Trombidiformes 163 



3. /)/v^m/?^5 Berlese, 1 903 



a. Diversipes s. str. 



Type. Disparipes exhamiilatus Michael, 1886 



b. Microdispus VdioXi, 1911 



Type. Microdispiis obovatus Paoli, 1911 



4. Imparipes Berlese, 1903 



a. Imparipes s. str. 



Type. Imparipes hystricinus Berlese, 1903 



b. Heterodispus FsLoVi, 1911 



Type. Imparipes elongatus Tragardh, 1904 



5. Microdispodides Vitzthum, 1914 



Type. Pediculoides amaniensis Oudemans, 1912 



(= Microdispodides wichmanni Vitzthum, 1914) 



6. Pygmodispus Paoli, 1911 



a. Pygmodispus s. str. 



Type. Pygmodispus equestris Paoli, 1911 



b. A Hod is pus VaoVi, 1911 



Type. Pygmodispus (Allodispus) latisternus Faoli, 1911 



7. Variatipes FsLoYi, \9\l 



Type. Disparipes nudus Berlese, 1886 



Discussion: These mites are minute, bizarre creatures, found in moss, 

 soil, and sod samples throughout the world, and on various insects 

 such as Formica and Lasius. One member of this family is a pest of 

 honey bees. Acarapis woodi (Rennie) is the cause of the "Isle of 

 Wight Disease" which is to be found in Europe. This scutacarid in- 

 fests the tracheal tubes of bees and causes the eventual death of the 

 host. The life cycle takes place within the tracheal tubes, although 

 adult mites are to be found crawling through the hair of infested bees 

 whereby they can be transferred from bee to bee. The mite causes 

 injury to the bee by: (1) the parasite living upon the host fluids caus- 

 ing active injury; (2) possibly a toxic secretion; (3) mechanical stop- 

 page of the tracheae which prevents air from reaching the individual 

 organs or cutting off the air supply to-the nerve centers which control 

 the bee's activities. This mechanical disturbance is probably the most 

 important. Since the bees can neither fly nor feed this becomes a nu- 

 trition problem. 



References: 



Hirst, S. 1922. Mites injurious to domestic animals. Brit. Mus. (Nat. Hist.) 

 Econ. Ser., No. 13. 



