Review of the Chinese species of the genus Varma Distant (Hemiptera, Fulgoromorpha, Tropiduchidae), with description of two new species

Abstract Two new species of Varma Distant, 1906, V. falcata Chang & Chen, sp. n. (China: Guizhou) and V. lobata Chang & Chen, sp. n. (China: Guizhou) are described and illustrated. The female genitalia of four speices including two known species are described and illustrated for the first time. The diagnostic characters of this genus are redefined. A checklist to the species of Varma in China is given. The Keys on male and female genitalia to the Chinese species of Varma are provided.


Introduction
The tropiduchid genus Varma was established by Distant (1906) with Serida fervens Walker, 1857 from Borneo as its type species. He described the second species V. tridens from Sri Lanka. Then Distant (1909) described one species V. obliqua in this genus. Melichar (1914) transferred the genus Varma into Tropiduchidae and placed it in the tribe Tropiduchini, added one species V. distanti from India. Metcalf (1954) and Fennah (1982) recognised the treatment. In China, as the first record of the genus Varma, two species V. gibbosa and V. bimaculata were described by Wang and Liang (2008). Then Men et al. (2010) added one species V. serrata from China. Up to now, seven species have been reported worldwide, of three species recorded in southwestern China.
Much attention were paid to the genus Varma, however, little information has been reported on female genitalia of the genus, especially in species identification. In this paper, two new species V. falcata Chang & Chen, sp. n. from Guizhou (China) and V. lobata Chang & Chen, sp. n. from Yunnan (China) are described and illustrated. The female genitalia of four speices including two known species, V. gibbosa and V. serrata are described and illustrated for the first time, as useful characters for species identification. The diagnostic characters of this genus are redefined. A checklist to the species of Varma in China is given. The Keys on male and female genitalia to the Chinese species of Varma are provided.

Material and methods
External morphology was observed under a stereoscopic microscope and dimensions of characters were measured with an ocular micrometer. Measurements are given in millimeters (mm). Abdomens were removed and macerated in 10% KOH overnight, washed in water and then removed to glycerine. Observations and drawings were done under a Leica MZ 12.5 stereomicroscope. Illustrations were scanned with Canon Ca-noScan LIDE 100 and imported into Adobe Photoshop 8.0 for labeling and plating composition. Photographs of the types were taken with a KEYENCE VHX-1000C. The type specimens are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC).
Morphological terminology follows that of Bourgoin and Huang (1990) and Bourgoin (1993) for male and female genitalia.
Distribution. Oriental region.  Sternite VII with posterior margin formed a narrow and deep pit in middle 1/9; endogonocoxal lobe produced mesad different rods (Fig. 39)
Material examined. No specimen has been collected by the authors. Distribution. China (Xizang). Coloration. General colour yellowish green to stramineous yellow. Head and pronotum pale green to pale tawny. Mesonotum pale green or pale ocherous. Abdomen tawny. Forewings pale yellowish green, basal part with two light brownish spots, around nodal line with light brownish fasciae.
Etymology. The new species is named after the presence of a falcate process at apically inner margin of gonostyli.

Remarks.
This new species is similar to V. serrata Men & Qin, 2010 in external appearance, but can be distinguished from the latter in the gonostyli with a falcate lobe at apically inner margin (with semicircular lobe in serrata) (Fig. 11); posterior margin of pygofer without lobe process near its upper end on right side (with posterior margin with trapezoidal lobe directed caudoventrad on right side in serrata) (Figs 10, 13); apical part of the aedeagus bearing one band process at lateral ventral margin, with one lobe in doral margin, on the right side of the aedeagal shaft with one flexural waviness (in serrata, with apical part of aedeagus bearing a semicircular ribbon-like plate at left side side, on the right side of the aedeagal shaft with a pediform flate plate and wing-shaped lobe) (Fig. 15).
Remarks. For the female species, Sternite VII with posterior margin of V. gibbosa is similar to V. serrata, but can be from the latter in the pit of posterior margin more shallow and relative more broader (more deep and narrow in serrata), left of endogonocoxal lobe triangular, apex obtuse, that of right falculate (that of left thin rods, that of right slender, with one triangular protrusion in the outer edge, in serrata) (Figs 20, 39). Description. Body length (from apex of vertex to tip of forewings): male 9.2-9.5 mm (N = 6), female 11.1-11.8 mm (N = 4). Coloration. General color pale green to greenish-yellow. Vertex, pronotum, mesonotum pale green. Forewings light green, marked with irregular brown spots at the base and middle and around nodal line, with 3-4 ranks of fine speckles and suffused fuscous between apical margin and the first subapical line.
Etymology. The name of the new species results from apex of aedeagus, splitted into two lobe plates.
Remarks. The author examined many species of V. serrata, and then found that the forewings marked with very light irregular brown spots at the base and middle and around nodal line (Fig. 4).

Geographic distribution of Varma worldwide
According to the geographic distribution map, all speices distributed in Oriental region.

Discussion
The female genitalia were generally used for higher taxon in the Tropiduchidae family, such Fennah (1982) as important tribes' characters. However, few characters were used in species identification for the instability of the female genitalia, such as the numbers of teeth of gonapophyses VIII and gonoplace. Fortunately, we found that there are steady specific differences in the endogonocoxal lobe and sternite VII in genus Varma (Figs 17, 20, 36, 39). These characters were used to record new species in Leptovanua Melichar, 1914 (Tropiduchini), Neocatara Distant, 1910 (Tropiduchini) (Fennah, 1970). It seems unclear that these characters are suited to others genus in the tribeTropiduchini for inadequate specimens.