Insect Orders


Order Protura (Prot=fist, ura=tail) - Proturans

Proturans are minute whitish creatures that range from half a millimeter to one and a half millimeters in length. Their head is conical and lack antennae and eyes. Their mouthparts, which do not bite, are used to scrape off food particles which are digested when mixed with saliva. The larvae begin with 9 segments and acquire one after each molt until they are an adult with 12 segments. The first three segments have styli which are bristlelike, and the first segment has legs which are held up like antennae and act as sensors.
These creatures are also called hexapods and reside in moist environments such as soil, humus, and bark. Their diet consists of decomposing organic matter and fungal spores.

Links:
The Protura http://www.insect-world.com/main/protura.html
Protura http://www.cals.ncsu.edu/course/ent425/compendium/protura.html
Protura http://www.gypsymoth.ento.vt.edu/~ravlin/insect_orders/protura.html
Protura http://www.inscyclo.com/order/protura.htm
Proturans http://www.ifas.ufl.edu/~insect/misc/proturans.htm




Order Diplura (Dipl=two, ura=tail) - Diplurans

Diplurans are hexapods that are mostly similar to silverfish and bristletails. However, they possess only two caudal filaments and are not covered with scales. They also lack compound eyes, have 1 segmented tarsi, and possess mandibles which are withdrawn into the head. Diplurans have styli on 6 or seven of their segments.
These pale creatures are found in damp places such as in soil, caves, and rotting wood.

Links:

The Diplura http://www.insect-world.com/main/diplura.html

Diplura http://www.gypsymoth.ento.vt.edu/~ravlin/insect_orders/diplura.html

Diplura http://www.inscyclo.com/order/diplura.htm

Diplura http://128.196.42.70/tree/eukaryotes/animals/arthropoda/hexapoda/diplura/diplura.html


Order Collembola (Coll=glue, embola=wedge) - Springtails

This creatures common name, springtail, comes from the forked structure (furcula) that allows them to fly through the air. These whitish hexapods make use of this ability when they are disturbed or when mating. Springtails 3 to 6 mm in length can jump 75 to 100 mm.
Springtails can have as many as eight ommatidia (units of a compound eye) while others are nearly or completely blind. Species of Collembola which are herbivores or carnivores possess mandibles which are concealed within the head. In contrast, some species are fluid feeders and possess styletlike mouthparts. A collophore (tubelike appendage) is found on the first abdominal segment. Its tip holds an eversible sac which is known to play a role in the intake of water.
Most species live in concealed areas such as in leaf litter, decaying logs, and fungi. Other species can be found on the surface of freshwater pools and along the coasts. Most feed on decaying plant material, fungi, and bacteria. However, arthropod feces, pollen, and algae have also been found to serve as food for Collembola.

Links:
The Order Collembola http://www.insect-world.com/main/collembo.html

Collembola http://www.inscyclo.com/order/collembola.htm

Order Collembola http://bluehen.ags.udel.edu/homepage/ento/insectdb/collembo.htm

Collembola http://www.gypsymoth.ento.vt.edu/~ravlin/insect_orders/collembola.html

The Collembola http://web.missouri.edu/~bioscish/coll.html


Order Thysanura (Thysan=bristle, ura=tail) - Bristletails, Silverfish

Silverfish are characteristically identified by their three taillike appendages at the end of their abdomen. They are moderately sized, elongate, flattened, and are covered with scales. They also possess mandibles, compound eyes (absent in some), and ocelli (simple eyes) in some. The tarsi have three to five segments with the taillike appendages located on the last segment. These appendages consist of the cerci and median caudal filament. the abdomen has 11 segments which bear styli.
Most silverfish occur outside and feed on plant materials. They can often be found under rotten logs, leaf debris, and stones. Species that are found indoors usually reside in areas that are damp and dry such as bathrooms and basements.

