Bryotropha similis Stainton 1854

Bryotropha similis (Stainton, 1854)

(figs. 1, 2, 9, 10, 19, 26, 27, 39, 40, 47, 57–60, 77)

Gelechia similis Stainton, 1854: 115.

Gelechia thuleella Zeller (in Staudinger), 1857: 276.

Gelechia similiella Doubleday, 1859: 30.

Gelechia pullifimbriella Clemens, 1862: 120. Holotype ♂(?), “181” or “191” (on handwritten label), USA, “ type ANSP 7351” [ANSP]. Syn. n.

Gelechia confinis Stainton, 1871: 98.

Gelechia obscurecinerea Nolcken, 1871: 573.

Gelechia stolidella Morris, 1872: pl.108, fig. 1.

Bryotropha fuliginosella Snellen, 1882: 645.

Duvita (?) tahavusella Forbes, 1922: 103. Holotype ♂, USA: Uphill Brook, Mt. Marcy trail, N.Y., 10.VII. ’18, Alt. 3200 ft, W.T.M. Forbes, Collector, CUIC, type No. 519 (examined). Syn. n.

Gelechia clandestina Meyrick, 1923: 19. Lectotype ♂ (published by Clarke, 1969: [381]): “Toronto, Canada, Parish, 6.12; Lectotype Gelechia clandestina Meyrick, J.F.G.C. 1947; Gelechia clandestina Meyr.; ♂ genitalia on slide 22.ix.1947, J.F.G.C. 5775” (BMNH) (examined). Syn. n.

Diagnosis. Small blackish species with indistinct wing markings and the inside of the labial palpus white, speckled fuscous.

Description. Adult (figs. 2, 9, 10, 19). Wingspan 10–12 mm. Labial palpus white, speckled fuscous on the inner side, heavily suffused with fuscous on the outer side, segment 3 darker than segment 2. Antenna fuscous indistinctly ringed with ochre. Head with frons white, speckled fuscous to fuscous; vertex, thorax and tegula concolorous with forewing. Forewing glossy blackish brown; plical and discal stigmata very indistinct, first discal beyond second plical; costal and tornal patches usually whitish and indistinct, often fused to form an irregular or outwardly fascia; subapical area with many blackish scales; cilia dark gray with one or two ciliary lines. Hindwing fuscous, darker toward apex; cilia concolorous.

Variation. The costal and tornal patches vary from rather prominent to absent; very occasionally they are yellowish instead of whitish. Some specimens are slightly lighter with more distinct stigmata while others are plain blackish without visible wing markings. Some specimens from Greenland have the forewing more or less suffused with white scales (fig. 19).

Similar species. B. plantariella, B. hodgesi, q.v.

Male genitalia (figs. 26, 27, 39, 40, 57–60). Uncus subrectangular. Socius with 3–4 setae. Gnathos relatively slender with a sharp 120 degree, distinctly thickened just after bend. Thornshield triangular with 50–80 spikes of different sizes. Margin of vinculum bent near halfway (figs. 39, 40).

The most important characters are the shape of the gnathos and that of the vinculum. The typical gnathos (fig. 57) is unmistakable, but it occasionally displays a much more gradual bend and may even lack a clear local thickening (fig. 60) thus resembling the gnathos of B. hodgesi and B. branella. The vinculum of B. similis is distinctly smaller than in B. hodgesi, B. branella and B. altitudophila and is bent slightly before halfway whereas in the other three species the vinculum is bent at one­third or even before (see arrowheads in figs. 39–43). A further subtle difference is observed in the aedeagus, which in B. hodgesi, B. branella and B. altitudophila has a stronger curve and is somewhat larger than in B. similis.

Female genitalia (fig. 47). Segment VIII ventrally with crescent­shaped lamella postvaginalis and microtrichia and a clearly marked semicircular invagination up to about 1/4. Distal end of the ventral groove marked by a heavily sclerotized extension. Dorsal side of segment VIII with a clear median tongue. Signum large, elongate rectangular to oval, with stout spikes on the corners. Not to be confused with any other North American species.

Biology. Larva with head and prothoracic plate dark brown, body brown (Meyrick, 1928: 623). In Europe (England) larvae have been collected from old walls covered with mosses (Stainton, 1871: 99). Adults fly from early June to late August, most likely in one generation. In the northern part of its range similis is widespread in lowland regions, toward the south this species becomes restricted to higher altitudes to 3100 m. This preference for temperate and Nordic climates is also observed in the Palaeractic (Karsholt & Rutten, in press).

Distribution (fig. 77). Widely distributed in Canada and the USA. One of the few gelechiid moths that also occurs in Greenland. Widely distributed and often very common throughout the Palaearctic.

Material examined: 484 ɗ, 180 Ψ, 4 ex, including 57 male and 30 female genitalia preparations.

Remarks. Gelechia pullifimbriella Clemens was described from an unstated number of specimens from an unstated locality. A syntype labeled “ type ANSP 7351” is in the Academy of Natural Sciences, Philadelphia. It is badly damaged, missing the left pair of wings and the abdomen. Though we did not study the specimen itself, Mr. Jason Weintraub of the ANSP was so kind to provide us with a photograph of the type. This revealed a nearly unicolorous fuscous forewing and a dark hindwing. In the Nearctic this combination of features is only found in B. similis; dark forms of B. hodgesi have a much paler hindwing, and B. plantariella has a different wing shape and more distinct stigmata. The same conclusion had been reached by R. W. Hodges (in litt.) who studied the type of B. pullifimbriella in the past.

Duvita tahavusella was described from five specimens from Adirondacks, New York; the holotype collected on 10 July 1918 in Uphill Brook, Mt. Marcy Trail 3200 ft, and 4 paratypes collected on 8 and 10 June 1916 in Peru (also Adirondacks). External features and genitalia do not differ from those of B. similis.

Gelechia clandestina was described from 14 specimens collected in June and July by Parish at Lake Muskoka, Parry Sound, Canada (Meyrick 1923: 19). The external features as well as the genitalia are characteristic of those of B. similis.

B. similis was first reported from the Nearctic region by Wolff (1964: 44), who recorded it from Greenland and Newfoundland.