Melolonthini sensu Britton 1978

Allsopp, Peter G., 2022, Australian Melolonthini (Coleoptera: Scarabaeidae: Melolonthinae): reclassification of eight species to Antitrogus Burmeister, 1855 and Barryfilius new genus, Zootaxa 5213 (5), pp. 513-545 : 537-538

Key to genera of Australian Melolonthini sensu Britton 1978

1 Dorsal surface clothed with adpressed, circular to broadly ovate, white scales contained within their punctures ( Figs. 1 , 26 ), sometimes sparse; antennal club with 3 lamellae in both sexes, club shorter than shaft; aedeagus with parameres often asymmetrical and sometimes grossly modified............................................. Lepidiota Kirby, 1828

- Dorsal surface clothed without adpressed, circular to broadly ovate, white scales contained within their punctures; antennal club with 3–8 lamellae, often sexually dimorphic, club often longer than shaft; aedeagus with parameres symmetrical or asymmetrical but never grossly modified.................................................................. 2

2 Dorsal surface with white or yellowish, flattened, overlapping setae that are teardrop-shaped and taper to a fine point, often abraded on part or most of surface; antennae with 5 lamellae in males, 4 lamellae in females; parameres asymmetrical, short and about as long as high; northeastern Queensland ..................................... Dermolepida Arrow, 1941

- Dorsal surface with inclined, fine, acute, yellow-brown or white setae or without setae or scales or with short, fine, semierect setae ( Figs. 2–6 , 14–18 ); antennae with up to 8 lamellae, lamellae often long in males; aedeagus with parameres symmetrical or near to symmetrical................................................................................. 3

3 Antennae with 9 antennomeres, club with 3 lamellae......................................................... 4

- Antennae with 10 antennomeres, club with 3–8 lamellae...................................................... 5

4 Metafemur strongly distended; metatibia strongly expanded at apex; mesotarsomere 1 as long as 2 and 3 combined; clypeus semicircular in outline; posterior angles of pronotum rounded; body approximately 16 mm long; northern Northern Territory .............................................................................. Holorhopaea Britton, 1978

- Metafemur not unusually distended; metatibia not strongly expanded at apex; metatarsomere 1 as long as 2 only; posterior angles of pronotum prominent; body approximately 10 mm long; northern Western Australia ... Nanorhopaea Britton, 1978

5 Pretarsal claws without a tooth; antennal club of 8 long, equal lamellae; clypeofrontal suture raised and angulate laterally; body 14–17 mm long; central Australia..................................................... Zietzia Blackburn, 1894

- Pretarsal claws with a tooth, either prominent and near middle or small and close to the base; antennal club with 3–8 lamellae, basal lamellae often shorter than apical lamellae; clypeofrontal suture not raised or angulate......................... 6

6 Anterior faces of prefemora and protibiae setose or bare, but without flattened, adpressed, white setae.................. 7

- Anterior faces of prefemora and/or protibiae bearing at least a few broad or elongate, adpressed, white scales or flattened, adpressed setae (sometimes almost all abraded) in addition to fine, yellow setae.................................. 11

7 Elytra clothed with recumbent setae, long and very dense or shorter but dense; disc of pronotum may have longer setae in addition............................................................................................ 8

- Elytra bare or sparsely clothed with setae, if appearing recumbent on elytra then disc of pronotum with only long setae; posterior pronotal angles obvious........................................................................ 9

8 Antennal club of 3 lamellae, males with club slightly shorter or longer than antennomeres 2–7 combined; eastern Queensland and northeastern New South Wales ...................................................... Alepida Allsopp, 2018

- Antennal club of 5–8 lamellae, males with club much longer than shaft; southeastern Queensland to southeastern South Australia ........................................................................ Rhopaea Erichson,1847

9 Labrum strongly projecting, deflexed; antennal club of 7 lamellae; upper surface of clypeus less transverse, ratio of greatest width to mid length <2.3, surface usually strongly concave; central and Western Australia ... Pararhopaea Blackburn, 1911

- Labrum not strongly projecting and not deflexed; antennal club of 3, 6, 7, or 8 lamellae; if 7 lamellae then clypeus transverse, ratio of greatest width to mid length> 2.5, and surface not strongly concave..................................... 10

