Chlamydastis dominicae Duckworth 1969

Chlamydastis dominicae

Alar expanse 23–25 mm.

Antenna brown flecked with white. Head white suffused with brown; labial palpus mottled brown and white, second segment with basal half exteriorly brown, first segment brown. Thorax white overlayed with brownish orange; legs white patched with brown. Forewing white variously mottled with brown, black, and brownish orange; two outwardly oblique transverse indistinct black lines from costa before middle but failing to reach dorsum: an irregular outwardly oblique blotch of brownish orange from costa at middle extending to area just above tornus; two parallel indistinct subterminal orange lines from apical third, terminating in two black dashes at tornus; terminal line consisting of black dots from well before apex to tornus; cilia gray, lighter basally. Hind wing heavily overcast with gray; cilia whitish, with basal gray line.

MALE GENITALIA.—Unknown.

FEMALE GENITALIA (slide WDD 3613).—Ovipositor lobes large, sclerotized; two parallel inner lobes covered with minute papillae. Lamella postvaginalis densely clothed with small setae on posterior half, lamella antevaginalis small, bandlike. Ostium small, ostium bursae sclerotized; ductus bursae membranous except enlarged sclerotized area at midpoint; corpus bursae membranous, signum small slightly dentate plate constricted in middle, inception of ductus seminalis from posterior portion of sclerotized pouch.

TYPE.—In the United States National Museum, No. 69951.

TYPE-LOCALITY.—.4 mi E of Pont Casse, Dominica, Lesser Antilles.

DISTRIBUTION.—Known only from the type-locality and immediate vicinity.

Described from the female holotype: Dominica: .4 mi E of Pont Casse, V–6–1964, O. S. Flint, Jr.; one female paratype: same data as holotype; one female paratype: Dominica: 2.2 mi E of Pont Casse, V–II–64, O. S. Flint, Jr.; two female paratypes: Dominica: Pont Casse, 2 mi NW, V–18–1965, V–21–1965, D. R. Davis.

This is the only species of stenomid discovered during the intensive collecting conducted in connection with the Bredin-Archbold-Smithsonian Biological Survey of Dominica. Since two of the collectors were microlepidopterists and several others were experienced collectors of Microlepidoptera, it seems reasonable to assume that the possibility of many more species occurring on the island is remote. However, the type-locality of this species (Pont Casse) is reported by the collectors to be wet montane forest at approximately 2,000 feet elevation and representing a relatively undisturbed element of the natural vegetation. Pont Casse was one of the few points that had ready access to this habitat by road and thus the only point at which this type of plant association was sampled intensively for Microlepidoptera. Thus, further collecting might produce additional species of stenomids and certainly should provide male specimens of the species described here.

The information concerning the habitat may also bear on the distribution pattern presented by this species. The presence of a species of Chlamydastis so far up the chain of islands that comprise the Lesser Antilles and the lack of records of this or any other species in the genus from the other islands presents an interesting problem in distribution. Since the nearest point to Dominica where species of Chlamydastis are encountered is Trinidad, which of course is continental in the makeup of its fauna, the question immediately arises, why a species occurs on Dominica and not in between. Two possibilities seem likely at this point. Either (1) the species was at one time more widespread but was restricted by the disappearance of its host plant as the environment was changed by the onslaught of man and his activities, or (2) the species is still present on the other islands and the lack of records is due to inadequate sampling of the wet montane forest that still exists on these islands. I am inclined to favor the latter possibility, since far too little collecting has been done on the other islands to date.

Mothonica Walsingham, 1912, p. 153.

The name Mothonica is currently applied to a group of species that have been assigned to the genus on the basis of their obvious relationship to each other and a superficial resemblance to the type-species, M. periapta Walsingham. Since the type-species was described from a single specimen without an abdomen, it is impossible to determine accurately the availability of the generic name for the species that have been assigned to it due to the inability to examine the genitalia. Forbes (1930) established the precedent for other workers by describing a new species, ocellea, which he assigned to Mothonica apparently on the basis of its resemblance to Walsingham’s figure of the type-species. Busck (1933) transferred ocellea to the heterogeneous Stenoma because it did not agree structurally with Walsingham’s generic description, which lays stress on the stalked veins 8 and 9 in the forewing and the approximate veins 6 and 7 in the hind wing. Subsequent workers (Clarke, 1955; Duckworth, 1964) have continued to place species related to ocellea in the genus Mothonica although ocellea has never been formally returned to the genus. In this paper ocellea Forbes is returned to Mothonica and an additional new species described. Future studies may indicate a different generic affiliation; however, it seems more appropriate to maintain the present assignment for the time being.

Chlamydastis dominicae is a moth of the family Depressariidae. It is found on Dominica.

The wingspan is 23–25 mm. The forewings are white variously mottled with brown, black and brownish orange and there are two outwardly oblique transverse indistinct black lines from the costa before the middle but failing to reach the dorsum. There is an irregular outwardly oblique blotch of brownish orange from the costa at the middle extending to the area just above the tornus. There are two parallel indistinct subterminal orange lines from the apical third, terminating in two black dashes at the tornus. The terminal line consisting of black dots from well before the apex to the tornus. The hindwings are heavily overcast with grey.