Links:
The Thysanura http://www.insect-world.com/main/thysan.html
Archaeognatha http://www.cals.ncsu.edu/course/ent425/compendium/archeo.html
Microcoryphia http://www.gypsymoth.ento.vt.edu/~ravlin/insect_orders/microcoryphia.html
Silverfish http://www.colostate.edu/Depts/IPM/natparks/silverfi.html
Silverfish and Firebrats http://bluehen.ags.udel.edu/deces/hyg/hyg-11.htm
Silverfish http://www.ext.vt.edu/departments/entomology/factsheets/silverfi.html


Order Ephemeroptera (Ephemero=short-lived, ptera=wings) - Mayflies

Mayflies are soft-bodied insects which are often identified by their characteristic two or three long threadlike tails. The adults have membranous wings with many veins. These wings are held above the body when the creature is at rest. Most mayflies have large triangular front wings and small rounded hind wings. However, in some, the front wings are elongate and the hind wings are virtually nonexistent.
Mayfly nymphs reside in aquatic areas and differ in their daily behavior. Some our active while others burrow y habit. Their other identifying characteristics (besides the threadlike tails) are the gills that can be found along the abdomen. Subimago stage (occurs between nymph and adult) occurs when a mayfly rises to the waters surface, molts, and flies the short distance to shore landing on vegetation. The next day it molts again to become an adult.
Mating, among adults, occurs during swarming flights. These swarms can range in size from small groups to swarms resembling clouds. The swarms begin as all male until finally females join and are seized by the male. Mating takes place in flight and the eggs are laid on the surface of the water. Often mayflies emerge from the water simultaneously which often causes problems for trains and traffic.
Mayflies are important to the diets of many animals, especially fish. Therefor the number of mayflies can serve as a biological indicator
for their surroundings.

Links:
Mayflies http://www.insect-world.com/main/ephemer.html

Mayflies http://www.ag.ohio-state.edu/~ohioline/hyg-fact/2000/2166.html

Ephemeroptera http://www.cals.ncsu.edu/course/ent425/compendium/mayfly.html

Ephemeroptera http://www.gypsymoth.ento.vt.edu/~ravlin/insect_orders/ephemeroptera.html

Ephemeroptera http://www.inscyclo.com/order/ephemeroptera.htm


Order Odonata (Odon=tooth) - Dragonflies and Damselflies

Odonata are well known as beautiful colorful insects that fly. Damselflies tend to be more delicate and slender. The nymphs are aquatic and the adults generally reside close to the water. At both stages, Odonata are predacious and beneficial to humans. The adults have four wings which are elongate, membranous, and have many veins. They also have large compound eyes which tend to make up most of the head. The antennae are small and bristle like, and the abdomen is elongate. The males have cerci (appendages at the end of the abdomen) which are used for clasping during mating. Odonata possess chewing mouthparts. They range from 20 to over 135 mm in length.
The nymphs are aquatic and use gills to breath. Damselfly nymphs are characterized by their gills which come in the form of three leaflike structures at the end of the abdomen. these nymphs move by undulating through the water. Dragonfly nymph have ridges in the rectum that work as gills. By taking in water via the rectum and expelling it, these nymphs are propelled through their water which is their chief means of locomotion. Both types of nymphs feed on small aquatic organisms and use there segmented labium to catch their prey. When fully grown, the nymph emerges from the water to undergo its final molt. After the final molt it takes about half an hour for the adult to fully expand itself. It then takes two to three days to gain full wing strength and another week until its coloration is fully established. In most cases the males are more brightly colored.
Damselflies have a life span of 3-4 weeks while dragonflies may live as long as 6-8 weeks. Mating occurs in tandem (joined) and this usually occurs during flight. Males are territorial and will often chase off other males from the desired female. Odonata arrange their legs in a basketlike fashion to catch their prey which usually consists of small flying insects.

Links:
California Dragonflies and Damsel Flies http://www.sonic.net/~bigsnest/Pond/Lists/dragons.html
Dragon-flies
http://www.insect-world.com/main/odonata.html
Odonata Photo Archive http://insects.ummz.lsa.umich.edu/Images/Odonata/Odo_picts.html
Dragonflies http://www-marketing.wharton.upenn.edu/~johnc/dragonfly.html




Order Plecoptera (Pleco=twisted, ptera=winged) - Stoneflies

Found near streams or lake shores, stoneflies, are small insects that are usually flattened and drab in color. They have four membranous wings which are occasionally reduced or absent in males. Cerci are present on the three-segmented tarsi and the mouthparts are chewing.
Development in stoneflies is a simple metamorphosis. The nymphs are aquatic, have long antennae and cerci, and have branched gills. Unlike mayfly nymphs, stoneflies lack the middle caudal filament leaving them with only two. Mating occurs in response to acoustic sounds made by drumming the abdomen upon a substrate. The drumming pattern is different for each species.

