Lecture 9

Question 1

What order are ground beetles in?

Answer 1

coleoptera

Question 2

what is unique to the beetle order coleoptera?

Answer 2

have elytra: hardened forewings for protection

unique to this order

Question 3

what type of mouthparts do beetles have?

Answer 3

biting chewing

Question 4

what type of development do beetles have?

Answer 4

holometabolous

Question 5

what family are ground beetles in?

Answer 5

carabidae

Question 6

where is the elytra attached & what does it cover?

Answer 6

attached to the pro-thorax

cover the abdomen, meso-thorax & meta-thorax

Question 7

what is unique about the ground beetle?

Answer 7

5 tarsal segments on all legs

thread-like antennae with 11 segments

Question 8

describe the elytra of Chlaenius cordicollis

Answer 8

have fine hairs - unique

Question 9

describe the colouring of Chlaenius cordicollis

Answer 9

very shiny when young, become darker with age - shine wears off when pushing through rocks

Question 10

what is the location of ground beetles?

Answer 10

MB & east Minnesota to the Atlantic coast

Question 11

describe the habitat of Chlaenius cordicollis

Answer 11

lakeshores & river banks with limestone slabs

Question 12

describe the activity of Chlaenius cordicollis during the days & nights

Answer 12

days - hide in grps under slabs

night - active on the surface

Question 13

how do males & females differ in Chlaenius cordicollis?

Answer 13

female legs - narrow

male legs - broader, brush-like segments enabling them to hold on & grip to a female when mating

Question 14

describe the eggs of Chlaenius cordicollis

Answer 14

Unprotected when deposited

Eggs are cemented singly to a stone (occasionally 1-2 together)

Question 15

describe the larvae of the ground beetle

Answer 15

head is the only hard part

soft tissue = growing, almost done instar

sclerites

Urogomphi

Question 16

how many instars to ground beetles have?

Answer 16

3

Question 17

sclerites

Answer 17

hard plates with soft cuticle b/w them on the thorax & cuticle

larvae

Question 18

Urogomphi

Answer 18

extended segment at the posterior of the abdomen, function uk but believed that’s used for communication

Question 19

the larval instar can be determined by the ______

Answer 19

measurement of a sclerotized organ

Question 20

dyar’s rule

Answer 20

the ratio of dimensions of sclerotized organs (head, spiracles etc.) of adjacent instars of immature insects is relatively constant

Question 21

describe the pupa of a ground beetle

Answer 21

can see mandibles & legs

cuticle begins to harden & the beetle gets darker

Question 22

what is the name of the PRO that hardens & darkens in the cuticle?

Answer 22

sclerotin

Question 23

describe the teneral adult stage in the first 12 hr period

Answer 23

Elytra – white

Head capsule not darkened

Question 24

describe the teneral adult stage in the first 30 hr period

Answer 24

Head capsule darker

Mandibles are hard enough to break up food & function properly

Wings are present but not hardened, therefore cannot use for flight

Question 25

describe the teneral adult stage in the first 3 days

Answer 25

Insect appears like an adult Still can’t fly (wings are still soft) 2 weeks from this time when they can fly

Question 26

what can a ground beetle fly?

Answer 26

weeks from the 3 day teneral adult stage

Question 27

how long does it take for the larval instar stages to be completed?

Answer 27

30 days

Question 28

teneral adult

Answer 28

adults that can't fly

Question 29

when do the beetles mate?

Answer 29

June-July

Question 30

what stage has never been observed in nature?

Answer 30

pupa

Question 31

how long is the egg stage?

Answer 31

7 days

Question 32

how long is the pupa stage?

Answer 32

9 days

Question 33

describe the eating behaviour

Answer 33

scavenger insects (usually don't attack live prey) lakes act as conveyor belts feeding the beach-dwelling insects

Question 34

what do the ground beetles feed on that the lake washes up on shore?

Answer 34

Insects falling in the lake when trying to fly Feed on fish flies that wash up when emerging from the bottom of the lake

Question 35

Mid-summer diet is dominated by _____

Answer 35

fish flies

Question 36

when the ground beetles feed on the fish flies, what are they eating in particular?

Answer 36

dead adults exuviae from emergence blowfly larvae feeding on the above (what's flying)

Question 37

in ____ adults disappear from the beach

Answer 37

early or mid-Sept

Question 38

Adults move to the top of the beach by mid-Sept - why?

Answer 38

Temp in Sept lowers, therefore their metabolic rate does as well They can’t run as fast & outrun the waves like they do in the spring & summer If they aren’t well up the beach at this point then they’re at risk of drowning

Question 39

what is a mechanism of freeze avoidance in ground beetles ?

Answer 39

cease feeding in Sept & gut is empty

Question 40

average freezing point?

Answer 40

-2C

Question 41

average supercooling point?

Answer 41

-4C

Question 42

lowest supercooling point?

Answer 42

-7.6C

Question 43

how do you know when a female ground beetle is in a reproductive state?

Answer 43

have distended abdomens cuticle is separated from the abdomen

Question 44

what cue initiates reproductive physiology?

Answer 44

day length

Question 45

what day length did they start to see females in their reproductive state?

Answer 45

17hr