Female genitalia of Seasogonia Young from China, with a new synonym and a new record (Hemiptera, Cicadellidae, Cicadellini)

Abstract Seasogonia Young, 1986 is a sharpshooter genus with 13 species, four of them recorded from China. In this paper, Seasogonia sandaracata (Distant, 1908) is recorded as new for China and Seasogonia rufipenna Li & Wang, 1992 is regarded as a junior synonym of Seasogonia nigromaculata Kuoh, 1991. The morphological diversity of the female genitalia of Seasogonia is still poorly known. We provide herein detailed descriptions and illustrations of three Chinese Seasogonia species. Notes on the female genitalia of Seasogonia, including intraspecific and interspecific variation, and comparisons between the female genitalia of Seasogonia and of other related genera from China are provided. The preliminary results indicate that the female genitalia may provide useful features for the taxonomy of Seasogonia and other members of the Old World Cicadellini.


Introduction
The sharpshooter genus Seasogonia was established by Young (1986) for nine species (including five new ones), with Tettigoniella dunsiriensis Distant, 1908 as the type species. There was no species recorded from China at that time. Kuoh (1991) described two new species of Seasogonia from China, and later Li and Wang (1992) described an additional one. Kuoh and Zhuo (1996) described another new species, S. sanguinea, which was treated as a junior synonym of S. indosinica (Jacobi) (Cai and Huang 1999). Wilson et al. (2009) included in the genus the species S. sikhimensis (Distant), which was treated as spe-cies of uncertain position by Young (1986). Until now, 13 species are known in the world and four from China. In this paper, S. sandaracata (Distant) is recorded as new for China and S. rufipenna Li & Wang is proposed as a junior synonym of S. nigromaculata Kuoh. The female genitalia have yielded useful characters for the taxonomy of sharpshooters (Nielson 1965, Mejdalani 1998, Rodrigues and Mejdalani 2009, Mejdalani and Silva 2010, but the morphological diversity of the female genitalia is still poorly known compared to our current knowledge of the male genitalia. In the monograph of Young (1986), the female genitalia of Seasogonia species were only briefly described. The present study provides a detailed description of the previously unknown female genitalia of three Chinese Seasogonia species. Notes on the female genitalia of Seasogonia, including intraspecific and interspecific variation, and comparisons between the female genitalia of Seasogonia and of other related genera from China are provided. We hope that this description will point out useful characters for the taxonomic studies on the Old World Cicadellini.

Material and methods
The male and female genital structures were prepared according to the techniques described by Oman (1949) and Mejdalani (1998), respectively. The dissected parts in glycerin were stored in microvials and the microvial was attached below the respective specimen to which the genitalia pars belonged. The morphological terminology of the female genitalia follows mainly Davis (1975) and Nielson (1965). Use of the term gonoplac (=valvula III) and the names for the processes of the dorsal and ventral sculptured areas of the first ovipositor valvula follow Mejdalani (1998). The illustrations of the ventral view of basal region of female genitalia are based on undisturbed and intact female genitalia that the valvulae are not separated. Most of specimens studied are housed in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC), and some are deposited in Shanghai Entomological Museum, Chinese Academy of Sciences (SEMCAS). Abbreviations used in this paper are as follows: AP = articulation point, DE = denticles, LB = lobe, PP = preapical prominence, TO = tooth, VHA = ventral hyaline area, VID = ventral interlocking device. ( (Jacobi), body of male (9.0 mm): 1 dorsal view 2 lateral view 3 ventral view. S. nigromaculata Kuoh, body of male (11.5 mm): 4 dorsal view 5 lateral view 6 ventral view. S. rosea Kuoh, body of male (10.9 mm): 7 dorsal view 8 lateral view 9 ventral view. S. sandaracata (Distant), body of male (11.2 mm): 10 dorsal view 11 lateral view 12 ventral view. rectangular, slightly expanded posteriorly, posteroventral margin angulate; in ventral view (Fig. 34), forming lobes (LB) articulating with valvulae I. Valvifers II (Fig. 29), in lateral view, nearly fusiform, with small group of clustered setae near articulation point (AP). Valvulae I of ovipositor, in ventral view (Fig. 34), with base gradually broadening posteriorly; in lateral view (Fig. 30), shaft distinctly curved dorsally and with dorsal margin concave, with ventral hyaline area (VHA) near apex; dorsal sculptured area located on apical half, broadening to near apex and gradually narrowing to apex, formed by dense scale-like processes; ventral sculptured area restricted to apical portion, formed by dense imbricate processes; ventral interlocking device (VID) distinct on basal 2/3 of shaft; apex of shaft acute. Valvulae II of ovipositor (Figs 31 and 32), in lateral view, slightly expanded beyond basal curvature, distinctly curved dorsally and with dorsal margin concave; apex narrowly rounded; preapical prominence (PP) indistinct; shaft bearing approximately 4-6 teeth (TO) distributed on apical half behind basal curvature; each tooth semiround and bearing few denticles (DE) or not bearing denticles; denticles mostly distributed on dorsal margin of shaft between teeth and on dorsal and ventral margins of apical portion, dentate dorsal margin longer than ventral margin; ducts extending toward dorsal margin and toward apical portion of shaft. Gonoplacs (Fig. 33), in lateral view, with basal half narrow and apical half distinctly expanded; apex rounded.  (Fig. 13), with broad base and gradually narrowed posteriorly, posterodorsal margin concave; apex narrowly rounded; with two or three macrosetae on basiventral portion and many macrosetae on posterior portion; pygofer process (Figs 13 and 14) arising near median-ventral margin, extending dorsally, bifurcate apically and divided into two processes and with small process as 1/3 long as the other one; with dense setae on basal and median portion. Subgenital plate ( Fig. 15) with multiseriate macrosetae on broad basal two-third portion, with uni- seriate macrosetae and some short microsetae on narrowed apical one-third portion. Aedeagus (Figs 16 and 17) broad at basal half and with subrounded median-dorsal process; shaft slender and with paired ventral processes diverging from base of shaft, processes with apex acute and exceeding apex of shaft. Connective (Fig. 18) Y-shaped, stalk short. Style (Fig. 19) Fig. 20) in lateral view, broad and triangular, gradually narrowed posteriorly; with several macrosetae on basiventral portion and many macrosetae on posterior portion; pygofer process arising near median-ventral margin, extending dorsally, bifurcate apically and divided into two processes, short process acute and nearly as 2/3 long as the other one; surface with dense setae except apex. Subgenital plate (Fig. 21) with anterior half broad, surface with multiseriate macrosetae on basal one-half and with uniseriate macrosetae and some short microsetae on posterior half. Aedeagus (Figs 22 and 23) broad at basal half and with angulate median-dorsal process; shaft with acute internal process and with paired ventral processes diverging from base of shaft, ventral processes with apex acute and extending as long as apex of shaft. Connective (Fig. 24) broad, V-shaped. Style (Fig. 25) slightly unciform apically.

