Pristoderus zigzag (Carter, 1939) comb. n.

(Figs 3i, 5i, 7i)

Tarphiomimus zig-zag Carter, 1939: 297 .

Types. Holotype: Australia, North Queensland, Mulgrave R. (NMV).

Other specimens examined. Queensland: 17.381S 145.788E, Mt. Bartle Frere, 1.6 km E Bobbin Bobbin Falls, 1053m, Pyrethrum, 18 Nov 0 9, G.B. Monteith & F. Turco, trees & logs, 18638 (1, QMBA ethanol coll.); 17.16S 145.53E, Bellenden Ker Range, 1 km S of Cable Tower 6, 500m, 17.x–5.xi.1981, EARTHWATCH/QLD MUSEUM, QM Berlesate no. 311, rainforest, stick brushings (1, QMBA); 17°16’S 145°49’E, 4 km W of Bellenden Ker, Massey Ra., 1250m, 10.x.1991, Pyrethrum, Monteith & Janetski (1, QMBA); Bloomfield tr Cape tribulation, 30 m, 14.vii.1982, rainforest log and bark litter, S & J Peck [Ga: 16.067S 145.150E] (1, ANIC); 17°13’S 145°25’E, 3 km W Bones Knob, 1100m, 10.xii.1995, Monteith, Cook & Thompson (2, QMBA); 15°57’S 145°08’E, Mt Boolbun South, 950m, 5.xi.1995, Monteith & Cook, pyrethrum – trees & logs (4, QMBA); 15°57’S 145°08’E, Mt Boolbun South, 850m, 5.xi.1995, Monteith & Cook, pyrethrum – logs (1, QMBA); Downey Creek, 25 km SE Millaa Millaa, 400m, 7.xii.1988, Monteith & Thompson [GE: 17.646S 145.800E] (1, QMBA); Mt Father Clancy, 9 km S. Millaa Millaa, 900–1000 m, 6.xii.1988, Pyrethrum / Logs & Trees, Monteith, Thompson [Ga: 17.583S 145.633E] (5, QMBA); Mt Father Clancy, 9 km S. Millaa Millaa, 900–1000 m, 6.xii.1988, Monteith, Thompson [Ga: 17.583S 145.633E] (2, QMBA); Mt Fisher, 7 km SW Millaa Millaa (Whiteing Rd), 1200 m, 5.v.1983, Pyrethrum knockdown, RF, G.B. Monteith & D.K. Yeates [GE: 17.568S 145.557E] (1, QMBA); 17°32’S 145°33’E, Mt Fisher (Kjellberg Rd), 1100m, 17.v.1995, G.B. Monteith, pyrethrum – logs only (6, QMBA); 17°33’S 145°33’E, Mt Fisher, ½ km NW, 8.ii. 1999, 1280m, G.B. Monteith, pyrethrum – trees & logs, rainforest, 2174 (1, QMBA); Gadgarra Rd. 5 km E Lake Eacham, 700m, 9.xii.1989, Monteith, Thompson & Janetski Pyrethrum / Logs & Trees, [GE: 17.284S 145.677E] (1, QMBA); 16°03’S 145°25’E, Mt Halcyon, 870m, 23.xi.1993, Monteith & Janetzki, pyrethrum/trees & logs (1, QMBA); Kirrama Range Douglas Ck Rd, 850m, 10-12.xii.1986, Pyrethrum knockdown, Monteith, Thompson & Hamlet [GE: 18.108S 145.710E] (1, QMBA); Kirrama State Forest, via Cardwell, 17-18.viii.1966, G. Monteith [Ga: 18.270S 146.018E] (1, UQIC); 16.536S 145.287E, Mt. Lewis Rd., 8.4 km NNW Julatten, 984m, Pyrethrum, 22 Nov 0 9, G.B. Monteith & F. Turco, trees & logs, 18634 (1, QMBA ethanol coll.); 16°30’S 145°16’E, Hilltop, 18 km N Mt Lewis, 1300m, 23.xi.1998, G. Monteith, pyrethrum trees, rainforest, 1941 (1, QMBA); Mossman Bluff Track, 5-10km W Mossman, 600m, 20.xii.1989 - 15.i.1990, Site 4 flt. intercept, Monteith, Thompson & ANZSES [GE: 16.459S 145.285E] (1, QMBA); Mossman Gorge, via Mossman, 9.viii.1966, Monteith [Ga: 16.466S 145.359E] (1, UQIC); Mulgrave River, Hacker [Ga: 17.233S 145.950E] (2, SAMA); upper Mulgrave River, 1-3.xii.1965, G. Monteith [Ga: 17.300S 145.800E] (4, UQIC); 17.580S 145.699E, Palmerston NP, Pyrethrum, 14 Jan 10, G.B. Monteith, 19546 (1, QMBA ethanol coll.); 16.534S 145.387E, Rex Range, 430m, Pyrethrum, 21 Sep 10, G.B. Monteith, rf, 34612 (1, QMBA ethanol coll.); 2 km SE Mt Spurgeon via Mt Carbine, 1100m, 20-21.xii.1988, Monteith & Thompson [GE: 16.213S 145.076E] (1, QMBA); Tully R. crossing 10 km S Koombooloomba Dam, 750m, 4.i.1990, Pyrethrum Logs, G.B. Monteith [GE: 17.957S 145.642E] (1, QMBA).

Victoria: VAUS Exp. Study, 37.23S 148.56E, Cobon North Coupe, 507.06 U/slope site, pitfall traps, 17– 25.iii.1992, R. Coy coll. (1, ANIC); Wilson’s Prom NP, Lilly Pilly Tr., 14.v.1978, S. & J. Peck, log litter and fungi [Ga: 39.021S 146.331E] (1, ANIC).

Notes to distribution and habitat occurrence. Specimen from “Wilson’s Prom” (Vic) has some distinctive morphological features, such as elytral hind angles less explanate and elytral apex more pointed and protruding.

Diagnosis. Pristoderus zigzag shares with P. tomentosus the zigzag crest along 3rd elytral interval, approximately even in lateral view and elytra slightly longer than their combined width. P. zigzag differs from P. tomentosus by pronotal process less prominent forward (not reaching the anterior margin of pronotum), strongly sloping posteriorly, the lateral pronotal notch deeper and semicircular, elytra with central and lateral portions darker.

Redescription. Body length: 5.2–7.9 mm.

Body convex, about 1.5–2 times as long as wide (ratio max length/max width: 1.68–1.76); colour light brown with darker patches on disc, sides and apex of elytra; vestiture of very short, dense, recumbent golden setae, holding a coat of dirt which forms a uniform encrustation.

Head transverse; eyes protruding lacking interfacetal setae; long, fine setae just posterior to eyes; supraorbital carina raised, indented with a distinct upwardly directed, pointed tubercle at posterior end, above the eye; supraantennal carina distinctly raised, frontal edge indented; antennal insertion frontal, just below the edge of supraantennal carina; antennae 11-segmented with a distinct 3-segmented club; antennomeres I and II subspherical, I larger than II; III narrow, distinctly longer than I and II; IV–VIII from subcylindrical to subspherical, gradually decreasing in length; IX–XI distinctly transverse to form a rather loose club.

Pronotum distinctly transverse (pronotal length/width: 0.61–0.64), as wide as elytra; dorsal median process anteriorly prominent but short, not reaching anterior pronotal angles, slightly sloping in lateral view with pointed tubercles on dorsal edge; antero-lateral margins widely lobate (5 lobes), expanded posteriorly to form a widely open lateral notch; two admedian upwardly pointed tubercles in middle.

Elytra about 1.1–1.2 times as long as wide (elytral length/width: 1.13–1.22), sinuate, with distinctly indented margins; strongly prominent tubercles along 3rd and 5th intervals; 3rd interval with tubercles variable in size and shape, joined to form a crest, strongly zigzag; proximal third of crest subparallel, ridge-shaped; apical tubercle distinctly raised, with edge entire; 5th interval with basal tubercle larger than others on same interval, with rounded edge.

Distribution and habitat occurrence. NE Queensland and SE Victoria (Fig. 15c); mostly upland tropical rainforest with some records from lowland tropical rainforest.

Two specimens have been collected in Victoria in two separate events in recent years (1978 and 1992) whereas the other available specimens are from the Wet Tropics. The specimen from Wilson’s Promontory NP has also been compared with the holotype by one of the authors (AS). This disjunct distribution may be due to mislabeling of the two specimens from Victoria or it may indicate that this species is more widespread from North Queensland to Eastern Victoria, even though rainforest habitats in SE Queensland and in New South Wales has been extensively sampled.