Austromonticola Brown

Brown, Samuel D. J., 2017, Austromonticola, a new genus of broad-nosed weevil (Coleoptera, Curculionidae, Entiminae) from montane areas of New Zealand, ZooKeys 707, pp. 73-130 : 77-79

Austromonticola Brown gen. n.

Type species.

Austromonticola mataura new species, here designated. Gender: masculine.

Diagnosis.

Integument densely covered with small, grey appressed scales, elongate setiform scales ('setae') conspicuous along elytral interstriae. Rostrum stout, in dorsal view about 1.5 times longer than wide; subparallel proximally; scrobes lateral; ventral curvature with head capsule approximately 90°. Pronotum in dorsal view evenly convex. Elytra with small, shallow punctures, interstriae flat. Metanepisternal sutures complete. Metatibiae with apex simple. Penis tubular. Bursa copulatrix with a single sclerite.

Differential diagnosis.

The combination of characters given above allows separation of Austromonticola from all other New Zealand weevils. The complete metanepisternal sutures distinguish them from Chalepistes Brown, 2017, in which the sutures are lacking. The abrupt 90° deflexion of the rostrum distinguish them from Catoptes Schönherr, 1842, which has a smoothly deflexed rostrum, angled about 120° with the ventral surface of the head capsule. The ridged appressed scales, conspicuous setae, evenly convex pronotum and small strial punctures separate Austromonticola from species of Inophloeus Pascoe, 1875 and Zenagraphus Broun, 1915, which have smooth appressed scales, inconspicuous setae, sculptured pronota and large, deep strial punctures. The subparallel rostrum and lateral scrobes, distinguish Austromonticola from Nicaeana Pascoe, 1877 and Haplolobus Broun, 1893, which have proximally widening rostra and dorsally situated scrobes.

Description.

Body length ranging from 3.4 mm to 8.9 mm. Densely covered with appressed scales on all surfaces, interspersed with elongate setiform scales ('setae'); appressed scales on dorsum oval, 35-55 μm long, ridges visible at 30 × magnification, generally coloured bluish grey, brownish grey or blackish grey, easily abraded. Rostrum. Subparallel proximally in dorsal view, widened at antennal insertions. Epistome punctate, plurisetose, slightly raised above frons but separation indistinct. Epifrons with longitudinal median carina, lacking sulci; continuous with occiput, without distinct dorsal separation between head capsule and rostrum. Antennae. Sockets dorsolateral, situated in apical 1/3 of rostrum. Scapes clavate, reaching posterior margin of eye in repose. Funicular segments clavate, subspherical or oblately spheroid, moderately to loosely articulated, segments 7 almost as wide as club. Clubs two times longer than wide, tapering apicad. Head capsule. Interocular width in dorsal view greater than width of rostrum at base. Eyes large, lateral, flat, ovate to subcircular with long axis vertical, parallel with sagittal axis. Ventral curvature of head capsule and rostrum in lateral view angulate, approximately 90°. Pronotum. Disc in dorsal view smooth, evenly convex. Postocular lobes poorly to well developed; fringed with numerous short vibrissae attaining a maximum length of 1/3 times anterior-posterior length of eye. Elytra. In dorsal view approximately parallel-sided in anterior 2/3. Setae arising from interstriae. Elytral declivity in lateral view rounded in males, but sutural margin at top of declivity developed into tubercles in females of several species. Interstriae 3 above the declivity slightly swollen in both sexes of most species, interstriae 5 above the declivity rarely swollen. Ventral margin in lateral view sinuous, highest point near level of metacoxae. Thorax. Procoxae contiguous. Prosternum visible behind procoxae as a raised tubercle ( “prosternellum”). Metaventrite with median suture visible only as a small, circular fovea posteriorly. Metanepisternal sutures complete. Abdomen. Ventrites 1 and 2 fused, subequal in length in middle; ventrites 3 and 4 subequal in length, approximately 0.5 times shorter than 1 or 2; ventrite 5 approximately equal in length to 1 or 2. Suture separating ventrites 1 and 2 curved anteriad in middle, other sutures straight. Wings. Absent. Legs. Uniformly and densely covered with appressed scales and setae, except for the posterior surface of the metafemora. Femora unarmed, maximum girth at about distal quarter. Pro- and mesotibiae with indistinct denticles along ventral margin and mucrones at apex; protibiae wider in distal 1/3 than proximal 1/3, incurved at apex. Metatibiae with dorsal and ventral margins subparallel; apical setal comb arcuate, pale; mucrones small, inconspicuous; without corbel. Tarsi with long, coarse setae on dorsal surface, without appressed scales; underside of segments 1 to 3 with short, dense setae forming pads medially divided by an inconspicuous glabrous line. Claws simple, separate, diverging. Male genitalia. Hemisternites 8 fully separate, with a forked membranous sclerite on the anterior margin of the membrane connecting them ('spiculum relictum’, Thompson 1992; Wanat 2007; Franz and Cardona-Duque 2013). Penis with pedon tubular, strongly curved, lateral lobes meeting or narrowly separated dorsally; temones shorter than pedon. Endophallus moderate in length, usually reaching anterior 1/3 of temones when in repose; armed with a variably-shaped sclerite surrounding the primary gonopore ('gonoporial sclerite'), other sclerites variably present. Tegmen with ring complete; parameroid lobes moderately developed, 0.35 times length of manubrium (Figs 85, 86); manubrium shorter than temones. Female genitalia. Sternite 8 with spiculum ventrale more than twice as long as blade. Gonocoxites divided into two parts; proximal part about 2.3 times longer than distal part, largely unsclerotised except for a strongly sclerotised rod; rods ventrally situated, broadening at proximal end; distal gonocoxite moderately sclerotised. Bursa copulatrix with a single sclerite.

Distribution.

Restricted to alpine regions in Otago and South Canterbury, New Zealand.

Etymology.

Derived from the Latin australis, meaning ‘southern’ and monticola, meaning 'mountain dweller’, alluding to the habitat of the species of this genus, being confined to the mountains of the southern part of the South Island. Gender masculine.

Biology.

Specimens of the genus have been collected in fellfield and cushionfield vegetation communities (Mark, 2012), commonly on top of, and close beside, cushion plants of the genera Phyllachne J. R. et G. Forst., 1776 ( Stylidiaceae ), Scleranthus L., 1753 ( Caryophyllaceae ), Veronica L., 1753 ( Plantaginaceae ), Hectorella Hook. f., 1864 ( Montiaceae ), Dracophyllum Labill., 1798 ( Ericaceae ) and Raoulia Hook. f., 1846 ( Asteraceae ), particularly when the plants have been in flower. Some species have also been found under specimens of Celmisia Cass., 1825 ( Asteraceae ) and Geum L., 1753 ( Rosaceae ). The larvae are as yet unknown.

Most specimens have been collected by hand collecting, though some have been captured in pitfall traps or by heat extraction from litter and turf samples.