ENTM 340 Insect Pests of Trees Turf and Ornamentals�

C. Sadof� Purdue University

Laboratory 2�� Gross Insect Anatomy

 

Part 1:� The Grasshopper

Collect� 1 grasshopper and a tray from the main bucket to your desk.� Use one insect to examine, the other to dissect.

External Anatomy:

  1. The insect head.�
    1. Draw the grasshopper head.� Label the following parts:� Compound eyes, ocelli, labrum, maxillary palp, vertex, ecdysial suture. Antenna (scape, pedicel, flagellum)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

What is the function of the ecdysial suture line in the process of ecdysis?

 

 

 

    1. Extract the following mouthparts and draw.

 

Labrum, mandible, maxilla, labium, hypopharynx.

 

 

 

 

 

 

 

 

 


  1. The thorax.
    1. � Remove the� fore and hind-wings� from one side� of the grasshopper and draw each.� Note how the hindwing is folded beneath the forewing.

 

 

 

 

 

 

 

 

 

 

 

 

    1. Remove the legs of one side of the grasshopper. Draw the fore, mid and hind legs and label the Coxa, trochanter, femur, tibia, tarsus and pretarsus,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

c.� Grab the hind leg and move it around to determine its range of movement at the body wall. �Note how this single articulation (monochondyllic) allows a circular movement.� Contrast this with the range of movement of the doubly articulated (dichondyllic) joint between the tibia and the femur.


    1. Draw the metathoracic segment.� Find and label the notum, pleuron, pleural suture, sternum and the spiracle.

 

 

 

 

  1. Abdomen.�
    1. Draw and abdominal segment and label, the notum, pleruon, sternum and spiracle.

 

 

 

 

 

 

 

 

 

����������� b.� Draw the cerci as attached to the last abdominal segment.

 

 

 

Internal Anatomy

 

Dissect the grasshopper and draw the relative position of the dorsal vessel, the alimentary canal and the ventral nerve cord.

 

 

 

 

 

 

 

Dissect an abdominal segment and examine the location of the tracheae in relation to the spiracle.

 

 

 

 

 

 

 

 

 

 

 

Part 2.�� Insect Adaptations

 

Examine the specimens in the Adaptations box and draw adaptations of

 

Digging legs

 

 

 

Jumping legs

 

 

 

Swimming legs

 

 

 

 

 

 

Sucking mouthparts.

 

 

 

 

 

 

Part 3.�� Live specimens.��

 

a. Observe an aphid feeding and record what you see.

 

 

 

 

 

 

 

b. Observe caterpillar feeding and record what you see.��