Taxonomic review of the genus Tambinia Stål (Hemiptera, Fulgoromorpha, Tropiduchidae) with descriptions of four new species from the Pacific region

Abstract Four new species of Tambinia Stål (Hemiptera: Fulgoromorpha: Tropiduchidae), Tambinia conus sp. n. (Papua New Guinea), Tambinia macula sp. n. (Malaysia: Borneo), Tambinia robustocarina sp. n. (Malaysia: Sabah) and Tambinia sexmaculata sp. n. (Australia: Kuranda) are described and illustrated from the Pacific region. The diagnostic characters of this genus are redefined. A checklist and a key to the known species of Tambinia are provided.

Only few papers provided valuable information about Tambinia: Wilson (1986) has stated that the Oriental and Australasian genera Nesotaxila and Kallitaxila appear to be most closely related to Tambinia. Asche and Wilson (1989) have indicated that some similarity exists in the aedeagal structure in Tambinia species and Ommatissus Fieber, 1875 (Trypetimorphini). A cladistic analysis is needed, but is beyond the scope of this paper.
While sorting and identifying Tropiduchidae from material on loan from the California Academy of Sciences, San Francisco, California, USA (CAS), National Museum of Natural History, Smithsonian Institution, Washington, DC, USA (USNM) and elsewhere, we found four new species of Tambinia from Papua New Guinea, Malaysia (Borneo, Sabah) and Australia (Kuranda). A revised generic diagnosis and a checklist of all known species of Tambinia are provided. A key to known species is also updated.

