Tetrix gibberosa ( Wang & Zheng, 1993 )

Ding, Wen-Jing, Ding, Jian-Hua, Zhang, Hai-Jun & Zha, Ling-Sheng, 2021, Taxonomical clarification of Tetrix gibberosa (Wang & Zheng), a high-backed pygmy grasshopper species from eastern PR China (Orthoptera: Tetrigidae), Zootaxa 5082 (3), pp. 278-285 : 279-282

Tetrix gibberosa ( Wang & Zheng, 1993)

Figs. 1–3

( Mishtshenkotetrix gibberosa Wang & Zheng, 1993 )

= Alulatettix bulbosus Zheng & Zhong, 2001 , syn. nov.

= Exothotettix jiangxiensis Liang & Jia, 2008 , syn. nov. [ Liang, Jia, Shi, Wu & Chen, 2008 in OSF]

= Tetrix glochinota Zhao, Niu & Zheng, 2010 , syn. nov.

= Tetrix gibbosa Zheng & Zha, 2011

= Alulatettix nigromarginalis Zhang, Deng & Zha, 2014 , syn. nov.

= Alulatettix flavotibialis Zhang, Deng & Zha, 2014 , syn. nov.

Material examined. Our specimens. 64 males and 83 females, and 7 nymphs (2 males and 5 females), PR. China: Anhui (Jinzhai, Huoshan, Yuexi, Shitai, Huangshan), May–August 2010 –2021, coll. Wen-Jing Ding, Jian-Hua Ding, Xiao-Jie Zhang, Li-Bin Ma, and Ling-Sheng Zha (including the type specimens of Alulatettix nigromarginalis and Alulatettix flavotibialis ) . Two females, PR. China: Jiangxi (Lushan), 3 August 2021, coll. Wen-Jing Ding, Jian-Hua Ding and Ling-Sheng Zha.

Depositions in the Institute of Zoology, Shaanxi Normal University, Xi’an, PR China. Syntypes of Mishtshenkotetrix gibberosa : three females, Anhui (Huoshan), 31 August 1989 ; two females, Anhui (Jinzhai), 21 August 1989 . Holotype and paratypes of Alulatettix bulbosus : one male and three females, Hubei (Luotian), 8–14 June 1999 . Holotype and paratypes of Tetrix glochinota : three females, Henan (Tongbai), 17 July 2001 . Holotype of Tetrix gibbosa : male, Anhui (Huangshan), 20 May 2010 .

Taxonomic placement. The species possesses the typical characteristics of the subfamily Tetriginae , including: 1) filiform antennae; 2) elongate medial carina of vertex ( Lu & Zha, 2020); 3) medial ocellus is situated below the lower margin of eyes; 4) smooth body surface (without humps); 5) normal dorsal margins of fore and mid femora (without furrow); 6) lateral lobe of pronotum is close to the body.

The species should be placed in the genus Tetrix , and the reasons include: 1) head is not at all elevated, and lateral carinae are nearly as tall as medial carina of vertex (differing from elevated head with higher lateral carinae in Ergatettix Kirby , Euparatettix Hancock , Bannatettix Zheng , Lamellitettigodes Günther , and Paratettix Bolívar ; Lu & Zha, 2020); 2) vertex is not at all contracted forwards (differing from extremely contracted in Teredorus Hancock ); 3) in lateral view, frontal costa together with medial carina of vertex is moderately rounded (neither wholly arcuate in Coptotettix Bolívar and Hedotettix Bolívar , nor strongly projected forwards in Clinotettix Bey- Bienko); and 4) conspicuous tegminal sinus and ‘normal’ flying organs (unlike shallow to absent tegminal sinus with ‘abbreviated’ flying organs in Alulatettix Liang , Formosatettix Tinkham and their relatives, Zha et al., 2020; also see the discussion part at below).

Typical characteristics. As a member of Tetrix , the species can be easily recognized by its lamellate and strongly elevated pronotum (strongly arcuate in lateral view). Our collecting practices indicate that the species possesses the pleomorphism of hind wings and the hind pronotal process. Most individuals are brachypterous, their hind processes do not reach the apices of the hind femora, and their hind wings only slightly surpass the middle of the hind processes; only few are macropterous, their hind pronotal processes surpass the apices of the hind femora, and their hind wings surpass the apices of the hind femora much more ( Fig. 2 ).

Other characters can also help to separate the species from other members of the genus, including: medial carina of vertex straight (in lateral view), elongate, as tall as lateral carinae but a little lower than the tops of eyes; vertex relatively flattened, 1.5–1.9 times as wide as one eyes; anterior margin nearly straight, reaching or slightly surpassing the anterior margin of eyes; in lateral view, frontal costa together with medial carina rounded, facial carinae above superior ocelli slightly concave; scutellum between grooves equal to or narrower than the diameter of scapus; superior ocelli situated at the middle of inner margins of eyes; antenna 15–16-segmented (males 15, females 15–16), inserted between the lower margin of eyes, the longest segments 5.5–6 times as long as wide; anterior margin of pronotum obtusely angled; ventral margin of mid femur weakly undulated; lower margin of hind pronotal process straight, internal lateral carina nearly straight, the area between them very narrow; the first segment of hind tarsus about 1.5 times as long as the third, the first and second pulvilli short with sharp tips, the third pulvillus long with obtuse tip; upper valvae of female ovipositor stubby, about 2.6 times (excluding the stipe) as long as wide; nymphs similar to brachypterous adults.

