They have been divided into the most inclusive of the taxonomic groups, called phyla singular phylum from the Greek phylon, meaning tribe or race. For examples, animals with a backbone, insects, snails, starfish, earthworms, roundworms, flatworms, jellyfishes, sponges, and amoebae are members of different phyla. The members of each phylum have certain common characteristics. The largest phylum, Arthropoda, includes animals having a segmented body, bilateral symmetry, paired, jointed appendages, usually terminating in claws, a chitinized exoskeleton secreted by the epidermis and molted periodically, striated muscles, a tubular alimentary canal, a ventral nervous system, and a dorsal heart.
See Article History Alternative Title: Homoptera Homopteran, order Homopteraany of more than 32, species of sucking insectsthe members of which exhibit considerable diversity in body size. All of the Homoptera are plant feeders, with mouthparts adapted for sucking plant sap from a wide assortment of trees and wild and cultivated plants.
Many homopterans cause injuries or destruction to plants, including fruit trees and grain crops, and can be vectors of plant diseases. A few provide secretions or other products that are beneficial and have commercial value.
Most members of the Homoptera fall into one of two large groups; the Auchenorrhyncha, which consists of the cicadastreehoppersfroghoppers or spittlebugs, leafhoppersand planthoppers or fulgorids ; and the Sternorrhyncha, which includes aphids or plant licephylloxeranscoccidsscaleswhitefliesand mealybugs.
Thorn treehopper Umbonia crassicornis. There are certain species of cicadas in Borneo and Java, however, that are 8 cm 3. The large fulgorid or lanternfly can attain this size also.
On the other hand, some of the tiniest scale insects are only 0.
Line scales indicate approximate sizes of insects. Distribution and abundance Although Homoptera species are distributed throughout the world, the relative numbers of individual species vary in a given locale.
Only one cicadid species is known in Great Britain, and fewer than 12 in all of Europe. However, more than cicadid species are known in North Americaand about in Australia.
Lanternfly Lanternaria phosphorea E. Ross The abundance of any species in a given environment depends upon the biotic potential of the insectthe abundance of the food plant, and other factors favourable for development of large populations.
Certain species never reproduce in excessive numbers, while others, considered pests, produce many offspring.
Insect species that feed on available crops or other plants present in quantities sufficient to support them normally develop large populations; for example, the oyster shell scale Lepidosaphes ulmi on fruit trees and ornamentals; the greenbug Toxoptera graminum on wheat; and the potato leafhopper Empoasca fabae on potatoes, beans, and alfalfa.
Grape leafhoppers Erythroneura frequently develop large populations that result in heavy plant losses. Importance Homopterans, because all species feed on sap sucked from plants, often cause injuries or destruction to the plants that nourish them.
When such plants are cultivated crops e. In addition, some homopteran species act as vectors of virus- and bacteria-caused diseases of their plant hosts.
|CLASS ARACHNIDA||The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life.|
The check exerted upon insect pests by other insects is an important mechanism of natural control of populations. Predacious insects feed on small, weak species; parasitic insects live on or in a host and feed at its expense.
Aphids, for example, are parasitized principally by members of the Hymenoptera; two important aphid predators are ladybird beetles and lacewings. Pests also may be controlled by chemical and biological methods e.
The homopterans are responsible for injuring numerous plants of economic importance. Cicadas or dogday harvestflies, sometimes mistakenly called locusts, are well-known pests that have an annual life cycle.
They are characterized by their large size and the strident song of the male. Periodical cicadas emerge every 13 or 17 years in large numbers, swarm in trees, mate, and lay eggs in green twigs. Permanent damage to fruit twigs is caused by the egg deposition slits; when the weakened twigs mature into fruit-bearing limbs, they break under the weight of the fruit, and the crop is lost.
Failures of this sort can be avoided by not planting young fruit trees in years of cicada emergence. Leafhoppers cause various types of plant injury by interfering with the normal physiology of the plant.
The salivary secretion of the potato leafhopper, for example, causes leaf cell hypertrophy that impairs transport of sugars. The resulting sugar accumulation in the leaves destroys chlorophyll and causes the leaves to turn brown and die.Homopteran: Homopteran, (order Homoptera), any of more than 32, species of sucking insects, the members of which exhibit considerable diversity in body size.
All of the Homoptera are plant feeders, with mouthparts adapted for sucking plant sap from a wide assortment of trees and wild and cultivated plants. Blattodea is an order of insects that contains cockroaches and termites.
Formerly, the termites were considered a separate order, Isoptera, but genetic and molecular evidence suggests an intimate relationship with the cockroaches, both cockroaches and termites having evolved from a common ancestor. The Blattodea and the mantises (order Mantodea) are now all considered part of the .
The Odonata are divided into two suborders: Zygoptera (damselflies) -- front and hind wings are similar in shape Anisoptera (dragonflies) -- hind wings are broader near the base than the front wings.
The order Odonata divided into three suborders, Zygoptera (Damselflies), Anisoptera (Dragonflies) and Anisozygoptera (fossil species). These insects characterstically have large, rounded heads. More than a million species of animals have been discovered and named.
They have been divided into the most inclusive of the taxonomic groups, called phyla (singular phylum) from the Greek phylon, meaning tribe or grupobittia.com examples, animals with a backbone, insects, snails, starfish, earthworms, roundworms, flatworms, jellyfishes, sponges, and amoebae are members of different phyla.
Introduction. Odonata are an order of aquatic palaeopterous insects. There are about extant species in just over genera. The modern order is divided into two main suborders: Zygoptera (damselflies) and Anisoptera (dragonflies). The common name "dragonfly" also is used for the whole order.
The three extant suborders are .