Scaphoideus

Chen, Fangying & Dai, Wu, 2015, Bicoloratum Dai and Li, a new synonym of the leafhopper genus Scaphoideus Uhler (Hemiptera, Cicadellidae, Deltocephalinae), with description of two new species, Zootaxa 3985 (2), pp. 275-283 : 276

Genus Scaphoideus

Scaphoideus Uhler, 1889:33 . Type species: Jassus immistus Say , by subsequent designation of Distant, 1908: 151.

Hussa Distant, 1908: 68 . Type species: Hussa insignis Distant , by original designation. Synonymised by Barnett, 1977:494. Bolanus Distant, 1918: 18 . Type species: Bolanus baeticus Distant , by original designation. Synonymised by Evans, 1947:243. Bicoloratum Dai and Li, 2011:49. Type species: Bicoloratum pingtungisis Dai and Li. syn. nov.

For the relationships and diagnosis of Scaphoideus see Oman (1949), Barnett (1977) and Viraktamath & Mohan (2004).

Remarks. Scaphoideus was erected by Uhler (1889) and the type species for the genus was designated by Distant (1908). It is a large and morphologically diverse group in which the species of Scaphoideus differ widely in colour and male genitalia.

Although some authors attempted to define the genus, no classification was satisfactory. Ball (1932) divided the species of the genus into three groups based on face color. DeLong (1939) divided it into three distinct subgenera according to male genitalia: (1) the subgenus Lonenus with subgenital plates long and narrow, styles with long and narrow apical processes, aedeagus with dorsal portion distinctive; (2) the subgenus Scaphoideus (= Angenus DeLong ) with subgenital plates narrow, narrowed slightly to rounded apex; (3) the subgenus Latenus with subgenital plates short and broad at base, tapered to sharply apex. Above two classifications were not accepted and used.

Recently, the Oriental species of the genus were divided into three groups according to coloration ( Viraktamath and Mohan, 2004): (1) body ochraceous to brown with a median longitudinal yellowish or whitish stripe extending to folded front wings; (2) body with transverse bands on vertex, pronotum and scutellum; (3) body with dark brown spots or bands on vertex, and longitudinal bands on pronotum and scutellum. However, within each of these color patterns, the male genitalia characters are variable. It appears that different color patterns are homoplasies.

The genus Bicoloratum was erected by Dai & Li (in Li et al. 2011) with B. pingtungisis Dai and Li from Taiwan as its type species and included in Deltocephalinae without a tribal placement specified. Zahniser and Dietrich (2013) included the genus in the poorly defined and polyphyletic tribe Athysanini but also re-defined the tribe Scaphoideini to include Scaphoideus and other genera with relatively narrow, produced heads, reflexed costal veins on the forewing, the head and thorax with ochraceous and ivory markings, profemur row AV reduced, metatibia row PD macrosetae elongate, male genital capsule with tufts of elongate setae, and male genitalia with paired processes arising from the connective. Bicoloratum pingtungisis is consistent with the tribal definition of Scaphoideini and also closely resembles the Oriental species of the genus Scaphoideus , in which the aedeagal shaft is well separated from the connective, attached to the latter by a membrane, and the connective stem bears a pair of processes. Moreover, it also consistent with usual characteristics of the pygofer with subapical tufts of long setae and the subgenital plate triangular and broad basally with several macrosetae in an oblique row. Contrary to the original description of B. pingtungensis , the forewing has a venational pattern similar to that of Scaphoideus , i.e., with branches of R along the costal margin of the forewing distinctly reflexed. Although there are slight differences in male genitalia between Bicoloratum and Scaphoideus , the elongate male style apophyses in Bicoloratum are found in several other species of Scaphoideus with different color pattern, including S. elegantulus , inequalis , insignis , jogensis , orientalis , etc; the paired apical processes of the aedeagal shaft in Bicoloratum are also found in various species with different color pattern, including S. assamensis , jogensis , kirti , knappi , maai , undulatus , vaticus , etc. Viraktamath & Mohan (2004) had previously included an Indian Scaphoideus species with similar color pattern and male genitalia, Scaphoideus bicoloratus Viraktamath & Mohan , in the genus Scaphoideus . Although the wing coloration consistently separates Bicoloratum from Scaphoideus , it is difficult to distinguish Bicoloratum from Scaphoideus based on the external shape and male genitalia. Because we could find no other characters to support recognition Bicoloratum as a valid genus, we treat it as a junior synonym of Scaphoideus Uhler, 1889 .