Key to species of the genus Neobubastes

1 Frons flat, pronotum weakly bell-shaped, lateral pronotal margins straight in posterior half or weakly emarginate anteriorly of rectangular posterior angles; head and pronotum coppery-red, elytra dark blue-green with red base and lateral margins (Fig. 1); 10.0–18.0 mm; N.T., S.A., V., W.A. ................................................................................................ N. aureocincta Blackburn, 1892

- Frons convex, lateral pronotal margins regularly rounded, posterior angles obtuse-angled; entire body unicolorous or elytra dark green with wide, yellow, longitudinal stripes.................................................................................................................................... 2

2 Sculpture of pronotum homogeneous consisting of dense, simple, deep punctures; antennae short, hardly reaching midlength of lateral pronotal margins when laid alongside; vertex and pronotal disc black-green, frons and lateral sides of pronotum with purple tinge; elytra dark metallic green, each elytron with wide, yellow, longitudinal stripe not reaching elytral apex; (Fig. 2); 8.0– 17.0 mm; W.A. ........................................................................................................................................ N. flavovittata Carter, 1922

- Sculpture of pronotum rough consisting of coarse, rounded or somewhat transversely widened punctures and short transverse rugae; pronotum usually with short, narrow and glabrous, medial line; antennae long reaching posterior two thirds of lateral pronotal margins when laid alongside; body unicolorous, black or blue-violet..................................................................................... 3

3 Entire body blue, blue-green or blue-violet, female—ventral surface bright blue-green, male—ventral surface red-copper; pronotum and elytra asetose, ventral surface with very short and sparse, white pubescence; (Fig. 3); 8.0–15.0 mm; W.A........................ ............................................................................................................................................................ N. nickerli (Obenberger, 1928)

- Entire body black with fine blue-violet or bronze lustre, ventral surface black-bronze; lateral sides of pronotum and elytra with sparse, semierect, white pubescence, ventral surface with long, dense, almost lanuginose, recumbent, white pubescence (Figs. 4, 5); 8.5–14.2 mm; W.A. ......................................................................................................................................... N. obscura sp. nov.