Phyllocoptes wisconsinensis

Aceria parulmi

Aceria near-campestricola

Phyllocoptes wisconsinensis

Relation: The mites discolor and rust the leaves, also causing some twisting and other deformation.

Type Locality: Madison, Wisconsin

Aceria parulmi, new species

The galls from which the mites came are elongate and finger-like. The galls of ulmi Garman are bead-like.

Type locality: Beloit WI
Collected: July 21
Host: Ulmus americana
Relation to host: the mites produce finger-like upper surface leaf galls.

Garman, on p. 187 of the Twelfth Report of the State Entomologist, Ill. 183, named Phytoptus ulmi, new species, causing galls on leaves of Ulmus americana L., and stating: " - -a slender species, with from 67 to 70 striae. Prongs of the feather-like appendage, three. Length of specimens in alcohol, .17 mm." The common mite forming galls on elm leaves in North America in one with what would be called a 2-rayed featherclaw, but perhaps we can harmonize this with Garman's statement. 

Nalepa, in the 1910 Zoologica, pp. 222 and 223, lists Eriophyes ulmicola Nal., 1890 and E. brevipunctatus Nal., 1889, as causing galls on the European Ulmus campestris (now procera), and on U. pedunculata, respectively.  I have examined mites from bead-like leaf galls on various elms from Alberta, Canada, to the Atlantic coast of North America, from England and from th Island of Cypress. In all of these galls two types of mites appear: one with heavily granular shield and completely granulated rings; the other with nearly smooth shiel and with ring granulations ventral only. But these two types are the same in the position of the dorsal shield setae and in both having the 2-rayed featherclaw. Since they are invariably found together it is my opinion that they all represent Garman's ulmi, with Nalepa's ulmicola as the deutogyne, and brevipunctatus as the protogyne. I am indebted to Dr. R. H. Richens, Commonwealth Bureau of Plant Breeding and Genetics, Cmbridge, England, for specimens from England and Cypress.

Eriophyid Stuies B-13