Hemipteroid orders

Question 1

what are the Hemipteroid orders

Answer 1

• Phthiraptera – lice
• Tysanoptera – thrips
• Hemiptera – bugs (huge order)

Question 2

hemipteroid orders - what do they all have in common

Answer 2

• Hemimetabolous (no pupa)
• All have piercing sucking mouthparts

Question 3

hemipteroid - piercing sicking mouthparts

Answer 3

• Spit digestive enzymes, wait for food to get soft, then suck it up
• there are three broad uses
• there are three independent evolutions of human blood feeding in the Hemipteroids

Question 4

hemipteroid orders - uses for the piercing sucking mouthparts

Answer 4

1. Suck plant fluids (sap)
2. Attack prey, suck out nutrition
3. Suck blood

Question 5

hemipteroid: piercing sucking mouthparts - which organisms show independent evolutions of human blood feeding

Answer 5

• Pthiraptera
• Triatomes (Reduviidae, Hemiptera)
• Cimicidae (Hemiptera)

Question 6

Phthiraptera

Answer 6

• Lice
• All parasitic on veterbrates
• Wingless
• Piercing mouthparts for sucking blood from mammals (even marine mammals)
• Claws adapted to grasp hair; eggs cemented to hair (‘nits’)
• Most mammals have species specific lice parasites

Question 7

phthiraptera - what species of lice do humans have?

Answer 7

• Head
• Pubic (‘Crabs’)
• Body (only one that is a disease vector)

Question 8

phthiraptera: human lice - why are body lice disease vectors

Answer 8

their piercing mouthparts spit saliva that transmits disease from someone else that had typhus

Question 9

Hemiptera

Answer 9

• true bugs
• Name means “half wing”
• Forewings of suborder Heteroptera have a base that is thick and leathery and a distal end that is membranous

Question 10

Hemiptera - key features of Hemipteran biology

Answer 10

• All-fluid diet ingested through piercing-sucking mouthparts
• Two canals: deliver saliva in, suck food out

Question 11

Reduciidae

Answer 11

• assassin bug
• Predators of other arthropods
• Exception: Triatominae subfamily feeds on blood
• Some species transmit Chagas disease in tropics

Question 12

Reduciidae - how can they use their mouthparts

Answer 12

1. predatory (pierce, externally digest and suck prey)
2. Phytophagous (pierce plant, suck sap)
3. Parasitic (pierce skin, suck blood)

Question 13

Gerridae

Answer 13

• water striders
• elongated body
• Long legs
• Predators of insects on water surface

Question 14

Gerridae - how do they move on the water

Answer 14

• Hydrophobic hairs on front and rear legs let them ride surface tension
• Use middle legs like oars to move

Question 15

Pentatomidae

Answer 15

• stink bugs
• Stinky cyanide-based defensive fluid (but other Hemiptera families have it too)
• Characteristic shape, prominent scutellum (not on similar shield bugs)
• Most are plant feeders

Question 16

Cimicidae

Answer 16

• bed bugs
• Suck blood from mammals and birds
• Wingless
• Don’t transmit disease to humans
• Transferred typically through furniture
• Can live >year w/o food – resistant to starvation

Question 17

Cicadidae

Answer 17

• cicadas
• Annual come out every year (but take >1 year to develop)
• Loud species-specific song
• Periodic cicadas (genus Magicicada): 13- and 17-year cycles
• they swamp their predators

Question 18

cicadidae - how do they swamp their predators

Answer 18

• Predators take advantage of the swarm and eat them.
• predators then get full and the cicadas that survive can reproduce

Question 19

cicadidae - explain mating and reproduction behavior

Answer 19

• Brood feed on plant roots, then mass emergence to mate
• then they oviposit in branch
• after, nymphs drop to soil, burrow, feed on roots

Question 20

What is the similarities between mayflies and cicadas and why are locusts different

Answer 20

• Mayflies and cicadas : Coming out for a brief time and coordinate their mating bc they both live short lives. Some extent overwhelms predators
• Locusts: Swarming bc they overeaten their food source

Question 21

Aphidae

Answer 21

• aphids
• Winged and wingless, sexual and parthogenetic (developmental plasticity)
• Can damage plant through feeding
• Distinguished by cornicles
• Produces honeydew as a sugary excrement
• mutualism with ants

Question 22

Aphidae - explain the mutualism with ants

Answer 22

• aphids are tended by ants for honeydew
• ants protect aphids form predators, in return they get honeydew

Question 23

Problems associated with feeding on sap

Answer 23

1. Too much water and sugar (“dinking from a fire hose”). Honeydew excretion = sugar water
2. Not enough other nutrients (also applies to blood feeders, except for sugar part)

Question 24

solutions to problems associated with feeding on sap

Answer 24

1. Filter chamber: get sugar and water out of gut quickly and in large quantities to focus on micro-nutrients
2. Symbiotic micro-organisms: house microbe factories to produce what you want

Question 25

solutions to sap feeding - filter chamber

Answer 25

- they filter out most water and sugar in “first pass” - Let rest go through the full digestive tract - Can concentrate other nutrients up to 10x

Question 26

solutions to sap feeding - symbiotic micro-organisms example

Answer 26

Aphids and the bacterial symbiont *Buchnera*

Question 27

solutions to sap feeding: symbiotic micro-organisms example - Aphids and *Buchnera*

Answer 27

- aphids rely on bacteria metabolism for essential amino acids - *Bunchnera* rely on aphids for place to live (aphids have special folds in gut tissue for them) - *Bunchnera* maternally transfers in eggs of aphids; co-speciation of host and symbiont

Question 28

symbiotic micro-organisms example: Aphids and *Buchnera* - Experimental evidence

Answer 28

- treat aphids with antibiotic, they will not die immediately but cannot continue growing and molting - Unless they are supplemented with amino acids