Correlations between Lichen Secondary Chemistry and Grazing Activity by Pallifera varia

Publisher Website
Google Scholar
Abstract
Individuals of the slug P. varia were observed under field conditions in a talus slope habitat in Shenandoah National Park [Virginia, USA] during late summer, 1979. Slugs were most frequently observed feeding on the crustose lichen Aspicilia gibbosa. A quantitative analysis of saxicolous cryptogam coverage and frequency in the study area demonstrated that Aspicilia spp. and several other lichen species exhibited relatively high importance values in the community. TLC of fecal material obtained from field collected slugs was done to ascertain the feeding preferences of slugs under field conditions. Aspicilin, a lichen secondary compound produced by Aspicilia spp., was extracted from slug fecal material most frequently. Laboratory experiments designed to determine lichen species preferred by slugs established a preference gradient with Aspicilia spp. most preferred and Xanthoparmelia cumberlandia and Huilia albocaerulescens actively avoided. Slugs do not feed on lichen species most frequently encountered in the community. They appear to make food choices based at least partly on lichen chemistry. Stictic acid and protocetraric acid appear to function as anti-herbivore compounds in observed slug-lichen interactions.

This publication has 1 reference indexed in Scilit: