Aurum leonorensis Hutchinson and Moeseneder, 2019

Hutchinson, Paul M. & Moeseneder, Christian H., 2019, Aurum, a new monotypic genus of Cetoniinae (Coleoptera: Scarabaeidae) endemic to Western Australia, Australia, Zootaxa 4683 (2), pp. 277-285 : 280-282

Aurum leonorensis Hutchinson and Moeseneder , new species

( Figs 1 , 2 , 3 E–H)

http://zoobank.org/NomenclaturalActs/8d89eef8-b1fb-4012-8145-ff3e7d6259ec

Diaphonia species 2 Golding 2009, pp. 20, 22.

Material examined (10 specimens). Holotype, male ( Figs 1–2 ): AUSTRALIA: 15 km N of Leonora , Western Australia, 22.xii.1998, Golding and Powell, on Grevillea leaves, WAM : no identification number. Condition: undamaged. Paratypes, 9 males: AUSTRALIA. WESTERN AUSTRALIA : 2 ♂, 15 km N of Leonora , 22.xii.1998, Golding and Powell, on Grevillea leaves, WAM 8 specimens: without identification numbers, AFBRC 1 specimen: AFBRC8223-01 ; 5 ♂, 13 km N of Leonora , 22.xii.1998, Golding and Powell, on Grevillea leaves, P.M.H . 2 specimens: CET0335, CET0336, WAM 3 specimens: without identification numbers; 1 ♂, 45 km S of Leonora , 22.xii.1998, M. Golding, on Acacia leaves, P.M.H.: CET0337 ; 1 ♂, 10 km N of Leonora , 23.xii.1998, M. Powell, AFBRC: AFBRC8222-01 .

Description. Holotype. Male ( Figs 1–3 ). Length 19.3 mm, width 10.1 mm. Ovate depressed. Head ( Fig. 3E ). Black. Clypeus; clypeolateral ridge present, lateral margins linear, slightly divergent from antennal insertion, widest at midlength; apical angles broadly arcuate to slightly sinuate apex, lateral and apical declivity obsolete; disc flat, coarsely punctate, gradually inclined to moderately raised lateral and apical margins except for mid apex of clypeus where lateral ridges obsolete. Frons with coarse punctures with sparse erect setae basolaterally, ocular canthus nonsetose. Antenna; scape chestnut brown, bearing long, pale setae along dorsum of distal margin and short setal brush on posterior margin; pedicel chestnut brown; antennomeres 3–7 chestnut brown, bearing few short, pale setae; club chestnut brown, stout, equal to length of antennomeres 2–7, 0.4 x length of head; antennomere 8 with few stout setae medially on internal surface; antennomere 10 external surface apical third black. Thorax. Pronotum yellow, anterior and basal margin narrowly black, with inverted broad ‘Y’-shaped macula adjoining anterior margin and adjacent to basolateral margins, with black macula adjacent to lateral margin pre-midlength; basomedian margin slightly sinuate concave; basolateral margin linear, slightly angled anteriorly; basolateral angle obtuse; posterolateral margins linear subparallel, broadly arcuate midlength then linear attenuate to anterolateral angle; anterior margin linear; lateral margins bearing ridges; disc with coarse and few small punctures bearing few erect setae laterally. Scutellum yellow with lateral margins narrowly black, equilateral; few coarse punctures laterally in basal half, non-setose.

Elytron. Yellow; with black maculae on humeral and apical umbone, suture and elytral margins; broadly exposing mesepimeron; lateral margin with moderately pronounced humeral umbone; posthumeral arch arcuate, exposing metacoxa and sternites, narrowed apically and broadly arcuate to apex; disc rugulose; punctures in loose rows, bearing long, pale, erect setae; humeral and apical umbones moderately raised; costae indistinct, narrow; sutural costa narrow, elevated at apical declivity; apices spinose. Mesometasternal process present as short, parallel, apically arcuate structure ( Fig. 3A compared with Figs 3 B–D, declivous at anterior margin of mesocoxae, declivity quite vertical bearing tuft of yellow pilosity. Metasternum black, sparsely punctate medially, rugulose laterally, bearing long pilosity. Metepisternum black, rugulose bearing long, pale pilosity. Legs ( Figs 3 F–H). Femurs chestnut brown to black, protibia and protarsomere black; profemur dorsoventrally flattened, slightly attenuate to apex; ventral surface moderately rugulose, bearing long yellow pilosity. Protibia tridentate, equidistant acute denticles, second denticle pre-midlength; dorsal surface with coarse punctures in loose rows bearing erect, pale setae along internal margin but scattered and non-setose along exterior margin, setal brush sparse. Tarsomeres 1–5 longer than tibial length, bearing moderately long, yellow setae; claws long and simple. Mesofemur dorsoventrally flattened, parallel; ventral surface moderately rugulose, bearing very long, yellow pilosity. Mesotibia; ventral surface punctate in longitudinal rows coarser toward external margin, bearing sparse setae; internal margin and dorsal surface densely clothed with very long, yellow setae worn; external margin bidentate; medial and basal denticles acute; apically distinctly divergent; apex bispinose; spurs moderately short, fine, attenuate. Mesotarsomeres 1–5 longer than tibial length, bearing long, yellow setae, claws long and simple. Metafemur; dorsoventrally flattened; anterior margin arcuate; posterior margin sublinear; ventral surface sparsely punctate, rugulose along margins bearing very long, yellow pilosity. Metatibia; ventral surface bearing longitudinal rows of punctures tending coarse and rugulose along external margin bearing sparse setae; internal margin and dorsal surface densely clothed with very long, yellow setae worn; external margin bidentate, medial denticle forming a broad right-angle, basal denticle acute, apically distinctly divergent, apex sinuate; spurs long, fine, attenuate. Metatarsomeres 1–5 slightly shorter than tibial length, bearing long, yel low setae; claws long and simple. Metacoxa black, laterally yellow, posterolateral angle weakly obtusely angulate. Abdomen. Sternites black with anterior and posterior margins chestnut brown, laterally yellow; sternites 2–6 with shallow, wide depression; sternites 2–4 glabrous medially, punctate laterally bearing long, yellow pilosity; sternite 5 with single sparse row of punctures medially, punctures denser laterally bearing long, yellow pilosity; sternite 6 densely punctate with long, yellow pilosity. Pygidium yellow, apex dark brown-black, angulate through 90° (in lateral view) concentrically rugulose with centre in middle of disc, bearing sparse short pale setae on dorsal face, longer on ventral face. Genitalia ( Fig. 2 ). Phallobase broadest at apex, narrower near base of parameres, 2x length of parameres, dorsal groove narrow, ventral membrane bearing small ‘teardrop’-shaped sclerotised structure ( Fig. 2 , black arrow); parameres narrow, parallel, angulate pre-apex, apex truncate, apical surface punctate, dorsal cleft base broad, attenuate to apex.