Measurements (in mm). Length of body: male 7.3–11, female 10–14.5; length of pronotum: brachypterous male 6.5–8, macropterous male unknown, brachypterous female 7.5–9.5, macropterous female 10–12; length of hind femur: male 5–7, female 6–8; length of antennae: male 4–4.5, female 4.5–5.

Taxonomic revision and synonyms. Due to the taxonomic confusions of both flying organs and brachypterous and macropterous morphs, the species have been described into some different species. These species were all recorded from the same or adjacent regions ( Fig. 4 ). On the basis of: 1) the classification standard of flying organs of Tetrigidae ( Zha et al., 2016, 2017, 2020), 2) the intraspecific variation relationship of brachypterous and macropterous morphs ( Ding et al., 2021; Zha et al., 2021), and the evidences of morphology and geography, we give necessary taxonomic clarification for the species.

The species was originally described as Mishtshenkotetrix gibberosa with 15 females from Anhui (Huoshan, Jinzhai) and Hubei (Yingshan) (holotype: Huoshan; Wang & Zheng, 1993); then, Niu et al. (1994) described its male with 34 males from Henan (Xinyang). Zheng & Zhong (2001) described it as Alulatettix bulbosus , syn. nov. with one male and three females from Hubei (Luotian) (holotype: male). Liang et al. (2008) described it as Exothotettix jiangxiensis , syn. nov. with one male and one female from Jiangxi (Shangrao) (holotype: male). Zheng & Zha (2011) described it as Tetrix gibbosa with two males from Anhui (Huangshan). Zhang et al. (2014) described it as Alulatettix nigromarginalis , syn. nov. with three males and seven females from Anhui (Shitai, Huangshan) (holotype: female, Shitai), and Alulatettix flavotibialis , syn. nov. with 21 males and 37 females from Anhui (Yuexi, Jinzhai) (holotype: female, Yuexi).

These are all brachypterous morph of the species and have consistent morphology. Recently we collected and observed its macropterous morph in Huangshan, Anhui. Individuals of the two morphs live in the same habitats; they are morphologically consistent, except for the different lengths of both hind wings and hind pronotal processes. Our macropterous collections match the characters of Tetrix glochinota , syn. nov., which was described with three females from Henan (Tongbai; Zhao et al., 2010).

Based on the type specimens of Mishtshenkotetrix gibberosa and Tetrix gibbosa and his collections from Anhui (Huoshan, Jinzhai), Hubei (Yingshan), and Henan (Xinxian), Deng (2016) confirmed that the two species are conspecific. The author suggested synonymizing Tetrix gibbosa with Mishtshenkotetrix gibberosa (accepted by OSF), but he did not give convincing reason why the species should be placed in Tetrix (only based on presented but relatively small tegminal sinus, which is similarly presented in Alulatettix and Aalatettix ). Following the Code of Zoological Nomenclature (ICZN, 1999), we formally accept Tetrix gibberosa (Wang & Zheng) as the species’ name, and synonymize all its duplications listed above.

Biology and habits ( Fig. 3 ). Tetrix gibberosa live in humid and semi-humid subtropic forests (below 2000 m) with sandy soil and sparse shrubs, mainly the borders of streams. They feed on mosses and all sorts of humus. Macropterous individuals are sparse and often move among shrubs, while brachypterous ones are common and prefer to jump on the ground. The species may overwinter as adults, because the collections in May of each year are all adults. Under low temperatures, they bury themselves in sandy soil; when raining or at night, they commonly conceal their bodies in leaf litter or humus layer. Color and maculation vary with the environmental changes, and individuals in the humid environment are often covered with some mosses. They usually live with Formosatettix lushanensis Zheng & Yang , Tetrix japonica (Bolívar) , Bolivaritettix circinihumerus Zheng , Bolivaritettix lativertex (Brunner von Wattenwyl) , Teredorus spp. and etc.. Several milky nematodes had been found living within the body of its nymph, and this is the first report that nematodes can parasitize pygmy grasshoppers.

Known distribution ( Fig. 4 ). PR China (Anhui, Henan, Hubei, Jiangxi) [or: the Dabieshan Mountains, the Lushan Mountains, the Huangshan Mountains , and their adjacent area] .

Figures

FIGURE 1. Lateral views of brachypterous Tetrix gibberosa (Wang & Zheng). a) male; b) female. Scale bars 2 mm.

FIGURE 2. Female Tetrix gibberosa (Wang & Zheng). a) frontal view of head (brachypterous); b) dorsal view of body (brachypterous); c) lateral view of body (macropterous). Scale bars a=1 mm; b, c=2 mm.

FIGURE 3. Tetrix gibberosa (Wang & Zheng) alive from Huangshan (Tangkou) (a, b, d) and Shitai (Guniujiang) (c), Anhui Province, PR China.

FIGURE 4. Distribution of Tetrix gibberosa (Wang & Zheng). a) map of PR China on which the distribution (red) of the species is marked; b) known distribution records (red dots) of the species.