Bucculatrix tenebricosa Braun 1925

Bucculatrix tenebricosa Braun (Figs. 91, 92.)
1925. Bucculatrix tenebricosa Braun, Trans. Amer. Ent. Soc. LI: 220. Type $, near Logan, Cache County, Utah [A.F.B.Coll.].
Head and tuft white ; antennal stalk white with broad dark gray annulations. Thorax white. Fore wings white, with scattered pale brownish-tipped scales and clusters of dark brown-tipped scales, which form ill-defined markings; a cluster of a few of these scales before middle of costa, a larger such cluster beyond middle of costa, and a small patch of raised dark scales below fold ; darktipped scales extend along the base of the costal cilia and around apex to tornus, forming at the apex a scattered patch ; a line of black-tipped scales crosses the cilia opposite apex and continues as an irregular line to tornus. Hind wings silvery gray with white cilia. Legs white, tibiae and tarsi of the fore and middle legs broadly banded with gray, hind tarsal segments only banded with gray. Abdomen pale gray.
Alar expanse 7 mm.
Male genitalia (fig. 92). Harpes slender, tapering rapidly to the very narrow cylindrical apical third, heavy setae at apex; socii widely separated, elongate, three times as long as broad, very thin membranous, fine setose ; anellus a tapering cone; aedeagus broad at base, tapering, appearing as if jointed, the outer portion slender and curved, arising from a depression in the broader basal portion ; vinculum a broad band. Scale sac elongate pear-shaped.
Female genitalia (fig. 91). Ovipositor lobes short; ostium opening into a deep furrow, its sclerotized sides curving outward ; produced lateral lobes of segment 7 with curved specialized scales ; a cluster of scale sockets at anterior lateral margin of segment 8 indicates the probable presence of a tuft of specialized scales (lost on the slide); ductus bursae slender throughout; signum a transversely placed ring, signum ribs with long slender spines.
Specimens examined. — 2 $, 1 ?.
Utah : near Logan, Cache County, $ type, 1 $ , 1 5 paratype, June 25, 1924, flying amongst rabbit brush, Chrysothamnus graveolens (Nutt. ) Greene, (A. F. Braun) [A.F.B.Coll.].
Known only from the three specimens of the type series. Food plant and early stages unknown.
By genitalia, B. tenebricosa is closely allied to eurotiella Wlsm. In the male, it differs from eurotiella by the very broad base of aedeagus, and the longer, slender socii ; in the female, by the broad short ovipositor lobes, and especially by the very different signum, a transverse ring in tenebricosa, an elongate, longitudinally placed ellipse in eurotiella. The moths are distinct in general appearance, although the ill-defined wing markings of tenebricosa are situated as in eurotiella.

Bucculatrix tenebricosa is a moth in the family Bucculatricidae. It is found in North America, where it has been recorded from Utah. The species was described by Annette Frances Braun in 1925.