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General Entomology EEB 286
Trichoptera and Lepidoptera
Page 1
TRICHOPTERA and LEPIDOPTERA (AMPHIESMENOPTERA)
Caddisflies, Moths, Skippers and Butterflies
The superorder Amphiesmenoptera is one of the best supported sister-lineage relationships among the hexapod
orders, with almost 20 unique traits (synapomorphies) that indicate a shared ancestry between Trichoptera and
Lepidoptera.
TRICHOPTERA
NAME ORIGIN: Gk. trichos – hair; pteron – a wing.
INTRODUCTION: Caddisflies. Larvae are important members of freshwater
ecosystems (many fish eat them). Adults look similar to primitive moths. One of
the largest lineages of aquatic insects, with over 7,000 species known worldwide
and at least 1,600 species known from North America. An estimate places the
total global fauna at over 50,000 species. The larvae are longer-lived than the
adults. The adults are primarily reproductive agents.
RECOGNITION:
Larvae:
• 2-40 mm in length
• freshwater aquatics (a few terrestrial and
marine forms)
• 6-legged and lacking mid-abdominal prolegs
with crochets of caterpillars
• paired, hooked appendages at posterior end of
the body
• many construct elaborate cases which can often
be useful when identifying specimens
Adults:
• mothlike, posture distinctive
• long, simple antennae, often held forward
• wing surfaces covered with hairs (rather than flat
scales of Lepidoptera)
• chewing mouthparts, palps well developed,
mandibles reduced
HABITATS: Larvae may be found in a diverse range of aquatic environments including springs, streams,
lakes, rivers, bogs, marshes, and temporary pools. A few tolerate saline/marine environments. Cool running waters
contain most trichopteran families, with less oxygenated environments supporting fewer taxa. Most larvae are leaf
shredders dependent on leaf input from adjacent forests, others feed on a wide variety of food resources, including
algae, organic debris, sponges, amphibian eggs and other arthropods. The crepuscular adults occur near their aquatic
habitat (most fly at sunset, a few are diurnal) and are often attracted to lights. Adults feed principally on liquid food.
COLLECTING: Adults can be collected at lights and by sweeping vegetation near aquatic habitats. They should be
collected into and stored permanently in 70-80% EtOH. Dry collected and pinned adults are not uncommon in
collections and are useful because they retain their colors better than alcohol preserved specimens. However, these
are often more difficult to identify to species as a result of distortion due to drying.
Larvae should be boiled in water and then permanently stored into 70-80% EtOH. If possible, collect and
preserve the case with the larva.
General Entomology EEB 286
Trichoptera and Lepidoptera
Page 2
LEPIDOPTERA
NAME ORIGIN: Gk. lepidos – scale; pteron – a wing.
INTRODUCTION: Moths, Skippers and Butterflies. One of the
four hyperdiverse, hexapod lineages with over 150,000 species
known worldwide (in ca. 120 families). In North America there are
ca. 900 species of butterflies and 15,000 species of moths (c.f.
Hymenoptera-36,000 and Coleoptera-35,000), with an expected
total of nearly 17,000 species including those currently undescribed.
The Connecticut fauna is around 2300. It is estimated that the total
world fauna will reach 250,000 species.
The earliest fossil records of Lepidoptera date from the
Jurassic. The success of the order was strongly influenced by the
radiation of the Angiosperms during the Cretaceous.
Lepidoptera have long been among favorite groups of
collectors – there are more field guides for the identification of
butterflies than any other insect group. Not surprisingly, butterflies
have received the majority of the efforts devoted to the conservation
of invertebrates.
RECOGNITION:
Larvae:
• caterpillars (some barely distinguishable as such)
• distinct head with up to 6 stemmata
• labial spinneret (to spin silk)
• often with prolegs on mid-abdominal segments
(segs. 3-6) and on the last segment (seg. 10)
• prolegs bearing small hooks termed crochets
• larvae of leaf-mining taxa highly modified, many
lacking legs, spinnerets, etc.
