Melobasis angustecostata subsp. angustecostata, Levey, 2018

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 : 7-10

M. angustecostata angustecostata ssp. n.

(Figs 20–22, 77–78, 124–125, 161)

Type locality: Western Australia, 11 km N. of Geraldton. Type specimens examined. Holotype ♂ ( ANIC), 11 km N.of Geraldton, WA. 23.ix.72, N. McFarland /

HOLOTYPE Melobasis angustecostata sp. n. B. Levey 2012. Paratypes as follows: 1♂ ( BMNH) Geraldton, W.A. H.W. Brown / 53 On Acacia , 12.10.1938. B.M. 1940-161 ; 1♂ ( ANIC) Geraldton, W.A. H.W. Brown / E.W. Ferguson Collection ; 1♀ ( SAMA) Geraldton, W.A. H.W. Brown ; 1♂ ( MVMA) Geraldton, W. Australia, J. Clark / F.E. Wilson Collection ; 1♂ ( ANIC) W. Australia, Geraldton , Clark 1911/ W.W. Froggatt Collection / 86 ; 1♀ ( UQA) Geraldton, W. Australia, J. Clark ; 2♀ ( IRSNB) Geraldton , Sept. 1926, H.J. Carter & J. Clark ; 1♂, 1♀ ( BLC) Geralton [Geraldton], 9/56 [ex. J.G. Brooks Coll.] ; 2♂, 1♀ ( WAMA) Geraldton , W.A. Sept.- Dec. 1916 -183 A, B & C/ M. lathami ; 1♂ ( WAMA) Geraldton / A54/72-631/ M. saundersi ; 1♀ ( WAMA) Geraldton , 27.9.56, F.H. Uther Baker ; 1♂ ( SAMA) Geraldton, Lea ; 1♀ ( SAMA) F.H. Uther Baker, Geraldton, W.A. 27.9.56 / [ex. S. Barker Coll.] ; 6♀ ( NMWC) W. AUSTRALIA: Coronation Beach, 25 km N. of Geraldton , 28?33′5″ 114?33′53″, 22.ix.2012. Flowering Acacia . B. Levey. NMW.Z. 2012.071 ; 1♂, 1♀ ( TMSHC) Coronation Beach, W.A. T.M.S., Hanlon , 21 Oct. 2007, on Acacia in dune ; 1♂ ( TMSHC) 12 km N. of Geraldton , W.A., T.M.S. Hanlon. On Acacia saligna leaves ; 2♂, 5♀ ( NMWC) W. AUSTRALIA: 7 km S. of Gregory, on Port Gregory Rd. , 28?12′24″ 114?19′40″, 22.ix.2012. On flowering Acacia / B. Levey. NMW.Z. 2012.071 ; 1♂, 1♀ ( BLC) same data as previous ; 2♂, 2♀ ( BLC) W.A. Drummond Cove, 7 mi. N. of Geraldton , 12 Oct. & 2 Nov. 73, Noel Mc Farland / on Acacia ligulata ; 3♂, 1♀ ( MPC) Wicherina Dam , W.A. 23/09/05, Acacia sp. leaves, M. Powell, D. Knowles ; 2♂, 3♀ ( BMNH) S.W. Australia, Yallingup, No. 1913 & 1–12 Dec. 1913, R.E. Turner, 1914-190 ; 1♀ ( WAMA) Yallingup , 45-822/ M. saundersi ; 5♀ ( BMNH) Nov Holl Occid , De Boulay, Fry Coll. 1905 100 ; 2♂, 2♀ ( SAMA) Karang Stn., Shark Bay , W.A. Acacia sp. 3.x.57 [ex. S. Barker coll.] ; 1♂ ( MPC) Shark Bay W.A., Sep. 8 1989, G. Harold ; 1♀ ( MVMA) Sharks Bay W.A .; 1♂ ( SAMA) Kalbarri , Western Australia, 23.ix.69, F.H. Uther Baker, [ex coll. S. Barker] ; 3♂, 5♀ ( WAMA) Kalbarri , W.A. 5–17.ix.1977 & 6–13.ix.1980, L.E. Koch ; 1♀ ( WADA) Murchison House Stn. W.A. Sept. 1948, C. Jenkins ; 1♂ ( WAMA) Bold Park, W. Australia , 8-18.x.1969 L.N. McKenna leg. / 72-428; 1♀ ( WAMA) Eneabba (29?49′ S 115?16′ E), W. Aust. Sept. 7.82, R.P. McMillan ; 1♀ ( MPC) Hamelin Stn. Hmstd., W.A., Sept. 29 1992, Acacia lvs., M. Golding & M. Powell ; 1♀ ( MPC) False Entrance , W.A., Sep. 12 1981, Acacia, M. Golding ; 1♂ ( MPC) 10 km E. False Entrance , W.A., Oct. 2 1988, Acacia lvs., D. Knowles ; 2♀ ( TMSHC) Irwin River mouth, Dongara , W.A., 1 Nov. 1999, D. Knowles, on leaves of Acacia rostellifera ; 1♂ ( CLBC) Cervantes, D. Knowles / 23:9.77/ 562 ; 1♂ ANIC) Kalbarri , W.A. 26 Sep. 1979, sweeping shrub behind beach ; 1♀ ( ANIC) 28.10S 114.16E, Hutt Lagoon, 3km N.E. of Port Gregory , W.A. 10-11 Sep. 1981 A.A. Calder / on Acacia .