Materials and methods
Dry pinned specimens were used for the descriptions and illustrations. External morphology was observed under a stereoscopic microscope and characters were measured with an ocular micrometer. Abdomens were removed and macerated in cold 10% KOH overnight. Precise dissections and cleaning of genitalic structures were finished in distilled water. Observations and drawings were done in glycerine under a compound light microscope. Photographs of the types were taken with a Nikon Coolpix 5400 digital camera. The digital images were then imported into Adobe Photoshop 8.0 for labeling and plate composition. Line figures were drawn with the aid of a camera lucida mounted on a Zeiss Stemi SV-11 stereomicroscope.
Specimens examined during the course of this study are deposited in the CAS, USNM and Bernice P. Bishop Museum, Honolulu, Hawaii, USA (BPBM). The terminology follows Bourgoin and Huang (1990) and Wang et al. (2009).
Discussion. The genus Tambinia comprises twenty-four species and is distributed in Oriental, Australasian and Afrotropical regions (Distant 1906, 1916, Fennah 1956, 1970, 1982, Ghauri 1976, Matsumura 1914, Melichar 1914, Metcalf 1946, 1954, Muir 1931, Wilson 1986, Wilson and Malenovský 2007. The tropiduchid planthoppers are usually weak fliers and have poor ability for long-distance migration by themselves. So, we indicate that new species have formed through geographical isolation over the disjunct distribution of the genus across widely separated island groups. In external appearance, the genus Tambinia is similar to the Oriental and Australasian genera Nesotaxila, Kallitaxila and Kallitambinia. These four genera form a distinct group within tribe Tambiniini. They can be distinguished from the other known genera in the tribe by the head relatively dorsoventrally depressed, produced in front of eyes, but not extreme produced into a linguiform prolongation, apex not broadly rounded to base of frons, and hind tibia with two lateral spines. The four genera can be distinguished as follows: Frons about as long as broad, forewings with two black elongate spots near bases of sutural margins, nodal line marked with several fuscous spots (see Distant, 1906: 278 Fig. 3   a pair of short sublateral carinae basally between median carina and lateral margins; posterior margin straight. Frons (Fig. 2C) longer in middle than the widest breadth (1.4: 1), disc flat and smooth, covered with sparsely microsetae (Fig. 2B); lateral margins sinuous, diverging from apex, slightly concave at level of eyes, then diverging further to reach their widest point before converging to the clypeus; median carina slender, gradually thinning and obsolete posteriorly, almost reaching to frontoclypeal suture. Clypeus (Fig. 2C) triangular, with broad median carina. Pronotum (Figs 1A, 2A) distinctly shorter than mesonotum in midline (0.4: 1), carinae strongly ridged, lateral carinae diverging posteriorly, median carina distinct, reaching posterior margin. Pronotum and mesonotum together medially 2.2 times as long as median length of vertex. Hind tibiae each with 2 distinct lateral spines; spinal formula of hind leg 5-5-2. Forewings (Figs 1A, 2D) relatively elongate and narrow, 2.7 times as long as maximum breadth, with corium smooth, not granulate, Sc+R forking at 2/5 apical, Cu 1 forking after level of junction of claval veins, cell Sc with a short cross vein at its apical angle, with 13 apical cells and 6 subapical cells, claval veins uniting basad of middle of clavus.
Male genitalia. Pygofer (Figs 2F-H) narrow and relatively high, wider ventrally than dorsally, anterior margin moderately concave, posterior margin nearly straight on ventral half in lateral view. Anal tube (Figs 2F, 2G) distinctly elongate, surpassing to apex of gonostylus, ventral margin slightly bent ventrad in lateral view; lateral margins narrowing distad, apical margin distinctly forked in dorsal view; anal styles relatively short and stout, not surpassing apex of anal tube in dorsal view. Gonostylus (Figs 2F, 2H) very narrow, apical part dorsoposteriorly directed in lateral view; median conical process distinctly elongate and strong, sclerotized, nearly reaching to middle part of gonostylus in ventral view. Periandrium (Fig. 2F) distinctly short, ring-shape, with a long process directed caudad at ventral side, surround aedeagusat medially. Aedeagus ( Fig. 2F) with shaft sinuate and apical half dorsoposteriorly directed in lateral view, apical part forking at endosoma, forming two process, which dorsal one distinctly longer than the ventral one; endosoma membranous, slightly expanded. Etymology. This new species is named for the presence of a strong median conical process at apically inner margin of gonostylus (Figs 2F, 2H).
Distribution. Papua New Guinea. Remarks. This species is similar to T. languida Stål, 1859 collected from Sri Lanka, but can be distinguished from the latter in the vertex with two short reddish stripes, pronotum with a pair of orange spots outside lateral carinae, carinae of vertex and pronotum orange, mesonotum with a pair of orange spots beside lateral carinae near posterior margin, forewings with many reddish spots marked from basal part to nodal line and the frons with ratio of median length to the widest breadth 1.4:1 (in T. languida, vertex and pronotum without pigmentation, mesonotum sometimes suffused with ochraceous, the frons with ratio of median length to the widest breadth 2:1, see Stål, 1859: 317;Melichar, 1914: 85). Colour. General colour ocherous, vertex (Figs 1B, 3A) with median carina suffused reddish, the reddish extending from the sides, forming two reddish long stripes, its outer margins irregular, pronotum (Figs 1B, 3A) with a pair of reddish spots at disc depression between median and lateral carinae, frons (Fig. 3C) suffused with pale reddish, forewings (Figs 1B, 3D) with basal portion ocherous, with two red elongate marks near bases of sutural margins, many orange or red spots marked from basal part to nodal line, nodal line suffused with one transverse orange to red band, tips of spines on hind tibiae and tarsi black.

Tambinia macula
Head and thorax. Head (Figs 1B, 3A) projecting before eyes approximately median length of eye, strongly dorsoventrally depressed. Vertex (Figs 1B, 3A) about as long as broad, two times as long as median length of pronotum, anterior margin projected at an obtuse angle in dorsal view, lateral margins ridged and converged anteriorly; median carina thin and percurrent; posterior margin straight. Frons (Fig. 3C) longer in middle than the widest breadth (1.3: 1), disc slightly depressed, covered with sparsely microsetae (Figs 3B, 3C); lateral margins sinuous, diverging from apex, slightly concave at level of eyes, then diverging further to reach their widest point before converging to the clypeus; without median carina. Clypeus (Fig. 3C) triangular, without median carina. Pronotum (Figs 1B, 3A) distinctly shorter than mesonotum in midline (0.3: 1), carinae strongly ridged, lateral carinae diverging posteriorly, median carina distinct, reaching posterior margin. Pronotum and mesonotum together medially 2.1 times as long as median length of vertex. Hind tibiae each with 2 distinct lateral spines; spinal formula of hind leg 5-5-2. Forewings (Figs 1B, 3D) relatively broad, with basal portion semihyaline, thicker than apical portion, without granulation, 2.7 times as long as maximum breadth, Sc+R forking about medially, Cu 1 forking after level of junction of claval veins, cell Sc with a short cross vein at its apical angle, with 12 apical cells and 5 subapical cells, claval veins uniting distad of middle of clavus.

