Yunnantettix variabilis Zha & Wen

Zha, Lingsheng, Wen, Tingchi, Boonmee, Saranyaphat & Eungwanichayapant, Prapassorn D., 2016, Notes on the genus Yunnantettix Zheng (Tetrigidae: Cladonotinae), with descriptions of two new species from Thailand, Zootaxa 4205 (4), pp. 373-385 : 381-384

Yunnantettix variabilis Zha & Wen , sp. nov.

Figs 6–8

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:492439

Material examined. Holotype—female, Thailand: Chiang Rai, Doi Mae Salong , 20°9'22"N, 99°36'54"E, 1075 m alt, 17 May 2016, coll. Lingsheng Zha . Paratypes: 5 males and 3 female, 800–1300 m alt, in broad-leaved forests along the winding mountain highway in Doi Mae Salong, 15–25 May 2016.

Description. Female. Body size small. Face and vertex covered with numerous fine granules; vertex convex, depressed on either side of median carina anteriorly, about 2.8 times as wide as an eye; anterior margin low, in dorsal view obtusely angled, surpassing far beyond anterior margins of eyes; lateral carinae little folded upwards ( Fig 7 a); median carina conspicuous and protruding in anterior half, while absent in posterior half, on both side paired fossulae presented; in lateral view face slightly oblique, vertex together with frontal costa obtusely rounded and distinctly protruding forward, frontal carinae smooth and straight, nearly not protruding forward between antennal grooves, at last concave at median ocellus ( Fig 7 c); in frontal view, frontal carinae distinctly divergent, scutellum wide and triangular, between antennae 2.0 times as wide as diameter of scapus ( Fig 7 b). Antennae filiform, 16-segmented, inserted between lower margins of eyes, 9–11th segments longest, 4.5 times as long as wide. Eyes globose, very low, not reaching up to lateral margins of vertex; lateral ocelli placed at the middle of inner margins of eyes.

Pronotal disc or very coarse (covered with many bulges, especially two rows of conspicuous, longitudinal bulges presented in most specimens), or a little coarse (bulges low and inconspicuous), or relatively smooth (bulges absent), covered with numerous fine granules. Pronotal disc a little roof-like in anterior half, while nearly at the same level in posterior half; median carina conspicuous, or entire or interrupted into many parts, in lateral view low arcuate in anterior half while undulate or straight in posterior half; anterior margin of pronotum truncated, paired extralateral carinae presented on the frontal border below eyes; prozonal carinae very conspicuous, erected, long and a little contracted backwards. Between sulci, pronotum distinctly concave on both side of median carina, and median carina lamellate with swollen base; humeral angle very inconspicuous (absent), between shoulders paired interhumeral carinae presented which are distinct and parallel; external lateral carinae of pronotum folded upward behind humeral angles, not reaching apex of hind process (reaching about 3/4 of hind femur); posterior angle of lateral lobe of pronotum extending oblique backwards, apex truncate and anterior margin of apex rounded, posterior margin of each lateral lobe with two concavities; hind process wedged, reaching variably from base of knee to slightly surpassing top of hind femur, apex wide and distinctly triangularly concave. ( Fig 6 )

Tegmen ovate, apex rounded-sharp, 2.15 times as long as wide, not reaching abdomen ( Fig 7 d, e); visible part of tegmen narrow and long, sometimes it’s wholly invisible in few specimens ( Fig 6 a); hind wing vestigial, invisible, nearly triangular, base wide and apex rounded, only 0.5 times as long as tegmen, most of the area are covered by the tegmen ( Fig 7 d, f).

Fore and mid femora compressed, margins finely serrate, upper margin of fore femur straight while lower margin undulate; upper margin of mid femur weakly undulate and lower margin conspicuously undulate. Hind femur stout, 2.6 times as long as wide; upper and lower margins finely serrate; antegenicular denticle not isolated, apex right angled (3♂ 3♀) or a little sharp (2♂ 1♀); genicular denticle finger-like, extending backwards and apex obtuse; hind tibia a little enlarging from base to terminal part, outer/inner side with 6–7/3–5 spines, margins serrate; first segment of hind tarsus 2.0 times as long as third segment, three pulvilli nearly equal in length, apex of third pulvillus obtuse, apices of first and second pulvilli a little sharp.

