Irenimus aniptus Brown

Brown, Samuel D. J., 2017, A revision of the New Zealand weevil genus Irenimus Pascoe, 1876 (Coleoptera: Curculionidae: Entiminae), Zootaxa 4263 (1), pp. 1-42 : 10-13

1. Irenimus aniptus Brown , new species

Figures 1, 2 , 15, 16 , 41, 42, 43, 44, 45, 46 , 85

Diagnosis. Medium-sized species; oval; grey, often with encrustation of soil. Scape without appressed scales. Metaventrite laterally with appressed scales. Elytra with inconspicuous swelling on interstriae 3.

Appressed scales with coarse ridges, resulting in a duller appearance than I. crinitus n. sp.

Description. Body length 4.07 mm to 4.75 mm (X = ̄ 4.34 mm, s = 0.25, n = 5). Integument dark red to black. Dorsum densely covered with light greyish yellowish brown appressed scales with metallic reflections; elytral disc with small, scattered darker spots; inconspicuously paler on elytral declivity. Femora with proximal 2/3 dark greyish yellow, distal 1/3 and tibiae greyish yellow. Tarsi with integument strong orange yellow. Frequently with soil affixed to surface, obscuring vestiture. Rostrum. Length 0.88 mm to 0.96 mm (X = ̄ 0.93 mm, s = 0.04, n = 5), width 0.56 mm to 0.58 mm (X = ̄ 0.57 mm, s = 0.01, n = 5), length/width ratio 1.52 to 1.71 (X = ̄ 1.63, s = 0.08, n = 5). Epifrons with appressed scales overlapping; elongate scales setiform, semi-erect, dark; medial and lateral carinae barely evident. Dorsal carina arched over antennal insertions. Lateral area ventrally of antennal insertions with fine setae, without appressed scales. Antennae. Scape when in repose reaching hind margin of eye; covered exclusively with setae. Funicular segments loosely articulated; segment 1 clavate, around 1.3 times longer than segment 2; segments 2 to 5 clavate, getting progressively shorter; segment 6 subspherical; segment 7 oblately spheroid. Head. Eyes ovate. Pronotum. Length 1.25 mm to 1.45 mm (X = ̄ 1.36 mm, s = 0.09, n = 5), width 1.40 mm to 1.65 mm (X = ̄ 1.48 mm, s = 0.10, n = 5), length/width ratio 0.86 to 1.04 (X = ̄ 0.92, s = 0.08, n = 5); widest in anterior 1/3, lateral margins anteriorly abruptly curved to widest point, evenly curved behind. Anterior margin entire, posterior margin evenly curved. Disc topography evenly convex; appressed scales tessellate; elongate scales claviform, erect, mixture of pale and dark. Postocular lobes moderately developed. Anterior transverse groove weak beyond level with midpoint of eyes. Posterior transverse groove well-developed. Lateral posterior margin with inflection around 1/4 distance from top. Elytra. Length 2.60 mm to 3.20 mm (X = ̄ 2.83 mm, s = 0.24, n = 5), width 1.88 mm to 2.35 mm (X = ̄ 2.07 mm, s = 0.18, n = 5), length/width ratio 1.27 to 1.46 (X = ̄ 1.37, s = 0.07, n = 5). Anterior margin strongly curved posteriad, with humeral angles narrowly rounded. Appressed scales overlapping. Elongate scales setiform, semi-erect, dark on disc, pale laterally and posteriorly. Striae shallowly impressed; interstriae flat. Thoracic ventrites. Mesoventral process rounded. Metaventrite densely covered with overlapping appressed scales. Abdomen. Ventrites with inner vestiture composed almost exclusively of appressed scales, ventrites 1 and 2 densely clothed, ventrite 3 to 5 with posterior margins sparsely clothed. Apex broadly rounded. Males with ventrite 1 slightly depressed medially, ventrite 5 convex. Females with ventrite 1 flat; ventrite 5 convex, stronger than in male. Legs. Metatibiae with corbel present, narrow, bare; ventral margin of tibial apex slightly emarginate. Male genitalia. Figures 41, 42 . Penis with apex broadly rounded; dorsal plate not narrowed medially. Endophallus with large, lightly sclerotised plate proximal to aggonoporium; aggonoporial sclerite with short anterior lobes and broad posterior lobes. Female genitalia. Figures 43–46 . Sternite 8 with blade elongate. Styli elongate. Vagina not sclerotised. Bursa copulatrix long, sclerites absent. Spermatheca thick; ramus slightly produced, divergent from corpus. DNA Sequences: COI. KX191305 , KX191438 . 28S. KX191875 , KX192015 . ArgK. KX191588 , KX191722 . CAD. KX 191047 , KX 191167 .

