Taxonomic study of the genus Neocarpia Tsaur & Hsu, with descriptions of two new species from China (Hemiptera, Fulgoromorpha, Cixiidae)

Abstract The cixiid planthoppers genus Neocarpia Tsaur & Hsu, 2003 is reviewed. Two new species, N. acutata Zhi & Chen, sp. n. and N. reversa Zhi & Chen, sp. n., are described and illustrated from the southwest of China (Yunnan) to give the genus seven species in total. Female genitalia of four Chinese species are described and illustrated for the first time. A key to all known species of Neocarpia based on male genitalia, and a key to Chinese species (except for N. maai) based on female genitalia, are provided. The morphological characteristics of the posterior vagina, utilized to distinguish female species of Neocarpia, are also discussed.


Introduction
established the cixiid planthopper genus Neocarpia with the type species Neocarpia maai Tsaur & Hsu, 2003 from China (Taiwan), and placed this genus in the tribe Pintaliini of the subfamily Cixiinae (Hemiptera: Fulgoromorpha: Cixiidae). Later, Emeljanov and Hayashi (2007) described N. okinawana from Japan and moved Neocarpia to the tribe Eucarpiini according to hind margin of the forewing without any convexity situated between the clavus apex and icu. So far, five species of Neocarpia are described, including three from China (Tsaur and Hsu 2003;Emeljanov and Hayashi 2007;Löcker et al. 2010;Zhang and Chen 2013).
Herein, two new species of Neocarpia are described and illustrated from Yunnan province, China. Female genitalia of four Chinese species are described and illustrated for the first time. The genus Neocarpia now contains seven species, including five from China. A key to species based on male genitalia, and to Chinese species (except for N. maai) based on female genitalia, are provided. The morphological characters of the posterior vagina are utilized to distinguish female species of Neocarpia.

