Transcript CEW BMI Identification Guide

Citizens’ Environment Watch
Water Quality Monitoring
with Benthic Macroinvertebrates
Benthic Macroinvertebrate Identification Guide
1
Coelenterata (Hydras)
• Size range: 2-25 mm
long
• Movement: sessile
• Colour: variable, often
clear to whitish
• Inconspicuous, tube with
tentacles
• Asexual reproduction
through budding
2
Turbellaria (Flatworm)
• Size range: 5-30 mm
• Movement: creep slowly on
bottom
• Colour: greyish brown,
often ‘colourless’
• very flat
• unsegmented
• eyespots on head
http://www.microscopyu.com/moviegallery/pondscum/platyhelminthes/dalyellia/
3
Nematoda (Roundworms)
• Size range: usually <1
cm long
• Movement: Rapid, whiplike movements
• Colour: usually
transparent
• Unsegmented
• Usually tapered at both
ends
4
Oligochaeta
(Aquatic Earthworm)
• Size range: 1-30 mm
• Movement: crawl along
bottom of tray
• Colour: pinkish, light brown
• Similar appearance to earth
worm, with bundles of hairs on
each segment behind the first
• Segmented body with clitellum
(swollen, glandular region)
5
Hirudinea (Leech)
• Size range: 5-400 mm
• Movement: inch along
bottom with the aid of
suckers at either end
of body
• Colour: brown, black,
green on top/orange
on bottom
• Segmented body
• Often with several
pairs of eyes on head
6
Isopoda (Sow Bug)
• Size range: 5-20 mm
• Movement: crawl slowly
on bottom
• Colour: brownish, red
• Many pairs of legs (up
to 8)
• Dorso-ventrally
compressed
• Often associated with
organic matter
7
Pelecypoda (Clam)
• Size range: 2-250 mm
• Movement: none (found at
bottom of tray)
• Colour: white, yellow, brown,
grey, black
• Hard shell
• Flat, 2 halves hinged
• Do not count empty shells
8
Amphipoda (Scud)
• Size range: 5-20 mm
• Movement: swim on
side
• Colour: blueish grey,
brown, green, red
• Many pairs of legs (up
to 14)
• Long antennae
http://mywebpages.comcast.net/kils/hyperia/hyperia1.htm
9
Decapodae (Crayfish)
• Size range: 10-150
mm
• Movement: walk on
bottom
• Colour: green, brown,
blue
• Similar appearance to
lobster
• Large claws
• Eyes on small stalks
• Escapes backwards by
beating tail
10
Hydrachnida (Water Mite)
• Size range: 0.4-3 mm
• Movement: appear like a
small moving dot uncoordinated,
scrambling
• Colour: bright red, green,
blue or brown
• Round body
• 4 pairs of legs
http://micro.magnet.fsu.edu/moviegallery/pondscum/arachnids/hydracarina/
11
Ephemeroptera (Mayfly)
• Size range: 3-28 mm (not
including tail)
• Movement: Swim up and
down in ‘s’ pattern
• Colour: brown or brownish
black (sometimes mottled)
• 3 pairs of legs
• Single tarsal claw
• Feather-like gills under
abdomen
• 3 tail filaments (sometimes
only 2 filaments are
present)
12
Anisoptera (Dragonfly)
• Size range: 15-45 mm
• Movement: slow
• Colour: green to greenish
brown
• Larger than mayfly but
without tail filaments; no
visible external gills
• Modified labium for catching
prey
• Large eyes and head
• Often flat
13
Zygoptera (Damselfly)
• Size range: 10-26 mm
• Movement: slow moving but more active than
dragonflies
• Colour: green to greenish brown
• 3 gills present on end of tail
• Thinner than dragonfly
• Three pairs of legs
14
Plecoptera (Stonefly)
• Size range: 5-50mm
• Movement: slow
• Colour: yellowish,
brown or blackish
(sometimes mottled)
• Similar to mayfly but
with 2 tail filaments
• Sometimes featherlike gills under body
(not dorso-lateral on
abdomen)
• Tarsi with 2 claws
15
Hemiptera (True Bug)
• Size range: 15-40 mm
• Movement: swimming or
skimming on water surface
• Colour: black or brownish
• Legs sometimes long and
stick out from body
• Often 2 pairs of soft folded
wings
• Often with well developed
breathing appendages
• Sucking mouth parts
(rostrum)
16
Megaloptera (Helgrammite)
• Size range: 25-90 mm
• Movement: Crawl on
bottom
• Colour: brown
• Large, similar in
