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The mite collection of Professor Fain includes more than 100,000 specimens of mites mounted onslides. The species represented in this collection belong to numerous and various groups of mites.This collection also comprises representatives of the 2,500 new species described by ProfessorFain during the 50 years that he spent collecting and studying mites.

Parasites

Most of these mites belong to parasitic groups. They were mainly collected from vertebrates (fromfishes to mammals) and arthropods. Mites are very plastic animals, able to adapt themselves todifferent conditions of life. Most of these species are very small and their body length rangesusually from 0,5 to 1 mm. In the small group of ticks, however, the size is distinctly larger.

Ectoparasitism by mites is very common in vertebrates, especially in birds. In these hosts the miteslive on the skin or in the superficial layers of the skin. About 2,000 species live on feathers (feathermites) but the shafts of the large feathers as well as the feather follicles also harbour mites ofseveral groups. Ectoparasitism is also frequent in mammals but in these animals the feather mitesare replaced by fur mites which attach to the base of the hairs.

Endoparasitism by mites is widely distributed in vertebrates, especially in birds. Most of these miteslive in the respiratory tract of the birds. More than 500 species belonging to 5 different families ofmites have been described from this habitat. All these species are specialized for this habitat andfor their host. Endoparasitism is also common in the other groups of vertebrates: parasitic miteshave recently been found in the swim-bladder of fishes. In toads the nasal cavities harbour a richfauna of mites specialized for this habitat. The lung of snakes is inhabited by mites of the familyEntonyssidae, specialized for these hosts and for this habitat. The mite familyCloacaridae lives inthe cloaca of turtles and some species of this family are frequently found in the body muscles ofthese hosts. Endoparasitism is also well known in mammals. The respiratory tract of Asiatic or

African monkeys is regularly infected by mites of the genusPneumonyssus, highly specialized forthis habitat. In Belgium the mole is parasitized by various mite species among which a tiny andtransparent species (Epimyodex talpae) living in the cellular tissues enveloping the thoracicmuscles.

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Dermatophagoides pteronyssinus (female, ventrally), the "house dust mite".

Human parasites

Man also hosts several parasitic mites. The most common (Demodex) lives in the hair folllicles ofthe face where it feeds on celluler debris or sebum excreted by the hair follicle. This mite, extremelyfrequent and cosmopolitan, is generally well tolerated. Last but not least, there are still two othermite species, very widely distributed and very important to man. The first is a free living mite,Dermatophagoides pteronyssimus (Fig. 1), also called "house dust mite". The normal habitat of this

mite is the mattress, where it feeds and reproduces. The food consists mainly or exclusively ofhuman skin pellicles. The faecal pellets eliminated by the mites and inhaled by a sensitive atopicperson provoke a violent allergic asthmatiform reaction (house dust allergy).

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Sarcoptes scabiei(female, ventrally), the "scabies mite".

Sarcoptes scabiei(Fig. 2) is the agent of sarcoptic mange or scabies in man and animals. This mitehas been identified in all the great epidemics of mange that have occurred in the world during the20th century. Until now all the attempts to eradicate this mite remained unsuccessful. ProfessorFain has extensively studied these two species of mites and provided new morphological andbiological data which have contributed to make the identification and the control of these mitesmore efficient.

Biblography

Fain, A., Gurin, B. & B. J. Hart, 1990, House dust mites Mites and Allergic Disease., Allerbio,Varennes en Argonne, France, 190 pp.

Fain, A., 1968, Sarcoptic mange tude de la variabilit de Sarcoptes scabiei chez l'homme, avecune rvision des Sarcoptidae., Acta Zool. Pathol. Antwerp., 47: 1-96

Fain, A., 1994, Various aspects of the parasitism by mites Adaptation, Specificity and Host-ParasiteCoevolution in Mites., Internat. J. Parasitology, 24 :1273-1283.