Tetricissus, Zhang, 2017

Zhang, Yalin, 2017, New Oriental genera in the family Issidae (Hemiptera: Fulgoromorpha), Zootaxa 4312 (2), pp. 355-367 : 360

Tetricissus gen. nov.

Type species: Tetrica philo Fennah, 1978 ; here designated.

Diagnosis. Tetricissus gen. nov. is superficially similar to the genus Tetrica Stål, 1866 in which the type species T. philo Fennah, 1978 was previously described. In addition to the hindwing characters that separate Sarimini (for Tetrica ) from Kodaianellini to which Tetricissus belongs, it differs from Tetrica by: 1) The lateral margins of frons slightly and roundly enlarged below the compound eyes, but in Tetrica , angularly expanded, the angles being much larger; 2) Forewing with MP vein first separate at basal 1/4, but in Tetrica , the first fork of MP near middle; 3) Clypeus flattened, without carina, in contrast, Tetrica with elevated carina from apex to base.

Description. Head with compound eyes almost as wide as thorax ( Fig. 19 ). Vertex nearly rectangular, obviously broader than long, without median carina, anterior, lateral and posterior margins carinate and elevated; anterior margin truncated, lateral margins slightly inclined inward from top to bottom, posterior margin angularly concave at middle ( Fig. 19 ). Frons roundly widened below antenna, apical margin slightly concave at middle, apical and lateral margins carinate and elevated, median carina elevated from apex extending to near base of frons; frons with apical and lateral areas distributed with numerous inconspicuous tubercles ( Fig. 21 ). Frontoclypeal suture dorsally convex ( Fig. 21 ). Clypeus flattened, without carina ( Fig. 21 ). Rostrum short, reaching midcoxae. Gena in lateral view flattened and oblique, with small protuberance near base ( Fig. 20 ). Pronotum triangular, anterior and posterior margins elevated, anterior margin sharply convex, reaching middle level of compound eyes, without median carina ( Fig. 19 ). Mesonotum smooth, without carina ( Fig. 19 ). Forewings elongate, distinctly longer than width ( Fig. 20 ), with broad hypocostal plate ( Fig. 21 ); forewing broadened at basal 1/3 of costal margin, longitudinal veins obvious and elevated ( Fig. 19 ). Vein ScP+R first separate at basal 1/5, ScP+RA extremely long and sinuate, reaching the apical 1/5 of costal margin, the terminal of RP vein reaching the outer margin of forewing; MP vein first fork near the basal 1/4, MP1+2 straight, fork again at apical 1/5, MP3+4 sinuate, without fork; CuA vein first separates at apical 1/3; the fork of ScP+R vein placed before MP vein, CuA vein last ( Fig. 20 ). Clavus obvious and long, veins Pcu and A1 fused at middle of clavus, the end of clavus reaching the outer margin of forewing, ScP+RA vein reach the same level ( Figs. 19, 20 ); forewing with numerous transverse veins, but not distinct ( Figs. 19, 20 ). Hindwing developed, 3-lobed, longitudinal veins well developed, ScP-R-MP-CuA lobe distinctly wider than A1-Pcu lobe; A2 lobe as wide as A1-Pcu lobe, slightly shorter ( Fig. 23 ). Hind tibia with 2 lateral spines on apical half.

Etymology. The name is an arbitrary combination between two generic names of issids: Tetrica and Issus , indicating that this genus is established on one species from the genus Tetrica , and “ Issus ” is the type genus name of this family. The gender is masculine.

Note. This genus refers to the taxon “ Tetrica ” philo on the molecular phylogeny trees ( Wang et al., 2016). Photos of the holotype of Tetrica fusca Stål, 1870 , type species of Tetrica , are available in Gnezdilov et al. (2015: 90, figs 20–23) for better comparison of the Vietnamese species Tetricissus philo ( Fennah, 1978) .

Figures

FIGURES 19 – 26. Tetricissus philo (Fennah, 1978) n. comb. 19. Adult, dorsal view; 20. Adult, lateral view; 21. Frons and clypeus; 22. Labels; 23. Hindwing; 24. Male terminalia, lateral view; 25. Phallic complex, lateral view; 26. Schemata of phallic complex. Scale bars 19 – 21, 23 = 1 mm, 24 – 25 = 0.5 mm.