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Brief Summary

    Beetle: Brief Summary
    provided by wikipedia
    This article is about the insect. For the car, see Volkswagen Beetle. For other uses, see Beetle (disambiguation).

    Beetles are a group of insects that form the order Coleoptera, in the superorder Endopterygota. Their front pair of wings is hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 species, is the largest of all orders, constituting almost 40% of described insects and 25% of all known animal life-forms; new species are discovered frequently. The largest of all families, the Curculionidae (weevils) with some 70,000 member species, belongs to this order. They are found in almost every habitat except the sea and the polar regions. They interact with their ecosystems in several ways: beetles often feed on plants and fungi, break down animal and plant debris, and eat other invertebrates. Some species are serious agricultural pests, such as the Colorado potato beetle, while others such as Coccinellidae (ladybirds or ladybugs) eat aphids, scale insects, thrips, and other plant-sucking insects that damage crops.

    Beetles typically have a particularly hard exoskeleton including the elytra, though some such as the rove beetles have very short elytra while blister beetles have softer elytra. The general anatomy of a beetle is quite uniform and typical of insects, although there are several examples of novelty, such as adaptations in water beetles which trap air bubbles under the elytra for use while diving. Beetles are endopterygotes, which means that they undergo complete metamorphosis, with a series of conspicuous and relatively abrupt changes in body structure between hatching and becoming adult after a relatively immobile pupal stage. Some, such as stag beetles, have a marked sexual dimorphism, the males possessing enormously enlarged mandibles which they use to fight other males. Many beetles are aposematic, with bright colours and patterns warning of their toxicity, while others are harmless Batesian mimics of such insects. Many beetles, including those that live in sandy places, have effective camouflage.

    Beetles are prominent in human culture, from the sacred scarabs of ancient Egypt to beetlewing art and use as pets or fighting insects for entertainment and gambling. Many beetle groups are brightly and attractively coloured making them objects of collection and decorative displays. Over 300 species are used as food, mostly as larvae; species widely consumed include mealworms and rhinoceros beetle larvae. However, the major impact of beetles on human life is as agricultural, forestry, and horticultural pests. Serious pests include the boll weevil of cotton, the Colorado potato beetle, the coconut hispine beetle, and the mountain pine beetle. Most beetles, however, do not cause economic damage and many, such as the lady beetles and dung beetles are beneficial by helping to control insect pests.

    Coleoptera Overview
    provided by EOL authors

    Order Coleoptera has the most insect species.Beetles can be found throughout the world and can vary from a millimeter to 75 millimeters in length.They have an open circulatory system that uses fluid instead of blood.Most beetles have two pairs of wings, one pair is hardened and the other pair is membranous.Their antennae are mostly used for their sense of smell.They have spiracles, which are breathing holes on their abdomen.Most beetles feed on plants, but other species are predaceous.Some species are aquatic and have a hard exoskeleton.Some species are sexually dimorphic.This can be seen when males have horns on their head.Most beetles undergo complete metamorphosis.They go through several stages from: the egg, the grub, the pupa, and the adult (also known as an imago).Most beetles have a gland that produces pheromones to attract a mate.Beetles can be found in the fossil record as far back as the Lower Permian.People release beetles to control common pests, for instance, ladybugs are released into gardens to control aphid populations.

Comprehensive Description

Identification Resources

    Coleoptera-Atlas.com
    provided by EOL authors

    The aim of this site is to show the world the beauty and diversity of coleoptera, whilst being accessible to new comers intrigued by their beauty and array, to amateurs who are keen to learn more, and for professionals alike.

    At the time of reading this site has over 6000 species which have all been classified, plus 2000 macrophotos which are constantly upgraded and will give you a new facility for identifying and classifying beetles.

Benefits

    Pollinator
    provided by EOL authors
    Early beetles appear to have been among the primary visitors of primitive flowering plants. An improvement over wind pollination, beetles likely played an important role in the evolution of flowering plants. Many familiar North American plants are pollinated by beetles. For example, plants in the magnolia family, including the eight species that are native to the United States, have flowers that are specialized for beetle pollination. In fact, though magnolia flowers are often described as "primitive" (relatively unchanged from the ancestral type), some researchers have suggested that magnolia flowers are actually quite specialized and have evolved to promote nearly exclusive pollination by beetles. The beetles appear to be attracted by the odor of the flowers - which is sometimes described as unpleasant - as well as their color. They feed on nectar, stigmas, pollen, and secretions of the petals. Other insects appear to be unable to access magnolia flowers at critical times, while stigmas are mature or while pollen is shed. At least some magnolia species, including one species in Mexico, produce heat. Odor, often foul or unpleasant, is thought to act as a primary attractant for many beetle and fly pollinators. Beetle-pollinated plants additionally produce heat. The odor may mimic a food source; the heat is thought to help spread the odor and/or provide a direct energetic benefit to pollinating insects