Melobasis dives, Carter

Levey, Brian, 2012, 3464, Zootaxa 3464, pp. 1-107 : 56-57

M. dives Carter

( Figs. 22, 128)

Melobasis dives Carter 1923:92 ; 1929:284; Obenberger 1930:430; Bellamy, 2002:150; 2008:1320. Type locality: Northern Territory, Roper River.

Type specimens examined. Holotype ♀ ( MVMA): Roper R I, N.T.3.3.16/ TYPE ♀ / TYPE f / Melobasis dives Carter, Id. by H.J. Carter.

The description of the Holotype was done many years ago, and some characters described in related species were not recorded at the time. Unfortunately I have not seen any other specimens. The specimen was not dissected and although labelled as ♀, the quadrate distal antennal segments would suggest that the specimen might be ♂.

Diagnosis. General diagnosis: length 13.0 mm; head reddish-copper with the bottoms of the punctures goldengreen; pronotum and elytra reddish-copper at centre, becoming golden-copper laterally; pronotum with dark blueblack admedian vittae, which do not quite reach the apical margin and are slightly divergent basally; elytra with the following blue-black markings: an elongate vitta opposite the pronotal admedian vittae, not quite reaching the base of the elytra, slightly diverging from one another apically and extending slightly beyond the mid point of the elytra; a bisinuate transverse fascia at the basal third which extends narrowly along the suture almost to the scutellum and apically more broadly along the suture terminating as an approximately sagittate (arrow head shaped) mark; underside and appendages dull reddish-purple; underside sparsely clothed with moderately long pubescence.

Head: densely and strongly punctured with large round punctures; sparsely clothed with moderately long silvery white pubescence; unpunctured areas with microreticulate sculpture; clypeal excision shallow, V-shaped, with a microreticulate unpunctured border which is much broader at the centre; clypeal peaks almost right angled; vertex flat, but slightly depressed in the midline, about half width of head across eyes when viewed from above; eyes weakly convex.

Antenna: serrate from segments 4-10, expanded part of segment 4 triangular, expanded part of segments 5-10 almost quadrate, occupying almost the whole length of the segment.

Pronotum: 1.57 times as wide at base as long in midline; anterior margin moderately strongly bisinuate with a well developed broad median lobe; posterior margin moderately strongly bisinuate; widest at basal angles, the lateral margins with a slight sinuation just anterior to the basal angles, thence weakly convergent to mid-length before more strongly curvilinearly converging to the apical angles; about as wide at base as elytra at base; lateral carina about three-quarters complete; punctation of central area between the admedian vittae dense and strong, punctation of admedian vittae moderately dense, becoming very dense lateral to the admedian vittae, punctures round; surface between the punctures microreticulate and with pin-prick punctures; a large deep poorly defined central fovea at the base, without an unpunctured median line; short sparse pubescence confined to the apical angle and the immediate vicinity of the lateral carina.

Scutellum: almost round, about one-twelfth width of elytra at base, microreticulate with a large puncture at the base.

Elytra: basal margin moderately strongly bisinuate; slightly widening over the humeral callosities, then parallel sided for a short distance before narrowing in the basal quarter, thence almost parallel sided to about the midlength, before narrowing to the broadly rounded apices; lateral margins in apical half and apices coarsely serrate; sutural margins raised in apical third; inner half of elytra sparsely and weakly punctured over the copper coloured areas, very sparsely and very weakly punctured over the blue-black markings; outer half of elytra very densely to contiguously punctured with much larger, stronger punctures, becoming somewhat transversely rugose near the humeral callosities; without seriate punctation or costate interstriae.

Proepisternum: densely punctured with large punctures, and sparsely clothed with long pubescence.

Prosternal process: slightly widening posteriorly, sparsely punctured with small weak punctures, without a line of partly contiguous punctures or groove close to the lateral margin.

Mesoepisternum: microreticulate with sparse, small, very weak punctures and a few large punctures near the internal apical margin.

Apical sternite ( Fig. 22): with lunate punctures, moderately dense laterally, sparser and weaker at centre; excision moderately shallow about 2 times as wide as deep, the distal margin of the flange straight and the lateral spines slightly divergent, short, shorter than the depth of the flange.

Comments: The elytral markings of this species are very unusual, and this species cannot be confused with any other known species. The elytral markings could be derived by the fusion of expanded copper coloured humeral and sutural vittae, median fasciae and pre-apical macula like those seen in M. r. regalis Carter.

Bionomics: Unknown.