Ovipositor: upper valvula about 3.0 times as long as wide, sub-base widest, outer margins of upper and lower valvulae wholly serrate ( Fig 7 g). Subgenital plate nearly as long as wide in fresh specimens, posterior margin truncate, in the middle with a broad triangular protrusion ( Fig 7 h).

Body or yellowish brown, or dark, or dark with yellowish brown pronotal disc. Antennae brown, distal 2–3 segments darker; all tibiae brown, fore and mid tibiae with 3 yellowish brown rings each; lower outer side of hind femur black; lower margin of hind femur spotted with yellowish brown.

Male. Slightly smaller than female ( Fig 6 a). Vertex about 2.4 times as wide as one eye; antennae 15- segmented, 8–10th segments longest; subgenital plate cone-shaped, nearly as long as wide, apex fissured and in lateral view nearly truncate, upper apex on both sides forming into a pair of very short and small spines ( Fig 7 i). Other structures and coloration same as female.

Measurements (in mm). Length of body: male 8.5–9.0, female 10.0–11.0; length of pronotum: male 8.0–9.0, female 9.0–9.8; length of hind femur: male 5.0–5.5, female 6.0–6.5.

Distribution. Thailand (Chiang Rai).

Diagnosis. The new species is similar to Y. bannaensis Zheng (Zheng 1995, 2005 ) and Y. elytratus ( Günther) (Günther 1939 , Shishodia 1991). it can easily distinguish from the former based on obtusely angled anterior margin of vertex and indistinct humeral angles, and from the latter by triangular concavity of apex of hind process and external lateral carina of pronotum distinctly extending backwards and reaching 3/4 of hind femur.

Etymology. The new species’ epithet is derived from Latin words ‘ variabilis ’ (variable), which means structures of pronotal disc of the new species are variable in different individuals.

Ecology and habitats. Individuals of Yunnantettix variabilis sp. nov. inhabited leaf litter of tropical rainforest (Doi Mae Salong) in Northern Thailand, and they prefer shades of trees instead of exposing under the sun, and live in the open air and dry place ( Fig 8 ). They feed on humus of leaf litter. Around the localities there are no stream, and they can also adapt to drought even extreme high temperature, because one locality had burnt off seriously ( Fig 8 c), and specimens collected from it resemble black carbon, which seems to having been burnt off by fire. Provided with extremely degenerate wings, they are flightless, instead with very developed hind femora, they jump rapidly for 1–2 meters. They live with Epitettix obtusus and several Bolivaritettix spp..

According to our observations and experiences, adults of the new species cannot be found after August of the year, so we infer they occur only in the dry seasons, while with the rainy season’s coming they will disappear thoroughly. From adult occurrence period and environment of inhabits, together with rotation between dry season and rainy season in Northern Thailand, we infer they reproduce one generation per one year, and they lay eggs in soil which will go through the whole rainy reason before hatching.

Figures

FIGURE 6. Yunnantettix variabilis sp. nov.. a) oblique view of male body; b) dorsal view of female body; c) lateral view of female body. Scale bars 1 mm.

FIGURE 7. Yunnantettix variabilis sp. nov.. a) dorsal view of female head; a) frontal view of female head; c) lateral view of female head; d) lateral view of female tegmen and hind wing after uncovering pronotum; e) entire view of female tegmen; f) lateral view of female hind wing after uncovering the tegmen on it; g) lateral view of female subgenital plate and ovipositor; h) ventral view of female subgenital plate; i) lateral view of male subgenital plate. Scale bars 0.5 mm.

FIGURE 8. Habitats of Yunnantettix variabilis sp. nov.. Pictures were photographed by Lingsheng Zha in Thailand, Chiang Rai Province, Doi Mae Salong, 800 – 1300 m in May 17, 2016.