 Diagram on page 54
Terminology
 Glossary on pages 179-185
Ward et al.’s key to orders
Ephemeroptera
 Mayflies
 All larvae aquatic
 Characteristics
 Wing pads
 1 claw on each leg (contrast
with Plecoptera)
 2-3 terminal segmented
filaments (cerci) on
abdomen
 Usually with lateral
abdominal gills
Plecoptera
 Stoneflies
 All larvae aquatic
 Characteristics
 Wing pads
 2 claws on each leg (contrast
with Ephemeroptera)
 2 cerci
 No lateral abdominal gills
Trichoptera
 Caddisflies
 All larvae aquatic
 Characteristics
 No wing pads (contrast with
Ephemeroptera and
Plecoptera)
 3 pairs of jointed legs on
thorax (contrast with Diptera)
 1 pair of terminal abdominal
prolegs (contrast with
Lepidoptera and larval
Coleoptera)
 Often in cases
Diptera
 True flies
 All larvae aquatic
 Characteristics
 No jointed legs on thorax,
some with prolegs on
prothorax (contrast with
Trichoptera, larval
Coleoptera and
Lepidoptera)
 Very diverse group
What are these taxa?
 Chironomidae
Coleoptera
 Beetles
 Some adults and larvae aquatic
 Mostly lentic except for
Elmidae
 Characteristics
 Adults


1st pair of wings hardened to
form nonoverlapping shell-like
covering (elytra) over abdomen
(contrast with adult Hemiptera)
Chewing mouthparts
Coleoptera
 Characteristics
 Larvae


3 pairs of jointed legs on
thorax (contrast with Diptera)
No terminal abdominal
prolegs (contrast with
Trichoptera)
Odonata
 Dragonflies and damselflies
 All larvae aquatic
 Mostly lentic
 Characteristics
 Wing pads
 No cerci, some with
unsegmented terminal gills
(contrast with Ephemeroptera
and Plecoptera)
 Grasping mouthparts forming
hinged structure (labium)
under head (contrast with
larval Hemiptera)
Hemiptera
 True bugs
 Some adults and larvae aquatic or
semi-aquatic
 Mostly lentic except for
Naucoridae
 Characteristics
 1st pair of wings with hardened
base and overlapping
membranous apical portion
(contrast with adult Coleoptera)
 Sucking/piercing mouthparts
forming long jointed beak
(contrast with larval Coleoptera
and Odonata)
Lepidoptera
 Butterflies and moths
 Few larvae aquatic
 Mostly lentic except for
Pyralidae
 Characteristics
 3 pairs of jointed legs on
thorax (contrast with Diptera)
 At least 2 pairs of abdominal
prolegs terminating in circle of
hooklets (crochets) (contrast
with Trichoptera and larval
Coleoptera)
Megaloptera
 Dobsonflies and alderflies
 All larvae aquatic
 Mostly lentic
 Characteristics
 7-8 pairs of lateral abdominal
filaments (contrast with
Trichoptera and larval
Coleoptera)
 Sialidae with long pointed
filament at apex of abdomen
 Corydalidae with anal hooks
on final abdominal segment