Some Apterygota have traces of abdominal legs; spine-like appendages, attached to the hinder margins of some of the abdominal segments beneath and called styli, may also be present.
Bringing together these facts, the Apterygota may be characterized as Wingless insects having the mouth-parts either exposed and of the chewing type or almost entirely concealed by folds of the cheeks, where they are often slender and probably used for piercing and sucking.
Very few of the Apterygota are of any importance from an economic standpoint, but they are of much interest, being the simplest insects known and throwing some light upon the subject of the ancestry of the insect group.
Janetschek (1969) is of the opinion that, in Apterygota, entognathy is realised after different schemes so it should be interpreted as the result of the parallel but independent evolution of the several groups of Apterygota; the polyphyletic appearence of entognathy in Pterygota seems to support this opinion (cited from Dallai, 1974:148).
Apterygota is considered as being an artificial assemblage of paraphyletic taxa (Moen and Ellis, 1984).
The Apterygota are not found to compose a natural group among the hexapods, based on a cladistic analysis of external and internal anatomy characters (Bitsch and Bitsch, 2000:153).
The name Apterygota is sometimes applied to a subclass of small, agile insects, distinguished from other insects by their lack of wings in the present and in their evolutionary history.
Their first known occurrence in the fossil record is during the Devonian period, 417-354 million years ago.
The composition and classification of Apterygota changed over time.
Urinsekten oder Apterygota ist die traditionelle zusammenfassende Bezeichnung für Fischchen, Felsenspringer, Springschwänze, Doppelschwänze und Beintastler.
Apterygota vormen een onderklasse van de klasse insecten (Insecta) die bestaat uit de volgende vijf orden:
Gli Apterigoti o Atterigoti (Apterygota) costituiscono una sottoclasse di piccoli e agili insetti, caratterizzati dalla assenza di ali, sia nel presente che nella loro storia evolutiva.
Scientific classification: The class of insects is arranged in various ways by different entomologists; the following classification is representative.
The class Insecta is divided into two subclasses: the Apterygota, wingless insects; and the Pterygota, including most insects, the majority of which have wings in the imago form.
The Apterygota are divided into four orders: the Protura, a group of very tiny, blind insects; the Thysanura, that includes the silverfish; the Diplura, a small group that contains the largest of the Apterygota, an insect of the genus Heterojapyx (about 5 cm/2 in long); and the Collembola, that includes the springtail.
IngentaConnect Table Of Contents: Pedobiologia(Site not responding. Last check: 2007-11-03)
Author: Rusek J. Development and progress in Apterygota research in the territory of the former Czechoslovakia: Proceedings of the Xth international Colloquium on Apterygota,
Authors: Dell'Ampio E.; Carapelli A.; Frati F. Myrmecophilic Zygentoma (Insecta: Apterygota) from the ibero-balearic fauna Biogeographic remarks: Proceedings of the Xth international Colloquium on Apterygota,
Author: Rusek J. Laboratory observations on the biology of Xenylla welchi (Collembola:Hexapoda): Proceedings of the Xth international Colloquium on Apterygota,
6th International Seminar on Apterygota - Siena 2002
The 6th International Seminar on Apterygota will be held in Siena on September 13-17, 2002.
The Seminar will be held at the Certosa of Pontignano, a beautiful monastery, 8 km away from the city of Siena, immersed in the heart of the Chianti countryside.
