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Insect Guide


Ants


All of the true ants belong to the group: Super-family Formicoidea. They are all very characteristic in appearance and there are very few other insects which can be mistaken for them, except possibly the so-called cow-ants, or velvet ants, of the family Mutillidae (super-family Vespoidea), or the so-called white ants, which belong to an entirely different order and which really should not be called ants, if popular names are to coincide at all with scientific classification.

There are almost 9,000 known species of ant in the world and they have a wide variety of lifestyles. For instance the giant Australian Bull Ants which can be over 2.5 cms long, live very simple lives and the Queens and Workers look very similar. In contrast the Leaf cutting ants of Central and South America have a much more complicated social structure in their nests. There can be 3 or 4 different sizes of workers as well as large soldiers, males and Giant Queens and Gynes.

Ants are amazingly successful creatures, on the Ivory Coast in Africa there can be as many as 7,500 colonies of ants per hectare, with an average of around 2,850 ants per colony this adds up 20,000,000 ants per hectare or 2,000 per square metre. Some scientists have estimated that if you weighed up all the animals in the Amazon Basin ants would make up about 30% of the total, and though they are not this successful everywhere it is considered that they might make up as much as 10% of the total animal biomass of the world.

The true ants, however, as shown in the synoptic table, are readily distinguished from all other Hymenoptera, aside from their general and more characteristic appearance, by the one or two swellings on the petiole of the abdomen.

Ants live in communities and are social insects. Social life with certain of the ants is carried to the greatest extreme known in nature. The differentiation into different castes or forms of individuals of the same species is carried to a much higher extent than with the bees and wasps. With the bumblebees there is a separation into two classes of workers, there are large workers and small workers which have different functions in the community. with the ants this becomes almost the rule and when we consider all ants we find that there may be eight distinct castes, not all in the same individual species, though five may occur in the same species.

There are not only the ordinary winged females, the large workers and the small workers (workers major and workers minor, as they are termed), but with certain species there is a well developed and well adapted caste which does the principal fighting for the community and which is known as the soldier.

Carpenter ants create potential pest problems around the United States because they nest in wood, including wood around the house.

Fire ants (Solenopsis), a group of aggressive, stinging ants, pose problems throughout the Southern United States. They build ground nests with dome-shaped tops. Inadvertently stepping on, or near, a nest often results in multiple bites for the unsuspecting person or animal.

Another large group of ants, such as Cornfield Ants, Pharaoh Ants, Lawn Ants and Odorous House Ants, among others, pose problems in and around the house. While all ants bite, generally bites from this group of ants do not pose medical problems.



Cockroaches



The insects of the family, Family Blattidae known commonly as form the old group Cursoria, or runners. The body as a rule is oval and flat, all the legs being similar in form. The head is deflexed or bent under and generally concealed by the prothorax.

The hind wings are slightly folded. The insects of this group are very abundant in the tropics but several species have become spec domesticated and are very abundant in the colder parts of the world. The cockroach type is a very persistent one, and insects of this family cockroaches, existed in great numbers in geologic periods prior to the tertiary. They are found in considerable number in carboniferous rocks and one form has been found in Silurian sandstone.

The eggs are laid in egg cases as with the Mantidae but the subsequent supposed that they grow very slowly. Most of them are nocturnal in their habits. They feed on a great variety of substances, especially those forms which inhabit houses, but it is supposed that their natural food is dead animal matter. Dr. Sharp estimates that there are five thousand species in existence.

The species found in American houses are the American cockroach (Periplaneta americana), the German cockroach or croton bug (Ectobia germanica), the European cockroach or "black beetle" as it is known in England (Periplaneta orientalis) and the Australian cockroach (Periplantea australasiae).

The female carries the egg case with her until she finds a proper place to leave it or until the eggs are nearly ready to hatch. The young roaches grow slowly and pass through a variable number of molts, sometimes as many as seven. The time required for the development from the egg to the adult may be prolonged by absence of food or low temperature. Four or five years have been said to have been occupied in this growth.

The German cockroach has been shown to reach full-growth in from four and one-half to six months and the American cockroach has been raised from the egg to the adult in about twelve months.



Dragonflies


Excepting the butterflies, there are few more attractive and graceful insects than the "dragonfly", as the members of this order are generally termed. They are insects which have always attracted attention, and which are known by a variety of vernacular names, of which dragonfly is the commonest English term.

