Rare Lichen Discovered at More Bay Area National Park Sites

The rare island tube lichen, Hypogymnia schizidiata, photographed in the Marin Headlands, where it was not known to occur until recently.

© catchang / Photo 11276474 / October 2017 / iNaturalist.org / CC BY-NC

November 2017 - In 2015, biologists found the globally rare island tube lichen (Hypogymnia schizidiata) on Montara Mountain during a baseline lichen inventory for the Rancho Corral de Tierra unit of the Golden Gate National Recreation Area. Last year, a follow-up survey revealed even more H. schizidiata in the same area and confirmed a 280-mile northern range extension for the species. The lichen was originally described from specimens collected from the Channel Islands in Ventura County, California in the 1980s.

Observations in several more locations in 2016-17 have confirmed that the lichen’s range extends even farther north by more than 100 miles. Two of the new sites found to harbor populations of H. schizidiata are within the Golden Gate National Recreation Area and Point Reyes National Seashore in Marin County. In one location, the lichen was found growing on chert, a rock substrate that was not previously known to support this species. In the other, many specimens were seen growing on conifer bark.

With each of these new finds, biologists have learned more about the habitat requirements of H. schizidiata. For example, all of the populations have been found within four miles of the ocean. Also, while the lichen does not appear to be picky about precisely what it grows on, the majority of the populations have been found on or near stands of old-growth shrubs. This is valuable data that will allow biologists to conduct more targeted searches for the lichen the future. It is also enables land managers to make more informed decisions about how to conserve this rare species.

Contact Susie Bennett, National Park Service Natural Resources Specialist, or Tom Carlberg, Field Associate with the California Academy of Sciences, to learn more.