Taxonomy of the genus Peyerimhoffia Kieffer from Mainland China, with a description of seven new species (Diptera, Sciaridae)

Abstract The taxonomy of the genus Peyerimhoffia Kieffer in China was studied. Eight species were recognized, including seven new species that are herein described and illustrated: P. hamata sp. n., P. obesa sp. n., P. sparsula sp. n., P. longiprojecta sp. n., P. brachypodua sp. n., P. yunnana sp. n., and P. shennongjiana sp. n. In addition, P. vagabunda (Winnertz, 1867) is reported for the first time from China. A key to these Chinese species is provided.

We herein follow the redefined concept of Peyerimhoffia from Vilkamaa and Hippa (2005). The taxon is similar to Mohrigia and Cratyna (Spathobdella) Frey in having a group of setae inside the gonostylus, a visible aedeagal margin of the tegmen, and in having slightly elongated necks of antennal flagellomeres. Peyerimhoffia differs in having strongly elongated dorsomesial setae on the gonostylus, and in having strongly angulate margin of tegmen. The species earlier placed in Peyerimhoffia and the species of the Corynoptera crassistylata group sensu Menzel and Mohrig (2000) proved to form a monophyletic group in two cladistic analyses using adult morphological characters Hippa 2004, Hippa and. In the latter, the monophyly was supported by five character states, two of which unique: "Mesial side of gonostylus with additional elongated setae" and "apicoventral part of gonostylus with nonsetose area" .
The concept of Peyerimhoffia sensu Vilkamaa & Hippa was crisized by Menzel et al. (2011) but without any argumentation or analysis. A recent molecular phylogeny of Shin et al. (2013) placed Spathobdella and Peyerimhoffia as sister groups, but of Peyerimhoffia, only the type species was in the ingroup of the analysis. Accordingly, there is no molecular evidence against the monophyly of Peyerimhoffia in the present sense.
The genus has never been recorded from China. In this study, we taxonomically revise the genus based on specimens collected in recent years by Zhejiang A&F University, China. Detailed illustrations, differential diagnoses, distributional information of each species, and a key to the Chinese species are provided.

Material and methods
All specimens were collected by sweeping, malaise trapping, and yellow trapping and were preserved in 75% ethanol. All were mounted on microscope slides in xylol-based Canada balsam after clearing in xylol. The slides were made under a Nikon SMZ1500 stereo microscope. The specimens were observed, measured, and illustrated under a Leica DM2500 microscope. This study was based on males only because most species characteristics of Peyerimhoffia are based on the male morphology, whereas females are not generally identifiable to the species level. The terminology follows Vilkamaa and Hippa (2005). All of the type specimens in this study were deposited at the Institute of Forest Protection, Zhejiang A&F University, Hangzhou, Zhejiang Province, China (ZAFU). Hypopygium with a lobe-like projecting intercoxal area, tegmen slightly and smoothly curved and sclerotized (Fig. 1B)  Apical tooth long (as long as width of gonostylus), tegmen almost truncate on the apical margin with a weak process (Fig. 3A, B) ........... P. sparsula sp. n.
Remarks. Based on the form of the gonostylus, the new species is similar to P. vagabunda (Winnertz, 1867). However, the new species can be distinguished in having an irregularly shaped palp (Fig. 1C), the gonostylus distinctly and mesially constricted on dorsal side, the tegmen slightly and smoothly curved, and a lobelike projecting intercoxal area on the hypopygium. In contrast, P. vagabunda has a regularly shaped palp, the gonostylus is evenly rounded on the dorsal side, the tegmen is strongly curved, and no lobe-like projecting intercoxal area occurs on the hypopygium.
Remarks. Based on the form of the gonostylus, the new species is similar to P. alpina (Mohrig 1978). However, the new species differs in having palp is 1-segmented, the tegmen is strongly curved and greatly sclerotized, and the intercoxal area is simple in P. obesa. In contrast, in P. alpina, the palp is 3-segmented, the tegmen is slightly curved and weakly sclerotized, and the intercoxal area bears a lobe-like projection.
Distribution. China, Shaanxi (Fig. 9). Remarks. Based on the form of the gonostylus, the new species is similar to P. ultima Vilkamaa & Hippa, 1998. However, the new species can be distinguished by the front tibia with a proximally bordered prolateral patch of modified setae, the gonostylus with few short subapical setae, and the tegmen sub-truncate apically. In contrast, P. ultima has an indistinct row of setae on the front tibia, a gonostylus with numerous long subapical setae, and a tegmen moderately curved apically.
Remarks. This species is unique within the genus in having its tegmen greatly projected in the middle of the apical margin. Based on the form of the gonostylus, it is similar to P. menzeli , but differs in having a very slender fourth flagellomere that is about four times longer than its width and a tegmen that is strongly projected apically. In contrast, in P. menzeli, the fourth flagellomere is about twice longer than its width and the tegmen is truncate apically.
Remarks. This species is unique in having the light-colored gonostylar apical tooth, which is not scleritised.
Remarks. This species can be readily recognized by having two unique characteristics: the gonostylar apex bare, and a dorsally located lobe on its inflated gonostylus.
Etymology. This species is named after its type locality, Shennongjia at Hubei province, China.