Melobasis confundo, Levey, 2023

Levey, Brian, 2023, A revision of the Australian species of the genus Melobasis Laporte & Gory 1837 (Coleoptera: Buprestidae), Part 3 (Revision of the azureipennis, cupricollis, iridicolor and melanura species groups), Zootaxa 5302 (1), pp. 1-100 : 70-72

M. confundo sp. n.

( Figs 111 , 124 , 137 , 160 )

Type locality: Queensland, McIlwraith Range .

Type specimens examined. Holotype ♀ ( QMA) McIlwrath Ra. [McIlwraith Range] 8 km NE Coen Qld. 13º53′30″S 143º15′2″E. 13 Jan. 1994. 540 m. G. and A. Daniels. R. Eastwood eucalypt forest/ UQIC donation 2011.

Diagnosis. Only ♀ known. General diagnosis: length 10.0 mm; head in upper two-thirds blackish olive, golden in lower third; antennae green; pronotum olive green with golden reflections; scutellum and elytra predominately blackish lilac with the bottoms of the punctures golden; underside brown bronze with blackish lilac reflections; legs predominantly brown bronze with greenish reflections, but all tarsi and anterior faces of fore tibia and fore femora green; underside laterally sparsely clothed with rather inconspicuous short silvery pubescence, prosternum, prosternal process, mesosternum, central parts of metaventrite and abdominal ventrites glabrous.

Head ( Fig. 124 ): very densely punctured with small, strong round and ovate punctures; moderately densely clothed with moderately long silvery pubescence; spaces between the punctures weakly microreticulate; clypeal excision broad, shallow, almost V-shaped, with a reticulate impunctate border; clypeal peaks obtusely angled; clypeal angles scarcely indicated; vertex slightly convex, slightly less than half width of head across eyes when viewed from above; eyes very strongly convex.

Antenna: segments 4–10 expanded, segment 4 with expansion triangular, segments 5–10 with expansion subquadrate, about two times as long as wide, slightly petiolate at base.

Pronotum: 1.73× as wide at base as long in midline; anterior margin moderately strongly bisinuate with a well developed median lobe, with a well developed entire beaded margin;

posterior margin strongly biarcuate; widest near basal quarter; lateral margins weakly diverging from basal angles to widest point, before almost rectilinearly converging to apical angles; basal angles slightly acute; as wide at base as elytra at base; lateral carina sharp very well defined, visible from above in basal half, very slightly curved, about two-thirds complete; punctation in central third very dense to contiguous, consisting of transversely elliptical punctures forming transverse series; punctation in lateral two-thirds very dense to contiguous, the punctures transversely oval and round; spaces between punctures weakly microreticulate; glabrous.

Scutellum: slightly elongate, shield shaped, about one-twentieth width of elytra at base; microreticulate.

Elytra: 2.20 × as long as wide at base; basal margin strongly biarcuate, moderately slightly widening from base over the humeral callosities thence slightly widening to midlength, before narrowing to the rather broadly rounded apices; lateral margins in apical half, and apices serrate, with rather large acute serrations, apical serrations much smaller close to the sutural margin; basal half of elytra posterior to humeral callosity also with slightly developed serrations; sutural margins very slightly raised in apical half, the subsutural depression scarcely indicated; without costae or costate intervals; punctation in inner half mostly sparse, consisting of small round punctures, with the punctures at the midlength lateral to the poorly defined subsutural depression, partly arranged in regular longitudinal series; punctation in outer half dense to very dense, consisting of slightly larger, mostly transversely ovate punctures, partly forming transverse series; weakly microreticulate between the punctures.

Hypomeron: contiguously punctate with large, very shallow, ovate punctures, the bottom of the punctures weakly microreticulate, with inconspicuous, silvery pubescence.

Prosternum: with a broad bead at the anterior margin; the anterior margin lower than the area behind; prosternal process moderately strongly widening distally, almost as wide as long at its widest point, densely punctate, with small round punctures, glabrous ( Fig. 160 ).

