Metallesthes unicolor ( Macleay, 1863 )

Moeseneder, Christian H., Hutchinson, Paul M. & Lambkin, Christine L., 2014, Revision of the genus Metallesthes Kraatz and description of Metallesthes anneliesae, a new species of Cetoniinae (Coleoptera: Scarabaeidae) from Queensland and New South Wales, Australia, Zootaxa 3881 (4), pp. 301-327 : 316-319

Metallesthes unicolor ( Macleay, 1863) revised status

( Figs 4 , 6 C–D, 7A–D, 7F, 7H, 7J, 7L, 7N, 7P)

Schizorhina unicolor Macleay, 1863: 15 .

Metallesthes (Schizorhina) unicolor . — Kraatz 1880: 203.

Metallesthes unicolor . — Masters 1886: 85; Allard 1995: 139; Calder 2002; Golding 2009: 36; Krajcik 2012: 159.

Material examined (197 specimens). Holotype, female ( Fig. 4 ): AUSTRALIA: King George Sound [Albany], W.A., ANIC 25 0 62403 [ ANIC]. Condition: Fair; right antennal club antennomeres 9 and 10 partially missing; all tarsomeres and claws missing on left proleg except tarsomere 1; metatarsomeres 4 and 5 and claws missing on right mesoleg, apical spurs on both protibia missing.

