One of North America’s endemic hornworts, Phaeoceros proskaueri Stotler, Crand.-Stotl. & W.T.Doyle [also known as Paraphymatoceros proskaueri (Stotler, Crand.-Stotl. & W.T.Doyle) J.C.Villarreal & Cargill] was described from plants collected in the Monterey Bay area of California. Another key North American hornwort, Phymatoceros phymatodes (Howe) Duff, Villarreal, Cargill & Renzaglia [sometimes synonymised with the European Phymatoceros bulbiculosus (Brot.) Stotler, W.T.Doyle & Crand.-Stotl.], is known from the same location.

For Spring Break in 2011, we flew from Connecticut to Phoenix, picked up a hire car, and set off on an epic road-trip though Arizona and California. Alongside sightseeing highlights that included Meteor Crater, Sunset Crater VolcanoGrand Canyon National Park, the Painted Desert and Petrified Forest,  Yosemite National Park, Joshua Tree National Park, Saguaro National Park and Mojave National Preserve, stunning areas for natural history (but legally out-of-bounds for plant collecting), we spend a few days over on the west coast, in Santa Cruz.

We were visiting Professor William Doyle and his wife. Bill was one of the University of Santa Cruz’s founding  faculty, having been there since its inception in 1965.  One of very few former students of eminent bryologist Professor Johannes Proskauer, who died in Berkeley, California aged only 47, Bill has authored some groundbreaking publications. These include his work on inheritance, using the complex thalloid liverwort Sphaerocarpos as a model, published in the journal Nature in 1960. He also collected the sample of Phaeoceros proskaueri on which the species name was based, and so was able to take us to the type locality:

Bill Doyle, Juan Carlos Villarreal and Lilia Villarreal-Forrest at the type locality for Paraphymatoceros (Phaeoceros) proskaueri

DNA sequence data from our collection of Phaeoceros phymatodes from that trip are included in Villarreal et al.’s 2013 paper on the plastid genome of the hornwort Nothoceros aenigmaticus (R.M.Schust.) J.C.Villarreal & K.D.McFarland.

In addition to the hornworts, we collected a couple of species of the complex thalloid liverwort Asterella nearby; both Asterella bolanderi (Aust.) Underw. and Asterella californica (Hampe) Underw. were growing in mats on open areas by the roadside.

Lilia Villarreal-Forrest on a carpet of Asterella bolanderi




Barbara J. Crandall-Stotler, Raymond Stotler, William T. Doyle & Laura L. Forrest, 2008. Phaeoceros proskaueri sp. nov., a new species of the Phaeoceros hallii (Austin) Prosk.—Phaeoceros pearsonii (M. Howe) Prosk. complex and the systematic affinities of Paraphymatoceros Hässel. Fieldiana Botany 47: 213-238.


Juan Carlos Villarreal A., Laura L. Forrest, Norman Wickett & Bernard Goffinet, 2013. The plastid genome of the hornwort Nothoceros aenigmaticus (Dendrocerotaceae): Phylogenetic signal in inverted repeat expansion, pseudogenization, and intron gain. American Journal of Botany 100: 467-477.