THE NEOPTEROUS ORDERS

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THE NEOPTEROUS ORDERS PLECOPTERA (stoneflies)
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Relative Abundance of the Major Insect Divisions
From the phylogenetic tree Endopterygota
Coleopteroids Strepsiptera Lepidopteroids
Dipteroids Hymenoptera Exopterygota
Hemipteroids Paleoptera Orthopteroids Aptery
gota Thysanura Archaeognatha
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First .. Some Classification
Entognatha
Archaeognatha
Zygentoma
Hexapoda
Ephemeroptera
Odonata
Insecta
Plecoptera
Embiodea
Pterygota
Zoraptera
Dermaptera
Grylloblattodea
?
Mantophasmatodea
Orthoptera
Phasmatodea
Blattaria
Isoptera
Mantodea
Neoptera
Psocoptera
Phthiraptera
Thysanoptera
Hemiptera
Coleoptera
Rhaphidioptera
Megaloptera
Neuroptera
Hymenoptera
Mecoptera
Holometabola
Siphonaptera
Diptera
Apterygotes
Strepsiptera
Trichoptera
Paleoptera
Lepidoptera
Hemimetabolous
Holometabolous
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First .. Some Classification
Plecoptera
Embiodea
Zoraptera
Dermaptera
Grylloblattodea
Polyneoptera
?
Mantophasmatodea
Orthoptera
Phasmatodea
Blattaria
Isoptera
Neoptera
Mantodea
Psocoptera
Phthiraptera
Paraneoptera
Thysanoptera
Hemiptera
Coleoptera
Rhaphidioptera
Megaloptera
Neuroptera
Hymenoptera
Mecoptera
Siphonaptera
Diptera
Strepsiptera
Trichoptera
Lepidoptera
Paraneoptera Polyneoptera Hemimetabola
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Aquatic nymphs
Ovipositor lost
Plecoptera
Terrestrial nymphs
Silk glands
Embiodea(Embioptera)
No silk glands
Zoraptera
Dermaptera
prognathous head
Cerci modified to forceps
Cerci not modified
Grylloblattodea
Mantophasmatodea
?
Saltatorial hind legs
Orthoptera
Hind legs not saltatorial
Phasmatodea
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Why arent stoneflies in the Paleoptera?
Similar wing venation
Similar nymphal forms
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Why arent stoneflies in the Paleoptera?
Wing folding
Gill types location
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Classification of Plecoptera
Order Suborder Superfamily Comment
Plecoptera Anarctoperlaria -southern
Hemisphere -very primitive
Arctoperlaria Systellognatha -mandibles of
adult atrophied
Euholognatha -mandibles of adult normal
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Drumming
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Drumming
http//www.cas.unt.edu/StoneflyHome/Contents/Chap
_12/
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General Evolutionary Trends
Originated in cold flowing water
Euholognatha -feed as adults -diurnal -herbivorous
Systellognatha -warmer slower water -carnivorous
(nymphs) -nocturnal
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Hexapod Orders
Plecoptera
Pleco - folded/pleated, ptera - wing
Number of Species
gt2000
Common names
Stoneflies, salmonflies
Typical habitats
fast-moving streams -temperate/boreal climates
Distinguishing characteristics
Adults - hind wings shorter base of hind wing
enlarged and pleated
Nymphs - Body flattened, Tracheal gills behind
the head, at base of legs, or around the anus,
two tails
Other features

• Most primitive of Neoptera