Body size medium, 4 mm in length. Dense pappolepidia on venter. Elytral declivity in females with sutural tubercle; margin of ventrite 4 produced into a lamina, with deep median emargination (Fig. 102); margin of ventrite 5 with a broad horn on either side of the genital opening (Fig. 102).

Body length 3.67 mm to 4.22 mm (X‒ = 3.98 mm, s = 0.19, n = 8). Integument black. Dorsum densely covered with brownish black to dark greyish yellowish brown appressed scales; pale “V” on elytral declivity largely confined to summits of protuberances; other pale variegations usually present on elytra, not forming patterns. Scutellum densely covered with pale scales. Pronotum same colour as elytra; with striking, pale, posterolateral maculae corresponding to pale maculae on humeral angles, especially in females. Femora and tibiae with appressed scales dense, unicolorous, concolorous with elytral scales. Tarsi integument dark reddish orange to black. Rostrum. Length 0.77 mm to 1.04 mm (X‒ = 0.90 mm, s = 0.09, n = 7), width 0.52 mm to 0.66 mm (X‒ = 0.57 mm, s = 0.05, n = 7), length/width ratio 1.35 to 1.68 (X‒ = 1.57, s = 0.11, n = 7). Epifrons with appressed scales imbricate; setae dolabriform, decumbent, concolorous; median and lateral carinae not evident. Dorsal carina arched over antennal insertions. Lateral area ventral of antennal insertions with fine setae, without appressed scales. Antennae. Scapes in repose reaching hind margin of eyes; covered with appressed scales and setae. Funicular segments moderately articulated; segments 1 clavate, about 1.25 times longer than 2; segments 2 clavate, about 1.4 times longer than 3; segments 3 to 4 subspherical; segments 5 to 7 oblately spheroid, subequal in length. Pronotum. Length 1.06 mm to 1.24 mm (X‒ = 1.14 mm, s = 0.06, n = 7), width 1.61 mm to 2.16 mm (X‒ = 1.88 mm, s = 0.18, n = 7), length/width ratio 0.80 to 0.92 (X‒ = 0.86, s = 0.04, n = 7); in dorsal view widest in anterior 1/4, lateral margins strongly curved anteriorly, tapering posteriorly, more pronounced in females. Anterior margin slightly emarginate medially, posterior margin straight. Disc in dorsal view evenly curved; appressed scales imbricate; setae dolabriform, decumbent, dark to concolorous. Postocular lobes poorly developed. Elytra. Length 2.54 mm to 3.28 mm (X‒ = 2.78 mm, s = 0.25, n = 7), width 1.61 mm to 2.16 mm (X‒ = 1.88 mm, s = 0.18, n = 7), length/width ratio 1.39 to 1.58 (X‒ = 1.48, s = 0.07, n = 7). Anterior margin nearly straight, humeral angles rounded. Appressed scales tessellate to narrowly imbricate. Setae claviform, decumbent, pale to concolorous. Striae moderately impressed; interstriae flat on disc, convex on elytral declivity. Interstriae 1 at declivity flat in males, produced into a strong tubercle in females. Interstriae 3 and 5 at declivity swollen in both sexes. Apex in lateral view square in males; produced ventrad in females. Thoracic ventrites. Mesoventral process rounded. Metaventrite densely covered with pappolepidia. Abdomen. Ventrites clothed almost exclusively with pappolepidia, ventrites 1 and 2 moderately densely clothed, ventrites 3 to 5 increasingly sparse. Apex rounded. Males with ventrite 1 strongly depressed medially; ventrite 5 flat. Females with ventrite 1 flat; ventrite 4 with posterior margin produced into a subtriangular lamina with very deep apical emargination (Figs 102, 103); ventrite 5 disc with median furrow, posterior margin with narrow emargination with a horn either side of emargination. Male genitalia. Figs 50–53. Hemisternites with spiculum relictum slender. Penis with apex acute, ostial region thickened, forming a crest. Endophallus with gonoporial sclerite having pronounced anterior lobes, lacking posterior lobes. Temones 0.75 times as long as pedon. Female genitalia. Figs 54–57. Distal gonocoxites slender, 2.6 times longer than high. Bursa copulatrix long; not constricted anterior of proximal gonocoxite; sclerite horseshoe-shaped, long. Sternite 8 narrowly rounded at apex, membranous laterally. Everted ovipositor 2.14 mm in length, 0.57 times body length.

KX191344. 28S. KX191914. ArgK. KX191626. CAD. KX191085.

Holotype. Female (NZAC). Specimen mounted on card teardrop; abdomen removed, dissected and mounted in DMHF on white card below specimen; otherwise entire; elytra parted at apex. Labelled ‘NEW ZEALAND CO / Obelisk Range / Old Man Range / 14 Jan 2014/ SDJ Brown’ [printed, cream card], ‘On Phyllachne cushion / 1640 m / 45.3113°S 169.1956°E’ [printed, cream card], ‘Irenimus taxonomy / and systematics / SDJ Brown / PhD Thesis 2012–2015 / IRE4771’ [printed, cream card], ‘HOLOTYPE / Austromonticola / furcatus / Brown 2017’ [printed, red card]. Genomic DNA extract from enzyme digestion of abdomen: E196 (NZAC). CAD sequence KX191085; COI sequence KX191344; ArgK sequence KX191626; 28S sequence KX191914.

Paratypes. A total of 16 specimens (8 males, 8 females) designated as paratypes, bearing blue paratype label. Paratype specimens deposited in NHM, LUNZ, NZAC.

CO: Hyde Rock [45°23.358'S, 169°11.844'E, A], 15 Mar 1975, Watt JC, 1524 m, Litter (LUNZ: 1, NZAC: 1); Hyde Rock [45°23.358'S, 169°11.844'E, A], 22 Feb 1974, Dugdale JS, 1555-1616 m (NZAC: 1); Old Man Range [45°20.04'S, 169°12.534'E, A], 15 Mar 1975, May BM, 1524 m, Under Celmisia (NZAC: 1); Old Man Range [45°20.04'S, 169°12.534'E, A], 16 Jan 1965, Kuschel G, Townsend JI, 4500 feet, Celmisia prorepens (NHM: 1, NZAC: 4); Old Man Range [45°20.04'S, 169°12.534'E, A], 17 Jan 1965, Kuschel G, Townsend JI, 5000 feet (NHM: 1, NZAC: 1); Old Man Range [45°20.04'S, 169°12.534'E, A], 20 Feb 1974, Dugdale JS, 1615 m, Ex Celmisia haastii (NZAC: 1); Old Man Range [45°20.04'S, 169°12.534'E, A], 20 Feb 1974, Dugdale JS, 1615 m, ex Celmisia sessiflora (LUNZ: 1, NZAC: 1); The Herrons Station [45°24.739'S, 169°12.714'E, R], 17 Jan 2004, Emberson RM, Syrett P, 1590 m, Pitfall trap by tors in fell field (LUNZ: 1).

Fig. 116. South Island: CO: Old Man Range.

Label data: 1372 m to 1640 m (X‒ = 1509 m, s = 103, n = 16). Georeferenced data: 1583 m to 1665 m (X‒ = 1641 m, s = 19, n = 17).

From the Latin adjective furcatus, ‘divided, forked’, in reference to the form of the ventral lamina of the female; the name is an adjective.

Specimens have been collected in association with Phyllachne cushions and Celmisia daisies. In particular, the largest series was associated with C. prorepens Petrie, 1887, but specimens have also been found with C. haastii Hook.f., 1864, and C. sessiliflora Hook.f., 1864.