ENTM 335 Lab Exam 1

Two general types of insect collection

Active and passive collection

Active collection is…

… collection methods where you actively search for insects

Methods of active collection are…

… Hand collecting, netting, flipping objects

Passive collection is…

… Setting a trap and waiting for insects to enter

Methods of passive collection are…

… Light traps, Malaise traps, Berlese traps, and Pitfall traps

A trap that attracts insects with specific spectrum of light (UV/Blacklight)

Light Trap

A flying insect trap

Malaise trap

A trap that collects small arthropds from soil or leaf litter

Berlese trap

A trap placed in the ground so insects fall in

Pitfall trap

A mesh aerial net is useful in…

… soft vegitation and in the air

A sweep net is useful in…

… thorny vegitation and trees

A aquatic net is useful in…

… water. has a thick canvas with mesh at the end

A beat sheet collects…

… insects knocked from vegitation

A small aerial net is useful for…

… insects with greater speed, such as flies

A large aerial net is useful for…

large capture radius, help capture dragonflies

What liquid is used in pitfall traps?

Propylene glycol

Ethylene glycol should be avoided in pitfall traps because…

… it is dangerous to wildlife

Issue with pitfall trap…

… mammal by-catch

What are soft forceps used for?

Catching and placing insects in ethanol vials

What are hard forceps used for?

in-lab curation work

Kill jar chemical

ethyl acetate

What speciemns are commonly preserved in ethanol?

Aquatics, immatures, soft-bodies

Ethanol concentration for preservation is…

… 70%

Ethanol concentration used for DNA extraction…

… 90%

Drawback of 95% ethanol is…

… it dries out speciemen

Insects are pinned through…

… vertically through the mesothorax, slightly right of the midline

Why pin through the mesothorax?

Thoracic muscles dry around the pin

Why pin to the right of the midline?

Preserved bilateral symmetry and characteristics

How much pin should remain above a pinned insect?

¼ of the pin

What pin size is typically used for pointing?

#3

Why stainless steel over enamel pins?

Resists corrosion

The disadvantage of glue boards…

… the speciemn’s underside is obscured

Why should microlepidoptera be spread?

Can’t identify without spreading

Dried speciemens can be relaxed by…

…humid chamber, ammonia water, injecting with hot/ammonia water

What is the minimum information on a locality label?

Country, state, county, locality, date, and collector

Top label has…

…locality

Middle label has…

…additional info

Bottom label has…

…ID

A microscope used for larger specimens…

…dissecting microscope

A microscope used for slide-mounted specimens…

… compound microscope

How long is a Berlese sample left under a light?

About 3 days

The solution used to clear specimens before slide mounting is…

10% potassium hydroxide (KOH)

How do you make 10% KOH?

1 KOH pellet per 10 mL of water

How long are specimens normally left in KOH?

12-24 hours, 72 if large

Two options after removing speciemns from KOH are…

… return to ethanol or immediately stain and slide mount

How are cleared speciemens stained?

One drop of double stain for 5 minutes

What is used to rinse specimens after double staining?

70% ethanol

The mounting medium used for class slides is…

… PVA mounting medium

How long should mounted slides stay on the warming table?

At least one week

Different supplies used for insect curation…

pins, points, glue, foam board, spreading board, cardstock, pinning block, vials, ethanol

Pros of dry preservation

Easy to observe

Cons of dry preservation

Fragile, pests, needs special preserving needs (cabinets, trays, etc)

Pros of liquid preservation

Keeps specimen flexible, preserves internal tissues

Cons of liquid preservation

Evaporates, color issues, vials take up space

Pros of slide mounting

Durable, examine tiny structues

Cons of slide mounting

only works on very small speciemen, 2-D view only

Keep speciemen if…

… they are in good condition and have a good label

No antennae, no eyes, front legs act like antennae, tiny, soil-dwelling, wingless

Protura

furcula used for jumping, wingless, collophore (tube-like organ) on abdomen

Collembola

two cerci, long antennae, no eyes, wingless

Diplura

Jumping bristletail. 3 tail, large eyes, arch body, wingless

Archaeognatha

silverfish. 3 tail, flat body with scales, wingless

Zygentoma

Mayflies. 2-3 tails. triangular wings upright, aquatic immature, adult life short lived

Ephemeroptera

Dragonfly & damselfy. large eyes, 2 pair long wings, predatory, aquatic immatures

Odonata

stonefly. 2 cerci. wings fold flat, aquatic immature, clean water

Plecoptera

Earwigs. curved cerci

Dermaptera

very small, looks like termite, could be winged or wingless, beaded antennae

Zoraptera

webspinners, enlarged front tarsi

Embioptera

mantis. raptorial front legs, elongated prothorax, traingle head

Mantodea

leaf insect. long slender body

Phasmatodea

Ice crawler. wingless, elongated body, long antennae, cold habitats

Notoptera

Grasshopper, crickets, katydid. enlarged hind legs, leathery forewings, chewing mouthparts

Orthoptera

cockroach + termite. flattend body, long antennae, pronotum covers head

Blattodea