A New Species of Oribatoid Mite from Guam with a Key to the Species of the Genus Nasozetes Sellnick 1930 (Acarina, Oribatei)

Abstract

Among mites collected on Guam in July 1946 was a species of Nasozetes found on the breadfruit (Artocarpus altilis). This mite herein described as new is closely related to the typical species, Nasozetes sumatrensis Sellnick (1930), and to Nasozetes choerognathus Willmann (1931b) the only 2 previously described species of this genus which belongs in the family Eremaeidae Willmann (1931a). The main generic character is an unusual sexual dimorphism in which the males possess a prominent anterior extension of the rostrum which is expanded into a circular disc or nose (Figs. A, E & F). This rostral expansion is much reduced in the females of N. sumatrensis and is entirely absent from the females of the new species (Fig. C). There are no descriptions of the females of N. choerognathus; therefore it is impossible to determine if this species exhibits the same type of sexual dimorphism. This condition is not known to be present in any other genus of the oribatoid mites. The author has been able to study this mite through the courtesy of Dr. E. W. Baker, Acarologist, Entomology Research Branch, U. S. Dept. of Agriculture. The material was collected by Dr. H. K. Townes during an entomological survey of Micronesia under the auspices of the U. S. Commercial Co., Honolulu, T. H.