A revision of the Maechidiini Burmeister, 1855 (Coleoptera: Scarabaeidae: Melolonthinae) from the Indo-Australian transition zone, and the first record of the tribe west of Wallace’s Line Author Telnov, Dmitry text European Journal of Taxonomy 2020 2020-10-19 721 1 210 journal article 9693 10.5852/ejt.2020.721.1127 0cd61b23-1089-4c1b-bfc0-487887abad84 4122118 89E62EF8-2E45-4C59-94B7-6A5603E8939B Maechidius leucopsar sp. nov. urn:lsid:zoobank.org:act: 6D5298A8-F6E1-4361-B7CA-62C55B85C1DB Figs 52 , 132 , 225 , 316 , 357 , 389, 485, 550, 643–645 Differential diagnosis This new species is undoubtedly very close to Maechidius suwawa sp. nov. from North Sulawesi (see description of this species below) and other congeners. It differs primarily in the male genitalia (cf. Figs 643–645 , 726–729 ), the shape of the male metatibial terminal spurs, the absence of glossy elytral carinae (two flat glossy glabrous carinae on each elytron in M. suwawa sp. nov. ), a less coarsely punctured pronotum (punctures of pronotal disc smaller, ovoid, deeper in M. leucopsar sp. nov. than in any Sulawesi species), the punctures of the elytral disc are circular and less regular (elytral punctures ovoid, substriate in M. suwawa sp. nov. ), and the comparatively deeper emarginate anterior margin of the labroclypeus. Etymology Named after Leucopsar Stresemann, 1912, the monotypical sturnid genus of the famous and critically endangered Bali endemic Leucopsar rothschildi Stresemann, 1912, widely known as the Bali myna, Rothschild’s mynah, or Bali starling. Type material Holotype INDONESIA • ♂ ; “Indonesia, Bali Isl. Bedugul Region , Tamblingan Lakes N.R. XI.2004 , 1200 m // coll. IECA České Budějovice, Czech Republic”; IECA . Paratype INDONESIA • 1 ♂ ; same labels as for holotype; IECA . Description MEASUREMENTS. Holotype , total body length 6.60 mm . Head 1.30 mm long, across eyes 1.47 mm wide. Pronotum 1.50 mm long, maximum width 2.50 mm . Elytral length 3.80 mm , maximum combined width 3.26 mm . Dorsum uniformly black with reddish brown labroclypeus, mouthparts, antennae, legs and all of venter. Head transverse, glossy to subopaque dorsally and ventrally, somewhat convex between eyes and vaguely impressed on labroclypeus anterior to each compound eye. Compound eye large, occupying about half side of head. Male labroclypeus ( Fig. 132 ) very shallowly broadly emarginate anteriorly, its lateral margins sinuous in both dorsal and lateral views, anterolateral angles weakly protruding, obtuse in dorsal view, bent up at ~80–90° to frons in lateral view. Upper- and underside of labroclypeus with sparse moderately long setae along anterior and lateral margins. Canthus nearly straight in dorsal view. Anterior and lateral margins of labroclypeus smooth. Head dorsal punctures circular to ovoid, deep, smaller on labroclypeus than on frons; inner margin of some punctures with delicate membrane. Intervening spaces glossy to very delicately microreticulate, glabrous, variably large. Suberect thickened moderately long scale-like seta rises from anterior margin of each puncture, surpassing length of corresponding puncture. Antenna 9-segmented, club 3-lamellate. Scape large, with bulbous predistal projection on dorsal side, provided with two very long setae near distal margin. Antennomere 2 trapezoid, transverse. Pronotum glossy dorsally and laterally. Anterior margin of pronotum broadly emarginate, anterolateral angles protruding anteriad. Vague dorsal impression beyond anterolateral angle on either side. Basal and lateral margins broadly rounded. Crenulae of lateral margin delicate, a long suberect seta present between every two crenulae ( Fig. 225 ). Lateral margin of pronotum nearly straight in lateral view. Pronotal punctures ovoid, very deep, variably large; inner margin of some punctures with delicate membrane. Intervening spaces glossy and glabrous, in part wrinkled, generally smaller than punctures except near lateral margins. Setae shorter than those on frons. Lateral and basal margins, antero- and posterolateral angles partly covered with dense microscopical velvety pubescence ( Fig. 357 ). Hypomeron shallowly emarginate and very long setose on anterior margin which is flange-like. Antennal pocket deep. Median anterior process of prosternum long brushy setose, short, moderately raised. Scutellar shield rounded apically. Elytra slightly widened in posterior half, maximum width across midlength, glossy dorsally, with distinct humeri. Punctures of elytral disc irregular in shape and size, generally much shallower than those on pronotal disc; on periphery partly or completely encircled with dense microscopical velvety pubescence ( Fig. 316 ). Setae inconspicuous, in part minute, in part moderately large and surpassing length of corresponding punctures. Epipleuron all along with very short appressed setae. Male pygidium slightly convex dorsally, circularly punctate, subopaque microreticulate on intervening spaces, spaces generally smaller than punctures, with moderately long suberect seta that rises from each puncture ( Fig. 485 ). Venter covered with sparse small shallow punctures, each provided with very short seta. Legs long and slender. Male protibia nearly straight on external margin, delicately crenulate in basal third, with almost complete dorsal fovea. Two acute rather large distal teeth on male protibia, distal longer than basal one (Fig. 389). Male protibial terminal spur large, curved. Male metatibial terminal spurs obtuse, the lower stronger curved than upper one. Tarsal claws with large pulvilli (in male only?). Spiculum gastrale as in Fig. 550 . Male aedeagus as in Figs 643–645 . Sexual dimorphism Female is unknown. Variability Paratype elytral disc less coarsely punctured. Ecology Occurs at an altitude of about 1200 m . Distribution Hitherto only known from Bali , the westernmost of the Lesser Sunda Islands . This is hitherto the westernmost record of the Maechidiini .