Melobasis nervosa (Boisduval, 1835)

Levey, Brian, 2018, A revision of the Australian species of the genus Melobasis Laporte & Gory 1837 (Coleoptera: Buprestidae), Part 2 (Revision of the nervosa species group), Zootaxa 4528 (1), pp. 1-79 : 5-7

Key to the nervosa species group

1. Elytra distinctly bicoloured, with vittae, fasciae or maculae, or most of the elytra lateral to the 1 st costa of a different colour to the area internal to the 1 st costa (Figs 1–16)................................................................. 2

- Elytra essentially unicoloured, although the lateral margin in the apical half, the apices and part of the sutural margin may be of a different colour to the rest of the elytra (Figs 17–38)....................................................... 13

2 Elytra with a narrow continuous sinuate vitta extending from the base almost to the apex (Figs 1, 2).................... 3

- Elytra without a narrow continuous vitta extending from the base almost to the apex................................ 4

3 Lateral spines of apical ventrite in male parallel (Fig.100); elytral apices of male obsoletely toothed and sometimes truncated near the suture (Fig. 212), weakly toothed in female, without a much enlarged sutural tooth (Fig. 213); W. Australia................................................................................. M. cupreovittata westralica ssp. n.

- Lateral spines of apical ventrite in male slightly to strongly turned in towards the mid-line (Fig. 98); elytral apices of male weakly toothed near the suture, sometimes with a slightly enlarged sutural tooth (Fig. 214), with a slightly to greatly enlarged sutural tooth in female (Fig. 215); S. Australia, N.W. Victoria and New South Wales ...................................................................................................... M. cupreovittata cupreovittata Saunders

4 Elytra with a humeral vitta, two median vittae or maculae and a pre-apical macula or vitta (Figs 3–8)................... 5

- Elytral markings different to the above................................................................... 10

5 Elytral maculae and vittae small and sometimes not very obvious to the unaided eye; at least the humeral vitta and the lateral median vitta confined to the costae, humeral vitta sometimes absent; other vittae and maculae also more obvious on the costae (Fig. 6); each elytron with four very well defined costae; basal angle and part of lateral margin of pronotum usually fiery red, and contrasting with the blackish bronze colour of the rest of the pronotum; W. Australia (mainly near the coast).......................................................................................... M. interstitialis Blackburn

- Elytral maculae and vittae larger and not confined to the costae; at least the 4 th costa poorly defined.................... 6

6 Elytral apices acute; elytral markings brownish copper; the humeral vitta continued along the basal and lateral margins and almost joined to a large lateral median macula; internal median macula very small; Eltham, Victoria (a single female in MVMA)................................................................ M. vertebralis Carter ( ssp. uncertain )

- Elytral apices not acute; elytral markings rarely brownish copper; if humeral vitta continued along the lateral margin then well separated from the lateral median macula; internal median macula large.......................................... 7

7 Underside reddish copper medially, laterally and most of apical ventrite blue or blue-black; pre-apical macula nearly always about as wide as long; humeral vitta strongly widened at the apex (Figs 4, 5); S. & C. Queensland ............................................................................................ M. cupreovittata queenslandica ssp. n.

- Underside rarely reddish copper; if so then not blue or blue-black laterally although sometimes darkened; pre-apical macula always longer than wide; humeral vitta not or only slightly widened at the apex (Figs 3, 7, 8)......................... 8

8 Internal median macula usually only as long as the lateral median macula, elongate oval to ellipsoidal, extending onto the 1 st and often the 2 nd costa; pre-apical macula wide, less elongate (Figs 7, 8); W. Australia............................... 9

- Internal median macula much longer than the lateral median macula, usually almost parallel sided and confined to the area between the 1 st and 2 nd costae, rarely extending onto the costae; pre-apical macula narrow, very elongate (Fig. 3); S. Australia, N.W. Victoria and N.E. New South Wales ................................... M. cupreovittata cupreovittata Saunders 9 Prosternal process more strongly, more densely punctate (Fig. 185); lateral margin of elytra with small but obvious serrations at the level of the anterior margin of the pre-apical macula; only 1 st costa of elytra well developed; median lobe of anterior margin of pronotum scarcely developed (Fig. 7); front-clypeal excision fairly deep U-shaped (Fig. 151); W. Australia............................................................................................. M. fortipunctata sp. n.

