Download Aquatic Insects

Water bug Video:
https://www.youtube.com/watch?v=67ZiyiyJv_Y
Source: http://www.austincc.edu/sziser/txaqinverts/AITdistribrecords.html
Source: http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/insects.html
Source: https://thedragonflywoman.com/
Source: http://www.ento.csiro.au/education/insects/odonata.html
“BUGS”
 Bugs include many invertebrates, but typically with
segmented bodies, hard outer skeleton, and jointed
legs
 Bugs are Arthropods and include insects, spiders,
mites, scorpions, millipedes, centipedes, and
crustaceans
 Invertebrate animals that are soft-bodied and without
legs are not usually considered to be bugs. Worms
belong to the phylum Annelida and slugs and snails
belong to the phylum Mollusca.
General Arthropod Characteristics
 Skeleton
 Called the exoskeleton since it provides structure
 It is made of chitin
 Covered in a thin layer of wax to prevent its body from
losing water
 Body Parts
 Insects (Arthropods) have three main body parts
 Spiders (Arachnids) have two main body parts
 Centipedes and Millipedes (Myriapods) have many
small body divisions
Insect Characteristics
 All adult insects have six legs and pair of antennae
or feelers
 Body parts include:
 Head – Eyes, Mouthparts, and Antennae
 Thorax – legs and wings if any
 Abdomen – digestive and reproductive organs
Insect Life Stages
 Complete Metamorphosis
 Insects have four life stages:
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Egg
Larvae
Pupa
Adult
 Larvae look dramatically different than the adult insect and must go
through pupal stage before it develops into an adult
 Once metamorphosis is complete, it has wings, fully functional
reproductive parts, and looks just like its parents
 This process gives the insects a significant advantage
 Since the larvae and adult are so different, they do not complete for the same food
source
 Complete metamorphosis occurs in 85% of known insect species
 major insect groups such as beetles, wasps, bees, ants, flies, moths, and butterflies
 other insect species such as fleas, alderflies, lacewings, scorpion flies, and caddisflies
Dragonfly Metamorphosis Video:
https://kera.pbslearningmedia.org/resource/tdc02.sci.life.cyc.metamorph/metamorphosi
s-change-of-plans/#.WM6_LDsrLIU (1:52-3:04)
Insect Life Stages
 Incomplete Metamorphosis
 Insects have three life stages:
 Egg, nymph (larvae), and adult
 Insect begin life as a wingless nymph that typically looks like a
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miniature adult
With each successive moult, the insect increases in size and
looks more and more like the adult
For flying insects, the wings eventually appear after moulting
The final moult will produce full wings and be able to reproduce
The remaining 15% of insects which undergo incomplete
metamorphosis include:
 Silverfish, mayflies, dragonflies, damselflies, stoneflies, and true bugs
Terrestrial versus Aquatic Insects:
Aquatic Insect Adaptations
 Insects first evolved on land about 350 million years ago.
Before they could completely adapt to aquatic
environments, they had to develop different ways of
respiration.
