Eriophyoid mites from Qinghai Province, northwestern China with descriptions of nine new species (Acari, Eriophyoidea)

Abstract Eriophyoid mites from Qinghai Province, northwestern China were studied herein. Up to now, only six species have been reported from Qinghai Province. In field surveys, 17 eriophyoid mite species were collected, among which nine species were found new to science. The new species and their host plants are listed as follows: Acaphyllisa tuberculumae sp. n. on Populus sp. (Salicaceae); Proiectus xiningensis sp. n. on Pinus sp. (Pinaceae); Phyllocoptes beishaniensis sp. n. on Spiraea mongolica Maxim. (Rosaceae); Tetra pruniana sp. n. on Prunus tomentosa Thunb. (Rosaceae) Rupr. (Berberidaceae); Tetra pyriana sp. n. on Pyrus calleryana Decne. (Rosaceae); Tetra simonia sp. n. on Populus simonii Carr. (Salicaceae); Diptacus berberinus sp. n. on Berberis amurensis Rupr. (Berberidaceae); Diptacus mengdaensis sp. n. on Lonicera elisae Franch. (Caprifoliaceae); Rhyncaphytoptus spinus sp. n. on Lonicera rupicola Hook. f. et Thoms. (Caprifoliaceae). Aculops ulmi Hong & Xue, 2005 was re-described.


Materials and methods
In the field, eriophyoid mites were collected by the aid of a hand-lens (30X) from the lower surface of host plant leaves. Eriophyoid mites, together with host plants, were immersed in 75% alcohol and kept in vials. Each vial was marked with the collection data, such as specimen number, collection date, host plant, mite color, location, collector, and mite relationship to host plant. The collection data were also recorded in the collection notebook for further use. The host plants were kept in a plant specimen folder in a dry environment.
Relation to host. Vagrant on terminal part of the needles. No damage to the host was observed.
Etymology. The specific designation xiningensis is from the place name Xining City, where this new species was collected; feminine in gender.

Tetra pyriana
Relation to host. Vagrant on leaf lower surface. No damage to the host was observed. Etymology. The specific designation spinus is from the character of the dorsal opisthosomal microtubercles, spiny, "spina, spinus" in Latin; masculine in gender.

Discussion
Although Qinghai has climate, vegetation and biological diversity similar to Tibet, we did not find any eriophyoid mite species already reported in Tibet (Song et al. 2011). On the contrary, 6 of 23 species were reported from Gansu Province or Shaanxi Province, east neighboring provinces. As of 2010, 932 eriophyoid mite species have been described from China , and the number is still increasing. Qinghai has about 8% of the land of China, but only about 2% eriophyoid mites were reported to date. Furthermore, only two investigations have been conducted. More systematic collections of eriophyoid mites from Qinghai Province are needed in the near future.