Melobasis septemplagiata, Carter

Levey, Brian, 2012, 3464, Zootaxa 3464, pp. 1-107 : 51-53

M. septemplagiata Carter

(Figs. 107, 172)

Melobasis septemplagiata Carter 1923:91 ; 1929:285; Obenberger 1930:434; Bellamy 2002:163; 2008:1332. Type locality: Western Australia, Cue.

Type specimens examined. Lectotype ♂, (here designated) ( SAMA), Cue, W.A. H.W. Brown, Co-Type H.J.C., Melobasis septem-plagiata Carter Id. by H.J. Carter, LECTOTYPE, Melobasis septemplagiata Carter, B. Levey det. Paralectotype ♂ ( SAMA), mounted to left of Lectotype on same card. Carter in his original description mentions eight specimens from Cue, and says the types are in the Australian Museum. I have only found four specimens from Cue and have therefore based my Lectotype designation on the two labelled cotype. The other two specimens from Cue in ( WAMA) are without original determination labels and these are not conspecific with the Lectotype designated above but are specimens of M. brittoni sp. n. There are six specimens labelled as cotypes from Ankertell, H.W. Brown in ( AMSA), ( SAMA), ( ANIC) and ( MVMA). The specimens from ( SAMA) are not M. septemplagiata but are specimens of M. brittoni sp. n. It is possible that Carter may have had these specimens before him when he did the description and incorrectly reported all the specimens as coming from Cue but it seems more likely that Carter labelled specimens he saw at a later date as cotypes.

Other material examined. Western Australia: Ankertell; 35 kms N. of Paynes Find; 6 mls S.W. of Paynes Find; Tammin; Marloo Stn., Wurarga. Specimens examined from ANIC, IRSNB, MPC, NMWC, SAMA, WAMA. Adults collected in October.

Diagnosis. General diagnosis: length 9.0– 12.9 mm; head and pronotum brownish-bronze, reddish-violet or violet-blue; elytra yellowish- or brownish-bronze, with the apices more or less suffused with reddish-violet, rarely with one or all of the following silvery-blue markings: a sutural vitta in the basal quarter; a humeral vitta of the same length, which extends along the basal margin to the lateral edge and onto the epipleura up to the level of the hind coxa; also sometimes extending on to the lateral margin next to the humeral callosity; a slightly sinuate median transverse fascia; a roughly obovate pre-apical macula; underside brownish-bronze or reddish-purple; lateral parts of underside densely clothed with long silvery pubescence.

Head: upper third of vertex moderately densely to densely punctured with small to fairly large round punctures; remainder of head very densely punctured with ovate punctures which largely coalesce to form linear series orientated dorso-ventrally on the lower half of the vertex and the frontoclypeus; densely clothed with moderately long to long silvery pubescence; unpunctured areas shiny to weakly microreticulate; clypeal excision fairly shallow to moderately deep, U-shaped, with an unpunctured weakly to strongly microreticulate border; clypeal peaks slightly acute to right angled; vertex flat, about three-fifths the width of head across eyes when viewed from above; eyes weakly to strongly convex.

Antenna: serrate from segment 4–10, the segments becoming progressively smaller and slightly less elongate, the expanded part of each segment more or less quadrate in ♂, that of segment 4 and sometimes 5 more or less triangular in ♀, the rest slightly quadrate.

Pronotum: 1.44–1.59 times as wide at base as long in midline; anterior margin strongly bisinuate, usually with a slightly developed broad median lobe, but sometimes the lobe is scarcely produced and the margin is almost straight at the centre; posterior margin bisinuate; widest at or near mid-length and often about as wide at posterior angles; lateral margins almost parallel or very slightly divergent to widest point, thence slightly to moderately strongly curvilinearly converging to the anterior angles; as wide as or very slightly narrower at base than elytra at base; lateral carina slightly sinuate, about half to three-quarters complete; punctation moderately dense in central fifth, consisting of small round punctures, which become progressively larger and denser towards the lateral margin; usually with at least a partly developed unpunctured midline; shiny or with weak reticulate microsculpture; moderately densely to densely clothed with long silvery pubescence in lateral half.

Scutellum: quadrate to slightly elongate; weakly microsculptured; about one-eleventh to one-thirteenth width of elytra at base.

Elytra: 2.36–2.66 times as long as wide at the base; basal margin strongly biangulate; slightly widening from base over the humeral callosities; thence almost parallel sided to the mid-length, before narrowing to the slightly attenuated rounded apices; lateral margins from just beyond mid-length and apices with moderately coarse acute serrations, usually with a distinct sinuation near the apex; sutural margin strongly raised in posterior half; inner half external to the subsutural depression sometimes with one or two slightly indicated costate intervals, but often only the one next to the subsutural depression discernible; subsutural depression sparsely punctured with very small round punctures; punctation lateral to the first costate interval consisting of larger denser punctures which become progressively denser larger and more ovate towards the lateral margin, where they form short transverse series; moderately strongly microreticulate.

Proepisternum: very densely to contiguously punctured with moderately large, shallow, ovate and round punctures, partly obscured by dense long silvery pubescence.

Prosternum: with a bead at the anterior margin which is sometimes poorly defined at the centre, at almost the same level as the area behind; lateral part of prosternum sometimes strongly depressed in front of the pleurosternal suture; prosternal process slightly widening distally, sparsely punctured with small round or pin-prick punctures, with a line of larger punctures near the lateral margin which sometimes coalesce to form a groove; glabrous.

Mesoepisternum: densely punctured, with large, shallow, round and ovate punctures; partly obscured by long silvery pubescence.

Apical sternite: similar in form to that of M. brittoni sp. n. ( Fig. 203); the lunate punctures coalescent near the lateral margin, sometimes forming weak ridges parallel to the lateral margin; excision fairly deep, the lateral spines moderately developed, but not as long as depth of flange, about one and half to two and half times as wide as deep; distal margin of flange straight.

Tarsal claws: slightly widened at base, but without a basal tooth.

Aedeagus ( Fig. 172): rather broad without a marked dorsal flexure.

Ovipositor: short, about as long as wide.

Comments. Specimens of this species with fully developed elytral markings are likely to be confused with M. brittoni sp. n. The pronotal shape and the aedeagus are the main diagnostic features distinguishing the two species. Most specimens examined lack elytral markings, or only have the sutural and humeral vitta developed and sometimes also the pre-apical macula (Fig. 107). By contrast all specimens of M. brittoni examined have a coloured sutural and humeral vittae, median fascia and pre-apical macula. In addition M. septemplagiata usually has the elytral apices slightly produced and the lateral margins slightly sinuate before the apices, whereas in M. brittoni this is usually less pronounced or absent.

Bionomics. Adults collected from September to November. Adults collected on leaves of Acacia sp. (Fabaceae) . Larval hosts unknown.