- Prosternal process more weakly, less densely punctate (Fig. 186); lateral margin of elytra with serrations only developed posterior to the pre-apical macula; 1 st and 2 nd costae of elytra well developed at least at the mid-length, 3 rd costa sometimes obvious at the mid-length; median lobe of anterior margin of pronotum moderately developed (Fig. 8); fronto-clypeal excision slightly shallower, U-shaped (Fig. 152); W. Australia.............................................. M. breviserrata sp. n.

10 Elytra with a silvery green or blue humeral vitta, single elongate median macula in the lateral half, and a sutural vitta extending almost to the apex; form moderately broad (Fig. 16); C. Queensland ........................... M. quadrinotata Carter

- Elytral markings different; form more elongate............................................................. 11

11 Apical ventrite in ♂ with the flange moderately narrowly produced at the centre, as a transverse truncated lobe (Fig. 110); elytra with a copper coloured humeral vitta or macula, transverse median fascia (sometimes constricted at middle) and pre-apical macula (Fig. 9); C. Queensland ..................................................... M. brevimaculata sp. n.

- Apical ventrite in ♂ with flange very narrowly produced at the centre, as an elongate truncated lobe (Fig. 116) or with the flange broadly produced at the centre as a rounded to subtruncate lobe (Fig. 114); elytra lateral to the 1 st costa almost entirely copper coloured (Figs 10–12) or with the middle part of the copper coloured area partly broken up (Figs 13–15)......... 12

12 Lateral parts of underside very densely pubescent, the pubescence largely concealing the punctation; apical ventrite in ♂ with the flange broadly produced at the centre as a rounded to subtruncate lobe (Fig. 114); aedeagus less elongate (Fig. 59); subspecies from Queensland ......................................................... M. vertebralis vertebralis Carter

- Lateral parts of underside less densely pubescent, the punctation mostly visible; apical ventrite in ♂ with the flange very narrowly produced at the centre as an elongated truncated lobe (Fig. 116); aedeagus more elongate (Fig. 55, 57); subspecies from New South Wales and Queensland ................................................. M. vertebralis cuneata ssp. n.

13 At least inner two-thirds of mesanepisternum densely punctate with large setae bearing punctures, the surface largely obscured by the setae (Fig. 183)................................................................................. 14

- Mesanepisternum varying from almost completely shiny and impunctate, to densely punctate in the anterior half, but the surface not obscured by setae except sometimes at the anterior internal corner (Figs 173–181).......................... 19

14 Apex of elytra with a much enlarged tooth near the suture (Fig. 17); excision of apical ventrite in male with a narrow bisinuate flange (Fig. 118); aedeagus (Figs 67, 68); W. Australia....................................... M. costifera Thomson

- Apex of elytra without or with a less enlarged tooth; excision of apical ventrite in male with a truncate or semicircular flange (Figs 120, 122, 124, 126).............................................................................. 15

15 Mesanepisternum densely punctate with setae bearing punctures over the whole surface; lateral parts of underside densely punctate and densely clothed with pubescence; aedeagus with apical setae bearing part gradually widening from base, widest in anterior half (Figs 70,72)........................................................................... 16

- Mesanepisternum with at least a small obvious impunctate area at the external fifth; lateral parts of underside less densely punctate and less densely clothed with pubescence; aedeagus with apical setae bearing part rather abruptly widening from base, widest at mid length (Fig. 74), or apical setae bearing part scarcely widening (Figs 76, 78)..................... 17

16 Pronotum slightly less transverse, not obviously flattened on disc, the lateral margins strongly curved in apical half; 1 st costa of elytra very broad, with three irregular rows of pin-prick punctures for most of its length; lateral margin of elytra with small obsolete serrations (Fig. 18); lateral parts of underside very densely punctate and densely clothed with pubescence which largely obscures the punctation; apical ventrite of male with a truncate flange (Fig. 120); aedeagus with apical setae bearing part about one-third total length of parameres (Fig. 69); W. Australia............................ M. latecostata sp. n.

