Eutornus nigriceps Zimmerman 1942, new species
Creators: name: Zimmerman, Elwood C.
Publisher: name: Zenodo
Year: 1942
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Curculionidae
Eutornus
Eutornus nigriceps

description: 42. Eutornus nigriceps, new species (pl. 5, <i>H).</i> Derm rather shiny above, reddish brown with head and rostrum mostly black, rostrum more diluted with red, apex of prothorax dark, elytra clouded with black in caudal fourth. <i>Head</i> one fourth broader across eyes than the length of median line from pronotum to anterior margins of eyes; minutely punctate, punctures separated by interstices as broad or much broader than their diameters and each puncture bearing a minute, specklike seta; with a feeble, elongate interocular impression; slightly and inconspicuously constricted on sides at about half the length of an eye behind eyes, constriction not impressed across dorsum, longitudinal dorsal contour evenly and continuously arcuate with front and rostrum; interocular area three times the breadth of an eye as measured from above. <i>Rostrum</i> as long from front of eyes to apex as head from prothorax to front of eyes, less than half as long as pronotum, hardly longer than its basal breadth; sides almost straight and subparallel, but slightly broader beyond antennae than before; puncturation similar to that on head, but somewhat denser; epistome conspicuously emarginate and bidentate apically; inner lobe of gena projecting into a sharp point; antennae inserted at basal third at almost length of an eye in front of eyes; lower edge of scrobe reaching venter of rostrum on line with fore edge of eye, upper edge touching eye. <i>Antennae</i> with scape rather strongly bent upward at about middle to curve around lower edge of eye, one third broader beyond middle than at base, reaching to slightly in back of eye to cephalic constriction; funicle with first segment about as long as 2 plus 3 plus 4, hatchet shaped, 2 to <i>7</i> subequal in length, but each successively slightly broader; club compressed, as broad as long, about as,, long as six preceding segments. <i>Prothorax</i> not quite one fourth longer than broad (~-8: 3.2), base slightly sinuous, apex shallowly concave in middle, roundly expanded on sides from base to basal fourth, broadest at basal fourth, thence very slightly arcuately, almost straightly narrowed to strongly impressed subapical constriction at length of an antenna! club from apex, apical part collar-like, constriction narrowly and slightly impressed across otherwise evenly and slightly longitudinally arcuate dorsal contour; derm shiny, punctures small, separated by interstices as broad or slightly broader than their diameters, their setae minute and specklike. <i>Elytra</i> two and one fourth times as long as broad, slightly more than two and one half times as long as prothorax; base emarginate at scutellum; subparallel-sided to apical fourth, thence broadly rounded to apex, without an obvious subapical constriction, apices conjointly emarginate; striae distinctly narrower than intervals, their punctures broader than grooves, comparatively shallow, lateral stria distinct and complete throughout; intervals flat or but slightly convex, each with a row of small punctures bearing microscopical setae, 1 one third narrower than 2 at middle, 9 becoming narrowly elevated and rather sharply cariniform above first ventrite, broader and costiform beyond third ventrite, joining 3 at about breadth of 2 from apex. <i>Legs</i> with femora stout, fore pair about half as broad as long, minutely punctate; tibiae strongly uncinate and mucronate, fore pair angulate on lower edge at slightly beyond middle, posterior face produced into a distinct conspicuous tooth at apical third; tarsi with third segment about one fourth broader than second, shallowly concave at the apex, claws slender, only slightly divergent. <i>Sternmn</i> with prosternum broadly depressed down middle, closely set with small shallow punctures, three times as long before as behind coxae, intercoxal process slightly narrower than breadth of a coxa; mesosternum on same plane as metasternum, punctures shallow and separated by about their diameters, one fifth broader between coxae than breadth of a coxa; metasternum shallowly impressed on sides; punctures similar to or somewhat larger and deeper than those of mesosternum, two and one half times as long, between mid and hind coxae as breadth of intercoxal process of mesosternum, metacoxae separated about as widely as mesocoxae. <i>Venter</i> with first two ventrites with small punctures separated by one and one half or more times their diameters; ventrites 3 and 4 with their bases crenulated with punctures, their disks with a few minute punctures; ventrite 5 with coarser and denser punctures. Length, 3.1 mm.; breadth, 0.95 mm. Holotype, evidently a female, Piti, from a rotten bamboo stump, Aug. 19, 1936, Swezey. (Since this was written I have seen another specimen collected at Piti by Oakley; it is 4.5 mm. in length.)) Sir Guy Marshall kindly compared this species with the British Museum material and says that it is closely allied to but much smaller than <i>E. ferrugineus</i> Wollaston, 1873 from the Papuan area. It cannot be confused with the three Philippine species described by Heller in 1913, because of its size, coloration, structure of rostrum, antenna! scape and other characters. The tooth on the posterior face of the fore tibiae above the articulation of the tarsus is peculiar.
description: Published as part of <i>Zimmerman, Elwood C., 1942, Curculionidae of Guam, pp. 73-146 in Insects of Guam I, Honolulu, Hawaii :Bernice P. Bishop Museum</i> on pages 139-141, DOI: 10.5281/zenodo.5159964