Type material examined. Holotype. Male ( NZAC). Specimen mounted on card teardrop; abdomen removed, dissected and mounted in DMHF on white card below specimen; otherwise entire. Labelled ‘ NEW ZEALAND DN / Ardgowan Rd / Oamaru / 16 Sep 2012 / SDJ Brown’ [printed, cream card], ‘ Blower vac sample from / road verge / 45.0398°S 170.97968°E / SDJBcoll00011’ [printed, cream card], ‘ Irenimus taxonomy / and systematics / SDJ Brown / PhD Thesis 2012–2015 / IRE4881’ [printed, cream card], ‘ HOLOTYPE / Irenimus aniptus / Brown 2016’ [printed, red card]. Genomic DNA extract from enzyme digestion of abdomen: E306 ( NZAC) . CAD sequence KX 191167 ; COI sequence KX191438 ; ArgK sequence KX191722 ; 28S sequence KX192015 .

Paratypes. A total of 21 specimens (9 males, 7 females, 5 of undetermined gender) designated as paratypes, bearing blue paratype label. Paratype specimens deposited in BMNH, LUNZ, NZAC.

DN: Airedale [-45.0025, 170.9226, A], 2 Feb 1967, French RA, Soil (NZAC: 1); Ardgowan Road [-45.0398, 170.9797, R], 16 Sep 2012, Brown SDJ, Blower vac sample from road verge (LUNZ: 2); Ngapara [-44.9516, 170.7544, A], 25 Jan 1967, French RA, Soil (NZAC: 1); Oamaru [-45.0888, 170.9808, A], 11 Jan 1967, Ridell RJ, Ex bulk harvested grain (BMNH: 1, LUNZ: 1, NZAC: 1); Oamaru [-45.0888, 170.9808, A], 2 Dec 1964, Richards GJ, ex swede seedlings (NZAC: 2); Oamaru [-45.0888, 170.9808, A], 3 Dec 1964, Macann RJ, ex swede seedlings (BMNH: 1, LUNZ: 1, NZAC: 6); Oamaru [-45.0888, 170.9808, A], 5 Jan 1967, French RA, Soil/swedes (NZAC: 3); Weston [-45.0819, 170.9077, A], 19 Jan 1967, French RA, Soil (NZAC: 1).

Distribution. South Island:—/ DN /—( Figure 85 ).

DN: Ngapara; Oamaru.

Elevational range. Label data: no elevation data recorded. Georeferenced data: 7 m to 169 m (X = ̄ 39 m, s = 55, n = 22).

Etymology. Derived from the Greek aniptos meaning ‘unwashed’, referring to the frequent encrustation of dirt.

Biology. Many specimens were collected from swede ( Brassica napus napobrassica ) seedlings, but several were also found in soil, in harvested grain and through vacuum sampling of roadsides in farmland.

Figures

FIGURE 85. Distributions of Irenimus aniptus (circles), I. crinitus (squares), I. minimus (triangles) and I. stichus (stars).

FIGURES 1 – 8. Habitus photographs of Irenimus males. 1, 2: I. aniptus. 3, 4: I. crinitus. 5, 6: I. stichus, holotype. 7, 8: I. minimus. Scale bars = 1 mm.

FIGURES 15 – 22. Habitus photographs of Irenimus females. 15, 16: I. aniptus. 17, 18: I. crinitus. 19, 20: I. stichus. 21, 22: I. minimus. Scale bars = 1 mm.

FIGURES 41 – 46. Genitalia of Irenimus aniptus. 41, penis, dorsal view, al—anterior lobe of aggonoporial sclerite, dmsclerotised dorsal membrane, pl—posterior lobe of aggonoporial sclerite; 42, aedeagus, lateral view; 43, tergite 8, dorsal view; 44, ovipositor, dorsal view; 45, ovipositor and spermatheca, lateral view; 46, sternite 8, ventral view. Scale bars = 0.5 mm; 4 1, 42 at same scale; 43 – 46 at same scale.