Materials and methods
The morphological terminology and measurements follow Tsaur et al. (1988) and Löcker et al. (2006) and the morphological terminology of female genitalia follows Bourgoin (1993). Body length was measured from apex of vertex to tip of forewing; vertex length was measured the median length of vertex (from apical transverse carina to tip of basal emargination). External morphology and drawings were done with the aid of a Leica MZ 12.5 stereomicroscope. Photographs of the types were taken with KEYENCE VHX-1000 system. Illustrations were scanned with CanoScan LiDE 200 and imported into Adobe Photoshop CS7 for labelling and plate composition. The dissected male and female genitalia are preserved in glycerine in small plastic tubes pinned together with the specimens.
The type specimens and other specimens examined are deposited in the Institute of Entomology, Guizhou University, Guiyang, Guizhou Province, China (IEGU).
Emended diagnosis. Head slightly narrower than pronotum in dorsal view. Vertex slightly widened to posterior emargination, broader than long and without subapical carina, lateral carinae moderately elevated. Frons with median carina; frontoclypeal suture generally angled or semicircular. Clypeus with well-developed median carina. Rostrum distinctly surpassing hind coxae. Pronotum short with intermediate carinae curved along posterior margins of eyes. Mesonotum tricarinate. Forewing in resting position steeply tectiform, widened towards apex, with rounded apical margin; Sc+R forming a common stem and M emerging separately from basal cell; MA trifid apically; position of fork Sc+R slightly basad or at the same level as fork CuA1+CuA2; first crossvein MP-CuA1 at least as long as MP from M fork to this crossvein, crossvein MP-CuA1 almost at same level as crossvein r-m, subapical cell MP with upper margin (vein MP) fine concave, no crossvein between CuA1 and CuA2. Apical cells 10. Hind tibia lacking lateral spines.
Male genitalia. Pygofer symmetrical and prolonged with symmetrical lateral lobes in lateral view. Medioventral process thumb-like in lateral view. Anal segment tubular, short and stout. Genital styles relative small and symmetrical. Aedeagus slender and flagellum of aedeagus with spinose processes.
Female genitalia. Ovipositor elongate, orthopteroid and slightly curved upwards; anal segment square or rectangular in dorsal view; 9 th tergite without wax plate. Gonapophysis VIII slightly sclerotised, blade-like posteriorly. Gonapophysis IX single, blunt and strongly sclerotised, between middle tooth and apex with a row of denticles. Gonoplac slightly sclerotised, with many spinules on ventral edge in inner lateral view. Posterior vagina with sclerites.
Remarks. This genus may be easily distinguished from other genera of Eucarpiini by the following features: frontoclypeal suture generally angled or semicircular; rostrum distinctly surpassing hind coxae; forewing with ten apical cells, Sc+R forking slightly basad or at same level as fork CuA1+CuA2, first crossvein MP-CuA1 as long as or longer than vein MP from M fork to this veinlet, subapical cell MP with upper margin (vein MP) fine concave, no transverse vein between CuA1 and CuA2, position of first crossvein MP-CuA1 almost at same level as first crossvein r-m (Zhang and Chen 2013).
Distribution. China, Japan, Australia. Dorsal margin of periandrium with one process; flagellum with two processes near apex and without process at base (Emeljanov and Hayashi 2007: Coloration. General color brown (Figs 1-6) (blackish brown in female). Eyes brown, ocelli pale yellow. Vertex generally yellow, carinae brown to dark brown (except median carina milky). Face generally yellow, discal area brown to dark brown. Subapical segment of rostrum blackish brown, apical segment brown with dark brownish apex. Pronotum with discal areas and mesonotum with area between lateral carinae yellow, lateral areas brownish black. Forewing semihyaline, brown throughout; yellow stripes along the Y-veins, the triangle area between the Y-veins brownish black. Hind tibiae pale yellow. Ventral abdomen blackish brown.
Male genitalia. Pygofer (Figs 8,9), dorsal margin shallowly concave and U-shaped ventrally, widened towards apex; in lateral view, lateral lobes triangularly extended caudally. Anal segment (Figs 8, 10), dorsal margin almost straight, ventral margin convex in lateral view, apical margin convex and 1.6 times longer than wide in dorsal view; anal style strap-shaped, not beyond anal segment. Apical margin of genital styles (Figs 8,11) with a small blunt process, dorsal margin bending inwards in the middle. Aedeagus (Figs 12-15) with five spinose processes. Right side of periandrium with a long and broad process, strongly curving near apex directed ventrocephally and a short acute process curved in the middle directed dorsocephally; ventral margin with a small triangular process at basal 1/3, directed ventrocaudally; flagellum moderately sclerotised, generally curved on left side; left side with a short process basally, curved and directed cephalad, and a straight process at apex directed ventrocephally.
Female genitalia. Pygofer (Figs 16-17, 19) moderately sclerotised, with length almost equal to width in caudal view. Anal tube (Figs 16, 18) short, length longer than wide in dorsal view, ventral margin straight in lateral view; anal styles relatively short and small, apical margin semicircular in dorsal view. Gonapophysis VIII (first valvula) (Fig. 20) elongate, and slightly curved upwards, 2/5 of its inner margin sinuate basally. Gonapophysis IX (second valvula) (Fig. 21), distance ratio between middle tooth to apex and length of denticulate portion is 1.72. Gonoplac (third valvula) (Fig. 22) rod-like, 4.2 times longer than wide, with width of spiculated area less than its 1/10. Posterior vagina (Figs 23-24) elongate, at terminal each lateral side with a sclerite respectively in ventral view; with a large transverse sclerite and several small sclerites in dorsal view; a long longitudinal sclerite in ventral view and a much shorter one in dorsal view on left side basally.
Distribution. China (Yunnan). Etymology. The specific name is derived from the Latin word "acutata", referring to the right side of periandrium bearing an acute process in the middle near dorsal margin.
Remarks. Male genitalia of N. acutata sp. n. is similar to N. bidentata Zhang & Chen, 2013, but differs in: (1) right side of periandrium near dorsal margin with a short acute process in the middle curved and directed dorsocephally (in N. bidentata, right side without process in the same position); (2) right side of periandrium with a long and broad process strongly curved near apex directed ventrocephally (process on right side of periandrium near apex straight and directed dorsocephally in N. bidentata); (3) left side of flagellum with a process basally (in N. bidentata, without process in the same position).  Supplementary description. Female genitalia. Pygofer (Figs 25-26, 28) moderately sclerotised, slightly shorter than wide in caudal view. Anal tube (Figs 25, 27) short, slightly longer than wide in dorsal view, ventral margin sinuate in lateral view; anal styles relatively short and small, strap-like. Inner margin of gonapophysis VIII (Fig. 29)

Remarks.
Female of N. hamata is similar to N. acutata sp. n., but differs in: (1) posterior vagina without sclerite near base (posterior vagina with two longitudinal sclerites near base in N. acutata); (2) anal tube shorter than wide in dorsal view (in N. acutata, anal tube longer than wide in dorsal view).
Note. The female genitalia of this species is described and illustrated for the first time.

