Eugryllacris guomashan Ingrisch, 2018

Yin, Zi-Xu & Shen, Si-Zhong, 2021, New and little-known Eugryllacris from Yunnan, China (Orthoptera Gryllacrididae: Gryllacridinae), Zootaxa 5026 (4), pp. 541-554 : 547-550

publication ID	https://doi.org/ 10.11646/zootaxa.5026.4.5
publication LSID	lsid:zoobank.org:pub:D06D785A-9CC0-407A-B346-C22DADEB3DC8
persistent identifier	https://treatment.plazi.org/id/71298E4D-FFE4-FFBC-1198-D0ACCD5FF85A
treatment provided by	Plazi
scientific name	Eugryllacris guomashan Ingrisch, 2018
status

Treatment

Eugryllacris guomashan Ingrisch, 2018 View in CoL (过马NJÄffi⁂)

Material examined. 2♂ 1♀, China, Yunnan Province, Xishuangbanna Dai Autonomous Prefecture, Jinghong County, Jinuo Mountain (22°02’13”N, 101°00’13”E, Alt. 910), 10-IV-2020, coll. Chao-tai Wei GoogleMaps ; 1♂ 2♀, China, Yunnan Province, Xishuangbanna Dai Autonomous Prefecture, Mengla Town, Mengyuan Paradise (21°43’13”N, 101°23’10”E, Alt. 770), 25-II-2018, coll. Mansell Lin & Zi-xu Yin. GoogleMaps

Description. Large species. Fastigium verticis about twice as wide as scapus ( Fig. 5 View FIGURE 5 EHI; Fig. 6 View FIGURE 6 AB). Lateral ocelli tiny, two on each side, all similar in shape and size; median ocellus absent ( Fig. 5 View FIGURE 5 HI; Fig. 6A View FIGURE 6 ). Scapus elongate, shorter than the length of eyes; pedicel and first segment of flagellum combined about half length of eye ( Fig. 5H View FIGURE 5 ; Fig. 6A View FIGURE 6 ). Eyes elongate and oval, protruding outwards ( Fig. 5 View FIGURE 5 EHI; Fig. 6A View FIGURE 6 ). Face smooth; subocular furrows distinct ( Fig. 5 View FIGURE 5 HI; Fig. 6A View FIGURE 6 ). Anterior margin of pronotum projecting in the middle, posterior margin nearly straight; lateral lobes as long as deep, ventral margin nearly straight ( Fig. 5 View FIGURE 5 EFG; Fig. 6 View FIGURE 6 BC).

Tegmen surpassing hind knees ( Fig. 7 View FIGURE 7 CF). R releases RS at basal third, both branches forked near tip; MA fused with R in basal area; MP absent; CuA with a single branch that forks between basal third and mid-length into two veins, CuA1 and CuA2; CuP undivided, free throughout; with five Anal veins ( Fig. 6G View FIGURE 6 ).

Fore coxa with a spine at fore margin; fore and mid femora unarmed; fore tibiae ventrally with 5 pairs of large spines; mid tibiae ventrally with 5 pairs of spines, dorsally with an internal apical spur; hind femora ventrally with 6-8 external and 5-6 internal spinules; hind tibiae dorsally with 8-9 external and 6-8 internal spines, ventrally with a preapical spine and 2 apical spurs on both sides.

Male. Ninth abdominal tergite semi-globular, prolonged and downcurved, descending in posterior area furrowed in midline and before apex split granularly. Terminal of both splits contain a small disc with granular margin and below that disc with a fine styliform rounded projection, both projecting mediad. Subgenital plate about twice as wide as long, posterior margin wide and slightly obtuse-triangularly excised. Styli inserted laterally at posterior margin. ( Fig. 6 View FIGURE 6 DEF)

Female see Ingrisch (2018).

