L4 Insect anatomy (thorax, legs and wings) Flashcards
What is another name for the thorax
Mesosoma
What are the 3 sections of the thorax and ehat is found on each section
Prothorax = pair of legs
Mesothorax = pair of legs and wings
Metathorax = pair of legs and wings
What are sclerites
What joins them
Set of plates
Connected by tough elastic membrane
What are the 3 types of sclerite
Nota
Pleura
Sterna
What is the shape and location of the nota, pleura and sterna sclerites
Nota - concave, upper surface
Pleura - convex, lower surface
Sterna - ventral (sides)
What specialisation is seen in the thorax of Hymenoptera
Mesosoma dividied in to 3 thoracic segments and 1st abdominal segment
What specialisation is seen in the thorax of Hymenoptera
Mesosoma dividied in to 3 thoracic segments and 1st abdominal segment
Which suborder of Hymenoptera has this specialisation
Apoctita - bees, wasps and ants
Which suborder of Hymenoptera has this specialisation
Apoctita - bees, wasps and ants
What is the 1st abdominal segment of Apocrita called
Propodeum
What is the 1st abdominal segment of Apocrita called
Propodeum
What adaptation is found in the thorax of Odonata and why
Mesothorax as greatly enlarged as it contains the flight muscles
What are pseudopods
Fake legs
A holometabolous species may … legs
Lack or have
Lack
What is the name for species where the adult and larvae will both have legs
Hemimetabolous
What does apodous mean
To lack legs
What does apodous mean
To lack legs
How many joints does an insect leg have
6
How many joints does an insect leg have
6
A two-segmented trochanta is found in which insect order
Odonata
If a 2-segmented trochanter is present, what is the appearance of the second trochanter
Appears as part of the femur
What is the tarsus subdivided into at its end
Pretarsus
Typically 2 clawed
What is the tarsus subdivided into at its end
Pretarsus
Typically 2 clawed
Where on the body do female bees collect pollen
Hind tibia
Basitarsi (top tarsal segment)
Sometimes abdomen
What adaptations do bees have for pollen collection
Enlarged tibia
Dense hairs = pollen brush
What is a corbicula
What is its structure
Pollen basket
Smooth shiny area surrounded by ring of long hair on hind tibia
Which type of bees have corbicula
Female social bumblebees
What is the general structure of wings
Membrane supported by series of sclerotinised veins
What element of wings can be seen on hemimetabolous insects
Small wing buds on exoskeleton
What element of wings can be seen on hemimetabolous insects
Small wing buds on exoskeleton
How many pairs of wings do most insects have and where are they found
2
forewings on mesothorax
hindwings on metathorax
If only one sex has wings, which is it more likely to be
Males eith wings
Give an example of an insect where only the males are winged
Moths
Give an example of an insect where only the demale is winged
Fig wasp
Which of the wings (forewing or hindwing) is more likley to be folded
Hindwing
How many main theories of wing evolution are there and what are they
- extensions of thoracic section, originally acted as parachutes
- wings derive from tracheated gills of gill covers
- from inner or outer leg segemnts closed to body
What theory of wing evolution is most supported and what is it supported by
Evolution from inner or outer leg segments close to body
Has fossil and molecular evidence
What fills the wing veins
Haemolymph
Why are wings soft when they first emerge
They aren’t filled with haemolymph
What vien is unique to hourse flies
Spirrius vein
Give 6 functions of wings
Communication
Camoflauge
Thermoregulation
Protection
Balance
Flight
What is crypsis
Camoflauge
How do wings assist in thermoregulation
Different colours reflect / absorb wavelengths of light
Changes in wing posture - open wings and face towards sun to increase warmth
Where are butterflies with more black patches on wings likely to be found
Further North, particularly Alpine species or morphs
How is the forewing of Coleoptera modified, what is this called
Hardened into elytra
What is the name for the hardened forewing of Hemiptera
Hemelytra
What is the role of the elytra / hemelytra
Protect hindwings for flying
What is the name and structure of the modified forewing in Orthoptera, Dermaptera, Mantodea, Phasmatodea and Blattodea
Leathery structure
Tegmina
How can tegmina help in camoflauge protection
Tagmina are drab but cover the aposematic display
How can tegmina help in camoflauge protection
Tagmina are drab but cover the aposematic display
What are the hind wings of Diptera modified
Halters
What is the role od halteres
Stability in flight
What percentage of animals are invertebrates
97%
When did flight evolve
300 million years ago
What are the 2 methods of wing muscle attachment
Direct or indirect
What is the structure of direct flight muscles
Wing muscles insert directly at wing base, hinged
What kind of wing attachment to Paleoptera (Odonata and Ephemeroptera) have
Direct
In direct muscle attachment: if the wing base moves downwards, the wing lifts…
Upwards
What 2 muscles are involved in direct muscle attachment
Elevator and depressor
What 2 muscles are involved in indirect muscle attachment
Vertical and longitudinal
What is the structure of indirect muscle attachment
Muscles attached to thorax
How do wings move in indirect muscle attachment
Flight powered by force of muscle contraction and distortion of thorax
Which insect group uses indirect muscle attachment
Neoptera
What is affected by the ratio of muscle contractions and nervous innervations
Wing beats and frequency
Which insect groups use synchronous wing contraction
Odonata
Blattodea
Orthoptera
Lepidoptera
What is the ratio of nerve impulses to wing beats in synchronous contraction
1 nerve impulse equates to 1 wing beat
What wing frequencies are associated with synchronous contraction
Up to 100Hz
What wing frequencies are associated with asynchronous contraction
> 500 Hz
What insect groups use asynchronoys contraction
Hymenoptera
Coleoptera
Diptera
Hemiptera
Is direct or indirect muscle attachment capable of higher wing beat frequency
Indirect capable of higher wing beat frequency
