Maechidius awu Telnov 2020, sp. nov.
Creators: name: Telnov, Dmitry
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Maechidius
Maechidius awu

description: Maechidius awu sp. nov.
urn:lsid:zoobank.org:act: 86803286-3157-4DB2-9A03-6040AD2D2226
Figs 24, 103–104, 202, 292, 364, 457, 537, 579–581
Differential diagnosis
Undoubtedly very close to Sulawesi congeners, differs primarily in shape of male genitalia (cf. Figs 579– 581), comparatively deeper emarginate anterior margin of male labroclypeus and somewhat medially angulate lateral margin of female pronotum (seen in dorsal view). In the shape of the aedeagus, M. awu sp. nov. strongly resembles M. deltouri sp. nov. from North Sulawesi (see description below), but it is readily distinguishable in male pygidium evenly convex (humped posteriorly in M. deltouri sp. nov.), dorsally evenly convex pronotal disc (with circular impression on either side of the midline in M. deltouri sp. nov.) and different shape of parameres (cf. Figs 607–610 for M. deltouri sp. nov.).
Etymology
Named after Awu, the largest volcano in the Sangihe chain, which caused its last powerful eruption in 1966 and developed a 4.5 km wide crater at the summit as a result of this eruption. Noun in apposition.
Type material
Holotype
INDONESIA • ♂; “ Indonesia, 200-600 m alt. SANGIR Isl., Tahuna distr. Bukit Bembaluh, SE of Tahuna 14.- 21.11.2009, St. Jakl lgt. // coll. IECA České Budějovice, Czech Republic”; IECA.
Paratypes (4 specimens)
INDONESIA • 1 ♂, 2 ♀♀; same labels as for holotype; IECA • 1 ♀; same labels as for holotype; DTC.
Description
MEASUREMENTS. Holotype, total body length 7.05 mm. Head 1.50 mm long, across eyes 1.81 mm wide. Pronotum 1.70 mm long, maximum width 2.78 mm. Elytral length 3.85 mm, maximum combined width 3.12 mm. Paratypes 5.30–6.80 mm long.
Dorsum uniformly black to black-brown with reddish brown labroclypeus, mouthparts, antennae, legs and all of venter. Lateral margins of pronotum and elytra, pronotal hypomera and venter with dense microscopical velvety pubescence in some specimens. Head transverse, glossy to subopaque dorsally and ventrally, convex between eyes. Compound eye large, occupying about half side of head. Male labroclypeus (Fig. 103) rather deeply V-like emarginate anteriorly, its lateral margins sinuous in both dorsal and lateral views, anterolateral angles rather strongly protruding, acute in dorsal view, bent up at ~90° to frons in lateral view. Female labroclypeus (Fig. 104) with vague and very broad emargination, its anterolateral angles broadly rounded and not protruding, nearly straight in both dorsal and lateral views. Upper- and underside of labroclypeus with sparse long setae along anterior and lateral margins. Canthus slightly rounded in dorsal view. Anterior and lateral margins of labroclypeus smooth. Dorsal punctures ovoid, large and very deep; inner margin with delicate membrane. Intervening spaces glossy, glabrous, generally distinctly smaller than punctures. Very long erect seta rises from anterior margin of each puncture. Antenna in both sexes 9-segmented, club 3-lamellate. Scape large, with bulbous predistal projection on dorsal side, provided with two very long setae near distal margin. Antennomere 2 trapezoid, transverse. Pronotum glossy dorsally and laterally. Anterior margin sinuous in male (slightly sinuous with anterolateral angles (stronger) and mesal portion protruding anteriad), broadly emarginate in female. Basal margin broadly rounded. Lateral margin of pronotum in dorsal view broadly rounded in male (Fig. 202), straight and widened towards obtuse postmedian angulation and afterwards constricted towards base in female. Lateral margin delicately crenulate all along, a long erect seta present between every two crenulae. Lateral margin of pronotum nearly straight in lateral view. Punctures ovoid, very deep, variably large; inner margin with delicate membrane. Intervening spaces glossy and glabrous, generally narrower than punctures, nearly wrinkled at lateral margins. Setae curved, as on head. Lateral and basal margins, antero- and posterolateral angles partly covered with microscopical velvety pubescence. Hypomeron emarginate and very long setose on anterior margin, which is flange-like protruding. Antennal pocket deep. Median anterior process of prosternum long brushy setose, short, moderately raised. Scutellar shield pointed apically. Elytra slightly widened postmedially, maximum width across midlength, glossy dorsally, with distinct humeri. Vague tracks of two flat glabrous carinae on each elytron. Punctures of elytral disc ovoid, generally smaller and much shallower than those on forebody, irregular to partly arranged in longitudinal rows; inner margin with delicate membrane covered with microscopical velvety pubescence (Fig. 292). Setae long, suberect to erect, sparse, arranged in longitudinal rows. Epipleuron all along with short suberect setae. Male pygidium slightly convex, deeply punctate (Fig. 537). Pygidium intervening spaces subopaque, microreticulate and covered with microscopical velvety pubescence, with sparse moderately long suberect setae. Female pygidium flattened, glossy on intervening spaces. Venter covered with sparse small shallow punctures, each provided with very short seta, in part covered with microscopical velvety pubescence. Legs long and slender. Male protibia straight on external margin, delicately crenulate all along, with complete dorsal fovea (Fig. 457). Two acute, rather large distal teeth on protibia in both sexes, distal longer than predistal. Male protibial terminal spur large, curved, female one shorter and straight. Male metatibial terminal spurs paired, almost equally long, subacute, lower one curved; female ones shorter, nearly straight, obtuse. Tarsal claws with pulvilli in both sexes. Male aedeagus as in Figs 579–581.
Sexual dimorphism
Male with longer lamellae of antennal club, stronger emarginate anterior margin of labroclypeus, dorsally convex pygidium (flat in female), larger and curved pro- and lower metatibial terminal spurs, and evenly rounded lateral margin on pronotum (in dorsal view).
Ecology
Studied specimens sampled at 200–600 m altitude.
Distribution
Hitherto only known from Sangir, the largest of the Sangihe Islands. This is hitherto the northernmost record of the Maechidiini.
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 24-26, DOI: 10.5852/ejt.2020.721.1127, http://zenodo.org/record/4122118