Melobasis brittoni, Levey, 2012

Levey, Brian, 2012, 3464, Zootaxa 3464, pp. 1-107 : 30-31

M. brittoni sp. n.

(Figs. 106, 169, 203)

Type locality: Western Australia, Wurarga, Marloo sheep station (28°24'S 116°29'E) .

Type specimens examined. Holotype ♂ ( ANIC) Marloo Stn., Wurarga, W.A. 1931–1941 A. Goerling./ HOLOTYPE Melobasis brittoni sp. n. ♂ B. Levey 2010. Paratypes as follows. Western Australia: 11 ♂, 6 ♀ ( ANIC, NMWC) same data as Holotype; 2 ♂ ( ANIC) Wurarga W.A. Goerling; 2 ♂, 1♀ ( BMNH) Wurarga W.A., A. Goerling, 10.36, 1939-140; 3 ♂, 1♀ ( ZMHB) W. Australien, Marloo Station, Wurarga, 1938, A. Goerling S.G.; 2 ♂ ( SAMA) Ankertell W.A., H.W. Brown/ Co-Type HJC/ J. 15349, Melobasis septemplagiata Cart., W. Australia, Co type/ M. septemplagiata Cart. id by H.J. Carter; 1♀ ( WAMA) Cue W.A., H.W. Brown/ M. septemplagiata Cart. / du Boulay coll./ 72-507; 1 ♂ ( WAMA) Cue W.A., H.W. Brown/ M. septemplagiata / du Boulay coll./ 72-506/ Comp. with ♂ from S. Aust. Mus. labelled Holotype M. septemplagiata Cart. B. Levey det. 1974; 1 ♀ ( TMSHC) 62 km E. of Yalgoo WA, T.M.S. Hanlon, 4 September 2008, on fine leaf Acacia ;; 1 ♂ ( MPC) 35km N. of Byro Hmstd. WA, Acacia lvs. 29/09/04, M. Powell/ D. Knowles.

Diagnosis. General diagnosis: length 9.3–10.4 mm; head and pronotum brownish-, greenish- or black-bronze, the central half of the pronotum and the head usually with extensive blue and purple reflections; elytra brownishcopper to reddish-purple with the apices more or less extensively suffused with a reddish-violet or violet colour, with the following silvery-blue, silvery-green or pinkish-copper, markings: a sutural vitta in the basal quarter, sometimes joined to the humeral vitta along the basal margin and extending onto the epipleura to the level of the posterior coxa; a humeral vitta of the same length or slightly shorter; a sinuate median transverse fascia which is sometimes joined to the sutural vitta; a roughly obovate pre-apical macula; underside brownish- or greenishbronze; lateral parts of underside moderately densely clothed with fairly long silvery pubescence.

Head: upper third of vertex densely punctured with fairly large round to ovate 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; moderately densely to densely clothed with long silvery pubescence; unpunctured areas shiny to weakly microreticulate; clypeal excision rather shallow to moderately deep, U-shaped, with an unpunctured weakly to strongly microreticulate border, sometimes only well developed at centre of excision; clypeal peaks slightly acute to obtuse; vertex flat, slightly more than half the width of head across eyes when viewed from above; eyes weakly to moderately 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 more or less quadrate.

Pronotum: 1.48–1.58 times as wide at base as long in midline; anterior margin strongly bisinuate, with a well developed broad median lobe; posterior margin bisinuate; widest at or near mid-length; lateral margins almost parallel for a short distance in front of posterior angles before diverging to widest point, or weakly diverging to widest point from posterior angles, thence moderately strongly curvilinearly converging to the anterior angles; slightly narrower at base than elytra at base; lateral carina slightly sinuate, about half to three-quarters complete; punctation sparse 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 clothed with fairly long silvery pubescence in lateral half.

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

Elytra: 2.50–2.70 times as long as wide at the base; basal margin weakly to moderately strongly bisinuate; slightly widening from base over the humeral callosities; thence almost parallel sided or very slightly rectilinearly widening to the mid-length, before narrowing to the very slightly attenuated rounded apices; lateral margins from just beyond mid-length and apices with moderately coarse acute serrations; sutural margin strongly raised in apical half; inner half external of the subsutural depression often with at least traces of three costate intervals, the costate interval adjacent to the subsutural depression being better defined; 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 well defined bead at the anterior margin at almost the same level as the area behind; prosternal process slightly widening distally, sparsely punctured with small round or pin-prick punctures, with an irregular line of larger punctures near the lateral margin, and a line of partly coalescent punctures, sometimes forming a groove, next to the unpunctured lateral margin; glabrous or with a few setae near the margin.

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

Apical sternite: with the lunate punctures coalescent near the lateral margin, but not forming well defined ridges; excision fairly deep, in ♂ about one and a half times as wide as deep, the lateral spines moderately developed, but not as long as depth of the flange ( Fig. 203); in ♀ excision about twice as wide as deep, the spines shorter; distal margin of flange straight.

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

Aedeagus ( Fig. 169): elongate with a marked dorsal flexure.

Ovipositor: short, about as long as wide.

Comments. This species is similar to M. septemplagiata Carter , the pronotal shape and the aedeagus being the main diagnostic features distinguishing the two species. See comments under M. septemplagiata Carter for other differences.

Etymology. This species is named after the late E. B. Britton who facilitated my visit to the museums in Australia in 1974, when I embarked upon this revision.

Bionomics. Adults collected in September and October. Adults collected on leaves of Acacia sp. (Fabaceae) . Larval hosts unknown.