Melobasis angusta, Levey, 2012

Levey, Brian, 2012, 3464, Zootaxa 3464, pp. 1-107 : 68-69

M. angusta sp. n.

(Figs. 130, 192)

Type locality: Western Australia, Cunderdin .

Type specimens examined. Holotype ♂ ( WAMA) Cunderdin, W.A. Aug.–Sept. 1913, 8045A/ M. superba / HOLOTYPE ♂ Melobasis angusta sp. n. B. Levey 2010. Paratypes as follows: Western Australia : 2♂ ( WAMA, NMWC) same data as Holotype but 8045 C and 8045 D ; 1♂ ( WAMA) 48 – 2980, Kukerin / M. superba ; 1♂ ( WAMA) 48– 2180, Merredin / M. superba . 1♀ ( ANIC) Cunderdin .

Diagnosis. General diagnosis: length 7.8–10.2 mm; ♂ head with frontoclypeus and lower three-quarters of vertex bright green with coppery reflections, upper quarter of vertex deep purple, ♀ dark brown-bronze; ♂ central half of pronotum reddish-purple, violet-blue or bluish-green, lateral half bright green sometimes with a coppery reflection, ♀ entirely blackish-bronze; scutellum bright green or golden; elytra deep purple-brown, with the following bright green to golden markings: a poorly defined sutural vitta in the basal seventh; an elongate humeral vitta slightly more than one-quarter the length of the elytra; a sinuate transverse median fascia extending from the subsutural depression to about the lateral third of the elytra; a slightly elongate pre-apical macula; ♂ underside bright green, sometimes with coppery reflections, ♀ blackish-olive to brownish-bronze; whole of underside moderately densely clothed with moderately long to long silvery pubescence.

Head: very densely to contiguously punctured with small strong punctures, which partly coalesce to form dorso-ventrally orientated series on the lower half to two-thirds of the head; densely clothed with long silvery pubescence; unpunctured areas shiny; clypeal excision very shallow, U-shaped, with an unpunctured shiny or microreticulate border; clypeal peaks acute; vertex flat, slightly less than three-fifths width of head across eyes when viewed from above; eyes strongly convex.

Antenna: serrate from segment 4–10, the segments becoming progressively smaller and slightly less elongate, in ♂ the expanded part of the segments is quadrate, except segment 4 which is triangular, in ♀ the expanded part of all segments more or less triangular.

Pronotum: 1.40–1.58 times as wide at base as long in midline; anterior margin strongly bisinuate, with a strongly produced median lobe; anterior beaded margin narrow, but well defined; posterior margin bisinuate; widest at mid-length; lateral margins parallel sided for a short distant in front of posterior angles, before strongly diverging to mid-length, then strongly curvilinearly converging to the anterior angles; as wide at base as elytra at base; lateral carina slightly sinuate, about half to two-thirds complete; punctation dense medially, consisting of small round punctures, punctures becoming progressively larger and very dense laterally; sometimes with traces of an unpunctured midline; sometimes with a small well marked depression near the lateral margin just behind the midlength; shiny to weakly microsculptured; with some moderately long silvery pubescence close to the lateral margin.

Scutellum: roughly shield-shaped, microsculptured, depressed at centre, about one-twelfth width of elytra at base.

Elytra: 2.26–2.43 times as long as wide at base; basal margin weakly to moderately strongly bisinuate; slightly widening from base over the humeral callosities, thence parallel sided to slightly beyond mid-length, before narrowing to the rounded apices; lateral margins in apical two-fifths and apices with acute serrations; sutural margins slightly raised in apical third; with a well marked costate interval next to the subsutural depression; subsutural depression sparsely punctured with very small round punctures; lateral to the costate interval the punctures become progressively larger and denser, becoming contiguous towards the lateral margin where they form short transverse series; weakly microreticulate.

Proepisternum: contiguously punctured with fairly small shallow ovate punctures, partly obscured by moderately dense long silvery pubescence.

Prosternum: with a poorly defined bead at the anterior margin, the anterior margin at almost the same level as the area behind; prosternal process slightly widening distally, densely punctured with small round punctures, with a groove formed from contiguous punctures close to the lateral margin for its entire length; densely clothed with long silvery pubescence.

Mesoepisternum: shiny, with numerous very small variably shaped punctures.

Apical sternite: with small lunate punctures, sometimes partly coalescent and forming short transverse series near the lateral margin; excision shallow crescent-shaped about twice as wide as deep, the lateral spines only slightly developed.

Mid tibia: ♂ curved, rather swollen, with a long setae-filled depression on the ventral face, ♀ slightly curved, without a setae-filled depression.

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

Aedeagus ( Fig. 192): very long and narrow; apical setae-bearing part of parameres with long fine setae only.

Comments: This species is only likely to be confused with some forms of M. g. gloriosa having similar elytral and pronotal markings. The much longer and denser pubescence on the head and prosternal process, and the narrower shape will distinguish it from M. g. gloriosa .

Etymology. This species is named from its narrow shape.

Bionomics. Adult collected in August–September. Larval hosts unknown.