Beetle ( Coleoptera )

What are beetles?
  1. The main distinguishing characteristic of the Coleoptera (sheath-winged) is the hardened forewings (elytra) six legs and antennae. In some cases the forewings are reduced
  2. "Sheath" refers to the elytra which forms a protective covering over the membranous hindwings and the relatively soft dorsal abdominal wall.
  3. All beetles have complete metamorphoses, i.e. egg-larva (several instars)-pupa- adult. It is that feature, complete metamorphosis, in combination with the elytra which characterizes insects of the order Coleoptera.
  4. In addition to providing food for amphibians, reptiles, fishes, birds and mammals, a role which they share with most other insects, beetles play other important roles in the environment. Many, cantharids, scarabs, byturids, and others, are pollinators). Dung beetles (scarabs, geotrupids, and others) feed on and reproduce in the dung of herbivores, thereby removing millions of tons of dung that would accumulate and destroy valuable pastureland and natural areas. Burying beetles (silphids) inter animal carcasses which are then used as food by the adults and their growing offspring thereby ridding the landscape of carcasses that would otherwise contaminate and foul the environment. Various nest-dwellers (including histerids, trogids, staphylinids) and fur ectoparasites (such as leiodids, leptinines) rid their bird and mammal hosts of parasitic insects, such as fleas, bed bugs, and lice. Some beetles are effective as biocontrol agents which predate plant-feeding insects. Among these are ladybug beetles (coccinellids) which feed on aphids and scale insects. The Vedalia ladybug beetle in California reduced the scourge of the cottony cushion scale (Icerya purchasi). Carabid beetles, such as the "caterpillar-hunters" (Calosoma, Carabus spp.) are often helpful in reducing populations of harmful caterpillars, such as gypsy moth and budworm caterpillars. Firefly larvae (glowworms) eat slugs and snails which damage such crops as tomatoes and lettuce.

by Dr. Lawrence Kaplan.

Source : http://www.coleoptera.org/p1058.htm

Beetles or Coleoptera are one of approximately 30 orders of the class of Insecta. The Order of Coleoptera is in many respects sharply distinguished from other insects and is the favourite subject of study of both, professional scientists and naturalists.

The beetles are the largest order including more species known to science than any other order not only in the Class of Insecta, but also in the entire animal kingdom (Animalia). The most authoritative calculations indicate that already now more than 350,000 species of beetles have been described. Every year approximately 2000 new species are described (Zoological Record). Taking into account that the entire fauna of the earth is considered to include approximately 1,400,000 species it can be stated that beetles constitute more than a quarter of all known animals. Moreover, recent attempts of total collections of insects from several species of tropical trees in the basin of the Amazon River have shown that 50% of beetles found by this method are new (Erwin, 1982; 1997). Faunae from different species of trees are so very different from one another that it is possible to predict discovery of several hundreds of thousands or even millions of beetle species and according to some evaluations up to 7 million species.

Beetles are most abundant in the tropics; but at the same time they have got adapted to life at all latitudes and in nearly every habitat, to feeding on any substances of organic origin. Therefore, beetles are nearly ubiquitous. They have not been found on the Antarctic Continent yet, but inhabit the subantarctic islands, they have not been found in the open sea, but are abundant on sea coasts, they have not been found beyond the boundary of eternal snows, but very interesting species of beetles occur high in the mountains in the summer immediately close to this boundary. Many species of beetles attain large numbers. The above explains why the beetles are so well known. Beetles, as well as cats, dogs and birds are the first animals that a small child who begins to talk, learns to recognize.

Beetles are extremely diverse not only in size and colour, but also in body shape, sculpture of external cover, presence of various outgrowths, etc. Butterflies probably excel beetles in the splendour of colours, however, beetles have no match in the fantastic diversity of forms. Therefore beetles are an inexhaustible source of inspiration for writers, sculptors, artists, ornamenters and pattern-designers. Perhaps for this reason and also due to the extreme simplicity of storage of dead specimens beetles are a favourite object of collecting.