Distribution. China (Taiwan).
Remarks. Based on the description and the figures by Tsaur and Hsu (2003), this species can be distinguished from other species of the genus by the following charac-ters: ventral margin of periandrium of aedeagus with 2 processes near apex; one process implanted on right side of periandrium near apex; flagellum with sinuate apical margin, a small awl-shaped production protruding on left side near apex.

Distribution. Japan (Ryukyus).
Remarks. Based on the description and the figures by Emeljanov and Hayashi (2007), this species can be distinguished from other species of the genus by the following characters: periandrium bearing two processes on left side and one on right side near apex; dorsal margin of periandrium with one process, directed caudally; flagellum with two processes near apex. Coloration. General color yellowish brown (Figs 43-48) (brown in female). Eyes brown, ocelli yellow. Vertex generally yellowish brown, carinae brown to dark brown (except median carina milky). Face generally yellow, carinae brown to dark brown; rostrum yellowish brown with dark brownish apex. Pronotum and mesonotum with areas between lateral carinae yellow, lateral areas brown. Forewing semihyaline, alternately yellowish brown and pale yellowish brown, with black spots on end of longitudinal veins. Hind tibiae yellowish brown. Ventral abdomen yellowish brown.
Male genitalia. Pygofer (Figs 50, 51), same as N. acutata. Anal segment (Figs 50,52), in lateral view, dorsal margin nearly straight, ventral margin slightly convex, with a horn-like process extending to apex ventrally; in dorsal view 1.8 times longer Distribution. China (Yunnan). Etymology. The specific name is derived from the Latin word "reversa", referring to the left side of the periandrium with a short reversed process basally.  Remarks. Male genitalia of N. reversa sp. n. is similar to N. maai Tsaur & Hsu, 2003, but differs in: (1) left side of periandrium with a short reversed process basally (N. maai without process in same position); (2) two processes on both lateral sides of periandrium near apex (three processes on periandrium near apex, two on ventral margin and one on right side in N. maai); (3) flagellum with smooth apical margin (sinuate in N. maai).

Distribution. Australia (Queensland).
Remarks. Based on the description and the figures by Löcker et al. (2010), this species can be distinguished from other species of the genus by the following characters: right side of periandrium with a process near apex and ventral margin of periandrium with one small triangular process at apical 1/3; flagellum with a prominent long process in the middle.

Discussion
The taxonomic characters of cixiid male genitalia have been sufficiently studied, whereas the descriptions of cixiid female genitalia are quite rare. Although some characters of the female external genitalia like ovipositor, anal segment, anal style and wax plate have been described by several researchers in history, such as: Cixius Latreille (Remane and Asche 1979), Hyalesthes Signoret (Sforza and Bourgoin 1998), Trirhacus and related taxa (Holzinger 2002) and Oteana Hoch (Hoch 2006), these morphological characters are reported only reliable in taxonomic identifications on genus level or higher category, applying them in species identifications is often impracticable Löcker et al. 2006). Nonetheless, using the characters of female inner genitalia structures, especially those such as the sclerites on the walls of the posterior vagina may provide a practical way for the species level identifications of the female cixiids (Bourgoin 1993;Holzinger et al. 2002;Orosz 2013).
Tsaur and Hsu described and illustrated the female pygofer and the anal segment of Neocarpia maai (Tsaur and Hsu 2003). Löcker et al. (2010) reported the morphological characters of the ovipositor, the 8 th abdominal sternite, the anal segment and the anal style of N. rhizophorae. However, these characters are not effective when used to distinguish among species of Neocarpia. Combined with the type specimens of Neocarpia, we found that the characteristics of posterior vaginal walls (32)(33)(41)(42)(65)(66) can be considered as key diagnostic features for female species identification and might provide evidence for the species diagnosis for other Neocarpia and Cixiidae. The variety of sclerites in numbers, sizes, and shapes in the walls of the female posterior vagina may be of high potential value in species identification in Cixiidae. In future study, we suggest that the morphological characters of the posterior vagina should be given more attention and their effectiveness in species identifications can be better evaluated and explored through more descriptions and illustrations of this structure.