Other specimens examined. The following specimens has been excluded from the type series. Many of the specimens exhibit subtle external differences, or come from areas far removed from the coastal areas of south west Australia where the type series of M. a. angustecostata comes from. Some may belong to other cryptic subspecies or species.

W. Australia: 1♂ (TMSHC) 5km W. of Spencers Brook , 24.12.1998, D. Knowles, on Acacia lasiocalyx leaves; 2♀ ( TMSHC) Marchagee Tk. 7.4 km W. of Midlands Rd., W.A. 21 Oct. 2007, T.M.S. Hanlon, on Acacia leaves ; 1♂ 6♀ ( TMSHC) same as above but 15.5 km W. of Midlands Rd .; 1♂ 2♀ ( TMSHC) 1.5 km W. of Hines Hill , W.A. 6 Oct. 2009, T.M.S. Hanlon, on flowering Acacia ; 1♂ ( TMSHC) Hines Hill , 20 Oct. 2005, T.M.S. Hanlon & M. Powell, on Acacia leaves ; 1♂ 3♀ ( TMSHC) Hynes [Hines] Hill, W.A. 1940 [ex H.W. Brown coll.] ; 1♀ ( MVMA) Kookynie, W.A .; 1♀ ( WAMA) Murchison R., Sept. 54, A. Douglas. 72-425 .

The following specimens from inland south west Australia have a slightly shorter and broader form then the type series (Fig. 21). 2♂, 9♀ (WAMA) Tammin, W.A., H.W. Brown, du Boulay Collection. Specimens dated 16.9.1937, 10.11.37. One specimen bears the label Melobasis eremophila Br. [manuscript name] on A. eremophila 16.9.1937; 1♂, 2♀ (TMSHC) 10.10.1937, on Acacia eremophila ; 7♂, 1♀ (TMSHC) 12.10. & 20.10.46, D.W.B., on Acacia eremophila [ex. H.W. Brown Coll.]; 1♀ (NMWC) W. Australia, Badjaling Nature Reserve, near Quairading, 31?59 ′117?30′, 4.x.2012, on flowering Acacia sp., B. Levey. NMW.Z. 2012.071; 1♂ (WAMA) Burracoppin, 50-5419/24; 1♀ (ANIC) Lake King, 10-11-1928, K. Carnaby. The aedeagus of a ♂ from Tammin agrees with that of specimens of the type series.

The following two specimens from inland south west Australia have a slightly more elongate form than the type series and the pronotum is considerably narrow than the elytra at the base (Fig. 22). The aedeagus of the ♂ agrees with that of specimens of the type series: 1♂, 1♀ (ANIC) Marloo Stn., Wurarga, W.A. 1931-1941, A. Goerling. A further 3♀ (WAMA) from Wurarga do not show these characteristics and are very similar to the type series.

Northern Territory: 1♀ ( TMSHC) 50 km N. of Erldunda, N.T., 18 Sep. 1988 , G. Marler; 1♀ ( SAMA) Coniston Station , near Alice Springs, M.W. Mules . South Australia: 1♀ ( MVMA) 20 m . N. of Cowell , S.A., 23.xi. 1973 , G.W. Anderson. Victoria: 1♀ ( MVMA) Kulkyne F., N.W. Vic., 24.10.66 , G.W.A.; 2♂ 3♀ ( MVMA, SAMA) Lake Hattah , J.E. Dixon Oct. & Nov. 1915 .

Diagnosis. General diagnosis: length 11.9–16.7 mm; head deep purple, blackish lilac to almost black; pronotum bronze to almost black, often with greenish reflections laterally, and coppery reflections centrally; elytra bronze with greenish reflections, the costae usually darker often partly reddish violet; underside bronze usually with extensive reddish purple reflections, sometimes blackish green laterally; underside laterally densely clothed with moderately long silvery pubescence, most of prosternum, prosternal process, mesosternum, and central parts of metaventrite and abdominal ventrites glabrous or very sparsely pubescent.

Head (Fig. 161): upper half of vertex densely punctate with strong small round and ovate punctures, punctures on lower half of head contiguous often coalescing to form elongate series with obvious shiny ridges between the punctures; densely clothed with long silvery pubescence; clypeal excision shallow U-shaped; impunctate clypeal border, broad; clypeal peaks right angled or obtuse angled, with a well defined clypeal angle; vertex flat, slightly more than half width of head across eyes when viewed from above; eyes very strongly convex.

