aquatic insects, orders, systems, uses and case study

1. Insects in Aquatic Ecosystem
Suprabha
PALB 4109

2.  What is an Aquatic insects ???
 Importance
 Habitat of Aquatic insects ???
 Adoptions of aquatic insects ???
 Uses of aquatic insects???

3.  One million known insect species, there are over 8000
species that fall into the macro invertebrate category
 All living organisms in aquatic environments fall into one
of the four categories:
1. Plankton - Drifters
2. Nekton - Free-swimmers
3. Benthos - bottom dwellers
4. Pleuston - air water interferace
Aquatic Ecosystem

4.  Truly aquatic insects are those that spend some part of
their life-cycle closely associated with water, either living
beneath the surface or skimming along on top of the water
 The immature stages are truly aquatic while the adult is a
winged terrestrial form.
Aquatic insects

5. Aquatic Insect Orders
1. Collembola*
2. Ephemeroptera **
3. Odonota**
4. Plecoptera**
5. Hemiptera
6. Megaloptera
7. Neuroptera*
8. Trichoptera**
9. Lepidoptera*
10. Coleoptera
11. Hymenoptera*
12. Diptera
12 orders ,150 Families ,8600 Species

6. Small and Larger Aquatic insects
Megaloptera
Hymenoptera

7. Ephemeroptera
May fly - 21 families with 676 species
 Eggs –Nymph– Adult
 Naiads often with abdominal gills
 Maxillary and labial gills
 3 styli on naiads and adults
 Nymph (Predacious)
Adult ( do not feed)
 Upto 45 instars

8.  Eggs –nymph–adult
 Up to 20 instars
 Predacious
 Gills present
 Mask present
Odonata
Dragon fly, Damsel fly- 9 families with 407 species
Damsel fly
Dragon fly

9. Plecoptera
Stone flies- 9 families and 626 species
 Mostly temperate regions
 Anal gills
 10-33 instars
 Need high oxygen, good
environmental indicators.
 Water purity indicator

10. Hemiptera
Back swimmers, Water Boatmen, water bugs , water strider,
water scorpions
 Diving or at surface
 Adults and naiads both aquatic.
 Highly modified legs.
 Generally wings still functional as
adults, can disperse between
waterways.

11. Coleoptera
Diving beetles, Whirligig beetles, Scavenger beetles
Egg – larva –pupa – adult
 Larva very different from adult
 Adults – have hard case on body that does not
overlap
 Adults have chewing mouthparts
 Predatious

12. Coleoptera

13. Diptera
Mosquito , Meniscus midges, Chironomids
29 families and 3,500 species
 Larvae are maggot like or worm like
 Very diverse in aquatic ecosystem
 Anal spiracles breathing at surface
 upto 5 instars

15. Trichoptera
Caddisflies - 21 families and 1,400 species
 Caddisflies are related to
Lepidoptera and resemble small hairy
moths
 Wings are covered in dense hairs
rather than scales
 Upto 6-7 instars
 The larvae may be either
herbivorous or predatory

17. Megaloptera
Dobsonflies and Alderflies
 Gills present
 Complete metamorphosis
 Larvae of some of the larger kinds are called hellgrammites,
which are popular as live bait for smallmouth bass and other
warm-water fish species.
Dobsonfly Alderfly

19. Habitat of Aquatic insects
Collembola Ephemeroptera Odonota Plecoptera
Hemiptera Trichoptera Coleoptera Diptera
Springs and spring ponds Lakes and Streams Lakes and Streams Streams
Lake and Stream
Margins
Lakes and Streams Lakes and Streams All Aquatic Habitats

20. Structure and Appearance

21. Lifecycle and Development
1. Slow season life cycle
- Mayflies, Stoneflies, And Caddisflies
2. Fast season life cycle
- caddisflies and dragonflies
3. non seasonal life cycle
- Hellgrammites
Life cycles for aquatic insects may be very short or very long
( Voshell et al ., 2002 )

22. Lifecycle and Development

23. Food sources & Feeding mechanism
1. Scrapers
2. Collectors
3. Shredders
4. Predators
Functional feeding groups
Categorize:

24. Scrapers
Collectors
Feeding mechanism

25. Shredders
Predators
Feeding mechanism

26.  Use oxygen that is dissolved in the water
 Immature stages – Gills –obtaining dissolved oxygen -
water
 Use the holes in their bodies to get oxygen from the air –
Respiratory siphon
 Spiracles on the end of a long tube at the end of their
abdomen ( water beetle)
Respiration

