Figs 2A, 4A–C, 6A–B, 7A–B, 9A–C, 11G, 14A–E, 19A–D, 20A, Map 1(7).

Holotype (male): Papua New Guinea: Mt. Wilhelm, (5°48’S, 145°2’E), 14.x.1959, leg. J.H. Barrett —depository: Naturalis Biodiversity Center, Leiden (NBC).

Other specimens studied: Papua New Guinea: same data as holotype — 1 female, 1 male, paratypes, 1 female nymph last instar (NBC); Chimbu District, Mt. Wilhelm, Keglsugl, elev. 2460 m (5°48’S, 145°2’E), 25.viii.1974, leg. A.D. Hart— 1 female paratype (BPBM); Chimbu Province, Keglsugl, (5°50’S, 145°6’E), 12.v.1988, leg. J. van Stalle (St. 026, I.G. no. 27363)— 3 females, 1 male, paratypes (ISNB); Eastern Highlands, Aiyura, ex bush, (6°20’S 145°55’E), 27.v.1959, leg. J.H. Barrett— 1 female (NBC); Moife (15 km NW of Okapa), elev. 2100 m (6°38’S, 145°33’E), 7.–14.x.1959, leg. T.C. Maa— 15 females, 13 males, 1 nymph male (BPBM); Purosa (20–26 km SE of Okapa), elev. 1800–2020 m (6°43’S, 145°51’E), 17.–25.v.1966, leg. J.L. Gressitt & Tawi— 1 male (BPBM); Daulo District, Daulo Pass, elev. 2500 m (6°0’S, 145°13’E), 4.vii.1957, leg. D. Elmo Hardy— 1 male paratype (BPBM); New Guinea (NE), Chimbu Valley, elev. 1800 m (6°2’S, 144°57’E), 16.v.1963, leg. J. Sedlacek— 1 female (BPBM); New Guinea NE, Sinofi, 30 km south of Kainantu, elev. 1590 m (6°32’S, 145°58’E), 4.x.1959, leg. T.E. Maa— 1 female, 1 male (BPBM); Eastern Highlands, Mt. Wilhelm, Denquqo, elev. 2400 m (5°48’S, 145°2’E), 3.vii.1955, leg. J.L. Gressitt— 3 males (BPBM); Western Highlands, Keltiga, Mt. Hagen Valley, elev. 1700 m (5°52’S, 144°13’’E), 1–31.x.1961, leg. W.W. Brandt— 1 female, 1 male (NBC); New Guinea (NE), Ahl Valley, Nondugl, elev. 1750 m (5°52’S, 144°46’E), 8.vii.1955, leg. J.L. Gressitt— 1 male topotypic specimen (BPBM); New Guinea: Kenoa, 29.iii.1960 — 1 female (NBC); Papua, 1972, leg. Ströder— 1 female, 2 males, paratypes (NMW), note on locality: Although the labels of specimens collected by Karl Wilhelm Ströder read only “Neuguinea 73 Papua, Ströder leg.”, it is likely that the specimens had been collected in the environs of Goroka in 1973 where K.W. Ströder, a vendor of artefacts, did his ethnographic studies (Carlotta 2021, The British Museum 2021).

Diagnosis. H. bivittata sp. nov. is characterized by the pair of black lateral bands on the frons. A character that it shares only with H. dentata sp. nov., from which the new species can be easily separated by the shapes of the male cerci and the female subgenital plate. All other species studied have uniformly light faces except for the mandibles that can be black in several species. Other unique characters are the extended and lamellar, dorsal expansions and the shape of the internal projection of the male cerci. Highly characteristic is the complex modification of the male titillators in which the proximal and distal branches are connected by sub-membranous septa, which is found in a similar way only in H. wau sp. nov. Females also differ from most other species of the genus by the strong expansion of the dorsal ovipositor valves. A character that H. bivittata only shares with H. elevata sp. nov., from which it differs, apart from a shorter ovipositor (20–25 mm against 32 mm), by the strikingly different shape of the female subgenital plate that is elongate with very high but short baso-lateral expansions and the disc ends into long spine-like projections in H. bivittata, while in H. elevata it is nearly semi-circular in ventral view and elongate without expansion at base in lateral view (compare Figs 6A–B with 6J) and by the coloration of the striped face in H. bivittata that is of uniform color in H. elevata.