Antenna: slightly sexually dimorphic; ♂ triangularly serrate from segment 4–10, the segments subequal, about twice as long as wide, slightly petiolate at base; ♀ weakly triangularly serrate from segment 4–10, segments 4–8 somewhat shorter, becoming slightly progressively shorter, segments 9–10 much shorter about as long as wide; segment 3 in both sexes, subcylindrical, slightly widening distally, about 2–3 × as long as wide at its widest point.

Pronotum: 1.38–1.50 × as wide at base as long in midline; anterior margin strongly bisinuate, with a well developed moderately broad median lobe, with a complete narrow beaded margin; posterior margin very weakly biarcuate; widest just in front of mid-length; lateral margins very slightly divergent from basal angles to widest point, before very weakly converging to apical angles; basal angles slightly acute or right angled; as wide or very slightly narrower at base than elytra at base; lateral carina slightly sinuate about half to three-quarters complete; punctation in central-quarter to central-third sparse, consisting of round, small, shallow, weak, and pin-prick punctures; sometimes with traces of a partly complete impunctate median line; punctation in lateral two-thirds to three-quarters dense consisting of larger, stronger slightly elliptical to round punctures; moderately densely clothed with moderately long silvery pubescence in lateral half, glabrous or more sparsely clothed with similar pubescence in central-half.

Scutellum: almost quadrate to slightly transverse, about one-eighteenth to one-fifteenth width of elytra at base.

Elytra 2.39–2.57 × as long as wide at base; basal margin very weakly biangulate; slightly widening from the base over the humeral callosities thence slightly widening to a little beyond mid-length, before narrowing to the rounded or slightly sub-acute apices; lateral margins in apical half and apices with moderately coarse acute serrations; sutural margins slightly raised in apical third, becoming costate nearer the base; each elytron with four approximately equidistant costae, the outermost two often very narrow and only slightly raised: 1st and 2 nd costae of about equal width, 1 st extending from base to about apical seventh; 2 nd costa slightly shorter but sometime almost fusing with 1 st apically; 3 rd costa extending from the humeral callosity to apical third; 4 th costa extending from humeral callosity almost to apex; the costae and raised sutural margin very sparsely punctate with very small weak and pin-prick punctures; subsutural depression densely punctate with small round to slightly transversely elliptical punctures; punctation of rest of elytra consisting of very slightly larger transversely elliptical punctures mostly coalescing to form transverse series lateral to the 3 rd costa; weakly microreticulate.

Hypomeron: contiguously punctate with shallow imbricate punctures partly obscured by dense long 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 widening distally, sparsely punctate with small weak round and pin-prick punctures, glabrous.

Mesanepisternum: contiguously punctate with small mostly round shallow punctures, partly obscured by dense long silvery pubescence, except for outer 5 th which is impunctate.

Central part of metaventrite, inner part of metacoxa, central part of abdominal ventrites glabrous, moderately densely punctate with small lunate punctures, lateral parts of these structures very densely to contiguously punctate with small lunate punctures, densely clothed with long silvery pubescence which partly obscures the punctation.

Apical ventrite (Figs 124–125): lunate punctures coalescing to form grooves parallel to the lateral margin, partly obscured by the pubescence; excision in ♂ broad, with a wide curved to truncate flange at the centre; lateral spines well developed, parallel (Fig. 124); ♀ narrow U-shaped, the lateral spines mor or less pincer shaped (Fig. 125).

Fore tibia: ♂ strongly curved, with a small triangular tooth at apex, and a well developed setal brush on the anterior face at the apex; ♀ tibia less curved, tooth absent and setal brush less developed.

Mid tibia: ♂ strongly curved with a small triangular tooth at apex; ♀ almost straight, without teeth.

Aedeagus (Figs 77–78): parameres slightly constricted behind the apical setae bearing part; apical setae bearing part narrow, strongly chitinised, with numerous fairly long slightly curved spine-like setae, in addition to the usual long fine setae; median lobe with a rounded tip.

Ovipositor: Elongate about 4 × as long a wide at widest point.

Comments. This species is most likely to be confused with M. planithorax sp. n. and M. latecostata sp. n. From the former species the male can be easily distinguished by the difference in the aedeagus (compare Figs 71 & 78), but also by the small triangular tooth at the apex of the fore tibia (large backwardly directed tooth in M. planithorax sp. n. (Fig. 208)) and the impunctate area at the outer fifth of the mesanepisternum (completely punctate in M. planithorax ). From M. latecostata sp. n. by the two previously mentioned characters, the slightly narrower 1st elytral costa, less dense pubescence of the underside and slightly more elongate form.

As mentioned under other specimens above, this species shows considerable external variation but the aedeagus of all dissected specimens except for those of M. angustecostata subacuta ssp. n. are the same as in the type series.

Etymology. The name comes from the relatively narrow 1st elytral costa in comparison to that of M. latecostata sp. n.

Bionomics. Adult collected in late September to December (mainly September and October) from Acacia species. Larval host unknown.