Seasogonia nigromaculata
Female genitalia. Abdominal sternite VII (Fig. 35), in ventral view, with posterior margin conspicuously more produced medially than in S. indosinica. Other characteristics as in S. indosinica.   (Fig. 38), in ventral view, nearly as broad as long; anterior margin straight; posterior margin broadly convex. Pygofer (Fig. 39), in lateral view, slightly produced; posterior margin with subacute apex; surface with macrosetae on posterior portion and extending anteriorly along nearly whole of ventral margin. Valvifers I, in ventral view (Fig. 40), not forming lobes articulating with valvulae I. Valvulae I, in ventral view (Fig. 40), much broader than in S. indosinica. Other characteristics as in S. indosinica.

Notes on the female genitalia of Seasogonia
Intraspecific variation. The number of teeth on valvulae II often varied from 4-7 teeth. In addition, the location of each tooth varied among different specimens, or between each valvula of a single specimen.
Interspecific variation. Females of Chinese Seasogonia species can be distinguished from each other mainly by the following characters: (1) the posterior margin of sternite VII is well produced medially and forms a median lobe in S. indosinica (Fig. 26) and S. rosea (Fig. 35), and the latter species has the projection conspicuously more elongated; in S. sandaracata (Fig. 38), the sternite VII is broadly convex and lacks a distinct me- (2) in S. sandaracata, the macrosetae on the pygofer surface extend anteriorly distinctly farther than in the other two species (Fig. 39); (3) the valvifers I, in ventral view, form lobes (LB) articulating with valvulae I in S. indosinica and S. rosea (Figs 34 and 37), and the former species has the lobes slightly larger; S. sandaracata lacks the lobes (Fig. 40); (4) in S. indosinica and S. rosea (Figs 34 and 37), the bases of valvulae I, in ventral view, are more slender than in S. sandaracata (Fig. 40). Other characteristics are little changed.
The female abdominal sternite VII overlaps the bases of the ovipositor and usually has much interspecific variation. Young (1986) stated that the female sternite VII varied from slightly to strongly convex apically. We provide the descriptions and illustrations of sternite VII of Chinese Seasogonia species, and the characters such as lateral and median lobes of posterior margin can efficiently distinguish Chinese Seasogonia species. The female abdominal sternite VII is widely used for separating species of a genus or genera in sharpshooters or several groups of other leafhoppers (Greene 1971, Young 1977, 1986, Krishnankutty and Viraktamath 2008. The ventral view of basal region of female genitalia has been used to discriminate species in a genus of leafhoppers by some other workers (Greene 1971, Leal et al. 2009). Greene (1971) employed the characters of base of the valvulae I for distinguishing species of deltocephaline genus Psammotettix. Based on the present studies, as stated by Greene, the female genitalia characters did not delimit species as precisely as do the aedeagus characters of the male, but the female genitalia such as ventral view of basal region of valvulae I can be used in combination with edge of abdominal sternite VII or other female characters to separate species. Leal et al. (2009) also provided the ventral view of basal portion of female genitalia in sharpshooter genus Scoposcartula and discovered the new characters on base of the valvulae which named prevalvifer area and the sclerotised wall. The present study revealed the occurrence of peculiar lobes articulating with valvulae I, which can be added to the combination of features that distinguish species in the genus.
Comparative notes on Seasogonia and other related genera from China. In the present paper, the previously unknown female genitalia of three species of Seasogonia from China were described and illustrated for the first time. Seasogonia is apparently closely related to the genus Sochinsogonia Young, 1986 in appearance, but in Sochinsogonia the posterior margin of the sternite VII is concave, whereas it is convex in Seasogonia; in addition, the valvulae I and valvulae II are distinctly curved dorsally in Seasogonia and not so in Sochinsogonia (Young 1986).
