Forewing above in cellules 1 b—8 with distinct, small, usually double submarginal dots, but beneath without large submarginal spots; the median band formed almost as in nireus, though the spot in cellule 2 covers the base of the cellule, but is more produced anally than the spot in 1 c, which does not reach the cell. — Sierra Leone to the Congo region and Uganda.[4] The median band is straight and regular and never less than 1 cm in cell lb of the forewing, nearly always much wider.
P. s. sosia (Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana, Togo, Benin, southern Nigeria, western Cameroon)
P. s. pulchra Berger, 1950 [5](Cameroon, Gabon, Congo, Central African Republic, northern Angola, Congo Republic)
P. s. debilis Storace, 1951 [6] (Uganda, northwestern Tanzania)
Taxonomy
Papilio sosia belongs to a clade called the nireusspecies group with 15 members. The pattern is black with green or blue bands and spots and the butterflies, although called swallowtails, they lack tails with the exception of Papilio charopus and Papilio hornimani. The clade members are:
^Aurivillius, [P.O.]C. 1908-1924. In: Seitz, A. Die Großschmetterlinge der Erde Band 13: Abt. 2, Die exotischen Großschmetterlinge, Die afrikanischen Tagfalter, 1925, 613 Seiten, 80 Tafeln (The Macrolepidoptera of the World 13).Alfred Kernen Verlag, Stuttgart. This article incorporates text from this source, which is in the public domain.
^Berger, Lucien A., 1950 Catalogues raisonnes de la faune entomologique du Congo Beige.Lepidopteres-Rhopaloceres. I.-Fam. Papilionida:" [in French). Ann. Mus. Congo Belge C. Zool. Serie III (II), voJ.8: pp.1-L04, 96 figs. 1950.
^Storace, L. (1951-1952). Recherches sur le groupe africain de Papilio nireus L. Lambillionea 51:44-52; 54-57; 73-76.
Sources
Carcasson, R.H. (1960). "The Swallowtail Butterflies of East Africa (Lepidoptera, Papilionidae)". Journal of the East Africa Natural History Societypdf Key to East Africa members of the species group, diagnostic and other notes and figures. (Permission to host granted by The East Africa Natural History Society)