Melobasis rothei, Blackburn

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 : 38-40

M. rothei Blackburn

(Figs 5, 21, 41, 42, 64, 65)

Melobasis rothei Blackburn 1887:236 ; Kerremans 1892:106; 1903:160; Carter 1923:77; 1929:285; Obenberger 1930:434; Bellamy 2002:163; 2008:1332.

Type locality: S. Australia, near Sedan .

Type specimens examined. Holotype ♀ ( BMNH) 2208/ Type/ Blackburn Coll. 1910-236. [The original description says the specimen was collected near Sedan by Mr Röthe].

Other specimens examined. Western Australia: Beverley; Bullabulling; Canegrass Station ; Coolgardie, 14 km E.; Cue; Cue, Milly Soak; Kalgoorlie; Karonie; Meekatharra, 40 km W.; Meekatharra, 43 km W.; Menzies; Menzies, 41 km S.; Menzies, 65 km W.; Menzies, 40 km S.; Menzies, 60 km S.; Mount Magnet; 77 km E.S.E.Wurarga; Marloo Station; Youanmi; Youanmi, 35 km N.E. Northern Territory: Hermannsburg. South Australia: Kimba, 33.2 km E.N.E.; Ooldea; Quorn. New South Wales: Euston, 36.6 km E. on Sturt Highway. Queensland: no further data. Specimens in AMSA, ANIC, BLC, BMNH, CLBC, MPC, MVMA, NMPC, SAMA, TMSHC, WAMA.

Diagnosis. General diagnosis: length 7.7–12.5 mm; upperside predominantly greenish or brownish bronze; apices of elytra sometimes with a violet reflection, and more extensively elytra, lateral parts of pronotum and head with a slight reddish violet reflection; head in ♁ sometimes with a green reflection in part; underside predominantly dull reddish purple, often with a blue or green reflections in parts; underside sparsely to very sparsely clothed with short silvery pubescence in central parts, laterally moderately densely clothed with moderately long silvery pubescence.

Head (Fig. 21): ♁ very densely to contiguously punctate with small, moderately strong punctures, ♀ with punctures slightly weaker and slightly less dense; spaces between punctures weakly to moderately strongly microreticulate; sparsely to densely clothed with moderately long silvery pubescence; frontoclypeus broadly depressed at centre; clypeal excision a moderately broad, moderately deep U to V shape, between broad subtruncate to truncate lobes, the clypeal peaks scarcely developed, often rounded, the clypeal angles not developed; vertex flat, about half width of head across eyes when viewed from above; eyes strongly convex.

Antenna: not sexually dimorphic; segments 3 or 4–10 expanded, segment 3 or 4 subtriangularly expanded, segments 4 or 5–10 with expansion quadrate, slightly petiolate at base.

Pronotum: 1.45–1.60× as wide at base as long in midline; anterior margin weakly to moderately strongly bisinuate with a broad median lobe, which is variably developed, sometimes scarcely produced and truncate, with a well developed entire beaded margin; posterior margin weakly bisinuate; widest from basal third to midlength; lateral margins slightly rectilinearly widening from basal angles to midlength, sometimes with a slight sinuation just before the basal angle, weakly curvilinearly converging from widest point towards apical angles, before almost rectilinearly converging to apical angles in some specimens; basal angles right-angled; slightly narrower to as wide at base as elytra at base; lateral carina sharp well defined, slightly to strongly sinuate near base, about half to four-fifths complete; punctation in central sixth to fifth sparse to moderately dense consisting of small, round to slightly ovate punctures, sometimes with an incomplete to almost complete impunctate median line; punctation laterally dense, to contiguous near the lateral margin, consisting of larger punctures, which are mostly transversely ovate to transversely ellipsoidal nearer the centre, becoming ovate and round near the lateral margin; spaces between punctures weakly to moderately strongly microreticulate; with short to moderately long silvery pubescence close to the lateral margin and usually more extensively near the anterior angle.

Scutellum: as long as wide to moderately transverse, almost ovate to shield shaped, about one-sixteenth to one-fourteenth width of elytra at base; weakly to moderately strongly microreticulate.

Elytra: 2.24–2.50× as long as wide at base; basal margin very weakly to weakly bisinuate, slightly widening from base over the humeral callosities thence parallel sided to very slightly widening to midlength, before narrowing to the rounded apices; lateral margins in apical half and apices serrate, with acute serrations; sutural margins slightly raised in apical half; subsutural depression sparsely to moderately densely punctured with very small round and pin-prick punctures; punctation lateral to subsutural depression in inner half consisting of small mostly ovate punctures partly arranged in regular longitudinal series, without costae but interstriae sometimes slightly costate; punctation in lateral half very dense to contiguous consisting of slightly larger transversely ovate and ellipsoidal punctures, partly arranged in transverse series; weakly to moderately strongly microreticulate between the punctures.

Hypomeron: contiguously punctate with medium sized, very shallow, round and ovate punctures, the bottoms of which are weakly microreticulate, moderately densely clothed with long silvery pubescence.

Prosternum: with a moderately wide bead at the anterior margin; the anterior margin at about the same level as the area behind; glabrous or with very sparse silvery pubescence in central half, with moderately dense long silvery pubescence in lateral half; prosternal process strongly widening distally, less wide than long at its widest point, very sparsely punctate with tiny round and pin-prick punctures, glabrous or with scattered moderately long silvery pubescence.

Mesanepisternum: contiguously punctate, with moderately large very shallow variably shaped setae bearing punctures in anterior two-thirds, very densely punctate with smaller variably shaped punctures over the rest of the surface.

Central part of metaventrite and inner third of metacoxae, very sparsely punctate with tiny round punctures, glabrous or with scattered moderately long silvery pubescence; punctation of lateral parts composed of moderately large dense to contiguous semi-circular to lunate punctures, moderately densely clothed with moderately long silvery pubescence; abdominal ventrites glabrous, or with scattered short to moderately long silvery pubescence at centre, moderately densely clothed with moderately long silvery pubescence laterally; punctation sparse to moderately dense at centre, composed of very small lunate punctures, laterally with much larger, very dense to contiguous lunate punctures.

Apical ventrite (Figs 41, 42): lunate punctures coalescing but not forming well defined grooves parallel to the lateral margin; excision in ♁ broad, slightly W shaped, with a broad flange, slightly produced at the centre with well developed, moderately long, parallel lateral spines (Fig. 41); ♀ moderately broad, U shaped with a well developed flange and moderately long, divergent lateral spines (Fig. 42).

Fore tibia: ♁ & ♀ moderately strongly curved, with a setal brush in apical fifth on the anterior face.

Mid tibia: ♁ moderately strongly curved, moderately swollen, with a wide, deep, setae filled depression in central three-quarters, on the ventral face; ♀ slightly curved, without a depression.

Aedeagus (Figs 64, 65): parameres rather short and broad, apical part without spine like setae, with only long fine setae, abruptly narrowing in apical third; apex of median lobe narrowly truncate.

Ovipositor: not examined.

Comments. This species is unlikely to be confused with any other species in the group. The aedeagus is very different from any other known species. Externally the central depression of the frontoclypeus is not seen in any other species of the group.

Bionomics. Adults collected on leaves of Senna sp. , Acacia sp. Adults collected in January & February. Larval host unknown.