Other material (58 males and 138 females) AUSTRALIA. SOUTH AUSTRALIA: 4 f., Adelaide, [ NHML]; 1 m. / 1 f., Albert Hill, i.1921, P.W. Mellor [ SAM]; 3 m., Albert Hill, i.1923, P.W. Mellor [ SAM]; 1 m., Albert Hill, xii.1926, P.W. Mellor [ SAM]; 1 m. / 1 f., Cleve, ii.73 [ SAM]; 2 m., Darke Peak, P.G. Dolling [ SAM]; 1 f., Edithburg, 4.ii.91 [ SAM]; 1 f., Ferries McDonald C.P., i.1970, P. McQuillan [ SAM]; 1 f., Ferries McDonald C.P., 26.i.1978, E.G. Matthews [ SAM]; 1 f., Gawler, 28.i.86 [ SAM]; 1 m., Gawler [ NHML]; 1 m. / 1 f., Goolwa, 28.i.1886, A. King [ ANIC]; 1 f., Hartley, 9.iii.1948, D.C.S., 0 37627 [ WINC]; 10 f., Hartley, 18.ii.1950, D.C.S., 0 37617, 0 37618, 0 37619, 0 37620, 0 37621, 0 37622, 0 37623, 0 37624, 0 37625, 0 37626 [ WINC]; 1 f., Kimba, 11.i.1981, M. Powell [ WAM]; 1 f., Lyndoch [ SAM]; 1 f., Moonta Bay, 21.i.1984, C. van Dyke, CET 0629 [ PMH]; 1 f., Moonta Bay, 14.ii.1984, C. van Dyke, CET 0602 [ PMH]; 1 m. / 1 f., Moorkitabie, 15.ii.1989, K. Turner [ SAM]; 1 f., Murray River, H.S. Cope [ NHML]; 2 m., Overland Railway, 24 miles W of Kychering Soak, M. Chandler, COL 54651 [ NMV], K299067 [AM]; 2 m., Overland Railway, xi-xii.1908, M. Chandler, COL 54656, COL 54657 [ NMV]; 1 m., Overland railway, 24 miles W of Kychering Soak, 12.viii. -23.iii.1909, M. Chandler, 1971-567 [ NHML]; 1 m., Patessa [location not found], R.J. Burton [ SAM]; 1 m., Pinnaroo, 1.v.05, E.A. Fling [ SAM]; 1 m., Reevesby Island, i.1985, S. Parker [ SAM]; 1 f., Reevesby Island, 5.ii.1992, D. Armstrong [ SAM]; 1 f., Schlapes Gully, Adelaide, COL 54665 [ NMV]; 1 f., Scrubby Peak Lake, Eyre Peninsula, 4.i.2009, P. Hudson, dead on lake [ SAM]; 3 f., Scrubby Peak Lake, Eyre Peninsula, 26-29.vii.2009, P. Hudson, dead on lake [ SAM]; 2 f., Scrubby Peak Station, 21.x.2006, W.H.C. Moonaree [ SAM]; 1 f., Yorke Peninsula, Jung, COL 54639 [ NMV]; 2 f., Yorketown [ SAM]; 4 f., K299058 [AM], COL 54645 [ NMV], 69804, 69810 [QM]; 3 m., 1971-567 [ NHML]; 1 m. [ ANIC]; 2 m. / 3 f. [ SAM]. VICTORIA: 3 f., 21 km S of Bambill, ii.2004, S. Cowan & M. Moulds, K358840, K358843, K358844 [AM]; 2 f., S of 9 m square, Big Desert, 26.i.1971, G.W. Anderson [ ANIC]; 2 m. / 10 f., Big Desert, 2.ii.1990, A. Sundholm & J. Bugeja, K299176, K299178, K299164, K299167, K299168, K299169, K299170, K299171, K299173, K299174, K299175, K299177 [AM]; 6 f., Kiata, R. Oldfield, 69803, 69811 [QM], 0 37628, 0 37629, 0 37630, 0 37631 [ WINC]; 1 f., Kialla [assumed Kiata], iii.1917, R. Oldfield [QM]; 1 f., Kialla [assumed Kiata], i.1918, R. Oldfield [QM]; 2 f., Kiata, 2.ii.1919, R. Oldfield, COL 54640, COL 54653 [ NMV]; 1 f., Kiata, 20.ii.1919, R. Oldfield, COL 54660 [ NMV]; 2 m., Kiata, 20.xii.1959, G.R. Forbes [QM]; 1 m., Kiata, 13.i.1966, P.G. Kelly, COL 54662 [ NMV]; 1 m. / 1 f., Kiata, 7.ii.1970, S. Beattie, COL 54663, COL 54664 [ NMV]; 2 m., Up Knowing Track, Kulkyne N. P., 15.i.1999, J.& A. Skevington [QM]; 1 f., Mallee District, COL 54643 [ NMV]; 1 f., Mallee District, C. French, COL 54647 [ NMV]; 1 f., Mallee District, xi.1906, C.F. Junior, COL 54642 [ NMV]; 2 f., Winiam, iii.1917, R. Oldfield, COL 54641 [ NMV] [ ANIC]; 1 f., COL 54659 [ NMV]; 1 m. / 5 f. [ NHML]. NEW SOUTH WALES: 2 f., Eubalong West, 18.i.1995, CET 0595, CET 0597 [ PMH]; 3 m. / 7 f., Eubalong West, i.1996, CET 2014, CET 2015, CET 2016, CET 2017, CET 2018, CET 2019, CET 2020, CET 2021, CET 2022, CET 2023 [ PMH]; 1 f., Eubalong West, 18.i.1996, CET 0626 [ PMH]; 4 m. / 1 f., Eubalong, 18.i.1996, CET 0593, CET 0594, CET 0596, CET 0598, CET 0625 [ PMH]; 1 m. / 3 f., 8 km W of Eubalong, 27.i.2000, CET 0589, CET 0590, CET 0591, CET 0592 [ PMH]; 1 m., Round Hill Reserve, 23.i.1995, R. Mayo [ DAFWA]; 1 m. / 8 f., Round Hill District [ambiguous], 25.i.1990, A. Sundholm & J. Bugeja, K358853, K358826, K358827, K358828, K358830, K358829, K358831, K358832, K358833 [AM]; 1 m. / 1 f., Round Hill, 23.i.2000, R. Mayo, CET 0627, CET 0628 [ PMH]; 2 f., Roto, 9.i.1995, 60897-001, 60897-002 [ MIC]. WESTERN AUSTRALIA: 1 m. / 3 f., COL 54654, COL 54646, COL 54648, COL 54655 [ NMV]. QUEENSLAND: 1 f. [ NHML]. WITHOUT LOCATION: 1 f., Yandilla [ambiguous], F.A. Gore [QM]; 1 f., [location illegible], 0-046045 [ QDPC]; 1 m., 30.i.09 [ SAM]; 1 m., R. Patterson, CET 0601 [ PMH]; 2 m. / 3 f., COL 54658, COL 54661, COL 54644, COL 54650, COL 54666 [ NMV]; 3 m. / 19 f. [ NHML]; 2 m. [QM]; 1 m. / 1 f. [ SAM]; 2 m. [ WAM].

Diagnosis. Coarse pronotal and elytral punctation; unicoloured black base; mesometasternal process slightly divergent from body. Males without sclerotised area on phallobase ( Figs 6 C, 7H). Differences compared to M. metallescens : less setose; for remarks on colour see diagnosis of M. metallescens . Males with symmetric proclaws ( Fig. 7 J); females with pygidial pilosity restricted to basolateral regions and apex of elytra without pilosity or only with few setae ( Fig. 7 N). Similarities with M. metallescens : approximately same size. Differences compared to M. anneliesae: Larger ; posthumeral emargination not clearly and broadly exposing abdominal sternites laterally and apically ( Fig. 7 L); less pronounced costae; clypeal shape slightly attenuate and slightly elongate ( Fig. 7 P), in M. anneliesae quadrate.

