Maechidius subcostatus , Hell. Determined 1895
Creators: name: Telnov, Dmitry
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Maechidius
Maechidius subcostatus

description: Maechidius subcostatus Heller, 1895
Figs 88, 182–183, 257, 282, 348, 420, 434, 524, 724–725
Type material
Lectotype [herewith designated]
PAPUA NEW GUINEA • ♂; “ K.Wilhelm-Land, Bongu [p, blue label]// Typus [p, pink label]// 10302 [h] // Staatl. Museum für Tierkunde.Dresden [p]”; SNSD.
Paralectotypes
PAPUA NEW GUINEA • 1 ♂; “ Maechidius subcostatus Heller. [h] Determ.K.M.Heller. [p]// K.K. Wilhelm-Land, Bongu [p, bluish label]// Cotypus ♂ [p, pink label]// SYNTYPE Maechidius subcostatus Heller, 1895 labelled by MFNB 2019 [p, red label]”; ZMHB • 1 ♀; “ K.K. Wilhelm-Land, Bongu [p, bluish label]// Cotypus ♂ [p, pink label] // SYNTYPE Maechidius subcostatus Heller, 1895 labelled by MFNB 2019 [p, red label]”; ZMHB • 1 ♀; “ K.Wilhelm-Land, Bongu [p, blue label]// 8186 [h]// Staatl. Museum für Tierkunde.Dresden [p]”; SNSD.
New material
PAPUA NEW GUINEA • 2 specs; “ Bongu [h] K. Wilhelmland [p] 8186 // Staatl. Museum für Tierkunde Dresden [p]”; SNSD • 1 spec.; “ K. Wilhelm-Land, Bongu [p]// 8186 [h] // Staatl. Museum für Tierkunde Dresden [p]”; SNSD • 1 ♂; “ PAPUA: Kokoda. 1,300 ft. ix.1933. L.E.Cheesman. B.M.1933-577.”; BMNH • 3 ♂♂; “ PAPUA: Ishurava. 3,000 ft. vii. 1933. L.E.Cheesman. B.M.1933-577 // Maechidius hirtipes det. G.Frey,1967/68.”; BMNH • 1 ♀; “coll. I. R.Sc.N.B. PAPUA NEW GUINEA Madang Province Canopy Mission Baiteta Light XO 25-IV-1996 Leg Olivier Missa ”; IRSN • 1 ♀; “coll. I. R.Sc.N.B. PAPUA NEW GUINEA Madang Province Canopy Mission Baiteta Light AR 41 30-IV- 1996 Leg Olivier Missa ”; IRSN • 1 ♂; “coll. I. R.Sc.N.B. PAPUA NEW GUINEA Madang Province Canopy Mission Baiteta Light AR 41 01-V- 1996 Leg Olivier Missa ”; IRSN • 1 ♀; “coll. I. R.Sc.N.B. PAPUA NEW GUINEA Madang Province Canopy Mission Baiteta Light AR 8 16-VII-1996 Leg Olivier Missa ”; IRSN • 6 specs; “Collection Naturhistorisches Museum Basel// Papua New Guinea Madang Prov. L. Cizek lgt. // Salemben village 145°24’E 4°42’S 16.XII. 2000, 750 m”; NHMB • 1 spec.; same labels as for preceding; DTC • 2 ♂♂; “PNG, Madang, Baitabag vill., 50m a.s.l., 145°47’E, 5°08’S M. Janda coll., hand collecting 20.iii.2002 // coll. IECA, České Bud ě jovice Czech Republic ”; IECA.
Remarks
Heller (1895: 1) based his description of M. subcostatus on an unstated number of specimens. The single SNSD specimen labelled “Typus” is herewith designated as the lectotype and the specimen with the identical locality label becomes a paralectotype. Two ZMHB syntypes also become paralectotypes. A lectotype is designated 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. Additional SNSD specimens with slightly different labels are not considered syntypes since they have different ID numbers from the lectotype.
Description
MEASUREMENTS. Total body length 7.70–9.00 (lectotype) to 9.70 (largest paralectotype) mm.
Dorsum uniformly black-brown, venter and appendages brown. Head convex dorsally between compound eyes, opaque dorsally and ventrally. Male labroclypeus (Fig. 182) broadly emarginate anteriorly, its lateral margins strongly sinuous in both dorsal and lateral views. Female labroclypeus similar to as in male (Fig. 183). Anterolateral angles rounded, moderately strongly protruding, raised up at angle of nearly 90° to frons in lateral view. Anterior and lateral margins of labroclypeus smooth. Upper- and underside of labroclypeus with sparse inconspicuous setae along anterior and lateral margins. Canthus broadly rounded to obtusely angulate in dorsal view. Punctures of frons irregularly hexagonal, large, dense and shallow. Intervening spaces smooth, much smaller than punctures. Head setae very short, appressed to suberect, not or hardly surpassing length of corresponding punctures.Antenna 9-segmented, club 3-lamellate. Pronotum transverse, flattened dorsally, opaque dorsally and laterally. Anterior margin of pronotum broadly emarginate to slightly sinuous with protruding anterolateral angles, basal margin broadly rounded. Lateral margin of pronotum broadly rounded in dorsal view, deeply emarginate in basal fourth, crenulate in anterior half, denticulate at lateral emargination, smooth to slightly crenulate in emargination area (Fig. 257). Lateral margin of pronotum sinuous in lateral view. Inconspicuous erect seta present between every two crenulae or denticles. Punctures of pronotal disc large, horseshoeshaped, deep and dense. Intervening spaces glossy, distinctly smaller than punctures. Pronotal setae inconspicuous, seta not surpassing length of median ‘bulb’ of horseshoe-like puncture. Hypomeron separated from prosternum by high nearly straight carina, its anterolateral margin slightly angulate medially, with long setae on anterolateral margin opposite to compound eye (Fig. 282). Antennal pocket moderately deep. Scutellar shield narrowly rounded apically. Elytron opaque, with vague tracks of four variously broadly interrupted glabrous longitudinal carinae, including sutural one. Elytral punctures linear (elongate and narrow), incision-shaped, moderately deep. Intervening spaces densely microreticulate (Fig. 348). Appressed to suberect seta rises from anterior margin of each incision, not surpassing length of corresponding incision. Disc and lateral margins of elytra in part covered with microscopical velvety pubescence. Male abdomen with sparse clavate scale-like golden setae (Fig. 434). Male pygidium slightly convex dorsally, with large shallow dense annular punctures, female pygidium flattened dorsally. Intervening spaces microreticulate, distinctly smaller than punctures. Male and female pygidium flattened dorsally, opaque, with dense large and shallow annular punctures (Fig. 524). Setae of pygidium inconspicuous, short and suberect, in anterior part not, in distal part surpassing length of corresponding punctures. Male protibia slightly widened distally, with three external teeth: distal one largest and narrow, median broad and obtuse and basal much smaller, strongly obtuse (Fig. 420). Male protibial terminal spur short and straight, female one longer and stronger pointed. Male metatibial terminal spurs long, unequal, lower spur slightly curved, female one more strongly unequal and straight. Tarsal claws with pulvilli. Underside of male basal metatarsomere with a brush of long dense setae. Aedeagus as in Figs 724–725.
Sexual dimorphism
Female generally more robust, with flattened pygidium, comparatively shorter antennal lamellae and longer protibial terminal spur and more strongly unequal metatibial terminal spurs.
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 115-117, DOI: 10.5852/ejt.2020.721.1127, http://zenodo.org/record/4122118