Melobasis viridiceps, Saunders, 1876

Levey, Brian, 2018, A revision of the Australian species of the genus Melobasis Laporte & Gory 1837 (Coleoptera: Buprestidae), Part 2 (Revision of the nervosa species group), Zootaxa 4528 (1), pp. 1-79 : 48-49

M. viridiceps Saunders

(Figs 38, 65–66, 129–130, 163, 174, 187)

Melobasis viridiceps Saunders 1876:157 ; Kerremans 1885:137; Masters 1886:75; Kerremans 1892:107; 1903:160; Carter 1923:77; 1929:286; Obenberger 1930:436: Burns & Burns 1992: 24; Bellamy 2002:166. 2008:1336. Type locality: New South Wales.

Melobasis semistriata Blackburn 1887:235 ; Kerremans 1892:105; 1903:160; Carter 1923:81; 1929:285; Obenberger 1930:433; Bellamy 2002:159; 2008:1329. Stat. rev. (not syn. of M. prisca Erichson ). Type locality: South Australia? [the original description says there are two specimens “devoid of any record of capture”].

M. victoriae Obenberger 1942:102 ; Bellamy 2002:166; 2008:1336. Syn. nov. Type locality: Geelong, Victoria.

Type specimens examined. Melobasis viridiceps Saunders Holotype ♂ (BMNH) viridiceps E.S./ Saunders 74:18. Melobasis semistriata Blackburn Lectotype unsexed (SAMA) [here selected] Melobasis semistriata Blackb. Type [added later?]/ S. Australia / M. prisca Er. id by H.J. Carter. Melobasis victoriae Obenberger Lectotype ♂ (NMPC) [here selected] Geelong Vict., Austral. coll Ross, Berlin/ Typus/ Melobasis victoriae M. ♂ Type Det. Dr. Obenberger/ Mus. Nat. Pragae Inv. 22012/ my determination label.; Paralectotype ♀ (NMPC) same data as lectotype but Mus Nat. Pragae Inv. 22013.

Other specimens examined. South Australia: Flinders Chase, Cap de Covedic Rd.; Koala Park, Flinders Chase, Kangaroo Island. Victoria: Lakes Entrance; Melbourne; Mordialloc; Myrniong; Tallarook; Wangarabelle. New South Wales: Lambton. Specimens in AMSA, ANIC, BMNH, IRSNB, MVMA, QMA, SAMA, ZMC.

Diagnosis. General diagnosis: length 10.3–13.9 mm; specimens from S. Australia are brownish bronze to greenish bronze, except for the elytra and pronotum, which often have reddish purple reflections, and the ♂ which has the lower two-thirds of the head green, with coppery reflections; specimens from Victoria are usually green or coppery, sometimes the pronotum and elytra have reddish purple reflections.

Head (Fig. 163): very densely to contiguously punctate, with small round strong punctures in ♂, punctures slightly weaker in ♀, moderately densely clothed, with moderately long, silvery pubescence, which does not obscure the punctation; rims of the punctures shiny to weakly microreticulate in ♂, shiny in ♀; clypeal excision shallow to very shallow, U-shaped, with a narrow, impunctate, microreticulate border, sometime absent or only developed at the centre of the excision; clypeal peaks obtuse angled, usually without a defined clypeal angle; vertex flat, half width of head across eyes when viewed from above; eyes very strongly convex.

Antenna: segments expanded from 4–11, segment 4 with expansion triangular, segments 5–11 with expansion quadrate.

Pronotum: 1.45–1.61 × as wide at base as long in midline; anterior margin strongly bisinuate, with a very slightly developed, broad, median lobe; with a narrow well defined beaded margin; posterior margin weakly bisinuate; widest at mid-length; lateral margins slightly diverging from basal angles to widest point, often with a slight sinuation a short distance anterior to the basal angles, before converging to apical angles; basal angles acute; as wide as, or very slightly narrower at base, than elytra at base; lateral carina straight or slightly curved, about three-quarters to four-fifths complete; punctation in central-quarter of pronotum moderately dense to dense, consisting of small, mostly transversely elliptical punctures, lateral to this area the punctures become larger and more dense, progressively more ovate towards the lateral margin, where they are contiguous; sometimes with a narrow impunctate mid-line; with inconspicuous sparse short silvery pubescence close to the lateral margin, mainly confined to the apical third.

Scutellum: small, shield shaped or quadrate, about one-thirteenth to one-sixteenth width of elytra at base.

Elytra 2.36–2.52 × as long as wide at base; slightly widening from base over the humeral callosities, thence parallel sided, to slightly widening to mid-length, before narrowing to the sub-acute to acute apices; lateral margins in apical half and apices with moderately coarse, acute, serrations, the most apical serration much larger than those between it and the end of the suture; sutural margins slightly raised in apical half to two-thirds; punctation of subsutural depression sparse, consisting of tiny, round and pin-prick punctures; punctation lateral to the subsutural depression, in internal half, consisting mainly of tiny round punctures, mostly arranged in regular longitudinal series, the interstriae between being sub-costate; punctation in lateral half very dense, consisting of larger, mostly transversely ovate to elliptical punctures; weakly microreticulate.

Hypomeron: very densely to contiguously punctate, with large, very shallow, mostly ovate punctures, with sparse short silvery pubescence.

Prosternum: with a broad bead at the anterior margin; the anterior margin at the same level as the area behind; prosternal process slightly to moderately strongly widening distally, very sparsely punctate with pin-prick punctures, with a line of much larger punctures close to the lateral margin, glabrous (Fig. 187).

Mesanepisternum (Fig. 174): shiny, with none or a few large shallow setae bearing punctures.

Central part of metaventrite, inner part of metacoxa, central part of abdominal ventrites, glabrous or sparsely pubescent, more sparsely and weakly punctate than lateral parts of these structures, which are densely to very densely punctate, with lunate punctures, with sparse, moderately long, silvery pubescence.

Apical ventrite (Figs 129–130): lunate punctures not coalescing near the lateral margin, not forming grooves; excision in ♂ broad, shallow U-shaped, with a narrow flange slightly to moderately produced at the centre, with rather short, slightly divergent lateral spines (Fig. 129); ♀ narrow, U-shaped, with a slightly developed flange, the lateral spines short, slightly divergent (Fig. 130).

Fore tibia: slightly curved, with a slightly developed setal brush on the anterior face at the apex, in both sexes.

Mid tibia: ♂ slightly curved to almost straight, without teeth or other secondary sexual characters; ♀ straight.

Aedeagus (Figs 65–66): parameres gradually narrowing in apical third, the apical setae bearing part slightly widening in the mid-length, then very strongly narrowing to the apex; with a dense cluster of large, curved, spinelike setae, and the usual long fine setae restricted to the widened part; median lobe rounded at the apex.

Ovipositor: short about 2× as long as wide.

Comments. This very distinct species cannot be confused with any other in the group. The aedeagus is very different from that of all the other species. The line of larger punctures along the lateral margin of the prosternal process is not found in other species of the group.

Bionomics. Adults have been collected from October to December on Acacia spp. flowers. Larval host unknown.