Unfortunately, we did not have at hand specimens of Sochinsogonia. Thus, we compared the female genitalia of Seasogonia with those of some other related genera from China (Figs 41-64). Based on the female genitalia, Seasogonia can be distinguished from other Old World Cicadellini by the following combination of characters: (1) the posterior margin of the sternite VII is distinctly convex (26, 35 and 38); (2) the valvulae I and II are distinctly curved dorsally (Figs 30,31,41 and 53); (3) the dorsal sculptured area of valvulae I and the teeth of valvulae II are distributed only on the apical half of shaft; the valvulae I have a ventral hyaline area (VHA) near apex (Figs 30 and 41); only a small number of teeth is present on valvulae II (Figs 31, 32 and 53); (4) the dorsal and ventral sculptured areas of valvulae I are formed by dense scale-like processes that are not arranged in oblique lines (Figs 30,41 and 42). It is important to mention that a considerable amount of morphological diversity is observed in the valvifers I, the base of valvulae I and the shape of teeth of valvulae II (Figs 54, 56, 58, 60, 62 and 64). The structure of the valvulae II of Seasogonia seems very unusual for Cicadellini in general. We compared the shape and teeth with other cicadellines, but found little similarities on our studied genera of Old world Cicadellini. Young (1977) illustrated valvulae II of many New World genera. We found that the valvulae II of Seasogonia are somewhat similar to the New World genus Versigonalia (Young 1977, Mejdalani 1998). Just as Seasogonia species, the valvulae II are not very expanded beyond basal curvature, shaft just have poorly developed teeth in apical one-third or one-half and apex is narrowly rounded in Versigonalia, but the shaft of valvulae does not curve so distinctly as in Seasogonia and not have clear dentate apicoventral margin.
The sclerites of the genital chamber described by Young (1986) in females of various Cicadellini are the reduced internal sternite VIII. The sclerotized parts of this sternite can provide shape-related characteristics useful for species distinctions in the subfamily (Nielson 1965, Mejdalani 1998, Takiya and Mejdalani 2004, Leal et al. 2009). We did not observe well sclerotized parts of the sternite VIII in the species of Chinese Cicadellini studied, which is consistent with Young (1986). As Mejdalani (1998) indicated, the features of the female genitalia, especially from the valvulae I and II, such as the shaft form and the teeth form and distribution, can be potentially useful taxonomic characters for the sharpshooter taxonomy. The valvulae I and II usually vary in shape, proportion, armature or texture (Dietrich 2005). We compared the valvulae I and II of some Old World species  and concluded that the features of the female genitalia were reliable and useful. The valvulae I can have a straight (Figs 43 and 49), distinctly concave (Fig. 41), or convex or angled to different degrees (Figs 47 and 51) dorsal margin. The dorsal and ventral sculptured areas of valvulae I are arranged in oblique lines (Figs 44,46,48 and 52) or not (Figs 42 and 50). The ventral interlocking device (VID) can extend along the basal 2/3 (Fig. 41) or 1/3 (Fig. 43) of the blade, among other proportions. The apex of valvulae I can be curved ventrally (Figs 48 and 52), dorsally (Fig. 44), or be not curved (Fig. 42). The shaft of valvulae II shows also much diversity. Its dorsal margin can be concave (Fig. 53), straight (Figs 55 and 61), or convex (Figs 59 and 63) to different degrees. The valvulae II may bear a ventral preapical prominence (Fig. 57) or not (Fig. 61). The distribution of teeth on valvulae II can be continuous (Fig. 60) or not (Fig. 64). The form of the teeth can be semiround (Fig. 54), triangular with subequal straight sides (Fig. 60), triangular with longer posterior side (Figs 56 and 62), triangular with flat posterior area (Fig. 58), or of irregular shape (Fig. 64). The preliminary results herein discussed indicate that the female genitalia can provide useful features for the taxonomy of Seasogonia and other members of the Old World Cicadellini.