Maechidius esau Heller 1914
Creators: name: Telnov, Dmitry
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Maechidius
Maechidius esau

description: Maechidius esau Heller, 1914
Figs 2–3, 36–37, 118–119, 213, 303, 376, 470, 561, 614–616
Maechidius setosellus Frey, 1969: 500 syn. nov.
Maechidius setosus Moser, 1920: 17 syn. nov.
Type material
Lectotype of M. esau (herewith designated)
PAPUA NEW GUINEA • ♂; “ N.Guinea [p, blue label]// Gehr.W.Müller Vermächt. 1909 [p, blue label]// Typus! [p] esau Heller [h, red label] // Staatl. Museum für Tierkunde.Dresden [p]”; SNSD.
Lectotype of M. setosus (herewith designated)
PAPUA NEW GUINEA • ♂; “ Maechidius setosus Mos. Type [h] // D. Neu-Guinea [p] Stephansort// SYNTYPE Maechidius setosus Moser, 1920 labelled by MFNB 2019 [p, red label]”; ZMHB.
Holotype of M. setosellus
PAPUA NEW GUINEA • ♂; “ Holotype [p, label circular, red frame] // Stn. No. 28. [p] // NEW GUINEA: Madang Dist. R. Buru, c. 90 m. N.W.Lae 1200 ft. 1.x.1964 [p]// Type Maechidius setosellus n. sp. [h] det. G.Frey,1967//86 [p]// M.E.Bacchus. B.M. 1965-120. [p] // TYPUS [p, red label]”; BMNH.
Paratype of M. setosellus
PAPUA NEW GUINEA • ♂; “ Paratype [p, label circular, yellow border] // NEW GUINEA: Madang Dist. R. Buru, c. 90 m. N.W.Lae 1200 ft. 1.x.1964 [p] // M.E.Bacchus. B.M. 1965-120. [p] // PARATYPE [p, red label]// Maechidius setosellus n. sp. [h] det. G.Frey,1967/68 [p]”; BMNH.
New material
PAPUA NEW GUINEA • 2 specs; “ TERR. PAPUA & NEW GUINEA: Maprik. 17.x.1957. J.Smart // Brit.Mus.1957-693.”; BMNH • 2 specs; “ TERR. PAPUA & NEW GUINEA: Maprik. 18.x.1957. J.Smart // Brit.Mus.1957-693.”; BMNH • 1 spec.; “ TERR. PAPUA & NEW GUINEA: Maprik. 19.x.1957. J.Smart // Brit.Mus.1957-693.”; BMNH • 1 spec.; “ TERR. PAPUA & NEW GUINEA: Maprik. 24.x.1957. J.Smart // Brit.Mus.1957-693.”; BMNH • 5 specs; “ TERR. PAPUA & NEW GUINEA: Maprik. 26.x.1957. J.Smart // Brit.Mus.1957-693.”; BMNH • 5 specs; “ TERR. PAPUA & NEW GUINEA: Maprik. 28.x.1957. J.Smart // Brit.Mus.1957-693.”; BMNH • 22 specs; “Stn. No. 28.// NEW GUINEA: Madang Dist., R. Buru, c. 90 m. N.W.Lae 1200 ft. I. x.1964 // M.E. Bacchus. B.M. 1965-120.”; BMNH • 1 ♀; “ Papua New Guinea Wau 1500 m Aug.1983 M. Mastaller leg.”; SMNS.
Remarks
Heller (1914: 627) likely based his description of M. esau 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. Moser (1920: 17) based his description of M. setosus on an unstated number of specimens. The single ZMHB syntype is therefore designated as lectotype. 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. Frey (1969: 500) described M. setosellus from two specimens captured near locality that M. setosus was described from.
Description
MEASUREMENTS. Total body length 8.70 (lectotype M. esau) to 10.10 mm (lectotype M. setosus).
Dorsum and venter uniformly black or brown. Head flattened dorsally, glossy to subopaque dorsally and ventrally. Male and female labroclypeus very broadly V-shaped emarginate anteriorly (Figs 36– 37), its lateral margins sinuous in both dorsal and lateral views. Anterolateral angles broadly rounded, 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 moderately long setae along anterior and lateral margins. Canthus nearly straight in dorsal view. Punctures of frons irregularly circular, moderately large to large, rather deep, their backgrounds shagreened. Intervening spaces microreticulate, variably large. Setae long, suberect. Antenna 9-segmented, club 3-lamellate. Pronotum transverse, flattened dorsally, glossy to subopaque dorsally and laterally. Anterior margin of pronotum broadly emarginate with protruding anterolateral angles, basal margin broadly rounded. Lateral margin of pronotum slightly gradually widened in anterior half, slightly constricted postmedially, nearly straight at base, crenulate all along (Fig. 213). Extraordinarily long erect seta present between every two crenulae, at least as long as longitudinal diameter of compound eye in fresh specimens. Lateral margin of pronotum sinuous in lateral view. Punctures of pronotal disc generally sparser than those on head, circular to annular (in basal third of disc), intervening spaces glossy, generally larger than punctures. Hypomeron separated from prosternum by low straight carina, with moderately long setae on anterolateral margin opposite to compound eye (Figs 2–3). Pronotal setation as on head, stronger appressed. Scutellar shield rounded apically. Elytron glossy to subopaque, with vague tracks of longitudinal carinae. Punctures of elytral disc double (Fig. 303). Ordinary punctures of disc shallow and rather dense, irregular in size and shape. Each ordinary puncture supplemented with a shallow linear (narrow and long) incision-shaped puncture. Intervening spaces in part microreticulate, in part glossy, generally larger than ordinary punctures. Elytral setae moderately long, erect to suberect. Some setae longer and stronger erect, arranged in poorly defined longitudinal rows. Lateral margin of elytra with extraordinarily long erect setae. Male and female pygidium slightly convex dorsally, with large shallow annular punctures (Fig. 470). Intervening spaces glossy, variably large. Setae of pygidium long, erect to suberect; each seta rises from either anterior margin or centre of corresponding puncture. Protibia widened distally, dorsally with delicate longitudinal carina, with two large acute distal external teeth and much smaller basal one (Fig. 376). Male protibial terminal spur not present. Male metatibial terminal spurs long, nearly equally long. Distal margin of metatibia in both sexes with projection over basal metatarsomere. Tarsal claws with pulvilli. Spiculum gastrale as in Fig. 561. Aedeagus as in Figs 614–616.
Sexual dimorphism
Female lamellae of antennal club distinctly shorter; female labroclypeus comparatively shallower emarginate anteriorly.
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 45-46, DOI: 10.5852/ejt.2020.721.1127, http://zenodo.org/record/4122118