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72% Water + 28% land

Entomologists???

Insects in Aquatic Ecosystem

K .Elango

what is Aquatic insects ???

Why do we care ???

Habitat of Aquatic insects ???

Adoptions of aquatic insects ???

Uses of aquatic insects???

Just listen this seminar…

• 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 three categories:

1. Plankton - Drifters 2. Nekton - Free-swimmers 3. Benthos - bottom dwellers

Aquatic Ecosystem

(Danks , 2002)

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.

(Subhashini et al ., 2008)

Aquatic insects

Why do we care ???

Major component of the aquatic food chain

Indicators of aquatic health

Affect human health

Role in forensic investigation

Business partner

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

* ---- Minor aquatic order with only a few aquatic species ** ---- Entirely aquatic orders

122912 orders ,150 Families ,8600

Species

1 mm

21 cm

Small & Larger Aquatic insectsMegaloptera

Hymenoptera

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 ( Not feed) • Upto 45 instars

Nymph Adult

All odonates are predators as both nymphs and adults

• Eggs –nymph–adult• Up to 20 instars

• Predacious • No external gills • Longer body on damselflies (wings up) • Dragonflies (wings down)

Odonata – Dragon fly, Damsel fly 9 families with 407 species

Nymph Adult AdultNymph

Damsel fly Dragon fly

Plecoptera – Stone flies 9 families and 626 species

• Mostly temperate regions• Closed tracheal system with anal gills• Need high oxygen, good environmental

indicators.• Upto 10-33 instars• Water purity indicator

Nymph Adult

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.

Aquatic bugs

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 • Larva –undeveloped eyes, sometimes have tusks

Aquatic beetles

Coleoptera

( Subramanian and Sivaramakrishnan, 2007 )

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

Diptera

( Subramanian and Sivaramakrishnan, 2007 )

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

larva Adult

Trichoptera

( Subramanian and Sivaramakrishnan, 2007 )

( Subramanian and Sivaramakrishnan, 2007 )

Submerged plants

Habitat of Aquatic insects

Sediment (mud)

Freely in the water Around rocks

Habitat of Aquatic insectsCollembola 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 ( Ronald et al., 2007 )

Structure and Appearance

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 )

Lifecycle and Development

( Hope Batcheller, 2010)

Food sources & Feeding mechanism

1. Scrapers

2. Collectors

3. Shredders

4. Predators

Food sources - Functional feeding groups

Categorize :

(Reese , 2009)

Scrapers : - special mouthparts that remove algae growing on the surface of rocks or other solid objects

Collectors : - acquire small pieces of decaying plant material (detritus)Shredders :

- aquatic insects feed on parts of live plants that grow under the water.

Feeding mechanism

Predators : - feed on other animals that are alive (small vertebrates, such as fish and tadpoles)

(Reese , 2009)

Collectors

Scrapers

Shredders Predators

1. The most common way for aquatic insects to breathe effectively underwater is to use oxygen that is dissolved in the water

2. Immature stages – Gills –obtaining dissolved oxygen - water

3. Use the holes in their bodies to get oxygen from the air – Respiratory siphon

4. A few kinds of aquatic insects have their spiracles on the end of a long tube at the end of their abdomen ( water beetle)

Respiration

( Reese Voshell , 2009)

2. Snorkel with a breathing tube : - Mosquito larva and water scorpions

3. Scuba tank :- Water beetle and Water Spider

1. Gills : - May fly , Dragon fly , Stone fly , caddish fly

Respiratory adoptions

Air = 21% O2 , 78% N2

Water = 35% O2 , 64% N2,

AirO2

O2N2

Air

Water

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 deposity 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

( Hodkinson and Jackson , 2005 )

ReproductionEphemeroptera Odonota Diptera

Coleoptera Trichoptera Plecoptera

Other aquatic adoptions1. Ripple effect:

- Most aquatic insects are sensitive to water ripples to detect predators or prey - own ripples on the water surface and process the returning "echoes" to detect prey

(Hershey et al ., 2008)

2. Double vision

- The Whirligig Beetle has eyes divided horizontally to see both under and above water. upper

lower (Hershey et al ., 2008)

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)

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 )

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

1 meter / second

( Choudhary and Ahi , 2015)

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( Choudhary and Ahi , 2015)

• No water loss from evaporation • Less temperature fluctuation • Less light for predators to see them with • Avoid competition with terrestrial species

Advantages:

• Water uptake from Osmosis • Less oxygen available • Moving water • Different food sources • Pollution

Disadvantages:

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 (ETP Group)

• Making survey of aquatic insects is called “ Bio monitoring”

(Kaur et al ., 2010)

Role in Food chains

( Baxter et al., 2005 )

Algae  →  Protozoa   →  Small Insects   →   Large aquatic Insects   →   Small fish  →  Large fish

Diseases transmitted by mosquitoes include: - Malaria, dengue, filariasis, chikungunya, yellow fever, Japanese encephalitis, Saint Louis encephalitis, Western equine encephalitis, Eastern equine encephalitis.

- Nearly 700 million people get a mosquito borne illness each year resulting in greater than one million deaths

Mosquito Vs Human

(Bond et al., 2014)

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

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

Role in forensic investigations - Seven orders are used in forensic studies - Ephemeroptera,Odonota,Plecoptera,Hemiptera,Trichoptera,Coleoptera,Diptera

(Merritt and Wallace , 2010)

(Merritt and Wallace , 2010)

ETP Group

HemipteraColeoptera

Odonata Diptera

(2-13 days)

(14-38 days)

(39-161 days)

(161-225 days)

(225-338 days)

• 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

(Duprat , 2007)

Case study

Case study - 1

- Relationship between some aquatic insect species (Ephemeroptera, Plecoptera,Trichoptera and Odonata) and some heavy metals (cadmium, lead, copper, zinc, nickel, iron and manganese) and boron were assessed using data obtained from the Ankara Stream .

Study area

(Girgin et al., 2010)

- Mycobacterium ulcerans is an emerging environmental pathogen which causes chronic skin ulcers. - Report that M. ulcerans may be transmitted to laboratory mice by the bite of aquatic bug (Naucoridae) that are infected with this organism

( Marsollier et al., 2002)

Case study - 2

Water pollution

Danger !!!

Avoid Water pollution ….save us…

THANK YOU……..

By K.ELANGO