Maechidius pauxillus Heller 1910
Creators: name: Telnov, Dmitry
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Maechidius
Maechidius pauxillus

description: Maechidius pauxillus Heller, 1910 comb. rest.
Figs 71, 160–161, 243, 275, 333, 406, 505–506, 685–687
Type material
Lectotype [herewith designated]
PAPUA NEW GUINEA • ♂; “ K.Wilhelm Land, Bongu [p, blue label] // [upper side of label] typus [p] [underside of label] pauxillus Heller [h] [red label]// Staatl. Museum für Tierkunde.Dresden [p]”; SNSD.
New material
PAPUA NEW GUINEA • 14 specs; “Stn. No. 46.// NEW GUINEA: Madang Dist., Finisterre Mts. Damanti 3,550 ft. 2-11.x.1964 // M.E. Bacchus. B.M. 1965-120.”; BMNH • 1 spec.; “Stn. No. 51. // NEW GUINEA: Madang Dist., Finisterre Mts. Budemu c. 4000 ft. 15-24.x.1964 // M.E. Bacchus. B.M. 1965- 120. // Paramaechidius pauxillus det. G.Frey, 1967/68”; BMNH.
Remarks
Heller (1910: 24) likely based his description of M. pauxillus 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 on, in case other syntypes are discovered in the future.
Description
MEASUREMENTS. Total body length 5.20–5.65 (lectotype) to 6.10 mm.
Dorsum and venter uniformly brown. Dorsum almost completely covered with microscopical velvety pubescence. Head humped dorsally between eyes, opaque dorsally and ventrally. Male labroclypeus (Fig. 160) broadly emarginate anteriorly, its lateral margins sinuous in both dorsal and lateral views. Anterolateral angles acute, strongly protruding, raised up at angle of nearly 90–95° to frons in lateral view. Female labroclypeus less deeply emarginate on anterior margin (Fig. 161). Anterior and lateral margins of labroclypeus smooth. Underside of labroclypeus with sparse long setae along anterior and lateral margins. Canthus straight in dorsal view. Dorsal sculpture of head almost completely obscured by dense suberect strongly clavate scales. Punctures of frons ovoid, deep and dense. Setae scale-like, dense, more or less strongly clavate, suberect to erect. Male antenna 9-segmented, club 3-lamellate. Pronotum transverse, opaque dorsally and laterally. Anterior margin of pronotum sinuous with median part (slightly) and anterolateral angles (stronger) protruding, basal margin broadly slightly sinuous. Lateral margin of pronotum sinuous, nearly straight in anterior two thirds, constricted afterwards towards base, delicately (indistinctly) crenulate all along (Fig. 243). Clavate short seta present between every two crenulae. Lateral margin of pronotum straight in anterior two thirds, curved in basal third in lateral view. Hypomeron hardly emarginate and long setose on anterior margin which is flange-like (Fig. 275). Antennal pocket deep. Pronotal punctures deeper than those on head, irregularly ovoid. Median ones provided with minute seta at anterior margin not surpassing midlength of corresponding puncture. Lateral and anterior margins very densely scale-like clavate setose. Scutellar shield narrowly rounded apically. Elytron opaque, with vague tracks of two longitudinal carinae plus broadly interrupted glabrous remnants of sutural one. Punctures of elytral disc irregular, ovoid, deep, intervening spaces irregularly large (Fig. 333). Majority of elytral setae minute, not surpassing midlength of corresponding puncture. Numerous large scale-like clavate setae arranged in several irregular longitudinal rows. Obtuse partially glossy hump near apex. Male pygidium covered with microscopical velvety pubescence, slightly impressed dorsally in anterior part, transversely humped medially, flattened otherwise (Fig. 505). Punctures of pygidium rather deep and dense, circular to ovoid, intervening spaces (when exposed from under velvety pubescence) glossy. Setae of pygidium scale-like, mostly not surpassing length of corresponding punctures, with several much larger clavate erect scales in central part. All scales pointing obliquely to middle. Female pygidium with generally larger scale-like setae than male (Fig. 506). Male pygidium sometimes with transverse row of scale-like setae, is/ is not interrupted medially. Protibia narrow, delicately crenulate along external margin. Distal teeth virtually not present: remnants of two inconspicuous ones can be tracked (Fig. 406). Male protibial terminal spur curved. Male metatibial terminal spurs strongly unequal, the curved lower one about twice as long as straight upper one. Male tarsal claws with pulvilli. Aedeagus as in Figs 685–687.
Sexual dimorphism
Female claws without pulvilli. Apex of female elytron without conspicuous protrusion. Female pygidium generally flat (not transversely humped), with a transverse row of dense scale-like elongate setae.
description: Published as part of Telnov, Dmitry, 2020, 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, pp. 1-210 in European Journal of Taxonomy 721 on pages 93-95, DOI: 10.5852/ejt.2020.721.1127, http://zenodo.org/record/4122118