Protrachyasmus Setliff, 2021

Setliff, Gregory, Pancini, Lorenzo & Bramanti, Andrea, 2021, Review of Eudyasmus, with descriptions of a new species from Waigeo Island, Indonesia, and a closely related new genus (Coleoptera: Curculionidae, Molytinae, Eudyasmini), Fragmenta entomologica 53 (2), pp. 377-390 : 385-387

Protrachyasmus Setliff gen. nov.

Type Species. Eudysamus planidorsis Heller, 1908 , here designated.

Diagnosis. Protrachyasmus gen. nov. is included in the tribe Eudyasmini with the other crowned weevil genera (see discussion above). In the key to the crowned weevil genera provided in Setliff (2012: 32), it will key out to 2’ ( Eudyasmus ). The new genus shares a close phylogenetic relation with Eudysamus (see Setliff 2012) but can be distinguished from that genus by the combination of characters presented in Table 1.

Description. Body elongate oval; TL 9.0–12.0 mm, EW 3.6–4.8 mm. Pronotum and elytra subequal in width; humeri not produced. Integument reddish-brown to dark brown. Vestiture composed of very small, patchy, appressed, yellowish-brown, translucent scales, some of which are iridescent green along edges under high magnification and non-iridescent scales including small, flocculent, background scales and longer, suberect, yellowish-brown to white, hair-like scales. Even longer and finer hair-like scales, also pale in color, are usually present on prorostrum, venter, and legs. Head visible in dorsal view; eyes large, finely faceted, not protruding beyond curvature of head, sub-rounded with posteroventral margin linear, interocular distance narrower than subbasal width of rostrum. Male rostrum weakly compressed and arcuate, longer than pronotum; prorostrum with short medial carinae terminating in a small bulb-like protrusion near base, either side of carinae weakly sulcate to metarostrum creating an inverted V-shaped elevation bearing the aforementioned carina; prorostrum and metarostrum smooth in females, finely punctate, lacking carina and basal bulb-like protrusion. Antennae inserted beyond middle of rostrum in males, near middle in females. Scape longer than funicle in both sexes; longer than funicle plus basal segment of club in males. Pronotum bell-shaped in dorsal view; disk densely punctate, punctures large, crowded, irregularly spaced and coalescent; interspaces between punctures elevated, coarsely rugose; with a thin medial longitudinal carinae from apical margin to at least middle of pronotal disk, often reaching pronotal base. Postocular lobes well developed with row of short vibrissae. Prosternal canal a shallow trough with sides nearly obliterate; mesoventral receptacle obsolescent, lacking long hair-like scales ( Fig. 13b ). Pro-, meso-, and metacoxal cavities and metaventrite as in Eudysamus. Scutellum small, circular, lacking scales. Elytra in dorsal view with sides indented at apical third then tapering to declivity, more abruptly tapering from declivity to apex; with ten visible striae, tenth greatly reduced after basal third but is still traceably to apex. Interval three coarsely granulate, slightly raised above adjacent intervals in lateral view; intervals 5–8 slightly produced at declivity forming pair of weak elytral calli. Metathoracic wings fully developed ( Fig. 6 ). Sclerolepidia not observed. Legs thin and very long, hind femur capable of exceeding elytral apex by more than half its length, mesofemur capable of exceeding elytral apex. All femora with single, small, subapical denticle on ventral margin. Tibia weakly compressed basally; protibia sinuate with dorsal edge emarginate at middle, apical third strongly bent ventrad; uncus and premucro well developed; lacking supra-uncal projection ( Fig. 12c ). Tarsomere 1 elongate, 1.5–1.6 times longer than tarsomeres 2 and 3 combined; flattened; tarsomere 2 trapezoidal, flattened; tarsomere 3 deeply bilobed; claws simple, free. Ventrite 1 punctate, weakly distended, on slightly lower plane in lateral view than ventrites 2–5, about as long as remaining ventrites combined, intercoxal process broad; ventrites 2–4 glabrous and impunctate, ventrite 5 punctate. Male and female genitalia are of the Eudyasmus type (see Figs. 4–5 ) and do not differ in any significant way from this or any other genus in the crowned weevil group. See Setliff (2012) for a discussion of conserved genitalia among the crowned weevil genera.

Distribution. PAPUA NEW GUINEA ( Fig. 1 ).

Etymology. The genus name is derived from the combination of the Greek prefix pro- (in this case loosely ref- erencing the pronotum) and adjective trachy- (meaning rough) with -asmus (meant here to show this genus’ close affinity with Eudyasmus ). The gender is masculine.

The specimen that Heller (1908) intended to be the holotype is ambiguous as two specimens bear red type labels. We have selected the female specimen labeled “Typus” to be the lectotype and the male specimen labled “Cotypus” to be the paralectotype.

Paralectotype. 1♂, Cotypus! (on red card) // Br. N. Guinea / Aroa Fl. / E.Weiske // 14539 // PARALECTOTYPE / Eudyasmus planidorsis Heller (handwritten on blue card) ( SMTD) .

Other Specimens Examined. Papua New Guinea: 1♀, 1♂, PAPUA N GUINEA / Manki L.A., Bulolo / Castanopisis log / 16.XI.83 // J. Dobunaba Coll. / 2240 / C.I.E.A. 15819 // Pres by / Comm Inst Ent / B.M. 1984-1 ( BMNH) ; 1♂, PAPUA NEW GUINEA / Morobe Province / Wau, Mt. Missim / 24 May 1984 2000m. / Coll. Chen Young ( CMNH) .

Figures

Fig. 13 – Detail of pro- and mesothorax, ventral view (PSC = prosternal canal, MVR = mesoventral receptacle) – a, Eudyasmus albertisii Pascoe, male; b, Protrachyasmus planidorsis (Heller, 1908) comb. nov., male.

Fig. 6 – Eudyasmus basalis sp. nov., Metathoracic wing.

Fig. 12 – Prothoracic leg details; a, Eudyasmus albertisii Pascoe, 1885, female (PM = premucro, U = uncus, SUP = supra-uncal projection); b, same, male; c, Protrachyasmus planidorsis (Heller, 1908) comb. nov., male.

Fig. 4 – Eudyasmus basalis sp. nov. Male genitalia; a, Penis, lateral view; b, Penis, ventral view; c, Penis, apex in dorsal view; d, Spiculum gastrale; e, Tegmen; f, Tergite VII.

Fig. 5 – Eudyasmus basalis sp. nov., Female genitalia; a, sternite VIII; b, spermatheca, lateral view; c, hemisternites; d, tergite VII; e, tergite VIII.

Fig. 1 – Distribution of the species of Eudyasmus Pascoe, 1885 and Protrachyasmus Setliff gen. nov. Filled in symbols = type locality. Base map from MapCreator 3.0.