Many species of beetles are serious pests of agriculture and forestry, stored food, wood, leathers, furs, fabric. Other species, vice versa, are disturbed as a result of man's economic activity; they are permanently declining in numbers or become extinct. Some common species of beetles respond sensitively to the state of natural environment and may serve as convenient indicators of anthropogenic pollution. Therefore, knowledge of beetles is indispensable not only to professional zoologists, but also to plant protection specialists, agriculturists, arboriculturists, museum specialists and workers of food processing industry, ecologists, staff of reserves and specialists in many other areas.

All insects are studied by a special field of zoology - entomology. The study of beetles in its turn has long ago become a separate branch of entomology, coleopterology. Accordingly, specialists studying beetles are called coleopterists.

At the Zoological Institute of the Russian Academy of Sciences (hereinafter referred to as ZIN) coleopterology has long and famous traditions. Coleopterological study conducted at ZIN is based upon the Institute's collection containing now not less than 6 million of specimens. The collection was started as early as 1714 by Peter the Great when the Kunstkammer was established. A jump in the development of study of beetles is associated with to the name of E. Menetries, a world-famous entomologist . After him a series of prominent coleopterists including A.F. Moravitz, A.P. Semenov-Tian-Shansky, G.G. Jacobson, A.N. Reichardt, A.A. Richter, E.L. Gurjeva, M.E. Ter-Minasian, and O.L. Kryzhanovsky worked at ZIN.

Source : http://www.zin.ru/ANIMALIA/COLEOPTERA/eng/intro.htm

Classification Of Bugs

This is a guide to the classes and orders of insects and other arthropods.

The Insecta (insects) are a Class of the large anymal Phylum called ARTHROPODA (arthropods) - a name that refers to the jointed limbs. The other major classes of living arthropods (i.e. animals related to insects) include Crustacea (crabs, lobsters, shrimps, barnacles, woodice, etc.), the Myriapoda (millipedes, centipedes, etc) and the Arachnida (scorpions, king crabs, spiders, mites, ticks, etc). In addition there are several minor classes, the Onychophora (velvet worms), Tardigrada (water bears), Pentastomida (tongue worms) and Pygnogonida (sea spiders), all of witch contain somewhat aberrant living forms of uncertain affinities to the any of the preciding groups, and finally the Class of extinct arthropods, the Trilobita (trilobites), known only from their fossil remains. All these animal are characterised by the though outer body-shell or exoskeleton, with flexible joints between the skeletal plates to allow the animal to move.

ClassMain Body RegionPairs Of LegsPairs Of AntennaWings
Crustaceatwo - cephalothorax* and abdomen (some with head and trunkfive or moretwoabsent
Myriaopodatwo - head and trunkmany - one or two per trunk segmentoneabsent
Arachnidtwo - cephalothorax* and abdomenfournone (though palps may resemble antennae or legs)absent
Insectathree - head, thorax and abdomenthreeoneusually present (but many wingless form)
*cephalothorax = fused head and thorax

Each of the Classes of arthropods, including the insects are split into a number of smaller groups, which reflect progressively more detailed structural similarities between the group member. These smaller groups follow a strict hierarchy. The major class division in descending order of size are called Subclass, Order, Suborder, Family, Subfamily and Genus. A Genus is the smallest group of any real importance in the naming of individual species, although in some classifications generic groups may be further spllit into Subgenera. The scientific name of a species includes, first, the Genus to which it belongs and, second, its specific name, e.g. the European Violet Ground Beetle is called
Carabus violaceus, meaning the species violaceus in the Genus Carabus (by convention, generic and specific names are always printed in italics; the generic name spelt with a capital letter and the specific name with a smaller letter). The full classification of insect would be as follow :

PHYLUM :Arthropodaarthropod
CLASS :Insectainsect
SUBCLASS :Pterygotawinged insect
ORDER :Coleopterabeetle
SUBORDER :Adephagacarnivorous beetle
FAMILY :Carabidaeground beetle
SUBFAMILY :Carabinae-
GENUS :Carabus-
SPECIES :Carabus violaceus L.violet ground beetle

The name of author who first describes a species, or recognised of the aurhor's name, is sometimes quoted after the specific name of the animal, in this case L. = Linnaeus (the Swedish naturalist who firmly established the binomial system for naming animal and plant in 1753, and who published the first descriptive account of this particular beetle).

