The Systematics, Evolution, and Ecology of Hawaiian Cydia (Lepidoptera: Tortricidae)
- Author(s): Oboyski, Peter T.;
- Advisor(s): Roderick, George K;
- et al.
Cydia Hübner 1825 is a genus of moths in the family Tortricidae with 231 named species and subspecies and is distributed on all continents except Antarctica. As larvae, many species feed within reproductive structures, such as fruits, seeds, and flowers, under bark, or within fleshy stems of at least 65 host-plant species including angiosperms and conifers. Many species, including codling moth, pea moth, spruce seed moth, pine seedworms, filbertworm, and hickory shuckworm are considered pests of agriculture and forestry. As a result, the biology, natural enemies, and pheromones of several species have been well-studied.
The nomenclature and classification of Cydia has also been well-studied but is less resolved. Nineteen different genus names have been proposed for species in this genus, with Laspeyresia Hübner, and Carpocapsa Treitschke being in common usage until relatively recently. Following the rules governing the International Code of Zoological Nomenclature, Cydia is the valid genus name for all species congeneric with the codling moth, Cydia pomonella (Linnaeus), the type species of the genus. The relationship of Cydia to other genera in the tribe Grapholitini is a topic of continued debate. Some authors have suggested that the tribe is an evolutionary grade while others have presented evidence that Grapholitini is a monophyletic clade. Although some secondary sexual characters have been proposed, the genus Cydia can claim no synapomorphies that can be found in all Cydia species. To better understand the systematics and evolution of this group more detailed morphological, molecular, and ecological data are needed for non-pest species.
At least 21 endemic species of Cydia are known from the Hawaiian Islands. Males of most species have a ventral pouch below the cubital vein of the hindwings similar to C. latiferreana (Walsingham), C. maackiana (Danilevsky), and several other Cydia species to a lesser extent, although this feature appears to have arisen independently in the Hawaiian group. Larvae, where known, feed on endemic plants in the family Fabaceae. Identification of species is made difficult by extreme polymorphism of wing patterns for some widespread species and a general reduction of morphological features in the genitalia of male moths, while some features of female genitalia, particularly the antrum and lamella postvaginalis, have diagnostic value. Eight new species of Hawaiian Cydia are described (C. mauiensis n.sp., C. velocilimitata n.sp., C. haleakalaensis n.sp., C. makai n.sp., C. koaiae n.sp., C. hawaiiensis n.sp., C. acaciavora n.sp., and C. anomalosa n.sp.) based on wing patterns and features of male and female genitalia. The thirteen previously known species are redescribed because original descriptions were inconsistent among authors and based solely on wing patterns. Distributions, host-plant affinities, and natural enemies for each species are discussed.
A molecular phylogeny of 66 specimens representing 14 Hawaiian Cydia species plus 20 outgroup species was constructed using nuclear and mitochondrial DNA to assess the relative importance of host-plant affinities and geographic isolation in their diversification. Hawaiian Cydia is monophyletic and nested well-within the genus. They appear to have arrived in the Hawaiian Islands after the rise of Maui based on the basal position of several Maui and Hawaii Island species throughout the phylogeny. The earliest diverging species feed on Canavalia and dispersed across the high islands. Subsequent shifts to feeding on Sophora chrysophylla then Acacia koa were followed by speciation and the filling of these niches across the islands. The origin of Hawaiian Cydia remains obscure, but appears to be a separate colonization of remote Oceania from Cydia pseusomalesana Clarke in French Polynesia.
It is likely that several more species of Hawaiian Cydia await discovery while several others probably have gone extinct in the 100 years since they were first collected. A broader survey of outgroup taxa from Asia and the Americas, and more informative genes in a molecular phylogeny may help resolve the origins of Hawaiian Cydia.