The genus Roddia was named in honour of the Russian entomologist Evgenii Georgevich Rodd (Korshunov and Gorbunov 1995). The common name "tortoiseshells" is shared with the genera Nymphalis and Aglais because the species in all three genera were originally placed in the genus Aglais.
There is only a single species in this genus, the Compton Tortoiseshell, Roddia I-album, although it may eventually be demonstrated that the North American subspecies j-album is actually a separate species from the Asian I-album. Roddia I-album has traditionally been called Nymphalis vau-album (Denis & Schiffermüller, [1775]). Compton Tortoiseshells are large, golden brown butterflies that are frequently very abundant in the BC interior, especially in the fall.
The genus Roddia Korshunov was described in 1995, with Papilio I-album Esper, 1780 as the type species (Korshunov and Gorbunov 1995). Roddia is more closely related to Polygonia than to Nymphalis, according to comparisons of mitochondrial and nuclear DNA (Soren Nylin, pers. comm.). This is supported by several characteristics it has in common with Polygonia: the white "comma" marking on the ventral hindwing, the sexual dimorphism in ventral wing colour, the pair of branched spines on the top of the head of the larva, and the branched mid-dorsal spines on all abdominal segments of the larva. As a result Roddia could be treated either as a subgenus of Polygonia or as a full genus. We have chosen to treat Roddia as a full genus because of differences from Polygonia, such as wing shape and genitalia that more closely resemble those of Nymphalis.
The species name I-album was generally used until dos Passos (1964) and Higgins and Riley (1970) treated the species as vau-album (Denis & Schiffermüller, [1775]). The North American j-album was treated as a separate species until dos Passos (1964) placed it as a subspecies of vau-album. Koçak (1981) concluded that the species name vau-album is a nomen nudum, or "naked name," a name not attached to a specific taxon, by Article 12.1 of the International Code of Zoological Nomenclature. The first available valid name for the species is the traditionally used I-album Esper, 1780, which Koçak recommended be returned to use. Kudrna (1986) agreed with this approach, although Sattler and Tremewan (1984) and
Sattler (1989) disagreed on the grounds that vau-album was the accepted (modern) usage. Karsholt and Razowski (1996) followed Sattler's recommendation that all Denis and Schiffermüller names be retained "as the opposite view will have incalculable consequences for the stability of the nomenclature of European Lepidoptera." We disagree with this uncritical approach, preferring that of Kudrna (1986), in which each name is looked at individually, retaining only those Denis and Schiffermüller names that actually need to be retained for nomenclaturaI stability. The name vau-album is not one of those names.
The name I-album was in use for the 184 years between its description by Esper in 1780 and its rejection by dos Passos (1964), whereas the use of vau-album has still been disputed (e.g., Koçak 1981; Kudrna 1986) in the few decades since dos Passos (1964) and Higgins and Riley (1970). As a result of these changes in genus and species, Nymphalis vau-album is correctly called Roddia I-album.
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