Adults:
• maxilla (galeae) often modified as proboscis
• usually with 2 pairs of wings clothed in
overlapping scales that easily dislodge
• wingspans ranging from micromoths under 3
mm to saturniid moths reaching 26 cm
HABITATS: Over 90% of lepidopteran species are phytophagous as larvae, very few are predaceous, and
species of one superfamily are ectoparisites of Homoptera. Many are detritivores and fungivores. One of the few
animal groups that can digest keratin (an animal protein in horns, finger nails, hair, and clothing) are moths. Adults
feed on nectar, sap, decaying juices, urine, carrion, and dung (the latter few for sodium and other nutrients). Most
leps are nocturnal, with the butterflies and skippers being the major diurnal groups.
COLLECTING: Lep larvae must be dropped into almost boiling water for around a minute and then permanently
stored in EtOH. Only freeze-dried specimens (that are stored frozen permanently) retain their colors with high
fidelity, so another component to an ideal collection would include color photographs of living larvae.
For killing leps use well charged cyanide or ethyl acetate killing jars with some soft tissue crumpled inside.
Don’t use that same jar for other insects because they will end up being covered in scales. Large moths may be
killed swiftly by injecting alcohol into the thorax with a hypodermic needle. Adult leps are fragile and require care
in handling. Wings and antennae are easily broken off and the scales dislodge readily. If a freezer is accessible, it
may also be used to kill leps. Glassine envelopes are useful to confine and transport leps; do not use the same
envelopes for other insects (e.g. Odonates) because the envelope will be full of scales.
Host plants are good places to find lep larvae, and adults can often be taken at flowers or at blacklights. Some
species that are rarely found by any other means can be attracted to a fermenting sugar solution painted onto trees.
For a quick-and-dirty faunal survey, leps can be stored permanently in envelopes, but for taxonomic purposes
leps should be mounted on pins with their wings spread. A collection of fully spread leps takes more space and costs
more to house than any other insect group. Small moths (wingspan <10mm) should be double-mounted with
minutien pins.
General Entomology EEB 286
University of Connecticut
Fall 2006
Family: Pyralidae (pyralid moths)
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forewing usually narrow and triangular, often nearly triangular
hindwing broad with enlarged anal area
both maxillary and labial palpi usually project forward (adults often appear
snouted)
abdominal typanum facing thorax
larvae internal feeders; some stored product pests
third largest family of Lepidoptera; 1350+ spp. in NA
Family: Geometridae (loopers, inchworms, geometers)
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often slender-bodied and broad-winged, somewhat butterfly-like
forewing pattern often continued onto hindwing
abdominal tympanum that faces thorax
subcosta bent abruptly at base in HW
male antenna (bi-)pectinate or at least thickened; that of female simple
larva missing first three (rarely just two) pairs of prolegs, looping in characteristic fashion
second largest N.A. family with 1400 + spp. in NA
Family: Saturniidae (giant silk and royal moths)
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head and eyes relatively small; lacking functional
mouthparts as adult
medium to very large
wings broad; frenulum absent or minute
antennae plumose, considerably enlarged in male
68 NA spp.
Family: Noctuidae (owlet, cutworm and noctuid moths)
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often stout bodied
thoracic tympanum located beneath base of hindwing
hindwing often with contrasting pattern, unmarked in many species
subcosta + radius fused in hindwing for only a short distance beyond basal areole
antenna simple, threadlike or rarely pectinate or plumose
largest N.A. family with ca. 3000 spp.
Family: Arctiidae (tiger moths)
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like noctuids1 but often brightly colored
thoracic tympanum located beneath base
of hindwing
subcosta + radius fused in hindwing almost
to middle of discal cell (usually)
larvae are densely hairy, e.g., woolly bear
ca. 260 NA spp.
Phylogenetic studies suggest tiger moths are merely a derived lineage from within the Noctuidae