appearance to centipedes
(the ‘hairs’ are actually gill
filaments)
• 3 pairs of legs in anterior
abdominal segments
• Well developed mandibles
• Often with anal prolegs
17
Trichoptera (Caddisfly)
• Size range: 2-50 mm
• Movement: Slow movements
on bottom
• Colour: abdomen cream
coloured
• Often no movement if found
in cases of sticks, stone or
sand (look for heads inside
cases)
• Three pairs of legs behind
head
• Dorsal thoracic plates
variously sclerotized
• Anal prolegs with hooks
18
Lepidoptera (Aquatic Moths)
• Size range: 10-25 mm
• Movement: crawls like a
caterpillar
• Head with ring of ocelli
(small simple eye)
• 3 pairs of short,
segmented, thoracic legs
(between head and
abdomen)
• Ventral, abdominal
prolegs
19
http://www.nature.ca/rideau/b/b5b-e.html#synclita
Coleoptera (Beetle)
• Size range: 2-40 mm
• Movement: swimming or crawling
on bottom
• Colour: brown, black, mottled
• Most have 3 pairs of legs near
head
• Larvae are similar to caddisfly
larvae but bodies are hard, with
mandibles, maxillae, labium and
2- or 3-segmented antennae;
may have unsegmented terminal
abdominal appendages
• Adults: hardened forewings
protect soft hind wings, antennae
with 11 or fewer segments
20
Gastropoda (Snail)
• Size range: 2-70 mm
• Movement: none (found
floating or at bottom of
tray)
• Colour: grey, brown or
black
• Hard shell
• Spiral shaped
• Do not count empty
shells
21
Chironomidae (Midge)
• Size range: 2-20 mm
• Movement: whip back
and forth
• Colour: red, white or
cream
• Segmented body
• Shaped like letter “J”
when preserved
• May be in tube of silt
• Well developed, hardened
head with eyes; anterior
and posterior parapods
(lobed shaped body
extensions)
22
Tabanidae (Horsefly)
•
•
•
•
•
•
•
23
Size range: 1.5-40 mm
Movement: unknown
Colour: white or cream
pointed at both ends, leathery texture
Segmented, straight or slightly curved
7 pairs of bumps on abdomen (creeping welts with hooks)
Head retracted into thorax
Culicidae (Mosquitos)
• Size range: 3-15
mm
• Movement: twitches
when touched
• Colour: brown
• Thickened body at
head
• Segmented body,
curved at one end
http://insects.tamu.edu/images/insects/common/images/b-txt/bimg221.html
24
Ceratopogonidae
(no-see-ums)
• Size range: 3-13mm
• Movement: whipping
motion, but stiff when
picked up
• Very slender, pointed at
both ends, segmented;
small pointed sclerotized
(hard) head
• No abdominal
appendages; may have
some terminal abdominal
hairs
25
http://www.junglewalk.com/popup.asp?type=v&AnimalvideoID=3160
Tipulidae (Cranefly)
• Size range: 10-45
mm
• Movement: similar to
a worm
• Colour: white,
yellowish or light
brown
• One end with finger
like projection, lobes
or long hairs
• Reduced head is
retracted into thorax
• Soft body; may have
creeping welts
26
http://www.ent.iastate.edu/imagegal/diptera/tipulidae/3936.94craneflylarv.html
Simuliidae (Blackfly)
• Size range: 3-15 mm
• Movement: Similar to
an inch worm
• Colour: brown or
greyish
• Often with labral fans
• Similar to flattened
maggot with one end
1/3 fatter
• Sessile (non-motile),
attached at posterior
end
27
Misc. Diptera
(Misc. True Flies)
• Size range varies
• May have parapods,
pseudopodia (temporary
projection), creeping
welts or other
appendages, but no
jointed thoracic legs
• Often maggot-like; head
may be retracted into
thorax
• Adults with one pair of
wings
28
References
• Images and characteristics adapted from Gartner Lee
Limited, 1997 and Ontario Benthos Biomonitoring
Network, 2005
• Commonness rankings from Jacques Whitford
Environmental Limited, 2001
• Tolerance values taken from Watershed Report Card,
2000
29
Thank You!
For more information, please contact:
Citizens’ Environment Watch
401 Richmond St. W. Suite 380
Toronto ON M5V 3A8
P: (647) 258-3280
F: (416) 979-3155
www.citizensenvironmentwatch.org
[email protected]
30