10 Antennal club of 8 lamellae, inner edges of lamellae serrate; metafemora strongly inflated; northern Western Australia ................................................................................... Megacoryne Britton, 1987

- Antennal club of 3–7 lamellae, inner edges of lamellae not serrate; metafemora not strongly inflated; eastern Australia.................................................................................. Antitrogus Burmeister, 1855

11 Anterior face of clypeus very broad and shallow, about 8 times as wide as mid length, with a single transverse row of setae; eastern Queensland and northeastern New South Wales ................................... Metatrogus Britton, 1978

- Anterior face of clypeus deeper, less than 7 times as wide as mid length, surface with scattered setae.................. 12

12 Antennal club of 8 lamellae in males, 7 lamellae in females; labrum projecting far beyond clypeus; body 33–37 mm long; southern South Australia and southern Western Australia ................................ Megarhopaea Britton, 1978

- Antennal club of 7 or fewer full-length lamellae; labrum much less projecting; body 30 mm or less long............... 13

13 Tooth on pretarsal claws minute and very close to the base; pronotum clothed with long, backwardly directed white setae in addition to scattered, shorter, elongate, flattened white setae; elytra with sparse, white, elongate setae; antennal club with 7 lamellae; body approximately 7 mm long; northern Northern Territory ........................ Microrhopaea Lea, 1920

- Tooth on pretarsal claws obvious; elytra with a few long setae close to the base, otherwise punctures with minute, stout, yellowbrown or white setae; pronotum with long, erect yellow-brown setae only on anterior and posterior margins; antennal club of 6 or 7 lamellae; body greater than 11 mm long.............................................................. 14

14 Labrum deeply excavated anteriorly; male antennal club with 7 full-length lamellae, or with 6 full-length and one half-length lamellae; upper surface of clypeus deeply concave; northern Australia................ Pseudholophylla Blackburn, 1911

- Labrum not or only slightly excavated anteriorly; male antennal club with 3–6 full-length lamellae but with some development on other antennomeres; upper surface of clypeus slightly concave............................................. 15

15 Anterior face of clypeus shallow, ratio of greatest width to mid depth> 6.6; body greater than 17 mm long; northeastern Queensland (possibly northeastern Northern Territory, but doubtful).................... Barryfilius Allsopp , new genus

- Anterior face of clypeus wide, ratio of greatest width to mid length <6; body 11–17 mm long; northeastern Queensland and northwestern Northern Territory ......................................................................... 16

16 Surface of clypeus with at least some longer, white or pale yellow backwardly directed setae in addition to elongate, flattened, adpressed setae contained within or slightly longer than their punctures; abdominal ventrites not obliterated in middle, clothed with fine, yellow setae; northeastern Queensland and northwestern Northern Territory ......... Allothnonius Britton, 1978

- Surface of clypeus with only elongate, flattened, adpressed setae contained within their punctures; abdominal ventrites fused, clothed with dense, flattened, white setae; northeastern Queensland ......................... Hypolepida Britton, 1978

Figures

FIGURES 1–6. Setal and scale types on pronota of Australian Melolonthini. 1, White, rounded scales, contained within the puncture—Lepidiota podicalis Moser, 1913; 2, white, elongate setae, largely contained within the puncture—Hypolepida wilsoni Britton, 1978; 3, white, elongate setae, longer than the puncture—Antitrogus ciliatus (Britton, 1978); 4, mixture of long setae and white, flattened setae—Allothnonius barretti Britton, 1978; 5, long thin, yellow-brown setae—Rhopaea decipennis Lea, 1919; 6, recumbent, flattened, tapered, finely pointed setae—Holorhopaea sagata Britton, 1978. Figs. 1, 5 by SAM; Figs. 2–4 by Queensland Museum; Fig. 6 reproduced from Weir et al. (2019) (CSIRO, used with permission).

FIGURES 26–28. Lectotype of Lepidiota oblonga Brenske, 1900. 26, Dorsal view; 27, ventral view; 28, labels. Photographs by Museum für Naturkunde.

FIGURES 14–18. Adult males of Barryfilius species, dorsal views. 14, Barryfilius contiguus (Britton, 1978); 15, B. laevis (Arrow, 1932); 16, B. lewisae (Britton, 1978); 17, B. quinarius (Britton, 1978); 18, B. vernus (Britton, 1978). Photographs by Greg Daniels.