Introduction || Brief Notes on Insect Taxonomy
Brief Notes on Insect Taxonomy
The number of known insect species approaches to one million. Scientists suppose that about 1.5 Ц 10 million species of insects may live on the Earth. Author of this note described 18 new species of wasp-parasitoids during only one year in the Central Asia. How many species are waiting for their discoverers!
Taxonomy is a scientific means for classification and identification of living objects. To use those objects, you need clearly to distinguish them from others which frequently have small differences. Therefore, the taxonomy is not a calculation of wing number or leg number, as external observer could seem, but it is a kit of tools for identification of species, which have frequently enormous economical importance (direct or indirect). Taxonomists investigate both morphology and physiology, ecology, and other sides of living organism. It is not needed to tell about benefits and damages of insects. Bees Ц honey, wax, and pollination. Silkworm Ц silk. Locust Ц perished harvest. Colorado beetle Ц perished potato harvest. Malaria mosquitoes, Flies, Fleas, etc.
Insects were separated to the Class Insecta in the Phylum Arthropoda. The nearest relations of insects are myriapods (Myriapoda). However, remember that adult insects (imago) have only three pair legs in contrast to other arthropoda (e.g., spiders have four pair legs, myriapods have many).
Below, not all orders of insects are presented, since many insects are difficultly shot in natural habitats, or some species are obtained as not photogenic ones.
These insects have wings, or if there are not, their progenitors had (Examples are: lice (Anoplura), mallophagans (Mallophaga), fleas (Aphaniptera)).
Winged insects are divided into two divisions: with semicomplete metamorphosis - Hemimetabola; and with complete metamorphosis Ц Holometabola.
Briefly, the insects have the complete metamorphosis when larva burst out of ovum is not similar to adult insect (imago), and after development, larva pupates. The pupa is relatively motionless phase, when the internal reorganization is taking place, i.e., a full transformation. From pupa, the winged insect appears. The example of the complete metamorphosis can be seen for butterflies on the page "How to Raise Butterfly".
As to semicomplete metamorphosis, the larva burst out of ovum is very similar to imago, but without wings or with rudimentary wings. The larva is molting and growing. After last molt, the larva develops wings and becomes the imago. The examples of semicomplete metamorphosis are presented below: Orders Orthoptera, Hemiptera, etc.