Class Crustacea
Excluding one or two very small groups of shrimps, the crustaceans are split into 9 main Orders, as listed below. They nearly all live in water and range from minute planktonic shrimp-like creatures, such as water flea, to the large, more familiar, crabs and lobsters. Some members of the Isopoda are the only forms that have really invaded the land and most of these are largerly confined to damp places.
ORDERCOMMON NAME
1. BranchiopodaWater Fleas (Daphnia), Fairy, Brine, Tadpole, and Clam Shrimps
2. CopepodaWater Fleas (Cyclops), Fish Lice, Gill Maggots and Anchor Worms
3. OstracodaSeed Shrimps
4. CirrepediaBarnacles
5. StomatopodaMantis Shrimps
6. MysidaceaOpossum Shrimps
7. DecapodaShrimps, Prawns, Lobsters, Crayfish and Crabs
8. AmphipodaFreshwater Shrimps (Gammarus) and Sand Hoppers
9. IsopodaSea Slatters, Water Slatters, Water Lice and Hog Lice
Isopoda: Oniscoidea (part)Woodlice


Class Myriapoda
There are four groups of centipede-like creatures known collectively as myriapods. These are listed here as Orders of the Class Myriapoda, but in many arthropod classification they are given status of separated Classes.
ORDERCOMMON NAME
1. Pauropoda-
2. Symphylia-
3. DiplopodaMillipedes
4. Chilopoda-


Class Arachnid
The arachnids are usually split into 8 main Orders, as listed below.
ORDERCOMMON NAME
1. XiphosuraKing Crabs or Horseshoe Crabs
2. Pseudoscorpiones (=Chernetidae)Pseudoscorpions or False Scorpions
3. ScorpionidaeScorpions
4. PedipalpiWhip Scorpions
5. Solifuga (=Solpugae)Wind Scorpions or Barrel Spiders
6. Opiliones (=Phalangidae)Harvestmen or Harvest Spiders
7. Acari (=Acarina)Mites and Ticks
8. AraneaeTrue Spiders


Class Insecta
The insects are generally sub-divided into 29 Orders. These are listed below describing general characteristics, recognition features and examples of eact Orders.

ORDER

COMMON NAME

SUBCLASSES & FEATURES

1. Thysanura

Bristletails

APTERYGOTA

These are wingless insects and their body structure suggests that they never had wings during their evolutionary history. Young stages resemble the adults – little or no metamorphosis

2. Diplura

Two-pronged Bristletails

3. Protura

-

4. Collembola

Springtails

5. Ephemeroptera

Mayflies

PTERYGOTA

Division EXOPTERYGOTA

These are winged insects, although some have lost their wings during the course of evolution. When present, the wing develop externally and there is no marked change (metamorphosis) during the life cycle. The young stages, called nymph, resemble the adult except in seze and in lacking fully-developed wings – simply metamorphosis.

6. Odonata

Dragonflies

7. Plecoptera

Stoneflies

8. Grylloblattodea

-

9. Orthroptera

Crickets, Grasshoppers and Locusts

10. Phasmida

Stick and Leaf Insects

11. Dermaptera

Earwings

12. Embioptera

Web-spinners

13. Dictyoptera

Cockroaches and Mantids

14. Isoptera

Termites

15. Zoraptera

-

16. Psocoptera

Psocids and Booklice

17. Mallophaga

Biting Lice

18. Siphunculata (=Anoplura)

Sucking Lice

19. Hemiptera

True Bugs

20. Thysanoptera

Thrips

21. Neuroptera

Alder Flies, Snake Flies and Lacewings

PTERYGOTA

Division ENDOPTERYGOTA

These are winged insects, although some have lost their wings during the course of evolution. When present, the wings develop internally (i.e. inside the body of the immature insect) and there is a marked change (metamorphosis) during the life cycle. The young stages are very different from the adults and are called larvae. The change from larva to adult takes place during a non-feeding stage called the pupa (or chrysalis) – complex metamorphosis.

22. Coleoptera

Beetles

23. Strepsiptera

Stylopids

24. Mecoptera

Scorpion Flies

25. Shiponaptera

Flea

26. Diptera

True Flies

27. Lepidoptera

Butterflies and Moths

28. Tricoptera

Caddis Flies

29. Hymenoptera

Bees, Wasps and Ants



Thanks to Dr David Kendall BSc PhD