p is plastron… the midline)
how do adult flies emerge
- break open the pupae with a specialized temporary structure called a ptilinum
- swelling on the head breaks pupal case
- the fly emerges, ptilinum shrinks, fly exoskeleton hardens
what happens if there is damage to the exoskeleton as the fly is emerging from the pupa
a scar will be produced