27. 2. Snorkel with a breathing tube :
3. Scuba tank :
1. Gills
Respiratory adoptions

28. Reproduction
 Only adult insects are capable of reproducing, and most
aquatic insects spend their adult stage out of the water
 After mating on land, females return to the water to
deposit her eggs
 Eggs are usually stuck on solid objects under water, but
a few kinds deposit the eggs on trees or rocks above the
water

29. Reproduction
Ephemeroptera Odonota Diptera
Coleoptera Trichoptera Plecoptera

30. Other aquatic adoptions
1. Ripple effect:
signals are usually produced by
vertical oscillations of the legs
which remain in contact with the
water.
Ripple signals occur in the contexts
of calling and courtship
(precopulation), copulation,
postcopulation, sex discrimination,
induction of oviposition, individual
spacing, territoriality, and food
defence
Water striders, Giant water bugs
and Whirligig beetles

31. 2. Double vision
 The Whirligig Beetle has eyes divided vertically to see
both under and above water.
upper
lower(Hershey et al ., 2008)

32. 3. Oars
 Many aquatic insects paddle underwater with oar-like legs
 Legs are long, flattened and fringed
 water beetle and water boatman
(Hershey et al ., 2008)

33. 4. Skates
 Aquatic insects skate on the water surface by distributing
their body weight over long, thin, waterproof legs.
 They paddle with the middle pair of legs, steer with the hind
legs and use the short front legs to attack and hold prey
(Englund , 2007 )

34. 5. Jet skis
 The Camphor Beetle also skates on the water surface.
 When alarmed, it releases a chemical from its back legs
that reduces the water surface tension
( Choudhary and Ahi , 2015)
1 meter / second

35. 5. Suckers
 Blephariceridae, commonly known as net-winged midges
 Found near fast-flowing streams where the larvae live
 Suckers are sometimes called creeping welts
Immature stagesAdult

36. Importance of Aquatic Insects
 Major component of the aquatic food web
 Indicators of aquatic health
 Affect human health
 Role in forensic investigation
 Business partner

37. Aquatic insects and Water quality
 Hazardous chemicals, automotive products, pesticides,
fertilizers, pet wastes, excessive soil erosion and air pollution
all contribute to water pollution.
Mayflies Stoneflies Caddisflies
 Making survey of aquatic insects is called “ Bio monitoring”
(Kaur et al ., 2010)

38. Role in Aquatic Food web
( Baxter et al., 2005 )
Algae → Protozoa → Small Insects → Large aquatic
Insects → Small fish → Large fish

39. Ibisbill
Ibidorhyncha struthersii

40. 1. Malaria
2. Kala Azar
3. Dengue
4. Plague
5. Filariasis
6. Chickungunya
7. Lyme disease
8. Yellow fever
9. Chagas’ disease
10. Japanese encephalitis
Mosquito v/s Human
(WHO, 2015)

41. Zika virus outbreak - 2015
 The outbreak began in April 2015 in Brazil, and has spread
to other countries in South America, Central America,
Mexico, and the Caribbean
 The virus is spread mainly by the Aedes aegypti

42. Role in forensic investigations
1. Ephemeroptera
2. Odonota
3. Plecoptera
4. Hemiptera
5. Trichoptera
6. Coleoptera
7. Diptera
(Merritt and Wallace , 2010)

43. (Merritt and Wallace , 2010)
ETP Group
Hemiptera
Coleoptera
Odonata
Diptera
(2-13 days)
(14-38 days)
(39-161 days)
(161-225 days)
(225-338 days)

44.  In 2007 profile of Hubert Duprat's work with caddis fly larvae is
a tiny, entomological miracle.
 The larvae build their cocoons with whatever material is at
hand
 Duprat forces them to build with gold and precious gems,
making spectacular bio-organic jewelry
Business partner

48. Water
pollution
Danger !!!

49. Giant Water Bug
Lethocerus indicus

50. Researchable Area
 Aquatic insects of Village Irrigation Tanks
 Community structure of aquatic in a Village
Irrigation Tank
 Changes in the diversity and Community
Structure of aquatic insects due to Sewage
Pollution in Bangalore Lakes
 Can aquatic insects be a good indicators of
pollution levels in Bangalore Lakes

51. Avoid Water pollution ….save us…

52. THANK YOU……