Three new species of eriophyoid mites (Acari, Eriophyoidea) associated with Lauraceae in China

Abstract In this paper, three new species of eriophyoid mites in the family Eriophyidae associated with Phoebe hunanensis Hand.–Mazz. (Lauraceae), namely Gammaphytoptus striatilobus sp. n., Phyllocoptes setalsolenidion sp. n., and Dechela phoebe sp. n. are described and illustrated. All are vagrants causing no apparent damage to the same host plants.


Introduction
Eriophyoidea is the lineage most highly adapted for plant feeding among the Acari. Among the vast array of eriophyoid taxa, patterns varying from narrow to extreme host specificity are far more prevalent, and repeatedly independent, than in other groups of phytophagous mites (Lindquist 1996a).
During July 2013, field surveys were conducted in Zhangjiajie National Forest Park of Hunan Province. We found three species from the same host Phoebe hunanensis Hand.-Mazz. (Lauraceae), this plant is native to South China naturally in the sheltered and moist places in valleys, under forests or by streams (Lee and Wei 1982). The host plant in this study is a shrub with the leaf blade lanceolate, and leaves close to leathery texture (Fig. 1).
So far, no eriophyoid mite species have been described or reported from P. hunanensis. Two species are, however, known from other Phoebe species, which are Bucculacus phoebus Huang, 2001a and Phyllocoptruta hungmaoensix Xue, Cheng & Hong, 2012. Furthermore, seven of the nine recognized Gammaphytoptus species and three Phyllocoptes species are found associated with Lauraceae. A key to known Gammaphytoptus and Phyllocoptes species is given.

Materials and methods
Eriophyoid mites were collected from plants with the aid of hand-lens (30×). Eriophyoids, together with their host plants, were placed in vials and stored in 75% ethanol. Each vial was marked with the following collection data: specimen number, date, host plant species name, colour of living mites, sample location, collector name and relationship of mite to the host plant. Collection data were also recorded in a notebook and examples of host plant parts were kept in a plant specimen folder in a dry environment for further identification and reference.
Relation to host. This species is vagrant on lower part of the leaf surface. No damage to the host plant was observed.
Differential diagnosis. This new species is similar to Phyllocoptes machilus Wei, Xie & Chen, 2006, but can be differentiated from the latter mainly by possessing: prodorsal shield lacking median, admedian and submedian lines (with median line incomplete, present on the anterior and rear 1/5 respectively, admedian lines complete, forming a network in P. machilus); anterior shield lobe acuminate, ending in a sharp point (with small frontal lobe in P. machilus); femur having fine granules (femur smooth in P. machilus) and tarsal empodium 8-rayed, tarsal solenidion seta-like (tarsal empodium 4-rayed, tarsal solenidion knobbed).
Differential diagnosis. This new species is very similar to Dechela epelis Keifer, 1965, but some quantitative characters can be used to separate them (Table 1).