Paragavialidium Zheng

Ding, Jian-Hua, Wen, Ting-Chi, Wu, Xiao-Min, Boonmee, Saranyaphat, Eungwanichayapant, Prapassorn D. & Zha, Ling-Sheng, 2017, Species diversity of Tetrigidae (Orthoptera) in Guizhou, China with description of two new species, Journal of Natural History (J. Nat. Hist.) 51 (13 - 14), pp. 741-760 : 749-752

Paragavialidium Zheng

New record for Guizhou, China ( Zha et al. 2016d)

48. Paragavialidium prominemarginatus Zha & Ding sp. nov. *

( Figures 5 (a–b) and 6(a–f))

Female. Body size large. Head short, vertex slightly under level of pronotal disc, 2.5 times as wide as one eye, anterior margin undulate and depressed, anterior part of lateral carina not only folded upwards (nearly reaching top of eyes), but also protruding forward (not reaching anterior margin of eyes); medial carina visible in anterior half but absent in posterior half, paired fossulae distinct; in lateral view, anterior margin of vertex hidden behind eyes, vertex together with frontal costa nearly obtusely angled, fascial carinae not concave between lateral ocelli, then bowed and excessively protruding forward between antennal grooves; in frontal view fascial carinae diverged slightly above lateral ocelli, longitudinal furrow gradually enlarged downward, between antennal grooves 0.5 time as wide as diameter of scapus of antenna. Antennae filiform, 17- segmented, inserted far below lower margin of eyes; ninth segment longest, about 10 times as long as wide. Eyes globose and exserted, lateral ocellus situated slightly below lower margins of eyes ( Figure 6 (a–c)).

Pronotal disc broad, flat, and very coarse, with numerous humps. Anterior margin in dorsal view prominent forward and forming into a wide obtuse angle; median carina at the beginning erect, finger-like and obliquely forward; prozonal carinae erect and parallel, in lateral view undulate and a little surpassing anterior margin; extralateral carinae conspicuous, triangular and large, a little surpassing anterior margin; anterior margin both between median carina and prozonal carina, and between prozonal carina and extralateral carina with a small tooth, respectively ( Figure 6 (a, b)). Pronotum nearly cylindrical in prozona, median carina thick, in anterior part distinct, in posterior part barely visible; between sulci median carina elevated with swollen base, on both sides pronotum distinctly concave; behind humeral angles median carina also elevated, followed by concave pronotal disc in the centre but lateral margins strongly folded upwards; the posterior pronotal disc covered with numerous humps ( Figures 5 and 6 (a)). Humeral angles acute angled and with incomplete margins ( Figure 6 (a)), interhumeral carinae absent; hind process of pronotum long cone-shaped, reaching or slightly surpassing apex of hind tibia, apex truncate; pronotum 2.8–2.9 times as long as its posterior part (7.6–8.2 mm), which surpasses hind femur; posterior angles of lateral lobes of pronotum extending outwards, apex spine-like and slightly curved forward, posterior margin of each lateral lobe with two concavities. Visible part of tegmen long and ovate, slightly wider than mid femur, apex narrowly rounded; wings developed, almost reaching top of hind process. Upper and lower margins of fore and mid femora with three teeth, respectively, middle tooth of lower margin of fore femur small, distal teeth of mid femur also small; lower margins of fore and mid femur, and upper and lower margins of hind femur serrate; hind femur 3.6 times as long as wide, upper margin with three distinct large teeth, lower margin with six to eight small teeth ( Figure 6 (f)); antegenicular denticle long, apex right angled or obtuse, genicular denticle elongate and apex obtusely tapered; hind tibia slightly enlarging from base to terminal part, outer and inner sides with five to six spines each and with serrate margins; first segment of hind tarsus 1.15 times as long as third plus second segment, three pulvilli equal in length (one specimen) or third longer than first and second (three specimens), all apices obtuse; opposite side of first segment of hind tarsus slightly lamellate, margin serrate.

Ovipositor ( Figure 6 (d)): upper valva arcuate, about 3.3 times as long as wide; outer margins of upper and lower valvae with saw-like teeth, but base of upper valva smooth. Subgenital plate ( Figure 6 (d, e)): posterior margin three-toothed, middle tooth slightly folded inward and slightly longer than lateral teeth.

Body dark brown. Antennae black, the border between 3rd–12th segments yellow. Legs mainly black, all tibiae with three yellow rings each, basal and terminal rings of fore and mid tibiae small, basal and middle rings of hind tibia long; teeth on margins of all femora maculated with yellow. Hind wings dark blue, with metallic reflection.

Male. Unknown.

Measurements. Length of body (mm) ♀ 14.5–16.2 mm; length of pronotum ♀ 22–23; length of hind femur ♀ 9.1–9.6; length of antenna ♀ 7.5–7.9; width of pronotum between humeral angles ♀ 6.4–6.6.

Type material. Holotype: ♀, China, Guizhou, Jiangkou, Fanjingshan Mountain ( Figure 1 ), 27.872450 N, 108.784858 E, about 300 m altitude, 30 July 2016, collected by Lingsheng Zha. Paratypes: 2♀, same data as holotype.

Diagnosis. Currently the genus Paragavialidium consists of 12 species, but P. prominemarginatus sp. nov. can be easily separated from these congeners by obtusely angled anterior margin of pronotum ( Zha et al. 2016d). In contrast, the new species is most similar to P. sichuanensis Zheng, Wang & Shi ( Zheng et al. 2007) and P. islandium Zha & Wen ( Zha et al. 2016d), their main differences are shown in Table 1.

Etymology. The specific epithet prominemarginatus means anterior margin of pronotum of the new species is prominent forward.

Distribution. China (Guizhou), in Fanjingshan Mountain, Jiangkou County ( Figure 1 ).

Ecology and habits. Habitat of Paragavialidium prominemarginatus sp. nov. is humid, shady and stony, and has mountain springs and abundant mosses ( Figure 7 ). Their pronotal discs are dotted by some green mosses, and their body surfaces are covered tightly by numerous fine sands that cannot be washed off ( Figure 5 ). They feed on mosses and humus. Most of their life cycle may stay in sandy soil.

Figures

Figure 1. Geographical map of Guizhou Province, where localities of the described species in this study are showed.

Figure 5. Paragavialidium prominemarginatus sp. nov., female: (a) lateral view; (b) dorsal view. Scale bars = 5 mm.

Figure 6. Paragavialidium prominemarginatus sp. nov., female: (a) dorsal view of head and anterior pronotum; (b) lateral view of head; (c) frontal view of head; (d) lateral view of subgenital plate and ovipositor; (e) ventral view of subgenital plate and ovipositor; (f) left-lateral view of hind femur. Scale bars = 1 mm.

Figure 7. Habitat environment of Paragavialidium prominemarginatus sp. nov. Pictures were photographed by Lingsheng Zha in China, Guizhou, Jiangkou County, Fanjingshan Mountain.