Completing the Aphid Survey of GSMNP
Completing the Aphid Survey of GSMNP
Aphids are small plant-feeding insects with complicated life cycles. Species of aphids are generally restricted to a narrow taxonomic range of hosts, and host identity is usually necessary for correctly identifying an aphid. The 2005 season marks the third and final year of an aphid survey of the Great Smoky Mountains National Park, already shown to harbor a diverse aphid fauna. In 2005, areas of the park that contain particular plants known to host aphids will be targeted for sampling, with particular emphasis given to those ecological areas not yet sampled. Among other plants, sedges, ferns, and asters will be targeted, and mud flats, balds, and other unique areas will be visited. Furthermore, many aphids are tended by ants, and working out aphid-ant relationships will be a secondary focus of the project.
The third of three DLIA-funded projects to catalog the aphids of the Great Smoky Mountains National Park took place from 2005 to 2007, with collecting trips made in September 2005 and June 2006, and laboratory work conducted in 2007. In all, 269 aphids were mounted to microscope slides, representing material of 45 named aphid species from 36 park localities and on 39 different host plant species. Some aphid material was not identifiable to the species level, but did represent an additional 11 species. DNA was extracted from 68 specimens for future taxonomic work. This project found 22 species never before recorded from the park. Several noteworthy findings used DNA sequence data from GRSM aphids to assist with specimen identification. For example, an aphid collection was made on false foxglove (Aureolaria laevigata, family Scrophulariaceae) in June 2006, but there are no host-based keys for this plant. However, the genetic match between this aphid and A. illinoisensis (previously collected on grape, Vitis aestivalis, family Vitaceae) was perfect. Upon anatomical comparison, it was clear that the two samples were of the same species. This collection represents a dramatic expansion of the known host range for this aphid species.
