A synopsis ofChaenothecain North America, including a new species from southern Ontario,C. selvae, supported by morphometric analyses

Abstract

We describe and illustrate a new species of calicioid lichen from southern Ontario, Chaenotheca selvae. We place it in Chaenotheca because of its lichenized thallus with a Stichococcus photobiont, a brown mazaedium, and ascospores that are brown, spherical, and single-celled (3.0–3.6 μm in diam.). It differs from other species of Chaenotheca by its photobiont, non-ornamented ascospores, straight stalks, and producing orange-brown pruina on the mazaedium, excipulum, and upper portion of the stalk when mature. Using a detrended correspondence analysis we identified 25 taxa, including the sp. nov., analyzing 22 morphological characters. Our results provide evidence of chemical and morphometric variation among species of Chaenotheca. We also provide a key for the identification of the 25 Chaenotheca species in North America.