They are known in some parts of the country as "devil's darning needles" ; elsewhere as "snake feeders" or "snake doctors" ; in Scotland as "flying adders", and in some parts of England as "horse stingers". Although the insects are perfectly harmless, these names well indicate the existence of numerous popular superstitions. Some believe that they will sew up the ears of bad boys; others that they sting horses; still others that they act as feeders and physicians to snakes, especially to water snakes.


The Odonata are slender insects with a very large head which moves most easily upon its slender neck, even rotating to a considerable extent. The eyes are very large, but the antennae are small and short. The wings are elongate, nearly equal in size, and have many veins, both longitudinal and transverse, so that the entire surface of the wing is cut up into many small cells. The legs are placed near the front of the thorax, and all curve forward and are used for grasping the prey of the dragonfly, and never for walking. In fact, the legs are unfitted for walking, although they are used to grasp the twig or other object upon which the dragonfly may rest.

All of the dragonflies are aquatic in their early stages. The metamorphosis is complete in so far that the larva differ radically in appearance from the adults, but the pupa is not quiescent at any time. It is very active, and feeds up to the moment when the final metamorphosis begins. The jaws in all stages are strong, and both larvae and adults are extremely active and are among the strongest and most graceful flyers of all insects. Their flight is so perfect that it has been seriously suggested that flying machines should be modeled after the flight mechanism of these insects.



Flies


All the true flies, that is, those insects which are called flies and have but two wings, belong to the order Diptera. They are the only insects which possess but two wings, with the exception of the males of the scale insects, and a very few May flies (genera Cloeon and Coenis). Some insects in other orders have one pair of wings so greatly aborted that they appear two-winged as in the genus Psectra, one of the Lacewing flies.

The wings are membranous and usually transparent and bear no scales, except in the mosquito family. The hind wings are represented only by two knobbed projections called haltered, or poisers. The metamorphosis is very complete, the larvae being always footless and usually apparently headless maggots and the pupae either some- what resembling those of butterflies and moths, with comparatively free legs and wings, or they are enclosed in the larval skin. Their mouth-parts are formed for sucking. The true flies comprise an enormous number of species.

The most numerous of all of the orders of insects are the Coleoptera, or beetles, the Hymenoptera, which we have just discussed, and the Diptera, and for superiority in point of numbers the precedence must probably be given to the Diptera. About forty thousand species are known and it is estimated that the number yet to be described will bring this number fully up to three hundred and fifty thousand, against three hundred thousand which we have estimated for the Hymenoptera.


Not only have the true flies a superiority in point of numbers, but entomologists are concluding that they probably stand at the head of the insect system in point of evolution, that is to say, they are the most highly specialized of insects. While they do not possess the apparent specialization in the way of intelligence and in other respects seen with the bees, wasps and ants, the very completeness of their transformations and the highly specialized organization of the adults of several families support this view.

The order is not a popular one among entomologists and collectors. Aside from the fact that observations upon their life history are by no means as interesting as some of those which we mentioned in the preceding order, they have none of the beauty which attracts students and collectors to butterflies and moths and they have not the definiteness of structure characteristic of the beetles and they are much more difficult to preserve in collections in perfect condition. The hard-bodied, easily collected, and readily pinned beetles seem much more attractive.



Grasshoppers


The insects of this family are everywhere abundant both in number of species and individuals. They comprise some of the most destructive insects known and the migratory species have devastated the crops of many countries, more especially Russia, portions of South Europe, Algeria, India, Cape Colony, the Argentine Republic and in former years some of the western United States. In the insects of this family the antennae are short, much shorter than the body, the ovipositor of the female is short and composed of four separate plates and the tarsi are three-jointed. The hind legs are the longest and usually have stout femora, especially near the base.

Among the most abundant and injurious species occurring in the U.S. are the western grasshopper or migratory locust (Melanoplus spretus), an insect which damaged western agriculture, especially in the States of Kansas, Colorado, Nebraska and Missouri; the common red-legged locust (Melanoplus femur-rubrum), a species closely resembling the foregoing but having shorter wings; the two-striped locust (Melanoplus bivittatus), a widespread form which is abundant almost every year; the Carolina locust (Dissosleira carolina), the common light-brown species seen so frequently along dusty roads ; the American locust (Schistocerca americana), more abundant in our Southern States where it occasionally becomes very injurious ; and the differential locust (Melanoplus differentialis), a species which has recently done great damage to cotton plantations in Mississippi.

The lubber grasshopper of Florida and Georgia is known as Dictyophorus reticulatus. It varies in color from green to black and has very short wings. It occurs frequently in enormous numbers in the rice-field: near the mouth of the Savannah River, and is an extremely disagreeable object on which to step ; in fact, it reminds one of Thackeray's famous remark when he swallowed his first saddle-rock oyster. The corresponding lubber grasshopper of the Southwest is (Brachystola magna), and is a large greenish species.