Links:

The Stone Flies http://www.insect-world.com/main/plecopt.html
American Stonefly Web Page http://www.mc.edu/~stark/american.html
Plecoptera http://www.gypsymoth.ento.vt.edu/~ravlin/insect_orders/plecoptera.html


Order Orthoptera (Ortho=straight, ptera=wings) - Grasshoppers, Crickets, and Katydids

Most in this order are plant feeders and are well known to be troublesome to farmers and their crops. They may be both winged or wingless. If winged, they will have four wings consisting of a leathery front pair and a heavily veined back pair. The body, cerci, and antennae are elongate and some species have a long ovipositor. They have chewing mouthparts and simple metamorphosis.
The Orthoptera are best known for their ability to sing. This is done by stridulation which is rubbing one body part against another. The tympana (oval eardrums) are located either on the sides of the first abdominal segment (short-horned grasshoppers) or at the base of the front tibiae (long-horned grasshoppers and crickets). Each species has a different song which is characterized by its rhythm. Most of the singing is done by the males in order to attract the females. The female recognizes the species specific song and approaches the male. In some cases, the male sings an aggressive song if his territory is being invaded by another male.

Links:

Cricket Science http://www.cricketscience.com/
Grasshoppers and Crickets http://www.ent.iastate.edu/imagegal/orthoptera/
How Grasshoppers Jump http://www.st-and.ac.uk/~www_sbms/pers/wjh/jumping/index.htm
Grasshoppers and Crickets http://www.insect-world.com/main/orthopta.html


Order Phasmida (Phasma=phantom) - Walkingsticks and Leaf Insects

In the midwest, species of phasmida are elongate and sticklike with wings either reduced or absent. They are slow-moving herbivorous insects which use mimicry (their twiglike appearance ) to protect themselves. They can emit a foul smelling order which is also used as a means of defense. Walkingst cks can regenerate lost legs and when they are
numerous can cause great damage to trees.
The egg stage is overwinter and often hatch two years after they are laid in the spring. The generation lasts one year. Walkingsticks begin greenish in color but turn brownish as they mature.

Links:

The Stick-Insects http://www.insect-world.com/main/phasmida.html
Phasmida http://www.gypsymoth.ento.vt.edu/~ravlin/insect_orders/phasmida.html
Phasmatodea http://www.cals.ncsu.edu/course/ent425/compendium/stick.html
Order Phasmida http://bluehen.ags.udel.edu/insects/descriptions/phasmida.html


Order Dictyoptera (Dicty=net, ptera=wings) - Cockroaches and Mantids

Cockroaches are known to be fast runners and poor flyers. They are flattened and their head is concealed by the pronotum. Cerci can vary in length while the antennae are generally long. The eggs are held in capsules known as oothecae which are either deposited right after formation, carried around on the abdomen, or enclosed internally in a uterus. They are considered general eaters and household pests.
Mantids are large creatures with an elongate prothorax and abdomen. Unlike cockroaches, mantids are slow moving and have legs modified with spines to catch prey. Mantids are also considered to be the only insects which can turn their head fully. Their eggs are enclosed in a case known as an ootheca and are deposited onto twigs or grass stems. If no other food is readily available, the nymphs eat each other until one remains. The males are eaten after or during mating and in some species no males have been fond. These creatures are often used for pest control but can become pests themselves when they cannot differentiate between damaging and useful insects.

Links:
The Cockroach Homepage http://www.bio.umass.edu/biology/kunkel/cockroach.html

Dictyoptera http://icdweb.cc.purdue.edu/~herbertm/dictyoptera.html

The Dictyoptera http://www.insect-world.com/main/dictyopt.html

Meet the Pest http://www.ns.doe.ca/epb/factsheets/bkyard_bug/cockroach.html

Praying Mantids
http://www.uky.edu/Agriculture/Entomology/entfacts/trees/ef418.htm