Hexacentrus unicolor Serville, 1831

Farooqi, Mohd Kaleemullah & Usmani, Mohd Kamil, 2018, A new species and a new record of genus Hexacentrus Serville, 1831 (Orthoptera: Tettigoniidae: Hexacentrinae) from India, Zootaxa 4526 (4), pp. 547-560 : 548-551

Hexacentrus unicolor Serville, 1831

( Fig. 1, 2 )

Hexacentrus unicolor Serville, 1831 . Ann. Sci. nat. 22(86):146 Hexacentrus plantaris Burmeister, 1838 . Burmeister, H. 1838. Handbuch der Entomologie 2 2(I–VIII):714. Syn. By Kirby, 1906. A Synonymic Catalogue of Orthoptera ( Orthoptera Saltatoria , Locustidae vel Acridiidae ) 2:288.

Redescription. Male: Body medium sized and slender. Antennae with alternate short dark bands apically. Fastigium of vertex triangular, narrow; laterally compressed with a median longitudinal sulcus; apex rounded in lateral view; base of fastigium 1.88 times as wide as scapus; fastigium of vertex separated from the fastigium of frons by a deep furrow. Eyes globular. Pronotum saddle-shaped, dorsal region longer than wide and expanded towards posterior region, slightly depressed behind first transverse sulcus; with three transverse sulci, second and third ones restricted to disc; anterior dorsal margin slightly concave, posterior margin broadly rounded with a slight median excision. An hour glass like band covers the whole pronotum; median carina faintly visible. Pronotal disk flat, expanded, broadly rounded and highly rugose on posterior region; lateral lobes of pronotum inclined; longer than high; humeral sinus absent. Prosternum armed with two long spines; mesosternum and metasternum armed with a pair of short, thick sternite. Thoracic auditory spiracle large, oval, slightly hidden under the lateral lobe of pronotum with a tubercle at mid- anterior edge. Tegmina (narrow in males) longer than hind wings. Tegmen reaching beyond the middle of hind tibia when straight; apex rounded. Stridulatory file with 46 teeth; moderately sulcate; teeth are almost of same length throughout the file except at distal end where it becomes narrow gradually, and abruptly narrow towards proximal end with few teeth. Legs: genicular lobes of fore femora armed with a single spine on inner side and unarmed on outer side; mid genicular lobe armed with a single spine on both inner and outer side; hind genicular lobe armed with bispinose on both side. Fore coxae armed with a forward outwardly projecting spine. All femora dorsally unarmed. Fore femora ventrally armed with 4 to 5 minute spines with small spines each on inner margin and outer margin. Mid femora ventrally armed with small spines on inner margin; 2–3 minute spines with more minute spines on outer margin. Hind femora ventrally armed with 7–8 medium spines each on inner margin and outer margin. Tympanum on fore tibiae bilaterally closed, tympanal slits facing dorsally with a small, elongated pit below it. Fore tibiae ventrally armed with 6 long, movable, outwardly bowed opposing spines decreasing in length from basally to apically each on inner margin and outer margin. Mid tibiae dorsally armed with 2 small spines each on inner margin and outer margin. Mid tibiae ventrally armed with 6 long, movable, outwardly bowed opposing spines decreasing in length from basally to apically each on inner and outer margin. Hind tibiae dorsally armed with 40–42 spines each on inner margin each on inner and outer margin. Hind tibiae ventrally armed with 10–12 spines increasing in length and density from basally to apically on inner margin, 12–14 spines increasing in length and density from basally to apically on outer margin. Single dorsal pair of spurs and two ventral pairs (inner small and outer large) of spurs present on the apical region of hind tibiae. Ninth tergite feebly excised. Tenth abdominal tergite with deep excision and. Supra-anal plate triangular with basal groove; as long as broad. Subgenital plate long with median longitudinal furrow apically, lateral ridges well developed, apical margin with rounded excision; styles diverging basally, apex slightly incurved. Cerci robust with a small tubercle on internal side, then abruptly narrowing to a long digitiform apical appendage with decurved apex.

Female: Tenth abdominal tergite with longitudinal median incision. Supra-anal plate triangular with dorsal groove, apex truncate; Paraprocts with triangular projection at apex. Subgenital plate basally broad, apex with weak median excision. Cerci conical, thick, apex with smooth conical appendage. Ovipositor broad at base; apex narrow; slightly upcurved.

Morphometry (length in mm)

Material Examined: India—Uttar Pradesh, Lucknow, Shahpur (29°21'0.41"N, 77°32'51.34"E), 4♂♂, 3♀♀, 05.X. 2014, on millet, (coll. M. K. Farooqi); Etawah, Peetambarpur (26°49'9.93"N, 79° 1'1.32"E), 1♂, 2♀♀, 07.IX.2015, on millet, (coll. M. K. Farooqi); Bijnor, Ram Bagh (29°22'23.63"N, 78° 7'25.37"E), 3♂♂, 5♀♀, 28.IX.2016, on millet, (coll. M. K. Farooqi); Moradabad, Mangupura (28°49'22.30"N, 78°42'18.47"E), 2♂♂, 1♀, 24.IX.2016, on millet, (coll. M. K. Farooqi); Mathura, Mayur Vihar (27°29'3.62"N, 77°40'39.10"E), 2♂♂, 1♀, 10.X. 2016, on Paddy, (coll. M. K. Farooqi); Aligarh, Medical colony (27°55'17.58"N, 78° 5'1.44"E), 2♂♂, 1♀, 13.XI.2017, on bushes, (coll. M. K. Farooqi).

Distribution: India—Andaman & Nicobar Island, Himachal Pradesh, Manipur, Mizoram, Nagaland, Sikkim and Uttar Pradesh.

Elsewhere: Borneo, Celebes, China, Japan, Java, Moluccas, Myanmar, Philippines, Sumatra, Singapore, Taiwan and Thailand.

Figures

FIGURE 2. Hexacentrus unicolor. (A–R): A—Lateral view of head and pronotum ♂, B—Lateral view of fastigium of vertex ♂, C—Dorsal view of pronotum ♂, D—Lateral view of sternum ♂, E—Dorsal view of left basal tegmen ♂, F—Dorsal view of right basal tegmen ♂, G—Stridulatory file ♂, H—Dorsal view of supra-anal plate ♂, I—Ventral view of subgenital plate ♂, J—Dorsal view of cercus ♂, K—Dorsal view of supra-anal plate ♀, L—Ventral view of subgenital plate ♀, M—Dorsal view of cercus ♀, N—Lateral view of ovipositor ♀, O—Dorsal view of fore tibia ♂, P—Dorsal view of left mid tibia ♂, Q—Dorsal view of right mid tibia ♂, R—Lateral view of hind tibia ♂.