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 milneanus Heller, 1914 Figs 60 , 148–149 , 233 , 325 , 398, 494, 670–672 Type material Lectotype [herewith designated] PAPUA NEW GUINEA • ♀ ; “Neu Guinea Milne-Bay [p, blue label] // 1910 [p] 18 [h] [blue label]// Typus ♂ [p] milneanus H. [h, red label] // Staatl. Museum für Tierkunde.Dresden [p]“; SNSD . Paralectotype PAPUA NEW GUINEA • 1 ♀ ; “Neu Guinea Milne-Bay [p, blue label]// 1910 [p] 18 [h] [blue label]// Staatl. Museum für Tierkunde.Dresden [p]”; SNSD . New material PAPUA NEW GUINEA • 15 specs (♂♀); “ Milnebay N.Guinea // W.H. MUCHE Radeberg, Ankauf [p] // Staatl.Museum für Tierkunde Dresden [p]”; SNSD . Remarks Heller (1914: 628) based his description of M. milneanus on an unstated number of specimens. Since two specimens with identical locality data are present in SNSD (and a number of specimens with slightly different labels – see above), the lectotype designated here is the only syntype with Heller’s original “typus” handwriting on a red label, which, without confidence, may indicate that this specimen was selected by the original author as the holotype . The lectotype designation is made in order to enhance the stability of nomenclature and fix the specimen I based my redescription on, in case other syntypes are discovered in the future. Description MEASUREMENTS. Total body length 7.30–9.10 ( lectotype ) mm. Dorsum and venter uniformly brown, appendages somewhat paler, forebody with greenish metallic lustre. Head convex dorsally on frons between compound eyes, subopaque dorsally and ventrally. Labroclypeus ( Figs 148–149 ) in both sexes very broadly shallowly emarginate anteriorly, its lateral margins strongly sinuous in both dorsal and lateral views. Anterolateral angles broadly rounded, hardly protruding, raised up at angle of nearly 80-90° to frons in lateral view. Anterior and lateral margins of labroclypeus smooth. Upper- and underside of labroclypeus with sparse moderately long setae along anterior and lateral margins. Canthus strongly obtusely angulate in dorsal view. Punctures of frons circular to hexagonal, in part annular, large and shallow. Intervening spaces glossy, variably large. Setae inconspicuous, appressed, generally not surpassing length of corresponding punctures. Antenna 7-segmented, club 3-lamellate. Pronotum transverse, flattened dorsally, subopaque dorsally and laterally. Anterior margin of pronotum broadly emarginate with protruding anterolateral angles, basal margin broadly rounded. Lateral margin of pronotum broadly rounded in dorsal view, strongly crenulate all along ( Fig. 233 ). Lateral margin of pronotum sinuous in lateral view. Short suberect seta present between every two crenulae. With small circular vague median impression on either side of disc. Hypomeron separated from prosternum by low nearly straight carina, with moderately long setae on its anterolateral margin opposite to compound eye. Antennal pocket shallow. Punctures of pronotal disc large, circular to ovoid, dense, annular. Intervening spaces distinctly smaller than punctures. Pronotal setae inconspicuous, appressed; each seta rises from anterior margin of corresponding puncture, not surpassing its length. Scutellar shield narrowly rounded apically. Elytron subopaque, without or with vague tracks of four flat longitudinal carinae, including sutural one. Surface of elytral disc wrinkled and with sinuous (long and narrow) incision-shaped punctures. Intervening spaces microrugulose ( Fig. 325 ). Elytral setae inconspicuous, appressed, not surpassing length of corresponding incisions. Male and female pygidium flattened dorsally, with large shallow annular punctures ( Fig. 494 ). Intervening spaces glossy, variably large. Setae of pygidium short, inconspicuous, sparse, generally not surpassing length of corresponding punctures except several long suberect ones along posterior margin of pygidium. Protibia widened distally, with three external teeth (Fig. 398). Male protibial terminal spur very short, female one longer and very narrow. Male metatibial terminal spurs long, nearly equally long, female lower metatibial spur distinctly longer than the upper. Tarsal claws with pulvilli. Sexual dimorphism Female lamellae of antennal club shorter; protibial terminal spur longer and more slender than in male.