Coloration. General color green when alive; disc of pronotum unicolored. Face overall unicolored, green when alive; ocelli light yellow when alive; eyes bright yellow when alive; base area of mandible indigo in color when alive, transits into black in inner and tip area; clypeo-frontal suture teal in color; tegmen semi-transparent with green veins; cells of hind wings with large dark brown spots; abdomen greenish yellow when alive; hind femora and hind tibia spines green with black tips; all tarsus orangish yellow.

Drum. The adults make songs at night. Calling drums are made by male and female adults in a same frequency. The trills are made by using both hind legs to knock the plastic box at the same time. Calling drums are series of trills, the interval between trills are irregular. In this case, 5 series over 1 minute, varying from 3 to 6 trills/series (1 trill/second), 8 to 12 drums/trill (50 drums/second), at 23°C.

When adult male finds the adult female by flagellum, it will dance around female and makes sex clarification drums in response to female. Each drum is made by each hind leg to knock the plastic box once a time. Sex clarification drums consisted of short, rapid drums, the interval between drums are irregular. In this case, 60 drums in 20 seconds (3 drums/second), at 23°C.

Measurements (mm). Body (from head to tip of abdomen): 38.8–44.8; pronotum: 8.8–9.2; tegmen: 38.9–41.7; fore femur: 11.6–12.1; median femur: 10.9–11.4; hind femur: 18.5–18.9; fore tibia: 12.5–13.2; median tibia: 12.3– 12.7; hind tibia: 19.6–20.2; ovipositor: 14.3.

Natural history. E. guomashan is univoltine, reaches adulthood in around April to May according to field observation. Eggs become larger during hatching and eyes can be seen before hatchlings emerge ( Fig. 10M View FIGURE 10 ). Eggs undergo a hatching period about 40 days before hatchlings emerge in around June to August ( Fig. 10N View FIGURE 10 ). Highly predatory and invasive, senior individuals will inevitably consume junior ones when keeping together. E. guomashan is nocturnal, and individuals will hide into the shelter made of silk and leaves by themselves well before dawn ( Fig. 10 View FIGURE 10 FG). Nymphs molt once each three to four weeks, and junior nymphs molt inside the shelter while larger nymphs molt by hanging upside-down posture ( Fig. 10O View FIGURE 10 ; Data 1). Bodycolor will turn yellowish green from blueish green in premolt stage ( Fig. 10 View FIGURE 10 FG). Larger nymphs and adults show threat behavior when facing stimulus, with parts of the labrum hides under clypeus showing the jagged mandibles ( Fig. 5I View FIGURE 5 ; Data 2). During copulation, male E. guomashan produce a white sperm ampulla first ( Fig. 10I View FIGURE 10 ), and then a large translucent spermatophylax ( Fig. 10J View FIGURE 10 ); male E. guomashan grasps female’s ovipositor in a high frequency at the end of copulation (Data 2). Females eat the spermatophylax right after copulation (Data 2). Female adults were observed to make radial holes in wet phenolic floral foams ( Fig. 10L View FIGURE 10 ) and lay eggs into the holes in lab ( Fig. 10K View FIGURE 10 ).

Notes. E. guomashan is similar to E. serricauda . However, the projections on male ninth abdominal tergite more rounded than those of E. serricauda ( Fig. 6 View FIGURE 6 DEF). Posterior margin of female subgenital plate of E. serricauda ( Fig. 9C View FIGURE 9 ) is flatter than E. guomashan ( Fig. 6 View FIGURE 6 IJ). Ocelli of E. guomashan ( Fig. 5 View FIGURE 5 HI; Fig. 6A View FIGURE 6 ) are especially smaller than E. serricauda ( Fig. 9A View FIGURE 9 ). They can also be distinguished by the eyes color when alive: eyes of E. serricauda are red ( Dawwrueng et al. 2017, Fig. 9D View FIGURE 9 ; Ingrisch 2018, Fig. 100A), while eyes of E. guomashan are yellow ( Fig. 5 View FIGURE 5 ).