4. Hemiptera

Question 1

Hemiptera

Belostomatidae

Answer 1

Structure
• Large, robust nymphs
• Prominent eyes
• Forelegs adapted to seize and hold prey

Behaviour
• Swim with forelegs stretched forward
• Cling to submerged substrate with tip of abdomen
in contact with the air

Habitat
• Bottom of shallow pools
• Backwater areas or quiet areas of streams

Question 2

Hemiptera

Corixidae

Answer 2

Structure
• Small cigar-shaped
• Middle legs long, ending with two claws for
anchoring purposes
• Hind legs long, fringed for swimming
• No extended beak, mouthparts fused with the
head

Behaviour
• Swim in a quick darting fashion, rowing with the
hind legs

Habitat
• Shallow pools
• Quiet muddy areas of streams

Question 3

Hemiptera

Gerridae

Answer 3

Structure
• Body form either stout or narrow
• Forelegs short, adapted for seizing prey
• Middle and hind legs thin and very long

Behaviour
• Skating or leaping on the surface film of ponds
and streams

Habitat
• On surface of ponds or streams
• Shaded areas

Question 4

Hemiptera

Hydrometridae

Answer 4

Structure
• Slender stick-like bodies
• Legs and antennae very thin, frail
• Beak folds away under the head

Behaviour
• Walk about on floating vegetation
• Float around on surface of pools

Habitat
• Floating vegetation
• Backwaters of streams

Question 5

Hemiptera

Nepidae

Answer 5

Structure
• Body shapes varied according to species
• Forelegs modified for seizing prey
• Long respiratory tube on tip of abdomen

Behaviour
• Swim slowly with alternating strokes of middle and
hind legs
• Sit quietly amongst vegetation with forelegs in
striking position

Habitat
• Vegetation, trash or mud
• Shallow pools or slow streams

Question 6

Hemiptera

Naucoridae

Answer 6

Structure
•	Oval, slightly flat bodies
•	Heads exceptionally broad
•	Forelegs adapted for holding prey
•	A piercing beak situated under the head

Behaviour
• Move around in a fast half creeping, swimming
fashion
• Stings viciously when handled carelessly

Habitat
• Dense vegetation
• Edges of streams

Question 7

Hemiptera

Notonectidae

Answer 7

Structure
• Unusually large eyes
• Long hind legs

Behaviour
• Swim on their backs using only the hind legs
• Rests with body at an angle with tip of abdomen in
contact with the air
• Produce a burning sting when handled carelessly

Habitat
• Pools
• Backwaters of streams

Question 8

Hemiptera

Pleidae

Answer 8

Structure
• Very small bodies
• Strongly arched backs

Behaviour
•	Cling to submerged vegetation
•	Swims with easy, fast motion
•	Entire body covered with air bubble which shows 
        as a silvery shine

Habitat
• Dense vegetation
• Shallow, clear water

Question 9

Hemiptera

Veliidae

Answer 9

Structure
•	Small, plump bodies
•	Legs adapted for running
•	Middle and hind legs attaches to body at its 
        widest part

Behaviour
• Running on surface of water
• Scatters in all directions when disturbed

Habitat
• Pools
• Some species prefer riffles in small streams