 Methods:
 Use of an air bubble (like a human oxygen tank)
 Utilize oxygen in water via plastron or gills
 Most gills membranes are only one cell thick
 Allows gas exchange between water that flows over them
 Capillaries connect cells in the gills so gasses can be taken in from
water and passed into bloodstream of aquatic animal
 Gaseous waste also passes out from gills into water environment
Terrestrial versus Aquatic Insects:
Aquatic Insect Adaptations
 Store oxygen in hemoglobin
molecules or hemolymph
 Hemoglobin absorbs more
oxygen so the few insects with
this ability are typically found in
low oxygen environments since
they are one of the few that can
survive in those environments
 Some insects in the Diptera
Order, such as the non-biting
midgefly, are able to obtain
oxygen through their
hemoglobin-like proteins to
Image: Chironomids (Bloodworms)
“breathe” in low oxygen
environments
Terrestrial versus Aquatic Insects:
Aquatic Insect Adaptations
 Breathing tubes to get oxygen from above water surface (like a
snorkel)
 Internal network of tubes is called a trachea
 Holes that open to outside surface are called spiracles
 Oxygen diffuses directly into the trachea and oxygen exits through the
spiracles
 Oxygen and CO2 do not need to be carried through a circulatory system
since tracheal system pervades all parts of the insects body
 Obtaining oxygen through an integument (cutaneous “skin” or
plastron respiration)
 Very few small animals and a few larger animals that live in moist
environments use this kind of respiration
 Typically able due to capillaries underneath skin that allows exchange of
oxygen and carbon dioxide
 Example: some species in the orders Hemiptera and Coleoptera
and most worms
Classification
 King Phillip Came Over For Girl Scouts
Classification
 Kingdom Phylum Class Order Family Genus species
Insect Classification
 Domain: Eukarya
 Kingdom: Animalia
 Phylum: Arthropoda
 Class: Insecta
 Order…
Greek
 “ptera” means wing
 “odonto” means tooth (referring to prominent
mandibles in Odonata)
 “coll” means glue and “embol” means a wedge
(referring to wedge-shaped structure underneath first
abdominal segment in Collembola)
Aquatic Orders found in Texas
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Plecoptera – 3,497 species in world, 45 in Texas
Ephemeroptera – 3,046 species in world, 165 in Texas
Odonata – 5,680 species in world, 261 in Texas
Collembola – 414 species in world, 21 in Texas
Megaloptera – 328 species in world, 6 in Texas
Neuroptera – 73 species in world, 3 in Texas
Lepidoptera – 739 species in world, 16 in Texas
Hymenoptera – 150 species in world, 5 in Texas
Hemiptera – 4,656 species in world, 192 in Texas
Coleoptera – 12,604 species in world, 339 in Texas
Trichoptera – 12,627 in world, 240 in Texas
Diptera – 37,226 species in world, 817 in Texas
Order: Collembola (springtails)
 2 main body shapes: elongate and cylindrical OR more
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compact and spherical
Simple eyes
Forked tail-like structure on underside of abdomen
Antennae in 4-6 segments
Mouthparts hidden
Image: Springtail
Order: Odonata (dragonflies and
damselflies)
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Long slender abdomen
Image: Dragonfly nymph
Large compound eyes
3 ocelli
Very small antennae
Image: Damselfly nymph
Mandible mouthparts
Two pair of membranous wings of similar shape and size
Have gills
Complex wings venation with many cells
Damselflies hold wings vertically when at rest while
dragonflies hold wings horizontally while at rest
Dragonflies Video:
https://kera.pbslearningmedia.org/resource/ket08.sci.life.oate.dragonflies/dragon
flies-in-kentucky/#.WM6-9TsrLIU
Order: Ephemeroptera (mayflies)
 Average wingspan of 15mm
 Only insect with both middle and tail filament
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and wings
Have gills
Nymphs feed on floating organic matter or algae
Adults do not eat and are very short-lived
Predators include other insects, spiders, fish,
crustaceans, birds, and frogs
Image: Mayfly nymph
Image: Mayfly adult
Order: Plecoptera (stoneflies)
 Elongated body less than 50mmin length
 Two pairs of wings
 Long cerci but lack middle tail filament
 Nymphs feed on algae and plant debris, or other aquatic
insects
 Adults feed on lichen, algae, and rotten wood
 Predators include other insects, spiders, frogs, reptiles,
birds, and bats
Image: Stonefly nymph
Order: Megaloptera (alderflies, fishflies,
dobsonflies, hellgrammites (dobsonfly larvae))
 2 pairs of large wings
 Wingspan can vary from 20-100mm and have many
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cross veins
Adults are similar to lacewings but veins do not branch
at edges
