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Taxonomy and Phylogeny

The animals are divided into:
(a) belonging to the emperor,
(b) embalmed, (c) tame, (d) sucking pigs, (e) sirens,
(f) fabulous, (g) stray dogs,
(h) included in the present classification,
(i) frenzied, (j) innumerable,
k) drawn with a very fine camelhair brush,
(l) et cetera, (m) having just broken the water pitcher,
(n) that from along way off look like flies.

Jorge Luis Borges, " THE ANALYTICAL LANGUAGE OF JOHN WILKINS"
Works in 3 volumes (in Russian). St. Petersburg, "Polaris", 1994. V. 2: 87.

 

Borges invented an excellent fantastic example of an absolutely useless classification having a number of faults. The worst of these are several unrelated reasons of the classification and intercrossing of taxa separated in the classification. Actual classifications of beetles are certainly devoid of such obvious drawbacks, but they are far from being ideal. The most vulnerable point in the known systems of the order Coleoptera is selecting characters for separation of taxa at different nodes of the classification tree and establishing criteria for taxonomic categories of different ranks.


A good classification in the first turn should be useful giving an opportunity to reduce the enormous number of species existing in nature to an observable number of groups of species. Such classification is particularly important for beetles. The number of beetle species described approaches 400,000, and about several millions await their description. As is seen from the above diagram, beetles constitute approximately one quarter of all known living organisms on the Earth. It is even difficult to imagine such tremendous number. Modern classifications (or systems) of the order of Coleoptera include approximately 150 families. This is a quite observable number. A good specialist on beetles remembers characters and external appearance of representatives of approximately 100 families. Manipulating with names of these 100 taxa it is much easier to talk with colleagues and find the needed chapter in a key or a catalogue and to get one's bearings in a large collection. It would be difficult to imagine these actions, if a coleopterist had to operate with names of 350-400 thousand species, which no one can remember.


The rules of building classifications (or systems of taxa) are the subject of a special division of zoology - systematics. To be able to talk about classification seriously it is important to understand clearly at least two terms - a systematic category and a taxon. One more issue to be understood is that any classification is subjective and conventional. Only species exist in nature. Combining of these species is the result of man's speculation. Thus, systematic (or taxonomic) category is a general term to denote one of the levels of joining species in a classification. Similar species are joined into genera, close genera into families, similar families into orders, orders into classes, classes into phyla, phyla of all animals are joined in one kingdom Animalia. Listed here are only the major obligatory levels of zoological classification. There are at least forty intermediate levels - intermediate systematic categories. A taxon means a possible placement of concrete species into one systematic category. An "order" is a systematic category and "the order of beetles" is a taxon. A "family" is a systematic category and the family of leaf-eating beetles is a taxon. Because many beetle families comprise a large number of species (thousands and dozens of thousands of species) two systematic categories are of particular importance in their systematics, i.e. a subfamily and a tribe that are between a family and a genus: subfamily and tribe.


The issue of macroclassification of Coleoptera on the levels of order to families was considered by many coleopterists. The best grounded and adopted by many specialists is the system of the order developed by eminent coleopterists Lawrence and Newton (Lawrence & Newton, 1995). This simplified system including only families of beetles occurring in the Palearctic, i.e. in Europe and non-tropical parts of Asia and Africa is of double importance. On the one hand it reflects modern scientific ideas of the system of the order of Coleoptera. On the other hand it is of purely utilitarian importance and should serve as a basis of guides available keys, textbooks and popular books. In this classification we had to give up radical innovations and changes, particularly if they concern generally accepted families of practical importance. This classification is the result of a joint effort. It considers proposals and comments of a number of Russian specialists - O.L. Kryzhanovsky, G.S. Medvedev, A.G. Kirejtshuk, B.A. Korotyayev, S.E. Chernyshev, A.V. Frolov, and others.


For specialists seriously studying macroclassification of Coleoptera of particular interest would be the purely scientific original classification of the order, developed by A.G. Kireichuk and considering the views of the eminent coleopterist of the 20th century Roy Crowson. This classification includes also extinct species of beetles and for the recent families approximate time of their separation in the course of evolution is indicated.


A.L. Lobanov, May 2002.