A new genus of the tribe Issini (Hemiptera, Fulgoromorpha, Issidae) from China

Abstract Macrodarumoides petalinus, a new genus and species of Issidae (Hemiptera) are described based on specimens from Yunnan and Guangxi, China.


Introduction
Issidae are small insects (about 5mm to 20 mm) generally with a stocky body and usually brownish in color, few bright; and some have pronounced maculae. Issid planthoppers and ladybirds exhibit considerable similarity in general especially in the stocky body form. Issids are all plant feeders, with both nymphs and adults intaking phloem fluid from young branches and sometimes roots. Feeding of issids can result in the yellowing of plant foliage. At high population, issids can seriously affect plant growth (personal observation). Although they often have developed wings, some of them like to crawl and jump in shrubs, rather than to fly (personal observation). The family includes 973 species in 155 genera (Gnezdilov 2010). Gnezdilov (2009) considered that the presence of the trilobed hind wing was an insufficient character for defining the tribe Thioniini, and therefore treated Thioniini Melichar, 1906 as a junior synonym of Issini Spinola, 1839. According to Gnezdilov (2003aGnezdilov ( , 2009, the subfamily Issinae consists of four tribes: Hemisphaeriini Melichar; Parahiraciini Cheng & Yang; Issini Spinola and Colpopterini Gnezdilov. In the present paper, a new genus and species, Macrodarumoides petalinus gen. et sp. n., from China is described and illustrated. Based on the hemispherical body, the claval suture on tegmen, the trilobed hind wings and the not-dilated legs, Macrodarumoides gen. n. is placed in the tribe Issini, which has the only species Macrodarumoides petalinus sp. n. from China.

Materials and methods
The terminology of the head, body and male genitalia follows Chan and Yang (1994), and the terminology of the female genitalia follows Gnezdilov (2003b). The genital segments of the examined specimens were macerated in 10% KOH and observed in glycerin jelly using a Leica MZ125 stereomicroscope. Photographs of the specimens were made using a Nikon SMZ1500 stereomicroscope with a Q-image CCD. Images were produced using the software Synoptics Automontage. All the specimens studied are deposited in the Entomological Museum of Northwest Agriculture and Forestry University of (NWAFU) or the College of Life Sciences, Nankai University (NKU), as indicated.
Male genitalia symmetrical; anal segment ( Fig. 10) in dorsal view longer than greatest width; pygofer ( Fig. 9) without spines; aedeagus (Figs 11-13) tubular, symmetrical and shallowly U-shaped, divided distally into a dorsal and ventral lobe, the latter sometimes split, a pair of elongate lateral lobes and a pair of spiniform processes lying ventrolaterally and directed either cephalad or caudad. Genital style (Fig. 9) subtrianglar, apical margin curved and arched, basal margin convex near apex and dorsal margin produced into a single process.
Female genitalia with anal segment (Fig. 15) in dorsal view elliptical, length nearly equal to the widest part. Apex of endogonocoxal process without lobe and anterior connective lamina of gonapophyse VIII with 3 teeth in lateral group. First valvula (Fig.  14) with teeth, ninth tergum and third valvula subquadrate. Pregenital sternite (Fig.  16) with apical margin convex at mid. Diagnosis. This genus is similar to Eusarima Yang, 1994 according to body shape and trilobed wings, but can be differentiated by the following characteristics: 1) vertex long, approximately triangular, the latter with vertex short and subquadrangular; 2) wings narrow, netlike and anal lobe rudimentary, the latter, wings broad, longitudinal veins distinct with little cross veins, and anal lobe developed.
Etymology. This generic name "-oides" from Greece suffix refers to the resemblance of this genus to Macrodaruma Fennah. The gender is masculine.
Male genitalia. Anal segment in dorsal view (Fig. 10) distinctly longer than greatest width apically, apical margin strongly convex, lateral margin strongly divergent from base to apex, anal tube situated near middle; in lateral view ventral margin convex at midlength, nearly truncate in distal half (Fig. 9). Pygofer in lateral view with hind margin evenly convex near middle and slightly convex at base (Fig. 9). Phallus in profile shallowly curved with 2 long spiniform processes directed cephalad at midlength. Aedeagus in profile with apex bifurcated (Fig. 11); dorsal lobe (Figs 11,13) in dorsal view tri-lobed near apex, with apical margin slightly concave at mid, lateral margins curved downward and encasing lateral and ventral lobe; lateral lobes in lateral view divided and tapered into fingers (Fig. 11); ventral lobe with apical margin convex and arched at mid, and lateroapical angle rounded in ventral view (Fig. 12). Genital styles in lateral view nearly triangular, apical margin curved and arched, dorsal margin produced into one large process near apex; base of process acuminate and apex obtusely rounded in caudal view (Fig. 9).
Female genitalia. Anal segment in dorsal view (Fig. 15) slightly longer than greatest width with lateral margins convex, apical margin convex and arched, anal tube situated at basal half; in lateral view ventral margin concave at base, nearly truncate in distal half (Fig. 14). Ovipositor with anterior connective lamina of gonapophyse VIII curved dorsally, with 5 nearly parallel spines; tooth near lateral margin larger. Gonoplac stout, strongly convex and subquadrate, with apical margin polished (Fig. 14). Pregenital sternite with apical margin distinctly convex at midlength (Fig. 16).
Remarks. This species can be differentiated from Eusarima contorta Yang, 1994 by the following characteristics: 1) vertex long, approximately triangular, the latter with vertex short and subquadrangular; 2) frons only with median carina, the latter with median and lateral carinae; 3) wings narrow, netlike and anal lobe rudimentary, the latter, wings broad, longitudinal veins distinct with little cross veins, and anal lobe developed.
This species resembles Macrodaruma pertinax Fennah, 1978 (Figs 4-6) in shape, but differs from the latter in the following characteristics: 1) lateral margins of vertex and lateral margins of pronotum not elevated, the latter with lateral margins of vertex and lateral margins of pronotum elevated foliately, 2) claval suture present, the latter without claval suture, 3) wing with 3 lobes, the latter with wing not split.
Etymology. The specific name is derived from the Latin word "petalinus", referring to the dorsal lobe of aedeagus being concave with the lateral margin distinctly reflected as a petal.