Larvae live between 1 to 5 years
Larvae eat other insects
Adults rarely eat and are short lived
Image: Dobsonfly
Have gills
 Predators include spiders, frogs, and tortoises
Order: Megaloptera (alderflies, fishflies,
dobsonflies, hellgrammites (dobsonfly larvae))
Image: Hellgramite (larvae of dobsonfly)
Image: Hellgramite
Order: Neuroptera (lacewings, mantidflies,
antlions, spongeflies/spongilla flies)
 Wingspan ranges from 5 to 150mm
 Body up to 50mm
 Wings appear lace-like
 2 pair of wings of relatively equal length
 Relatively large compound eyes
Image: Spongillaflies
 Differ from dobsonflies and alderflies by having forked
veins
 Differ from stoneflies and dragonflies by lacking two thin
abdominal cerci (jointed appendages on tip of abdomen)
 About 6,000 species
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
 50,000 to 80,000 species
 Characterized by sucking mouthparts
 Vary from 1-110 mm
 Have well-developed compound eyes
 2-3 simple eyes and antennae
 Most have two pair of wings but some are wingless
 Feed on plant juices or other insects
 Predators include other insects, spiders, frogs,
reptiles, and birds
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Giant Water bug, Lethocerus medius
(note respiratory tube)
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Toad Bug
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Gelastocoridae a.k.a. Toad Bug
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Creeping Water Bug
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Marsh Treader
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Water Scorpion
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Water bugs hatching
Order: Hemiptera/Rhynchota (“true bugs” –
water striders, giant water bugs, toad bugs,
marsh treaders)
Image: Backswimmer
Order: Hymenoptera (ants and
wasps)
 Two pair of membranous wings although some are
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wingless
Forewings are larger than hindwings
Females have hardened ovipositor which may be
modified for stinging
Most have constriction in the first two segments of the
abdomen (known as a wasp-waist)
Usually large compound eyes
Larvae lack many of the external features above
 Most are grub like with no legs
Order: Diptera (flies and mosquitos)
 One pair membranous wings
 Sucking mouthparts
 Large compound eyes
 Short simple antennae
 Estimated to be 1,000,00 species
Image: Non-biting midgefly
although only about 125,000 have
been described
Order: Mecoptera (scorpionflies)
 Slender with 2 pair of wings
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although one species is
wingless
Wings have cross veins and
can span 50mm
Mouthparts are beak-like
Males have large genitalia
that resemble stinging tails of
a scorpion
Eat other insects, but some
are vegetarian
 Predators include mostly
web building spiders
Image: Scorpionfly
Order: Lepidoptera (aquatic moths)
 2 pair of membranous wings covered in scales
 A few moths are wingless
 Large compound eyes
 Antennae present
 Mouthparts formed into a sucking tube called a
haustellum
 Larvae called a caterpillar
Order: Trichoptera (caddisflies)
 Medium sized insects up to 40mm in
length
 Resemble hairy moths; however, wings
are densely covered in hairs rather than
scales
 Larvae eat a range of plants and algae,
occasionally other insects
 Predators of larvae are mainly fish
 Predators of adults include spiders,
birds, bats, reptiles, and frogs
Image: Caddisflies
Order: Trichoptera (caddisflies)
Image: Caddisfly larvae
Image: Caddisfly larvae in casing
Order: Coleoptera (water beetles)
 Two pair of wings
 Hardened forewings
 Membranous hind wings
 Mandible mouthparts
 Compound eyes
Image: Various larval types of Coleoptera
Image: Diving Beetle
Image: Water Beetle
Summary
 Aquatic Insects in Nature:
https://kera.pbslearningmedia.org/resource/etv08.sci.
life.eco.insects/primitive-insects-of-the-congareeswamp/#.WM7ALTsrLIU
 Aquatic Insect Video:
https://kera.pbslearningmedia.org/resource/watsol.sci
.ess.water.aquins/aquatic-insects/#.WM6-TjsrLIU
Project: “Grow” Bloodworms
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Place tub in ground near vegetation such as under a tree branch
Fill with decaying plants
Add water
Over a few days with warm temperatures, bloodworms will begin to live beneath
decaying material while mosquito larvae will float on the surface
 To collect bloodworms, remove leaves and place them onto a screen with water
below. Bloodworms will try to escape into water when leaves dry out
 These bloodworms can serve as food to fish, salamanders, shrimp, water spiders,
freshwater lobster, and some types of water beetles
 Bloodworms can be stored in refrigerator covered by a wet newspaper