- Pronotum slightly more transverse, flattened on disc, the lateral margins very weakly curved in apical half; 1 st costa of elytra narrower, with only one or two irregular rows of pin-prick punctures for most of its length; lateral margins of elytra with larger serrations (Fig. 19); lateral parts of underside less densely punctate and less densely clothed with pubescence, which only slightly obscures the punctation; apical ventrite of male with a semicircular flange (Fig. 126); aedeagus with apical setae bearing part about one-quarter total length of parameres (Fig. 71); W. Australia....................... M. planithorax sp. n.

17 Apices of elytra reddish violet or lilac (Fig. 24); excision of apical ventrite in female as broad or broader than deep (Fig. 123); aedeagus with apical setae bearing part rather abruptly widening from base (Figs 73, 74); S. Australia, W. Australia (this species shows considerable geographical variation but I have not described subspecies due to insufficient specimens)............................................................................................. M. igniceps Saunders

- Apices of elytra sometimes darkened but not reddish violet or lilac; excision of apical ventrite in female deeper than broad (Fig. 125); aedeagus with apical setae bearing part scarcely widening from base (Figs 75–78)........................ 18

18 Elytra strongly narrowing in apical third to the acute or sub-acute apices; elytra often with a coppery reflection (Fig. 23); coastal areas of Carnarvon and Pilbara biogeographic regions of W. Australia......... M. angustecostata subacuta ssp. n.

- Elytra less strongly narrowing in apical third to the more or less rounded apices; elytra rarely with a coppery reflection (Fig. 21); this subspecies has a wide distribution from the Geraldton Sandplain and Swan Coastal Plain inland to the Avon Wheatbelt of W. Australia, and the Murray Darling Depression region of W. Victoria, and the Northern Territory .................................................................................... M. angustecostata angustecostata ssp. n.

19 Vertex at narrowest point slightly more than one-third width of the head across the eyes when viewed from above (Figs 26, 162); mesanepisternum, unpunctured, shiny, mirror like (Fig. 173); aedeagus (Figs 63, 64); species from N. Queensland ........................................................................................ M. kaszabi (Pochon)

- Vertex at narrowest point almost, or more than half the width of the head across the eyes when viewed from above (e.g Figs 38, 161) mesanepisterum not shiny, mirror like; species not from N. Queensland ...................................... 20 20 Elytra with at least four rows of regularly seriate punctation at the mid-length in the internal half, the intervals between these rows with a single irregular row of slightly smaller punctures; apex of elytra with the most apical tooth much larger than those between it and the end of the suture (Fig. 38); prosternal process with a line of larger punctures along the lateral margins (Fig. 187); aedeagus (Figs 65, 66); S. Australia, Victoria & New South Wales ........................ M. viridiceps Saunders

- If elytra with four rows of regularly seriate punctation at the mid-length in the internal half, then apex of elytra with the most apical tooth scarcely larger than those between it and the end of the suture, and species from W. Australia only; prosternal process rarely with a line of much larger punctures along the lateral margin......................................... 21

21 Punctation at the centre of the pronotum very dense, consisting of strongly transverse punctures (Fig. 29); lunate puncture near lateral margin of apical ventrite coalescent (Figs 133, 134); at least part of the posterior half of the mesanepisternum microreticulate (Fig. 179); upperside of male largely brown-bronze or greenish bronze (Fig. 29), underside largely reddish purple, the head and sometimes part of the pronotum, prosternum, prosternal process, mesosternum, part of the metaventrite and anterior faces of the legs, green; female usually lacking the contrasting green areas shown by male except for antenna and anterior faces of the fore legs; aedeagus (Figs. 81, 82); all states except N. Territory & Tasmania ................. M. sordida Blackburn

- Without the above characters combined................................................................... 22

22 Punctation of central-fifth to central-quarter of pronotum very sparse, and consisting of very small often pin-prick punctures (Fig. 25); aedeagus with the parameres gradually narrowing in apical half before the apical setae bearing parts which are rather strongly widened (Figs 79, 80); all states except N. Territory & W. Australia.................... M. nervosa (Boisduval)

- Very small punctures, when present, confined to the central-eighth or less of the pronotum; aedeagus with parameres more abruptly narrowing in apical half and/or apical setae bearing parts less strongly widened (Figs 83–97)................. 23

23 Punctation between the 1 st and 2 nd costae of elytra arranged in regular longitudinal series adjacent to the costae; sexes differing in colour; males golden-green (Fig.30), females blackish bronze to olive-green (Fig. 31); excision of apical ventrite in male with a narrow oblong flange at the centre (Fig. 137); aedeagus (Figs 86, 87)......................... M. dissimilis sp. n.