Redescription. Holotype. Female ( Fig. 4 ). Length 19.7 mm, width 11.2 mm. Shiny black with very dark purple sheen, without metallic reflections. Head. Clypeus length:width ratio approximately 1.5:1; clypeolateral ridge linear attenuate to apex, moderately raised; lateral declivity distinct in dorsal view, widest at midlength; apical lobes acute, arcuate and with a distinct deep anteromedian emargination. Antenna with 10 antennomeres, club with 3 antennomeres. Club short, ovoid, length approximately same length as antennomeres 2–7; scape with posterior fringe and apical cincta of long, light red-brown setae; antennomeres 2–7 with several short, light redbrown setae. Clypeus and frons coarsely punctate often coalesced. Mentum with very long, light red-brown setae. Maxilla heavily setose. Thorax. Pronotum transverse trapezoidal, base trisinuate; basolateral angle acute, not produced; lateral margin sinuate concave-linear in basal half, narrowing to apex; lateral margin raised, narrow and indistinct on lateral portions of apical margin, obsolete across middle and basal margin. Surface evenly, coarsely punctate, often coalesced, each puncture bearing a short seta; midline impunctate in basal half and at apex. Scutellum slightly elongate, apex acute; bearing coarse punctures, sparse, long, light red-brown setae; midline impunctate. Elytron. Posthumeral emargination distinctly sinuate, exposing metacoxa; indistinctly bicostate (not counting sutural costa); sutural costa traceable to scutellum, edged with row of punctures in basal half, raised in apical half, tapering apically, non-spinose, bearing some elongate punctures, each bearing a long, light red-brown setae. First costae barely discernible, present only as glabrous, slightly raised impunctate interval; second costa barely discernible, slightly raised, undulating, traversing from humeral to apical umbones. Costal intervals coarsely irregularly punctate, often coalesced and in rows, becoming finer and denser in area of second costa, distal declivity and lateral declivity; punctures bearing long, light red-brown setae; area between suture and apical umbone with very few, short setae, distal declivity glabrous. Legs. Profemur expanded in basal half, dorsoventrally flat; ventral surface with punctures, bearing long, light red-brown setae. Protibia tridentate, basal interval smaller, apical denticle shortened due to wear; dorsal surface with several rows of punctures, rows closer to internal margin bearing short, pale setae. Ventral surface with distinctly raised inferior ridge, sharp apically, continuous with anterior margin of apical denticle; region adjacent to internal margin with row of coalesced punctures bearing few pale setae, external region rugulose and glabrous. Protarsomeres short, stout; tarsomeres 1–4 equal length; tarsomere 5 longer with sharp, convergent ventrodistal process; claws symmetric. Mesofemur subparallel, dorsoventrally flat; ventral surface with scattered punctures bearing long, pale setae. Mesotibia internal margin weakly concave-linear; external margin divergent, widest in basal third with 2 denticles then narrowed abruptly and parallel to apex, then divergent. Apex with 2 spines of equal length; interval deeply incurved; 2 longer apical spurs, moderately broad, with blunt apex, closely set, surpassing tibial apex and reaching midlength of tarsomere 2; ventral spur shorter; ventral surface with scattered micropunctures; dorsal surface bearing a row of very long, pale setae. Mesotarsi short, stout; tarsomeres 1–4 equal length; tarsomere 5 longest with few, stout bristles on apex of ventral surface of tarsomeres 2–5; tarsomere 5 with sharp, convergent ventrodistal process; claws symmetric. Metafemur posterior margin linear; anterior margin convex, widest medially, dorsoventrally flat, scattered punctures; a row of punctures adjacent to internal margin with scattered long, pale setae. Metatibia not compressed; internal margin sinuate towards apex; external margin linear, apically strongly divergent; a large denticle ending in transverse ridge at midlength; apically ending in a large spine on internal margin and broad truncate spine on external margin; 2 apical spurs, broad with rounded apex, closely set, surpassing tibial apex; dorsally slightly longer than ventral spur, curved, attaining midlength of tarsomere 3; ventral surface with a row of large punctures; dorsal surface medially and along external margin a row of long pale setae, internal margin with scattered setae. Metatarsi not elongate; tarsomeres 1–4 equal length; tarsomere 5 longest; several long bristles on apicoventral surface of tarsomeres 2–5; tarsomere 5 with sharp, convergent ventrodistal process, several bristles basally to projection; claws symmetric. Mesometasternum base broad, projection slightly laterally divergent; apex evenly arcuate, slightly produced medially; mesometasternal process reaching posterior of procoxae, in lateral view in same plane as metasternum, apically truncate prior to apical declivity; surface with few punctures bearing setae laterally; declivity bearing moderately dense, long, pale setae. Metasternum densely rugopunctate; clothed in long, pale setae laterally; denser laterally and basally, glabrous medially with micropunctures. Abdomen. Abdominal sternites 2–6 convex, broad median area glabrous and with few punctures; laterally more densely punctate and setose with long, pale setae; sternite 6 in entire apical half densely punctate and setose; sternite 7 with broad anteromedian depression, punctate except for narrow margin in basomedian area, less setose. Propygidium with some pale setae. Pygidium broadly depressed laterally, transverse; length:width ratio 1:1.7; concentrically rugulose around 2 points; glabrous except in small basolateral area that bears few, short, thin, pale setae. Male. Based on 9 specimens in the NHML collection. Length 14.5–19.9 mm, width 8.0– 11.4 mm. Differs from holotype in the following characters. Slightly smaller, narrower. Dorsally more setose, especially on pronotum. Pronotum less rounded. Area between suture and apical umbone and distal declivity bearing medium-length, pale setae. Legs: protibial denticles longer, thinner, sharper; intervals equal. Mesotibial external margin appearing serrate. Metatibia somewhat compressed, external margin with 1 or 2 small denticles, apex obliquely linear; 2 apical spurs, fine, acute, closely set, distinctly surpassing tibial apex; dorsal spur longer that ventral spur, attaining apex of tarsomere 2; dorsal surface medially punctate and with row of setae. Tarsomeres 1–4 equal length. Mesometasternal process somewhat divergent from body in lateral view. Abdomen: sternites 2–6 with broad, shallow, median impression; glabrous area narrower, sternite 7 anteromedian depression wider. Pygidium with long pilosity in basal half and short pilosity or glabrous in apical half; lateral depression less pronounced. Genitalia ( Fig. 6 C); parameres with ratio to phallobase approximately 1:2.5, with small basolateral projection; linear convergent from base to apical third, then slightly divergent, broadly arcuate to apex; area in apical corners less sclerotised, lighter; dorsal cleft narrow, parallel in basal 2/3 then attenuate to apex; phallobase (dorsal surface in situ) with medial, longitudinal impression.

