Download Megaloptera, Neuroptera - UConn

General Entomology EEB 286, University of Connecticut
Fall 2006
Neuropterida
MEGALOPTERA
NAME ORIGIN: Gk. megalo – large, great; pteron – a wing.
INTRODUCTION: Dobsonflies & alderflies. A small endopterygote lineage with only 300 species described
worldwide and about 43 species in North America. Traditionally, the three orders Megaloptera, Raphidioptera, and
Neuroptera were placed together as suborders into a single order, the Neuroptera. Even as separate orders, these
three lineages form a well-supported monophyletic group, the Neuropterida. It has long been assumed that the
Neuropterida is the sister group of the Coleoptera, and now molecular data are giving more support to that
hypothesis.
RECOGNITION:
Larvae:
• aquatic
• large thorax
• lateral abdominal gills
Adults:
• medium to large insects
• usually elongate, beaded antennae
• anal area of HW enlarged
• very soft abdomen
HABITATS: The predatory larvae are found in fresh water, usually in streams and rivers under submerged
rocks. The adults are often seen at lights near their larval habitat. Adults are short-lived and do very little feeding.
They are neither strong nor fast fliers and rarely travel great distances.
COLLECTING: Like most endopterygote larvae, the immature tissues must be properly fixed before the larvae can
be placed into alcohol. Large corydalid larvae should be placed in very hot water prior to placing them in alcohol.
The adults can be collected into alcohol. If pinned, the larger Megaloptera should be supported with temporary cards
so they will dry straight.
TAXONOMY: There are only two families: the Sialidae (alderflies) and the Corydalidae (dobsonflies). Sialids are
smaller, usually under 2 cm in length, and hold their wings roof-like over the body (like a trichopteran). Corydalids
are large, sometimes exceeding 8 cm, fold their wings flat over their body; males of Corydalus frequently have
greatly extended mandibles. In Connecticut we have 6 - 8 species of Megaloptera.
Family: Sialidae (alderflies)
• ocelli absent in adults
• 4th tarsal segment dilated and deeply bilobed
• dark-colored insects, 25 mm or less in length
• larvae with 7 pairs of lateral filaments and 1 terminal filament
Family: Corydalidae (dobsonflies and fishflies)
• ocelli present in adults
• 4th tarsal segment cylindrical
• large, soft-bodied insects, usually larger than 25 mm
• some species strongly sexually dimorphic: males with enlarged mandibles
sometimes up to 3 times as long as head
• larvae (hellgrammites) aquatic, usually found under stones in streams; often used
as fish bait
• larvae with 8 pairs of lateral filaments, a pair of hooked anal prolegs, and no
terminal filament
General Entomology EEB 286, University of Connecticut
Fall 2006
Neuropterida
RAPHIDIOPTERA
Snakeflies. Probably the sister group of the Megaloptera. There are about 21 species in North America, mostly in
the West. No raphidiopterans occur in eastern North America.
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front legs (not raptorial) arise from posterior
end of elongate prothorax
females with long external ovipositor
both adults and larvae predaceous
larvae terrestrial, usually found under bark
NEUROPTERA
NAME ORIGIN: Gk. neuron – sinew, nerve; pteron – a wing.
INTRODUCTION: Lacewings, duskywings, antlions, and owlflies. The third of the three major neuropteridan
lineages. A medium-sized endopterygote lineage, with ca. 4,600 species worldwide, of which about 400 occur in
North America. Adults of many groups in North America are difficult to identify. The larvae are poorly known.
RECOGNITION:
Larvae:
• terrestrial
• active, predatory
• distinctive sickle-shaped, sucking mandibles
Adults:
• long, many-segmented antennae
• usually two pairs of large, many-veined,
membranous wings
• front and hind wings usually similar in size and
shape and usually held roof-like over the body
HABITATS: Neuroptera occur in a wide variety of habitats. Myrmeleontids (antlions) occur near sand, where
the larvae build pits to capture prey items. Most neuropterans are predaceous and some (green lacewings) are
considered beneficial because of their voracious appetites for aphids and other pests. Many are attracted to lights.
COLLECTING: Those that fly to lights are probably the most readily collected and the distinctive sand-pits that
the antlions make are easily identifiable. The larvae should be placed in hot water prior to placement in alcohol.
Adults may be pinned dry, and their wings may be spread, although this is rarely done. Due to their relatively soft
bodies, permanent storage in alcohol is an alternative method to retain external characters (except color, for which
dry mounting is preferred). In many Neuropterans, it is often helpful to temporarily pin an index card under the
abdomen to support it while the insect is drying.
General Entomology EEB 286, University of Connecticut
Family: Chrysopidae (green lacewings)
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costal crossveins not forked
wings and body usually light green
common on vegetation, often come to light
eggs laid at ends of upright stalks, usually on foliage
both adults and larvae predaceous, feeding principally on aphids
green lacewings produce low frequency sounds by drumming
substrate with tip of abdomen; the sound production is used in
species recognition
Family: Hemerobiidae (brown lacewings)
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some costal crossveins forked
similar to green lacewings but wings brownish and body
generally much smaller
both adults and larvae predaceous
Family: Myrmeleontidae (antlions)
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damselfly-like in appearance but antennae
longer and clubbed
abdomen very elongate and soft
larvae (doodlebugs) with long, sickle-shaped
mandibles; they live at the bottom of a conical
pit in dry sand, feeding on ants and other small
insects that fall into the pit
Family: Mantispidae (mantidflies)
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raptorial front legs arising from anterior portion of
elongate prothorax
mantid-like in appearance but only 2-3 cm in length
adults feeding on smaller insects
larvae parasitic on egg sacs of ground spiders
Family: Ascalaphidae (owlflies)
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dragonfly-like in appearance, but antennae strongly
clubbed, nearly as long as body
larvae similar to those of Myrmeleontidae, predaceous, with
long, sickle-shaped mandibles but do not dig pits; larvae often
cover themselves with dirt or debris
southern US, rare in CT
Fall 2006
Neuropterida