Mesanepisternum: densely punctate with small vermiform and round punctures, partly obscured by moderately strong microreticulation.

Central part of metaventrite, and inner quarter of metacoxa sparsely punctate with small, weak, mostly pin-prick punctures, lateral parts contiguously punctate, with fairly large shallow ovate punctures; abdominal ventrites, except for an impunctate basal band in the central three-quarters of each ventrite, contiguously punctate with small very elongate lunate punctures in central-third, laterally with larger partly coalescent lunate punctures, with moderately long, rather inconspicuous silvery pubescence.

Apical ventrite ( Fig. 137 ): contiguously punctate with elongate, lunate punctures over the whole surface, but not forming grooves parallel to the lateral margin; carinate in the midline in distal half; excision W shaped with a well developed flange, triangularly produced at centre; lateral spines well developed.

Fore tibia: slightly curved, with a setal brush on the anterior face, in the apical third.

Mid tibia: slightly curved, without teeth on the ventral face.

Ovipositor: moderately long, about three times as long as wide.

Comments. This very distinctive species is unlikely to be confused with any other described Australian species. It has an interesting combination of characters which confound some of the species group characterisations given in the species group key, given in the first part of this revision ( Levey, 2012). The carina in the midline of the apical ventrite suggest a relationship to the lauta species group of Queensland and N.W. Australia. On the other hand the very small scutellum, the rather broad prosternal process, and form of the excision of the apical ventrite indicate a relationship to the iridicolor species group, to which I tentatively assign it. Its definitive relationships will only become apparent once a male specimen is found.

Etymology. The species name comes from the latin confundo, to join together, to confuse, to throw into disorder, indicative of the uncertain species group relationships of this species.

Bionomics. Adult collected in January in eucalypt forest. Nothing else known.

Figures

FIGURES 111–114. dorsal habitus: 111. M. confundo sp. n. (holotype ♀); 112. M. aurocincta Carter (♀ Mourangee Station, Q. TMSHC); 113. M. imitator sp. n. (♀ paratype Port Peron, W.A. SAMA); 114. M. breviantennatus sp. n. (holotype ♀). Scale bars = 5.0 mm.

FIGURES 123–129. 123 dorsal habitus M. rufoviolacea sp. n. (holotype ♁). Scale bar = 5.0 mm. 124–129 head: 124. M. confundo sp. n. (holotype ♀); 125. M. aurocincta Carter (J 1.5 mls N.W. of Mourangee, Q. BLC); 126. M. imitator sp. n. (J Cape Naturaliste, W.A. TMSHC); 127. M. breviantennatus sp. n. (holotype ♀); 128. M. suturalis Thomson (J Hay Point, Mackay, Q. SAMA); 129. M. dentata sp. n. (holotype ♁). Scale bars = 1.0 mm.

FIGURES 136–142. 136 head M. rufoviolacea sp. n. (holotype ♁). 137–142 apical ventrite: 137. M. confundo sp. n. (holotype ♀); 138. M. aurocincta Carter (J 1.5 mls N.W. of Mourangee, Q. BLC); 139. M. aurocincta Carter (♀ Mourangee Station, Q. TMSHC); 140. M. imitator sp. n. (J Cape Naturaliste, W.A. TMSHC); 141. M. imitator sp. n. (♀ paratype Port Peron, W.A. SAMA); 142. M. breviantennatus sp. n. (holotype ♀). Scale bars = 1.0 mm.

FIGURES 159–165. 159. apical ventrite M. rufoviolacea sp. n. (holotype J) Scale bar = 1.0 mm. 160–161 prosternal process: Scale bars = 1.0 mm. 160. M. confundo sp. n. (holotype ♀); 161. M. rufoviolacea sp. n. (holotype ♁). 162–165 aedeagus & apex of parameres: 162–163. M. aurocincta Carter (J 1.5 mls N.W. of Mourangee, Q. BLC); 164–165. M. imitator sp. n. (Cape Naturaliste, W.A. TMSHC). Scale bars of aedeagus = 1.0 mm; scale bars for apex of parameres = 0.5 mm.