Eucosma

Abstract: The sex pheromones of three Cryptophlebia, one Centroxena, and one Eucosma species (Lepidoptera: Olethreutinae) inhabiting mangroves in the Ryukyu Islands, Japan, were studied with coupled gas chromatography-electroantennographic detection, and GC-mass spectrometry (GC-MS). The larvae of each Cryptophlebia species are specifically associated with viviparous seedlings from one of three mangrove Rhizophoraceae plants. Whereas three EAG-active alcohol components, (Z)-8-dodecen-1-ol, (E)-8-dodecen-1-ol, and dodecan-1-ol, in a ratio of 100:12:4, were identified from the pheromone gland extract of female of C. horii (host: Bruguiera gymnorrhiza), two other sibling species produced the corresponding acetates, i.e., (Z)-8-dodecenyl acetate, (E)-8-dodecenyl acetate, and dodecyl acetate, in a 100:2:3 ratio from Cryptophlebia palustris (host: Rhizophora stylosa in Iriomote-jima Island) and in a 100:7:13 ratio from C. amamiana (host: Kandelia candel in Amami-oshima Island). The double bond positions of the monounsaturated components were confirmed by GC-MS analyses of their adducts with dimethyl disulfide. On the other hand, the larvae of Centroxena sp. feed on fruits of Sonneratia alba, another mangrove plant in the Sonneratiaceae, and the extract of the female pheromone glands contained (8E,10E)-dodecadienyl acetate and dodecyl acetate in a ratio of 100:5. The double bond position of the diunsaturated compound was confirmed by GC-MS analysis of its adduct with 4-methyl-1,2,4-triazoline-3,5-dione. (E)-9-Dodecenyl acetate was exclusively identified in the pheromone gland extract of Eucosma coniogramma females reared from seedlings of B. gymnorrhiza. Although the roles of minor components have not been revealed by field tests, synthetic lures baited with the main pheromone component of each species successfully attracted the target males, confirming that the sex pheromone is one of the most important factors for their reproductive isolation.

Abstract: Eucosma Hubner is the largest genus in Tortricidae, currently comprising 298 described species. Its circumscription and those of the closely related genera Pelochrista Lederer, Phaneta Stephens and Epiblema Hubner have long been matters of confusion. Prior to the mid-1920s, assignment to any of these genera was largely arbitrary due to a lack of clearly defined morphological limits. Here we present the first study to examine the monophyly of Eucosma and related genera using a molecular phylogenetic framework. We find that the Eucosma/Pelochrista group splits into three lineages: (i) a new genus of Pinaceae-feeding species formerly assigned to Eucosma; (ii) a refined notion of Eucosma that is consistent with Palearctic usage and includes current North American Phaneta; and (iii) a refined concept of Pelochrista that is distinguishable from Eucosma based on female genital morphology. The new genus, described here as Eucopina Gilligan & Wright gen.n., contains the following species: Eucopina bobana (Kearfott) comb.n.; E. cocana (Kearfott) comb.n.; E. crymalana (Powell) comb.n.; E. franclemonti (Powell) comb.n.; E. gloriola (Heinrich) comb.n.; E. monitorana (Heinrich) comb.n.; E. monoensis (Powell) comb.n.; E. ponderosa (Powell) comb.n.; E. rescissoriana (Heinrich) comb.n.; E. siskiyouana (Kearfott) comb.n.; E. sonomana (Kearfott) comb.n.; E. tocullionana (Heinrich) comb.n. In addition, Ioplocama Clemens syn.n. is synonymized with Eucosma and Pygolopha Lederer syn.n. is synonymized with Pelochrista. This work is the basis for a revised world catalogue of Eucosma, Pelochrista and Phaneta in preparation.

Abstract: Eurytoma pini Bugbee (Bugbee, 1958), a common parasite of the European pine shoot moth, Rhyacionia buoliana (Schiff.), in Ontario, was previously recorded from this host as E. appendigaster (Swed.) (Coppel and Arthur, 1953) and as E. thylodermatis Ashm. (Miller, 1953). Bugbee (1958) recorded it from various lepidopterous hosts that mine in plant tissues. These include: the Nantucket pine tip moth, Rhyacionia frustrana (Comst.); the bagworm, Thyridopteryx ephemeraefomis (Haw.); the ragweed borer, Epiblema strenuana (Walkr.); the lima bean borer, Etiella sp.; the pink bollworm, Pectinophora gossypiella (Saund.); Acrobasis rubrifasciella Packard; and Eucosma scudderiana (Clemens). Bugbee stated that the range of E. pini probably includes all of the pine growing regions of North America.

Abstract: Wildings from exotic tree plantations are a major threat to New Zealand’s native vegetation and landscapes. The insects associated with the reproductive structures of the most significant invasive tree, Pinus contorta, are reviewed with regard to their suitability for biological control. Based on host species and structure specificity and their impact on seed production, Conophthorus ponderosae (Scolytidae), Eucosma rescissoriana (Tortricidae) and Pissodes validirostris (Curculionidae) are the most promising biocontrol candidates among the 16 North American or Eurasian insect species recorded as feeding on P. contorta cones. Further studies are needed to assess whether these insects could significantly reduce the rate of spread of P. contorta and would not pose a threat to any native plants or plantation forestry trees.