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

description: Maechidius bintang sp. nov.
urn:lsid:zoobank.org:act: D31E9842-D637-451B-A79A-8E4E188EEF7F
Figs 26–27, 102, 204, 294, 366, 460, 568, 586–588
Differential diagnosis
This new species strongly resembles Maechidius pauxillus Heller, 1910 comb. rest. and M. speciosus (Frey, 1969) comb. nov. (both from Finisterre Mts., NE New Guinea), distinguishable primarily by the structure of the male genitalia (laterally dentate parameres, in particular), lateral margins of pronotum hardly converging anteriad in anterior third (constricted in most specimens of M. pauxillus comb. rest. and in holotype of M. speciosus comb. nov., Figs 41, 46), less strong transverse pronotum which is about 1.3 × as broad as long (1.8–1.9 × in M. pauxillus comb. rest., 1.7 × in M. speciosus comb. nov.), absence of lateral median tooth-like angulation on pronotum (widest part of pronotum is on acute median angulations in M. speciosus comb. nov., Fig. 46), pronotal disc coarser and denser punctured, and the opaque surface of the elytra (elytra smooth in M. speciosus comb. nov.).
Etymology
Toponymic. The name derives from Penugungan Bintang, an Indonesian name for the Star Mountains, on the southern foothills of which this species was first collected. Noun in apposition.
Type material
Holotype INDONESIA • ♂; “INDONESIA E, New Guinea, Papua Prov., Star Mountains, Oksibil 22-27 km SSE, 5 km around Beringin vill. (05°05’01”S, 140°43’27”E), 320-250 m, 12-14.III.2018, primary & secondary lowland rainforest”; NME.
Description
MEASUREMENTS. Holotype, total body length 7.95 mm. Head 1.50 mm long, across eyes 1.86 mm wide. Pronotum 1.80 mm long, maximum width 2.35 mm. Elytral length 4.55 mm, maximum combined width 3.40 mm.
Dorsum dark brown to black, elytra with irregular slightly paler markings, especially along carinae. Dorsal colouration covered by numerous paler scale-like setae (see below). Venter uniformly dark brown. Head transverse, subopaque dorsally and ventrally, with large slightly prominent compound eyes occupying over half side of head. Frons with large obtuse hump at inner margin of each eye. Male labroclypeus (Fig. 102) with broad shallow emargination, its lateral margins sinuous in dorsal, nearly straight in lateral view. Anterolateral angles acute, protruding anteriad and raised up at angle of nearly 90° to frons in lateral view. Anterior margin of labroclypeus smooth and with dense round punctures. Canthus nearly straight in dorsal view. Punctures of frons deep, of irregular oblong shape, small to large. Intervening spaces vary strongly in size, in part glossy and glabrous, in part covered with microscopical velvety pubescence. Except on anterior margin of labroclypeus, suberect dirty yellowish scale-like seta rising from each puncture. Setae smaller and more rounded on anterior and basal parts of head dorsum, becoming elongate clavate and smaller along frons midline (therefore midline looks sparser setose), but becoming very large and strongly clavate, in part suberect, on dorsal humps and along inner margins of eyes (Fig. 102). Anterior margin of labroclypeus with row of long cilia-like setae, lateral margins with elongate-clavate scales. Male antenna 9-segmented, club 3-lamellate. Scape large, strongly clavate-like widened and very densely microreticulate, provided with several long erect setae on posterior margin and with two very long erect setae in distal half of anterior margin. Antennomere 2 short and broad, transverse. Pronotum transverse, subopaque laterally but shiny on disc. Anterior margin of pronotum slightly sinuous with anterolateral angles and mesal portion slightly protruding anteriad. Basal margin of pronotum very broadly rounded. Lateral margins of pronotum almost parallel in anterior half, slightly constricted in basal third, up to constriction all along with weakly defined crenulae, constriction area nearly smooth (Fig. 204). Lateral margin of pronotum hardly sinuous in lateral view. Pronotal punctures coarse and deep, variably oblong on disc, becoming smaller and regularly circular but hardly shallower at lateral margins. Setae dirty yellowish, scale-like, generally tiny to very large seta rising from anterior margin of each puncture. Setae longer clavate and erect mesally on anterior margin, arranged in two longitudinal groups facing frons’ humps (Figs 26, 204). Between these two groups and posterior to them setae minute (not surpassing length of corresponding punctures), but again becoming larger and more elongate just before pronotal constriction (also arranged in two groups and separated medially). Between second group of longer setae and base only minute setae present. Two nearly straight lines of extremely enlarged clavate setae present on sides of pronotum and covering posterolateral angles. These setae becoming much smaller in anterior fourth of pronotum and expanding outwards reaching anterolateral angles. Lateral area between anterior and posterior angles of pronotum very minutely setose. Underside of anterolateral angles also with large elongate-clavate scales. Hypomeron flangelike, with short and shallow emargination opposite to eye (to receive canthus separating compound eye) provided with some very long and few shorter setae. Antennal pocket deep. Scutellar shield triangular, pointed apically. Elytra rather slender cylindrical, maximum width across median third, opaque and convex dorsally, with prominent rounded humeri. Large hump near apex on each elytron, provided with obtuse glossy glabrous notch at base. Tracks of two longitudinal carinae on each elytron additionally to glabrous glossy and almost complete juxtasutural carina. Punctures deep, of irregular oblong shape, irregular in size (Fig. 294). Intervening spaces subopaque, in part covered with microscopical velvety pubescence. Dorsal setae scale-like. Generally, tiny to very large seta rising from anterior margin of each puncture. Longer setae elongate clavate and sparse, minute setae elongate ovoid, not surpassing length of corresponding punctures. Epipleuron densely covered by rather small clavate scales. Male pygidium densely and deeply punctured, except for margins covered with large strongly clavate setae all pointing obliquely to middle (Fig. 460); intervening spaces subopaque. Anterior margin with minor scale-like setae not surpassing length of corresponding punctures. Along distal margin with longer and stronger elongate clavate setae. Abdominal ventrites much less coarse punctured than dorsum, laterally with small scale-like clavate setae. Abdominal ventrites with no track of lateral longitudinal ridge. Legs long and slender, femora and tibiae covered with minute scale-like setae. Protibia straight, meso- and metatibia stouter than protibiae and gradually thickened distally, on inner margin each provided with row of ordinary setae. Protibia with track of inconspicuous and interrupted carina on dorsal surface. Two teeth on external margin of male protibia: one pointed distal and other broad obtuse inconspicuous basal short distance from distal one (Fig. 366). Tibial spurs not paired, those of pro- and mesotibiae strongly curved. Tarsal claws strong, strongly curved, provided with large pulvilli (in males only?). Spiculum gastrale as in Fig. 568. Male aedeagus as in Figs 586–588.
Sexual dimorphism
Female is unknown.
Ecology
Occurs in primary lowland rainforests at ~ 250–359 m altitude. Possible diurnal.
Distribution
Hitherto only known from the southern foothills of the Star Mountains, Central Cordillera of New Guinea.
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 29-30, DOI: 10.5852/ejt.2020.721.1127, http://zenodo.org/record/4122118