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 aroae Heller, 1914 Figs 23 , 101 , 201 , 290 , 363, 456 Type material Lectotype [herewith designated] PAPUA NEW GUINEA • ♀ ; “14716 [h] // Typus ♂ [p] Aroae Heller [h, red label]// Staatl. Museum für Tierkunde.Dresden [p]”; SNSD . Heller (1914: 627) based his description of M. aroae on an unstated number of specimens. The single SNSD specimen labelled “Typus♂” is herewith designated as the lectotype in order to enhance the stability of nomenclature and fix the specimen that I based my redescription on, in case other syntypes are discovered in the future. Description MEASUREMENTS. Total body length 9.60 mm ( lectotype ). Dorsum and venter uniformly black-brown with exception of paler brown appendages and labroclypeus. Head flattened dorsally, subopaque dorsally and ventrally. Female labroclypeus very broadly emarginate anteriorly ( Fig. 101 ), its lateral margins nearly straight in dorsal, sinuous in lateral view. Anterolateral angles of labroclypeus very broadly rounded, not protruding, raised up at angle of nearly 90° to frons in lateral view. Anterior and lateral margins of labroclypeus smooth. Underside of labroclypeus with sparse long setae along anterior and lateral margins. Canthus very broadly rounded in dorsal view. Punctures of frons circular, moderately large and shallow. Intervening spaces microreticulate, generally much larger than punctures. Pubescence delicate, variably long, appressed. Some setae very short, much shorter than corresponding punctures. Each seta rises from anterior margin of corresponding puncture. Female antenna 8-segmented, club 3-lamellate (antenna 7-segmented according to Frey (1969)) . Pronotum transverse, flattened dorsally, subopaque dorsally and laterally. Anterior margin emarginate with anterolateral angles protruding anteriad. Basal margin subtruncate. Lateral margin of pronotum broadly rounded, somewhat more strongly constricted in basal fourth, crenulate in anterior, denticulate in posterior half ( Fig. 201 ). Long distally curved erect seta present between every two crenulae / denticles. Lateral margin of pronotum slightly sinuous in lateral view. Punctures circular to ovoid, shallow. Intervening spaces as large as to larger than punctures. Hypomeron separated from prosternum by low straight carina, with extraordinarily long setae on anterolateral margin opposite to compound eye. Antennal pocket shallow. Scutellar shield subtriangular, narrowly rounded apically. Elytron glossy, with vague tracks of two vague glabrous longitudinal carinae. Sutural carinae not present. Punctures of disc sparse, narrow and rather deep, linear incision-shaped ( Fig. 290 ). Inconspicuous suberect seta rises from under anterior margin of each puncture; setae generally longer than corresponding punctures. Intervening spaces in part microreticulate, micropunctate or wrinkled. Setae inconspicuous, short, suberect. Female pygidium flattened dorsally, with large annular punctures ( Fig. 456 ). Intervening spaces glossy, smaller than punctures except along midline. Female protibia widened distally, with three large external teeth: two larger acute distal and one obtuse basal (Fig. 363). Protibial terminal spur not present. Female metatibial terminal spurs short, apically rounded. Tarsal claws with pulvilli (in females only?). Figs 22–24. Papuan and Wallacean Maechidius Macleay, 1819 , habitus, dorsal view. 22 . M. angusticeps Arrow, 1941 , holotype, ♂ (BMNH). 23 . M. aroae Heller, 1914 , lectotype, ♀ (SNSD). 24 . M. awu sp. nov. , holotype, ♂ (IECA). Not to scale. Sexual dimorphism Male is unknown.