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 heterosquamosus Heller, 1910 comb. rest. Figs 42–43 , 124–125 , 216 , 267 , 306 , 380, 473 Maechidius heterosquamosus Heller, 1910: 23 . Paramaechidius clypeatus Frey, 1969: 508 syn. nov. Type material Lectotype of M. heterosquamosus (herewith designated) PAPUA NEW GUINEA • ♀ ; “[upper side of label] Kais.Wilhelmsland Toricelli [sic ♂ ] Gebirge [p] [underside of label] 640 m [h] [blue label]// 1910 [p] 1 [h] [blue label]// [upper side of label] typus [p] [underside of label] heterosquamosus [h] [red label]// Staatl. Museum für Tierkunde.Dresden [p]”; SNSD . Holotype of M. clypeatus PAPUA NEW GUINEA • ♂ ; “ NEW GUINEA : NE. Torricelli Mts. Mobitei, 750 m . II-28-III-4 -’59 [p] // W.W. Brandt Collector Bishop [p] // Type [h, red label]// TYPE Paramaechidius clypeatus n sp det. G.Frey ,1967/68 [p]”; NHMB . Remarks The paratype of M. clypeatus from NHMB ( Frey 1969: 508 ) belongs to Maechidius lapsus sp. nov. Heller (1910: 23) likely based his description of M. heterosquamosus comb. rest. on a single specimen, although not explicitly stated. The single SNSD specimen labelled “typus” is herewith designated as lectotype in order to enhance the stability of nomenclature and fix the specimen I based my redescription and new synonymy on, in case other syntypes are discovered in the future. Description MEASUREMENTS. Total body length 7.00– 8.10 mm ( lectotype of M. heterosquamosus comb. rest.). Dorsum and venter uniformly brown. Head strongly convex dorsally between eyes, glossy dorsally and ventrally. Female labroclypeus ( Figs 124–125 ) broadly emarginate anteriorly, its lateral margins nearly straight in dorsal, slightly sinuous in lateral view.Anterolateral angles acute, protruding, raised up at angle of nearly 80-90° to frons in lateral view. Anterior and lateral margins of labroclypeus smooth. Underside of labroclypeus with sparse long setae, upper side with clavate short setae along lateral margins. Canthus straight in dorsal view. Punctures of frons ovoid, very deep and dense, on periphery encircled with dense microscopical velvety pubescence. Intervening spaces glossy, generally smaller than punctures. Setae moderately long, scale-like, suberect to erect, variably strongly clavate to fusiform. Female antenna 9-segmented, club 3-lamellate. Pronotum transverse, glossy dorsally and laterally. Anterior margin of pronotum broadly emarginate with protruding anterolateral angles, basal margin broadly rounded. Lateral margin of pronotum sinuous in lateral view, with obtuse median protruding in dorsal view, slightly emarginate anteriorly and somewhat stronger towards base, delicately (indistinctly) crenulate all along ( Fig. 216 ). Clavate erect seta present between every two crenulae. Lateral margin of pronotum sinuous in lateral view. Hypomeron emarginate and long setose on anterior margin which is flange-like ( Fig. 267 ). Antennal pocket deep. Pronotal punctures deeper than those on head, of variable shape (ovoid to hexagonal). Scale-like clavate seta rises from anterior margin of each puncture. Lateral, basal margins and hypomeron covered with dense microscopical velvety (fur-like) pubescence ( Fig. 267 ). Scutellar shield pointed apically. Elytron opaque, with five raised glabrous partly interrupted longitudinal carinae, including sutural one. Punctures of elytral disc irregular, small to rather large, deep, of variable shape ( Fig. 306 ). Intervening spaces hidden under dense microscopical velvety pubescence. Pronotal setae scale-like, short to rather long, strongly to less strong clavate, suberect to erect. Obtuse partially glossy hump near apex. Female pygidium slightly longitudinally impressed dorsally, with dense deep ovoid punctures (except on anterior margin) and long dense erect scale-like clavate (medially) to ordinary (along posterior margin) setae. Elytral setae generally pointing obliquely to middle of pygidium. Midline of female pygidium generally sparser punctured, in part glabrous ( Fig. 473 ). Intervening spaces glossy, covered with fur-like microscopical pubescence except along midline. Venter covered with extremely delicate fur-like microscopical pubescence. Protibia slightly widened distally, dorsally with delicate longitudinal carina, in female with two large distal external teeth of which distal one is stronger and narrower (Fig. 380). Female protibial terminal spur short, nearly straight. Female metatibial terminal spurs strongly unequal, lower one about twice as long as upper. Tarsal claws without pulvilli (in females only?). Figs 42–45. Papuan Maechidius Macleay, 1819 , habitus, dorsal view. 42 . M. heterosquamosus Heller, 1910 comb. rest., lectotype, ♀ (SNSD). 43 . Same, ♂, holotype of M. clypeatus ( Frey, 1969 ) comb. nov. (BPBM). 44 . M. hirtipes Arrow, 1941 , lectotype, ♂ (BMNH). 45 . M. humeralis Heller, 1914 , lectotype, ♂ (SNSD). Not to scale. Sexual dimorphism This species’ male genitalia were not studied.