Tytthoxydema exilis, Zimmerman, 1942

Zimmerman, Elwood C., 1942, Curculionidae of Guam, Insects of Guam I, Honolulu, Hawaii: Bernice P. Bishop Museum, pp. 73-146 : 128-129

34. Tytthoxydema exilis , new species (pl. 5, I).

Derm piceous, moderately shiny; dorsal setae pale, inconspicuous.

Head as long as broad, distinctly constricted on sides behind eyes, constriction only slightly, shallowly and broadly interrupting dorsal outline, but not impressed as a suture across dorsum, longitudinal dorsal outline of crown and front sinuous, constriction, when measured from above, length of an eye behind eyes, three fifths to three fourths length of an eye behind eyes on sides; area behind constriction impunctate or with a few, scattered, minute, hardly discernible punctures, area beyond constriction, and interocular area, densely and evenly punctate, punctures not large, individually distinct and usually separated by interstices about as broad as punctures, punctures bearing minute, specklike setae; interocular area slightly less than three times as broad as an eye as viewed from front; eyes separated by about one and one half times length of an eye from prothorax on sides. Rostrnm, measured from side, as long as head, two fifths as long as prothorax; emarginate on sides between eyes and antennae, thence rather strongly expanded and rather straight-sided to near apex, broadest apical breadth about one third narrower than narrowest basal breadth in male, less strongly expanded in female; puncturation finer and much less distinct than that of interocular area, dull and coarsely reticulate in male, shiny in female; antennae inserted at about basal fourth at about half the breadth of an e);e in front of eyes; scrobes passing rapidly down to lower anterior edge of eyes, but not continued much past fore margins of eyes. Antennae with scape reaching slightly, but distinctly behind posterior margin of eye to a point about half way between eye and cephalic constriction; first funicular segment stout, subconical, about as long -as 2 plus 3, 2 hardly longer than 3, 3 to 5 moniliform and subequal; club slightly longer than four preceding segments. Prothorax slightly to more than one sixth longer than broad, broadest near basal third, base slightly constricted, thence arcuately narrowing to distinct, welldefined, subapical constriction which hardly interrupts the almost straight longitudinal dorsal contour; dorsal puncturation rather similar to that on front of head, punctures rather small, dense, even, individually distinct, separated by interstices equal to about breadths of punctures, and bearing specklike setae. Elytra somewhat more than twice as long as broad (6:2.25), more than twice as long as prothorax in the same proportions; striae well marked but not coarse, narrower than intervals, their punctures rounded or quadrate, coarser toward base and there often as broad or broader than intervals, each puncture bearing a flecklike seta, tenth stria approximated by ninth above metacoxa but evidently continued to apex; intervals flat or but slightly convex, at most very minutely punctate, and bearing hardly discernible setae, the ninth interval hardly swollen at its junction with third interval, hardly curved upward at apex and there about twice breadth of third interval from apex. Legs with tibiae rather evenly expanded from base to apex, base of hind pair about half as broad as apex, unci long, slender, well developed, tooth at inner apical angle well developed, slender and sharp; tarsi with third segment slightly broader than second, truncate apically below, not bilobed, fourth segment almost as long as three preceding segments together. Stcrmmi with prosternum broadly impressed in middle in front of coxae, not quite twice as long in front of coxae as behind coxae, intercoxal process slightly narrower than breadth of a coxa, densely pµnctate, more coarsely so in front of coxae, punctures not tending to be laterally confluent; mesosternum on same plane as metasternum, intercoxal process punctate, not quite twice as broad as a mesocoxa; metasternum densely punctate, punctures rather similar to those on pronotum, but slightly larger and individually more distinct, distance between mid and hind coxae three times as long as breadth of a mesocoxa, metacoxae separated by slightly more than breadth of a mesocoxa. Venter with first two ventrites with similar or somewhat less dense puncturation than metasternum, first impressed down middle in male, tumid in female; ventrites 2 and 3 with a row of punctures at their bases only; ventrite 5 transversely impressed before apex, finely punctate, coarsely reticulate, setose behind. Length, 1.75-2.25 mm.; breadth, 0.5-0.6 mm.

Holotype male in National Museum, allotype female in Bishop Museum , 14 paratypes and two broken specimens collected from under bark of a dead tree, Sept. 1937, Oakley , nos. 143 and 37-2615.