Trigonops incrinita, Zimmerman, 1942

Zimmerman, Elwood C., 1942, Curculionidae of Guam, Insects of Guam I, Honolulu, Hawaii: Bernice P. Bishop Museum, pp. 73-146 : 89-90

7. Trigonops incrinita , new species (pl. 1, C).

Derm dark reddish brown to black; scaling basically white or grayish white, normally almost entirely concolorous, but when abraded appearing blotched or tessellated with small to large black areas; elytra usually with a vague post-median V of denser scaling.

Head with the front densely squamose, scaling concealing puncturation which is evidently fine and shallow, setae inconspicuous; eyes rather flatly convex, not strongly interrupting longitudinal lateral cephalic outline, as long or slightly longer than narrowest interocular breadth. Rostrum with area between transrostral carina and basal suture slightly to distinctly convex longitudinally, either distinctly impressed below level of carina or continuous in outline with apical part of rostrum, with a fine median carina, about three fourths to almost as long between the carina and basal suture as the interocular breadth; apical declivitous part densely but not coarsely punctate, with numerous scales at base and scattered scales distally. Antennae with scape densely squamose, closely set with decumbent setae, the tips of most of which touch derm, longer than funicle to slightly longer than funicle plus first segment of club; funicle with lengths of segments as follows: (1, 1.4) (2, 1.3) (3, 1.1) (4, 1.0) (5, 0.9) (6, 0.8) (7, 0.7); club rather stoutly oval, slightly shorter than preceding three funicular segments. Prothorax as long as broad, broadest at or slightly behind middle, subequally narrowed toward base and apex, disk gently convex sometimes just perceptibly flattened along middle in basal half; discal punctures comparatively rather small, separated by interstices about as broad or broader than their diameters, concealed by dense scaling, scales angular and forming a reticulate pattern, some of discal interstices bearing small, low tubercles; setae few, small, hardly discernible. Elytra three fourths as broad as long, twice as long as prothorax, broadly rounded on sides from subtruncate or concave base to about apical third, thence sharply narrowed to apex, broadest before middle; discal striae shallow, almost concealed by scaling in some places, distinctly deeper on lateral declivities, their discal punctures rather deep, striae often not impressed between them, some near the base sometimes with low tubercles at their bases; discal intervals quite flat, scaling very dense, almost imbricated, scales mostly angular, flat, appearing rather dull because of their minute reticulation, without discal setae, with only a few setae on declivity. Legs with hind femora reaching to or behind middle of fifth ventrite, broadest part of club slightly more than twice as broad as base and at five eighths of distance between base and apex, densely squamose, setae closely appressed to derm and not slanting or erect; hind tibiae almost straight on outer side from base to apical expansion, densely squamose, setae decumbent or but slightly slanting away from derm. Stermtm with prosternum about one half as long from anterior margin to fore edge of coxal cavity as distance between hind margin and cavity, intercoxal process one fourth to one third as broad as a coxa, densely squamose, densely punctate; mesosternum densely squamose excepting a small bare area just above coxa; metasternum one third to one half as long between mid and hind coxae as breadth of a mesocoxa, densely squamose from inner margins of coxae outward, less densely toward middle, rather closely punctate, setae decumbent. Venter with first ventrite free from scales in middle, densely clothed laterally, punctures separated by interstices about as broad as their di~meters, setae rather long, decumbent; second ventrite sculptured and setose as the first, but with denser scaling medially; third and fourth ventrites sculptured and evidently setose for their entire breadths; ventrite 5 coarsely and densely punctate, densely setose, most of setae decumbent, but with some long erect setae near apex, with only a few scattered scales. Length, 4.5-5.0 mm.; breadth, 2.5-3.0 mm.

Holotype, sex not certain, Guam, from Hibiscus tiliaceus, Sept. 17, 1937, Oakley, numbers 135 and 37-26161 (in U. S. Nat. Museum); and two abraded paratypes, labeled " Island Guam ", Fullaway.

This species is closely allied to T. vulgaris and T. convexa , but can be separated from. those species, as well as all of the other Guam species, by the absence of discal setae on the elytra.