Order Facts

Paraneoptera (Acercaria):

Subdivision “new” (new) winged insects with simple metamorphosis, hemimetabolous.

Holometabola:

Complete metamorphosis.

Neuropterida:

Net-veined wings and larvae that are predatory.

Paraneoptera Unifying Trend (not universal):

Modification or reduction of mouthparts toward piercing mouthparts or other highly specialized feeding.

Pscocodea Fact:

Merged order.

Psocodea Booklice Fact:

Found in most terrestrial environments, feed on algae, lichens, fungi, and plants, some live gregariously in small colonies.

Psocodea Barklice Fact:

Eyes touch at midline, jump via abdominal flexion, and ametabolous.

Pscodoea Parasitic Lice Fact:

Permanent ectoparasites, highly host specific, chewing and sucking lice.

Thysanoptera Fact:

Very small, asymmetrical mouthparts, major agricultural pests and vector of plant viruses, some species are predatory instead of phytophagous.

Hemiptera Fact:

>80,000 described species.

Auchenorrhyncha Fact:

Sound production and xylem and phloem feeds, plant pathogen vectors.

Sternorrhyncha Fact:

Complex life cycles, aphids show pathogenesis, and scale insects have extreme sexual dimorphism.

Neuroptera Fact:

Predatory larvae, antlion larvae build pit traps to capture prey, and adults vary in ecology, many predatory, and some feed on pollen or nectar.

Megaloptera Fact:

Aquatic predatory larvae, good water-quality indicator taxa, large-bodied adults, and male dobsonflies have hugely enlarged mandibles used in mating displays/combat.

Raphidioptera Fact:

Females bear a long, needle-like ovipositor, predatory larvae live under bark, and they are restricted to the Northern Hemisphere.

Coleoptera Fact:

Most diverse order in the entire animal kingdom, chewing mouthparts, and complete metamorphosis.

Strepsiptera Fact:

Endoparasites of other insects and females are neotenic (wingless, legless, and remain endoparasitic within the host for life).

Hymenoptera Fact:

>150,000 described species, display haplodiploidy.

What is haplodiploidy?

Unfertilized eggs become haploid males and fertilized eggs become diploid females.

Symphyta Fact:

Saw-like ovipositor for cutting plant tissue, herbivorous, caterpillar larvae.

Apocrita Fact:

Crucial biological control agents.

Lepidoptera Fact:

>160,000 described species.

Trichoptera Fact:

Aquatic larvae build portable cases from silk plus substrate material (or construct fixed silk retreats/capture nets for filter feeding).

Diptera Fact:

>150,000 described species, larvae are legless with a reduced head capsule in the more derived families.

Mecoptera Fact:

Mostly scavengers on dead insects, and in male Panorpidae male genitalia are enlarged and upturned, resembling a scorpions tail.

Siphonaptera Fact:

Secondarily wingless for ectoparasitic lifestyle, piercing-sucking mouthparts, and obligate blood feeders as adults.

Hexapoda:

Three thoracic segments, each with one pair of legs (“six feet”).

Entognatha:

Mouthparts enclosed within head capsule (“inside jaw”).

Apterygota:

No wing ever (“without wings”).

Pterygota:

Wings present, or secondarily lost (“winged”).

Palaeoptera:

Cannot fold wings over abdomen at rest (“Ancient wing”).

Neoptera:

Can fold wings flat over abdomen (“new wing”).

Protura Fact:

Tiny, blind, legs likely serve as sensory structures, and rarely encountered.

Diplura Fact:

Most are predatory, common in grassy or wooded habitats but rarely seen because of minute size.

Collembola Fact:

Have a furcula and collophore, among the most numerically abundant hexapods on Earth and crucial in soil ecosystem.

What is a furcula?

A forked jumping appendage.

What is a collophore?

A ventral tube, roles in water balance/adhesion.

Archaeognatha Fact:

Eyes touch at midline, can jump via abdominal flexion (up to 4 inches), and are ametabolous.

Zygentoma Fact:

Long-lived (3-8 years), domestic species may cause extensive damage to household goods.

What is an unresolved mystery?

The origin of wings.

What are the two hypotheses for the origin of wings?

The paranotal lobe hypothesis and the gill-plate/pleural hypothesis.

Paranotal Lobe Hypothesis:

Wings derived from lateral extensions of the thoracic tergum; flat outgrowths of the body wall initially for gliding.

Gill-Plate/Pleural Hypothesis:

Wings derived from modified leg structures, possibly derived from gills of aquatic ancestors; supported by some comparative gene-expression data.

Ephemeroptera Fact:

Adults are short-lived, aquatic naiads are excellent water-quality indicator taxa, have a subimago state.

What is subimago?

A state in mayflies where they molt one more time after acquiring wings (subimago → imago).

Anisoptera:

Wings held open/horizontal at rest, hindwing broader than forewing.

Zygoptera:

Wings held together over the back at rest, fore- and hindwings similarly shaped.

Polyneoptera:

10 orders, monophyly still debated, “orthopteroid” assemblage, tegmina.

Plecoptera Fact:

Wings fold flat over body, many adults have reduced or non-functional mouthparts, and aquatic nymphs require clean, well oxygenated water (major bioindicator taxa).

Notoptera (suborder Grylloblattode) Fact:

Cold-adapted and species-poor.

Notoptera (suborder Mantophasmatodea) Fact:

One of very few insects erected in the modern era.

Dermaptera Fact:

Cerci used in defense and prey capture, some maternal care.

Orthoptera Fact:

Most diverse polyneoptera, tegmina, and stridulation.

What is stridulation?

Sound production.

Phasmatodea Fact:

Masters of crypsis, leg regeneration across molts, and longest insects.

Embioptera Fact:

Have silk-producing glands, live gregariously inside silk-lined galleries, winged males and wingless females.

Zoraptera Fact:

Tiny, found under bark or in leaf litter, wing polymorphism, and species-poor.

Blattodea (cockroaches) Fact:

Flattened body, ancient lineage, and small fraction are pest species.

Blattodea (termites) Fact:

Eusocial, gut symbionts, and enormous ecological role in decomposition, especially in tropical/subtropical systems.

Mantodea Fact:

Sexual cannibalism occurs but is context-and species-dependent.