Archithosia Birket-Smith, 1965

Genus Archithosia Birket-Smith, 1965 View in CoL

Archithosia Birket-Smith, 1965 View in CoL , A revision of the West African Eilemic moths, based on the male genitalia: 11 (Type species: Lithosia costimacula Mabille, 1878 View in CoL , by original designation).

Remarks. (1) Species of the genus are variable in their size, forewing shape and ground colour (varying from ochreous to greyish-brown) as well as the degree of the transverse line expression, which is in most specimens represented by two spots on the costal margin and the anal vein but can also be continuous. Dark specimens are externally very similar to members of the genus Acanthosia and even the clarification of their generic placement in many cases requires the examination of the genitalia structures, which are clearly different in the two genera. The male genital capsule is very uniform within Archithosia and the main diagnostic characters are found in the vesica configuration while in the female genitalia, the shape and size of the sclerotised posterior section of the corpus bursae are diagnostic. (2) The genus comprises several species with partly overlapping ranges, which, along with the high individual polymorphism, requires dissection of all specimens examined for accurate identification, while the reliable matching of males and females is possible only with molecular methods or breeding experiments. For these reasons, the taxonomy of Archithosia is problematic as the neotype of its type species is a female ( Birket-Smith 1965), and an integrative revision of the genus will be published later in a separate paper (Volynkin, in prep.).

Diagnosis. Species of Archithosia ( Figs 1, 2 View Figures 1–15 ) are medium-sized moths with forewing ground colour varying from ochreous yellow to brown and the forewing pattern expressed as two dark spots on the costal margin and anal vein postmedially, which are in certain species enclosed in an angled transverse fascia. The genital structures of Archithosia are characterised by the combination of the following features. Male ( Fig. 89 View Figures 89–93 ). (1) The uncus is short and cylindrical (similar to Asbolopsyche and Macrodicella whereas it is proximally swollen in Acanthosia and most Architesma ). (2) The scaphium is string-like and gelatinous with only the basal section weakly sclerotised (it is fully sclerotised in other similar genera). (3) The tegumen is downcurved, its arms are anteriorly strongly dilated and fused in their anterior two-thirds (similar to Acanthosia with its arms of the tegumen fused in their anterior half whereas in Asbolopsyche , Macrodicella and Architesma the tegumen is straighter and its arms are anteriorly narrower and fused only in their anterior third or less). The ventral ends of the arms of the tegumen are rounded and swollen whereas they are flattened and tapered in other similar genera. (4) The arms of the vinculum are narrow but heavily sclerotised (vs. broader, strip-like arms in other similar genera). (5) The valva is short, approximately as long as the tegumen-vinculum complex (similar to Acanthosia , which has, however, a longer distal saccular process, whereas the valva is considerably longer than the tegumen-vinculum complex in Asbolopsyche , Macrodicella and Architesma ). (6) The costa is short and occupies only the basal section of the dorsal margin of the valva. (7) The editum is elongate and narrow, ca. half of the valva length, directed to the center of the valva at an acute angle to its dorsal margin, basally fused with the costa, and bears a conical ampulla apically. (8) The tendon is present but very short. The main part of the diaphragmal section of the transtilla is membranous. (9) The basal saccular process is robust and relatively long, reaching the dorsal corner of the basis valvae or exceeding it. (10) The dorsal margin of the saccular pocket possesses an irregularly dentate, crest-like process medially whereas the sacculus of Acanthosia , Macrodicella and Architesma is smooth and only in Asbolopsyche is it scobinate or spinulose. (11) The distal saccular process is short and leaf-shaped, with irregularly dentate margins, flattened and with a setose crest on its inner surface. (12) The ental ends of the sacculi are elongate but fully separated from each other by the intersaccular membrane (similar to Asbolopsyche whereas in other genera of the complex the sacculi are articulated by the gelatinous intersaccular bridge). (13) The juxta is solid and separated from the ental ends of the sacculi by a thin membrane (whereas in other similar genera the juxta is articulated with the ental ends of the sacculi, except for Asbolopsyche , in which, however, the juxta consists of two plates articulated by a thick membranous fold). (14) The anellus is membranous with thin and weakly sclerotised, ribbon-like transverse plates dorsally and ventrally. (15) The phallus is large and broad in proportion to the genital capsule, the largest in the generic complex, with a broad and rounded coecum. (16) The vesica possesses one or two subbasal diverticula, the largest, tubular distal diverticulum with a short subdiverticulum in its distal half, which bears a claw-shaped cornutus. Female ( Fig. 150 View Figures 150–155 ). (1) The 8 th tergite is moderately sclerotised and band-like whereas the 8 th sternite is medially membranous and finely scobinate but with trapezoidal lateral sclerotised plates (a feature unique within the generic complex), the postero-lateral, tapered ends of which are articulated with the bases of the apophyses anteriores while their anterior and dilated ends are connected to the latero-posterior margins of the sterigma by the thin gelatinous folds. (2) The postvaginal formation of the sterigma consists of a smooth anterior trapezoidal plate with a postero-medial concavity anteriorly encircling the rounded and weakly gelatinous postero-medial fold. (3) The antevaginal section of the sterigma is represented by the weakly sclerotised, narrow, transverse strip-like antevaginal plate. (4) The ductus bursae is short and dorso-ventrally flattened, heavily sclerotised ventrally and membranous dorsally. (5) The posterior section of the corpus bursae is somewhat narrower than the anterior one, heavily sclerotised anteriorly and medially, and weakly gelatinous and rugose posteriorly, with a short but broad ventro-lateral pocket medially. (6) The anterior section of the corpus bursae is posteriorly gelatinous, rugose and with short lateral diverticula, while its anterior section is membranous, finely scobinate and bears a small signum dorsally (whereas in other genera of the generic complex it is entirely membranous and finely scobinate). (7) The appendix bursae is short, conical or semiglobular, membranous, covering the ductus bursae ventrally.

Distribution. The genus has the largest range in the generic complex, which stretches from south-eastern Guinea in the west to southern Ethiopia in the east and reaching southern Mozambique in the south.