- Punctation between 1 st and 2 nd costae of elytra not arranged in regular longitudinal series; sexes similar or differing in colour; excision of apical ventrite in male with a differently shaped flange at the centre (Figs 135, 139, 141, 143, 145, 147)...... 24

24 Lunate punctures of apical ventrite contiguous but not forming incipient grooves close to the lateral margin; pubescence of head and pronotum not very conspicuous; aedeagus with parameres very abruptly narrowing in apical half, the apical setae bearing part very strongly widened at the apex (Figs 83–85)............................ M. lathami (Laporte & Gory)

- Lunate punctures of apical ventrite mostly well separated near the lateral margin and pubescence of head and pronotum short and not very conspicuous, that on the lateral parts of the pronotum scarcely visible, and not longer than the associated punctures, or lunate punctures of apical ventrite partly coalescent or forming incipient grooves close to the lateral margin and pubescence of head and pronotum longer and fairly conspicuous, that on the lateral parts of the pronotum at least slightly longer than the associated punctures; aedeagus with apical setae bearing part much less widened at apex (Figs 88–97)...... 25

25 Pubescence of head and pronotum short and not very conspicuous, that on the lateral parts of the pronotum scarcely visible, and not longer than the associated punctures; underside usually at least partly green; lunate punctures of apical ventrite mostly well separated near the lateral margin.................................................................... 26

- Pubescence of head and pronotum longer and fairly conspicuous, that on the lateral parts of the pronotum at least slightly longer than the associated punctures; underside brownish bronze or reddish purple, without any green colouration; lunate punctures of apical ventrite partly coalescent or forming incipient grooves close to the lateral margin...................... 27

26 Mesanepisternum partly microreticulate and/or punctate with numerous small punctures in the posterior half (Fig. 176); excision of apical ventrite in male with a wide semicircular flange at the centre (Fig. 139); elytral apices more or less rounded or obtusely angled; upperside usually golden green in male, bronze green or brownish copper in female (Figs 32, 33); tip of median lobe of aedeagus sub-truncate (Figs 88, 89); W. Australia.......................... M. costipennis Kerremans

- Mesanepisternum shiny in the posterior half or sparsely punctate with small punctures (Fig. 177); excision of apical ventrite in male with a narrower flange at the centre (Fig. 141); elytral apices usually almost acutely angled; upperside usually bronze green or brownish copper in both sexes (Fig. 34); tip of median lobe of aedeagus sub-acutely rounded (Figs 90, 91); W. Australia........................................................................... M. rubromarginata Saunders

27 2 nd elytral costa extending almost to the basal margin (Fig. 35); flange of apical ventrite of male narrow (Fig. 145); aedeagus with narrower apical part of parameres shorter than basal part (Fig. 92); coastal area of W. Australia between Perth & Shark Bay.......................................................................... M. soror basicostata ssp. n.

- 2 nd elytral costa not extending baseward beyond the level of the middle of the humeral callosity (Figs 36, 37); flange of apical ventrite in male wider (Figs 143, 147) inland W. Australia, S. Australia & W. Victoria .............................. 28

28 Aedeagus with narrower apical part of parameres much shorter than basal part (Fig. 94); pronotum strongly narrowed behind the widest point to hind angles (Fig. 36); inland W. Australia, S. Australia & W. Victoria ......... M. soror soror Blackburn

- Aedeagus with narrower apical part of parameres almost as long as basal part (Fig. 96); pronotum weakly narrowed behind the widest part to hind angles (Fig. 37); S.W. Australia (Coolgardie Biogeographic Region)................. M. barkeri sp. n.