Bucculatrix improvisa Braun 1963

Bucculatrix improvisa new species (Figs200, 200a, 201.)
Face pale straw-colored, tuft pale ocherous, usually brown centrally ; eyecaps pale straw-colored, with a few brownish speckles, antennal stalk conspicuously annulate with dark brown. Thorax and fore wings golden brown or ocherous, the scales mostly tipped with dark brown, sometimes very narrowly ; the immediate base of wing paler ; a streak along fold sometimes orange-tinted ; at basal fourth, and separated from the costal margin by brown-tipped scales, is
a pale roundish spot nearly reaching the fold, this spot often more or less dusted with brown-tipped scales of the ground color, and sometimes obliterated ; just before middle of costa, an oblique pale streak; at two-thirds of costa, a second but narrower oblique pale streak, which may meet, at a very obtuse angle or even lie in line with, a faint pale spot or streak at tomus ; between these two costal streaks the ground color is darkened ; a pale spot precedes an irregular group of black-tipped scales at apex, some of which project irregularly into the cilia and may touch a line of black-tipped scales opposite apex; on middle of dorsum, a large patch of black or dark brown-tipped raised scales, with an illdefined pale patch basad of it ; between the raised scales and the pale streak at tornus, the ground color is darkened, the scales sometimes broadly brownor blackish-tipped; the area beyond the pale tornal streak is usually of a more uniform golden ocherous color, and the slender scales projecting from it into the cilia of termen are pale brown-tipped, the outer line of these scales meeting the line of black-tipped scales opposite apex with a strong contrast. Hind wings and cilia fuscous, in the male the apex of the wing considerably darker and somewhat irrorated. Legs grayish straw-colored, the tarsal segments darker at tips. Abdomen dark fuscous above, pale beneath.
Alar expanse 7 to 7.5 mm.
Male genitalia (fig. 201). Harpes typical of the section, but very slender and parallel-sided, rounded at apices ; socii bent inwardly, thus appearing narrow and acute, when flattened, broad and rounded; aedeagus elongate, tapering to the acuminate apex ; vinculum a very narrow band, posteriorly curving midventrally. Scale sac large, nearly globular.
Female genitalia (figs. 200, 200a). Fringing specialized scales of posterior margins of segment 7 short, only half as long as the normal scales overlying them ; on each side of ostium on sternite of 8, a large patch of specialized scales, made up of innumerable small, pointed, heavily pigmented scales; at anterior margin of tergite of 8, a long double row of minute specialized scales ; margins of ostium outcurved ; bursa copulatrix very small, signum occupying one-half its length, ribs closely placed, each becoming attenuated and ending in a series of minute spines and knobs (fig. 200a).
Type. — $ , Fort Ancient State Memorial, Warren County, Ohio, rearing record B.2284 (larva on Tilia americana L.), imago in early July (A. F. Braun) [A.F.B.Coll.].
Allotype. — 2, same data as the type.
Paratypes. — 3 <$, 3 2, same data as the type; 1 $ , imago July 9.
Food plant, Tilia americana L. ; rarely mines occur on Tilia neglecta Spach and on T. heterophylla Vent.
The egg is laid on the upper side of a leaf against a vein ; the mine is a fine thread lying at first alongside the vein for 8-10 mm., then sharply diverging from it for about 2 mm. ; on thin leaves the mine may be 20-25 mm. long', with the section diverging from the vein 4-5 mm. long and sometimes winding. After leaving the mine, the leaf is eaten in patches, leaving the tipper epidermis. Both first and second moulting cocoons white. The fifth instar larva is greenish red, with tubercles white and strongly contrasting. The cocoons of the early summer generation, spun by larvae becoming full-fed in mid-June, are to be found on the underside (sometimes on the upper side) of leaves of the food plant ; they are usually yellowish, anterior and posterior ends bright orange or reddish orange, and sides (in contact with the leaf) narrowly reddish orange, with the reddish color sometimes spreading over the whole anterior section of the cocoon ; occasionally cocoons are of a paler brownish ocherous color; the even, regular ridges are few in number, not over six and sometimes fewer distinct.
Two generations a year ; larvae of the first generation, full-fed in June, produce imagoes in early July; a second generation, with larvae in late August or early September, passes the winter in the pupal state.
Bucculatrix improvise may best be identified by genitalia, which are distinctive in both sexes ; in the male the slender harpes and acuminate aedeagus. in the female the large patches of minute specialized scales on sternite of 8 separate this species from others of the section. In wing markings, the pale spot ( not the usual pale streak common to related species) below costa at one-fourth the wing length, and the pale brown-tipped scales at tornus and termen, sometimes with a ragged effect, may be of some aid in identification. It somewhat resembles pale, lusterless examples of B. trifasciella.

Bucculatrix improvisa is a moth in the family Bucculatricidae. It was described by Annette Frances Braun in 1963 and is found in North America, where it has been recorded from Ohio.

The wingspan is 7-7.5 mm. The forewings are golden brown or ocherous, the scales mostly tipped with dark brown. The hindwings are fuscous. Adults have been recorded on wing in July. There are two generations per year.

The larvae feed on Tilia americana, Tilia neglecta and Tilia heterophylla. They mine the leaves of their host plant. The mine has the form of a fine thread, at first lying alongside the vein, then sharply diverging from it. Older larvae leave the mine and live freely on the leaf, which is eaten in patches, leaving the upper epidermis. Full-grown larvae are greenish red. Pupation takes place in a yellowish cocoon, which is spun on the underside of a leaf. The species overwinters in the pupal stage.