Variation in paratypes. Aurum leonorensis is consistent morphologically, slight variation occurs in colour Lengths: 15.5–21.5 mm, widths: 8.4–11.0 mm. Head: clypeal apex linear; ocular canthi bearing few short setae; antennal scape and pedicel black. Pronotum: disc with macula ‘M’ shaped and may adjoin both anterior and basolateral margins, or neither; basomedian margin linear; scutellum with lateral punctures reaching apex. Elytron; humeral and apical umbones indistinctly raised; suture apex truncate. Metasternum black with yellow macula laterally. Legs: metatibia medial denticle acute. Metatarsomeres equal to tibial length. Pygidium with dark brown macula midlength adjacent to lateral margin.

Female. Unknown.

Etymology. The species name is derived from the town of Leonora, Western Australia, Australia, near where specimens were collected.

Discussion. Aurum leonorensis is known from a single series taken on two consecutive days late in December 1998 in an area from 15 km north to 45 km south of Leonora Western Australia ( Fig. 4 ). No other specimens were collected subsequently (despite an attempt by P.M.H. on 4 January 2014, approximately 45 km south of Leonora, where flowering Grevillea R.Br. ex Knight (Proteaceae) were encountered but only Metallesthes metallescens (White, 1859) and several Castiarina septemspilota (Carter, 1913) were observed on the flowers). One of the collectors of Aurum leonorensis noted that all specimens were found on “long, narrow leaved Grevillea (looks like Acacia ), leaves point upward” (M. Powell, personal communication 18 January 2018). Five species that occur in the area around Leonora may fit this description: Grevillea oligomera (McGill.) Olde & Marriott , G. nematophylla subsp. supraplana Makinson , G. berryana Ewart & Jean White , G. sarissa S. Moore subsp. sarissa , and Grevillea acacioides C.A. Gardner ex McGillivray. The image in Golding (2009) on page 22 (referred to as Diaphonia species 2), which shows an adult on bloom, is not indicative of the species occurring on this plant. It was placed on it for photographic effect only (M. Golding, personal communication). The photographed specimen was captured and is in the type series. The habitat of the species appears to be predominantly Acacia Mill. (Fabaceae) with intermittent Eucalyptus L’Hér. (Myrtaceae) and few Grevillea . Despite the lack of females, we assume that because of the short antennal club in males, the species belongs in the flower visiting and feeding group of Australian cetoniine genera ( Moeseneder & Hutchinson 2016) and that both sexes mate on the flowers. Based on our previous observations of Australian cetoniines, it is likely that external morphology and behaviour of both sexes are similar.

Figures

FIGURE 1. Aurum leonorensis holotype, male.

FIGURE 2. Aurum leonorensis holotype, male aedeagus. Black arrow indicates location of sclerotisation on phallobase.

FIGURE 3. Aurum leonorensis and comparison taxa selected characters. For descriptions of characters refer to Table 1. A, Aurum leonorensis schematic cap-shaped mesometasternal process; B, Aphanesthes and Diaphonia schematic fungiform mesometasternal process; C, Aphanesthes and Chondropyga schematic arrowhead-shaped mesometasternal process; D, Aphanesthes and Chondropyga schematic bud-shaped mesometasternal process; E, A. leonorensis head; F, A. leonorensis metaleg (setae on femur and tibia not shown); G, A. leonorensis mesoleg (setae on femur and tibia not shown); H, A. leonorensis proleg. Note: 5 mm scale applies to all leg drawings.

FIGURE 4. Aurum leonorensis collecting locations (red squares). Vegetation classes: yellow areas—deserts; green areasgrasslands; grey shading—ground elevations.