Mosquitoes


Mosquitoes belong to the group Family Culicidae. It's not a large group, but a very important one, not only from the fact that mosquitoes abound in so many localities and are great annoyances to man and animals, but also from the fact that they are active agents in the transfer of disease.

They are found in great abundance in tropical regions, in temperate regions and even far to the North. Travelers in Alaska state that the abundance and voracity of the Alaskan mosquitoes is beyond description. They occur with equal abundance in Lapland and in Greenland.

Life History of a Mosquito
(Culex pungens Wiedemann)
This common and widespread mosquito, which occurs from the White Mountains in New Hampshire to Cuba, and from British Columbia to Mexico, lays its eggs, numbering from 200 to 400 in a raft-like mass on the surface of the water. The eggs are laid side by side, standing on end and stuck close together in longitudinal rows six to thirteen in number and with from three or four to forty eggs in a row-, The egg mass is gray-brown from above and silvery white from below, the latter color being due to the water film. The eggs are laid early in the morning before dawn and in warm weather will hatch by two o'clock on the afternoon of the same day.


The larvae are active little creatures known as wrigglers which are so often to be seen in rain- water barrels and horse troughs. The anal end of the body is provided. with a long respiratory tube into which two large air vessels extend, quite to its tip, where they have a double orifice which is guardeded by four claps. This tube issues from the eighth segment of the abdomen. The ninth segment is armed at the tip with four flaps and six hairs. The flaps are gill-like in appearance, though they are probably simply locomotory in function.

The mouth parts are curiously modified and are provided with long cilia which are kept constantly in vibration, attracting and directing into the mouth minute particles of animal and vegetable matter which are to be found in the water. The 'wriggler remains at the surface of the water when breathing through its respiratory tube but descends when seeking for food. It undergoes three different molts, reaches maturity and transforms to a pupa in a minimum of seven days in hot summer weather taking much longer in the early spring or when the weather grows cool in the fall.

The pupa is well illustrated in the accompanying figure and differs radically from the larva or wriggler from the fact that it now breathes from the ear-like or trumpet-like organs issuing from the thorax instead of from a respiratory tube at the other end of the body. The pupa remains at the surface of the water in an upright position but when disturbed wriggles actively to the bottom, bloating upwards again in a very short time. The pupa stage lasts in warm weather but two days, at the expirationof which time the skin splits on the back of the thorax and the adult mosquito works itself out, resting upon the old pupa skin until its wings unfold, and then tales away. The duration of a single generation may be within ten days ; say sixteen hours for the egg, seven days for the larva and two days for the pupa. This time, however, may be indefinitely extended if the weather be cool.



Spider


Spiders are invertebrates, which means they don’t have backbones.  These small creatures help plants reproduce by pollinating them.  They also help recycle dead trees and animals back into the earth.  They are also a vital source of food for birds, fish, and small mammals.  Without invertebrates, like spiders and insects, many other living things would not survive.
Now some serious COOL FACTS about Spiders.
  • Spiders cannot fly. But they can do “ballooning“. Spiders use “ballooning,” to jump between areas. The spider raises its abdomen to release a long thread to catch a breeze, lifting the spider into the air.
  • Male spiders are almost always smaller than the females and are often much more colorful. Some males are so small that they actually look like they’re newly hatched.
  • Spiders are not insects. Insects have three body parts and six legs. Spiders have eight legs and two body parts, the abdomen and the thorax.
  • Spiders eat many types of harmful insects, helping to keep your garden free of pests.
  • Tarantulas is the largest spider in the world. A tarantula will live about 90 percent of its life in a burrow. Tarantulas dig deep burrows and line them with silk webbing, which helps prevent sand and dirt from trickling in. Tarantulas might look creepy, but in a human, a tarantula bite is unlikely to cause problems other than pain at the site.Female tarantula may look mean and fierce.  But they are good spider moms.  They don’t let their young ones out of their sight.  Female tarantulas and many other spiders carry their cocoons  with them.  After the baby  spiders hatch out, the female may carry them on her back for a while. If one spider baby falls off, mom quickly retrieves it.The hairy South American bird spider is a monster of the tarantula family.  One species is ten inches from toe to toe-as big as a dinner plate.This spider eats lizards, birds, even mice!  It dissolves their insides with its venom and then sucks them dry.Tarantulas often live up to twenty years.
  • A strand of spider is said to be stronger than an equal diameter of steel.


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