Distribution. Malaysia (Borneo).
Remarks. This species is similar to T. atrosignata Distant, 1906, but can be distinguished from the latter in vertex with two reddish long stripes, pronotum with a pair of reddish spots, forewings with basal portion ocherous, with two red elongate marks near bases of sutural margins, many orange or red spots marked from basal part to nodal line and nodal line suffused with one transverse orange to red band. Colour. General colour tawny yellow, forewings (Figs 1D, 4D) with two fuscous elongate marks near bases of sutural margins, nodal line suffused with pale brown marks, many fuscous spots marked from nodal line to apex, tips of spines on hind tibiae and tarsi black.
Male genitalia. Pygofer (Figs 4E-G) irregular subquadrate in lateral view, anterior margin concave on dorsal 1/3, posterior margin produced caudad in lateral view. Anal tube (Figs 4E, 4F) relatively elongate, ventral margin slightly bent ventrad in lateral view; lateral margins convex medially then narrowing distad, apical margin slightly concave in dorsal view; anal styles relatively long and narrow, surpassing apex of anal tube in dorsal view. Gonostylus (Figs 4E, 4G) elongate, but not surpassing to apex of gonostylus, apical half narrow and basal half broad in lateral view; median conical process very small, sclerotized in ventral view. Periandrium (Fig. 4E)  Etymology. This new species is named for the presence of a robust median carina on the vertex (Figs 1D, 4A).
Remarks. Based on the following combination of characters: head relatively short, not strongly dorsoventrally depressed, broadly produced anteriorly; vertex with median carina strongly thickened and broad; pronotum with median carina relatively broad and frons with basal part of median carina strongly broad and thickened, this species and the four previously described species, T. menglunensis, T. rubrolineata, T. similis and T. theivora form a very distinct group within Tambinia.
In external appearance, this species is similar to T. similis (Fig. 1C) and but differs from the latter in the median carina on vertex long and percurrent, thickened and broad, but not spatula-like, forewings relatively broad, nodal line relatively near middle and cell Sc without a short cross vein at its apical angle. This species is also similar to T. menglunensis (see Men and Qin, 2009: 263, Figs 1, 2), but differs from the latter in the obsolete spots and markings on the vertex, pronotum, mesomotum and forewings, median carinae on vertex, pronotum and frons strongly thickened and broad, and gonostylus with median conical process very small. Tambinia sexmaculata sp. n. urn:lsid:zoobank.org:act:56274E10-6B5F-41CC-9DB7-563446EC4CD2 http://species-id.net/wiki/Tambinia_sexmaculata Figs 1E, 5A-H Description. Body length (from apex of vertex to tip of forewings): ♂ 6.2 mm (N=1), ♀, 6.6-6.8 mm (N=2).
Colour. General colour tawny yellow, vertex (Figs 1E, 5A) with six red spots, genae ( Fig. 5B) with orange patch between eye and lateral margin of frons, forewings (Figs 1E, 5D) with two pairs of red spots near bases of sutural margins and distad of level of union of claval veins, relatively, tips of spines on hind tibiae and tarsi black.
Etymology. This new species is named for the presence of six reddish markings on vertex (Figs 1E, 5A).
Distribution. Australia (Kuranda). Remarks. This species is similar to T. conus but can be distinguished from the latter in the vertex with six red spots, forewings with two pairs of red spots and by the male genitalia structure (Figs 5F-H), especially the shape of anal tube, median conical process of gonostylus relatively small, periandrium relatively long, with a long, sinuate process at left side, dorsoposteriorly directed, and the shaft of aedeagus apical part abruptly curved through approximately 30˚, directed to right.