Variation in specimens. Males. Length 15.1–20.0 mm, width 8.0– 11.8 mm. Females. Length 17.4–20.8 mm, width: 10.0– 11.5 mm.

Comments. Lea’s (1914) synonymy of M. unicolor with M. metallescens has been generally accepted ( Schenkling 1921, Calder 2002, Reid & Bulbert 2002). While several other authors continued to list M. unicolor as a separate species ( Matthews 1984, Allard 1995, Calder 2002, Golding 2009, Krajcik 2012), none formally raised M. unicolor from synonymy. Matthews (1984) wrote that M.E. Bacchus (NHML), in personal communication with him, considered M. unicolor to be a separate species and not synonymous with M. metallescens , but did not provide any other information.

Ecology. Tepper (1887) provided information on larvae and adults for the species he identified as M. metallescens but that is possibly M. unicolor since he specifically mentions the location Lyndoch, S.A., and Tepper usually studied South Australian beetles. He wrote that the larvae live in the base and roots of large, aged eucalypts, notably Eucalyptus camaldulensis Dehnhardt. Hence , the larval development of this species might take place in the same location in similar plants as that observed of M. metallescens . Tepper also noted adults feed on the flowers of Styphelia cordifolia (Lindley) Mueller in large numbers.

Figures

FIGURE 4. Metallesthes unicolor female holotype, 25 0 62403 (ANIC). Images by Tom Weir (ANIC).

FIGURE 6. Metallesthes parameres and mesometasternal process in several taxa. Metallesthes parameres. A – M. anneliesae, B – M. metallescens, C – M. unicolor. Lateral (left) and dorsal (right) views. Arrow indicates sclerotised area on phallobase of M. metallescens. Mesometasternal process. D – M. metallescens, Aphanesthes trapezifera and A. pullata, E – M. anneliesae and A. pullata, F – Tapinoschema digglesii, G – Diaphonia xanthopyga and A. succinea, H – Bisallardiana decorticata, I – Pseudoclithria maura and P. rugosa, J – P. ruficornis, K – Micropoecila cincta. Abbreviations: mc / f – mesocoxa and mesofemur, pc / f – procoxa and profemur.

FIGURE 7. Metallesthes diagnostic and sexual characters. A, B—sternital impression (A—males of all species; B—females of all species); C, D—metatibia apex (C—males of all species; D—females of all species); E, F—metatibia row of cilia (E—males of M. metallescens; F—males of M. anneliesae and M. unicolor); G, H—sclerotised patch on phallobase (G—males of M. metallescens; H—males of M. anneliesae and M. unicolor); I, J—proclaw symmetry (I—males of M. metallescens; J—both sexes of M. anneliesae and M. unicolor); K, L—dorsal visibility of sternites (K—both sexes of M. anneliesae; L—both sexes of M. metallescens and M. unicolor); M, N—apical pilosity (M—females of M. metallescens; N—females of M. unicolor); O, P—head shape (O—both sexes of M. anneliesae; P—both sexes of M. metallescens and M. unicolor). Grey shading and arrows emphasise diagnostic characters.