Bucculatrix thurberiella Busck 1914

Bucculatrix thurberiella Busck 1914. Bucculatrix thurberiella Busck, Proc. Ent. Soc. Wash. XVI: 30. Type $, genitalia slide 9942, J. F. G. C, allotype 2, genitalia slide 9943, J. F. G. C, Santa Catalina Mountains, Arizona [U.S.N.M., Type No. 16699].
1916. Bucculatrix thurberiella, A Pest of Cotton in the Imperial Valley. McGregor, E. A. Journ. Econ. Ent. 9: 505-510. Plates 36, 37.
1927. Bucculatrix thurberiella Morrill, Journ. Econ. Ent. 20: 536-544.
Face white, tuft white with an occasional grayish hair ; eye-caps white, antennal notch very shallow, stalk with fuscous annulations. Thorax white. Fore wing (fig. 13) white; extreme costal margin from base to beyond middle blackish, the black scales projecting onto the wing near base as a narrow elongate patch, at one-third as a slightly larger and oblique patch, near middle of wing as a conspicuous irregular patch which continues as a fine line (sometimes obsolete) obliquely across the wing to a conspicuous patch of blackish scales on termen which continues along termen in an irregular line to apex; beyond this the cilia are dotted with black-tipped scales; a more even short line of scales in cilia near apex ; cilia on termen immediately below apex often blackish ; apical costal half of wing beyond the oblique streak dusted with paler brown and blackishtipped scales; a few black-tipped scales below fold near base; a group of black scales just within the dorsal margin and on fold is followed by scattered brown scales. Hind wings and cilia pale whitish ocherous. Legs pale whitish ocherous inwardly, blackish fuscous outwardly, hairs of posterior tibiae white, tarsal segments white at base.
Alar expanse 7 to 8 mm., 9 mm. in some of the cotton-feeding specimens.
Male genitalia (figs. 239, 239a, 239b, 239c, 239d, 239e, all figures to the same scale). Both tergite and sternite of segment 8 modified into specialized plates; sternite prolonged into two long slender prongs, the right prong the longer, laterally with two rounded lobes curving dorsad ; the tergite a large flat plate terminating in two black pillars — masses of fused-together setae ; prongs of both sternite and tergite exceeding the genitalia; harpe (fig. 239a) with a stout costal lobe terminating in heavy setae, below tip with three long and several short setae, cucullus with short setae; sacculus produced as a sharp pointed process; socii slender, erect, widely separated ; anellus ovoid ; aedeagus long, gradually tapering ; vinculum an equilateral triangle. Scale sac bilobed, scales slender, forked.
Female genitalia (figs. 240, 240a, 240b). Segment 8 strongly sclerotized except for a narrow posterior band, lateral margins produced anteriorly into curved processes, appearing as rudimentary apophyses ; raised pockets on lateral margins ; two short setae on a dor so-lateral sclerotized surface of the membranous posterior part of segment 8 (fig. 240a) ; ostium flaring, opening at the posterior margin of the sclerotized section of segment 8 ; signum faint, a mass of minute spines on a weakly sclerotized surface (fig. 240b).
Specimens examined. — approximately 125 including the type series on Thurberia thespesioides Gray and large series reared on cotton.
Arizona : Pima Canyon, Santa Catalina Mountains, August and September, 1913, type and allotype, and several paratypes, not all in good condition, all reared on Thurberia thespesioides Gray, together with 8 and 2 genitalia slides from type material by Busck and Clarke; Mesa, 44, 8 , 2, "bred from Pima cotton bolls and leaves," November 1930 to January 1931 (H. C. Young) ; Tucson, 55, 8 , 2, with cocoons, " on cotton " with dates of emergence July and August (L. J. Bottimer) [U.S.N.M.] ; Madera Canyon, 4880 feet, Santa Rita Mountains, 5 8 , 3 2, August 23-27 ( R. W. Hodges) [Cornell U.].
California: Calexico, 8 8 , 2 , July 14-15, 1931, "on cotton," with pressed leaves showing larval work (T. C. Barber) ; same locality, 8, 2 (O. A. Pratt and T. P. Cassidy) [U.S.N.M.].
Texas: San Benito, 1 $, 1 2, April 1-7 [U.S.N.M.]; 1 8,1 2 , u on cotton," 7.VIII.35 [C.N.Coll.].
In addition to the above records, five specimens in the United States National Museum from South America labeled " Lima " are identified (AB) as B. thurberiella.
The pressed cotton leaves show a short linear mine and eaten patches. Busck (I.e.) gives the following description of the larva and cocoon on Thurberia: " The larva is dirty white, rough skinned, with prominent white tubercles and with two dorsal rows of black dots, one on each segment. Head light ochreous with black eye spots and reddish brown month parts.
" Cocoon ribbed, typical of the genus, pearly white, length 8-9 mm." The cocoon is slender with eight to ten ridges, not always welldefined.
Specimens reared on cotton often surpass in wing expanse the moths of the type series, but, as shown by genitalia, are identical with those reared on the native food plant, Thurberia thespesioides Gray. The only species which B. thurberiella resembles in markings is the Mexican B. gossypiella Morrill, from which it is easily separated by genitalia of both sexes; B. thurberiella is further distinguished from B. gossypiella by the erect ridged egg and the linear serpentine mine in the leaves or bolls.
McGregor (I.e.) notes that the cocoon is surrounded by a "palisade." He raises the question as to whether Thurberia is the original food plant and suggests that " the insect has found its way to the United States from the ancient cotton-growing areas of Mexico and from the insular and maritime regions of tropical America to which cotton is indigenous." It should perhaps be noted that Thurberia thespesioides Gray is, by some authors, included in Gossyphim as Gossypium thurberi Todaro. 188

Bucculatrix thurberiella, the cotton leaf perforator, is a species of moth of the family Bucculatricidae. It was first described by August Busck in 1914. It is native to the south-western United States and northern Mexico. It is an introduced species in Hawaii.

The wingspan is 7–9 mm. The forewings are white, but the extreme costal margin from the base to beyond the middle is blackish. The hindwings are pale whitish ocherous. In the virgin females of Bucculatrix thruberiella the bursa copulatrix occupies approximately 0.7 mm3.

The larvae feed on Gossypium tomentosum and Thurberia thespesioides. They mine the leaves of their host plant. The mine is mainly on the upper surface and progresses tortuously, ever widening. When the first instar is about completed an exit hole is cut through the upper epidermis and the larva leaves the inner tissue. When the feeding activities of this stage are finished the larva weaves a tiny circular web over some slight depression on the underside of the leaf. Second- and third-instar larvae feed on either the upper or the under surface.