Description. Coloration of face pale with a pair of black lateral bands of variable width, rarely extended over the whole face (Figs 4A–C); antennal scrobae and fastigium frontis also black, median ocellus pale; mandibles often fully black. Femora with the following number of spines on ventral margins: (1) a 4–8, p 4–10; (2) a 4–8, p 2–5; (3) a 7–13, p 4–14 (n=38).

Male. Stridulatory file on underside of left tegmen 1.6–1.9 mm long (mean 1.7 mm) with 56–74 teeth (mean 65) that are at both ends very small, in central area rather wide: with 12–18 narrow basal (mean 14) teeth and 16–24 narrow apical (mean 19) teeth; in central 1 mm of file with 29–34 (mean 32) teeth [n = 12] (Figs 19A–D). Tenth abdominal tergite nearly domed but toward hind margin less strongly sloping than laterally, ventro-lateral margins concave; downcurved apical area deeply, roundly incised to almost dorsal surface and in ventral area slightly curved laterally and often little curved posteriorly above bases of cerci; the deep apical incision provides room for the large, triangular epiproct that has a deep furrow in midline (Figs 9A–B). Cerci moderately long, faintly curved mediad, and of subequal width to rounded tip; in apical area with a large, laterally compressed expansion with wavy margin that runs from top of cercus and there parallel to cercus axis and then curves ventrad and runs down along subapical internal surface of cercus to almost ventral margin; just below that expansion arises a long, dorso-ventrally compressed and in basal area little curved projection with converging lateral margins that divides before end into a short proximal cone with an acute spinule at tip and a longer, compressed and at base curved distal lobe with rounded tip that also carries an acute spinule at tip. Subgenital plate with basal margin strongly concave; basal area otherwise with upcurved and in ventral view bulging lateral margin; in central area with concave lateral margins and with a wide, obtuse medial furrow; in apical area divided into a pair of long, narrow, but in lateral view little elevated, lateral lobes that are more than half as long as the entire subgenital plate (13:20) and carry at tip short styli (Fig. 11G). In lateral view, subgenital plate regularly curved throughout behind basal widening; dorsal margin in basal area with an angle and parallel to dorsal margin with a deep furrow. Titillators very complex; in situ, as can be seen through the genital opening, they appear as a pair of rather soft dorso-ventral structures with furrowed central areas that carry two pairs of compressed apical projections from dorsal and from ventral margins: dorsal lobes with rounded apical margin and granular surface, also along margin, and ventral lobes with dentate margin (Figs 14A–B). In preparations the titillators appear as follows: in basal area, they are compressed and widened and run parallel to each other but are not fused; reaching the top, they are divided into proximal (anterior) and distal (posterior) branches; the proximal branches are short, dorso-ventrally compressed and moderately curved, the distal branches are elongate and little ascending posteriorly and end into a curved, obtuse tip, which re-curves and then runs ventrad where it ends into a short lobe at a level little above the level of the base of the titillators. The basal, dorsal and distal branches are connected by sub-membranous septa. In lateral view this structure thus appears as an irregular square with projections at all four angles. This square has an outer and an inner surface, is closed at bottom and probably filled with muscles in the alive insect. There is also a pair of large, elongate lateral sclerites with three flattened expansions from a little wavy central spindle; the membranes covering the titillators dorsally are provided with a pair of small rounded and convex semi-sclerotized caps (Figs 14C–E).

Female. Subgenital plate with ventral disc near base with diverging, afterward with converging lateral margins and terminating into a pair of elongate, spine-like, apical projections separated by a deep apical incision with rounded bottom; very basal area of disc on both sides merging into narrow dorso-lateral projections of about same length as disc including apical projections; they are separated from disc by a wide oblique furrow and afterward bulging with rounded tip (Figs 6A–B, 7A–B). Ovipositor only little longer than body, laterally compressed; behind basal constriction dorsal margin strongly elevated, highest in central third of its length, afterward gradually narrowing with dorsal margin straight or very faintly concave to rounded tip (Fig. 2A).

Measurements (25 males, 23 females).—Body w/wings: male 31–36, female 35–41; body w/o wings: male 22–29, female 20–29; pronotum: male 6.5–8.5, female 6.3–8.0; tegmen: male 21.5–30.0, female 26–30; hind femur: male 15.5–19.0, female 17.5–20.0; antenna: male 60–70, female 70–85; ovipositor length: female 20–25; ovipositor height: female 2.5–3.0 mm.