A Plant Mystery Solved

A plant mystery solved!
Undescribed species in the Garden gets a name

The Garden’s collections usually grow by exchanging plants with other institutions and experts, or by collecting trips. On receiving new plants at the Garden they may not even be fully identified and may grow in the collections for many years before they are described by an expert on a particular genus or family.

For instance, the striking liana pictured above came to the Garden in 1992 from Strybing Arboretum (now Gardens of Golden Gate Park), identified only to the genus Paullinia. It had been collected by Dennis Breedlove and a colleague in November 1991 in a cloud forest in Chiapas, Mexico. Breedlove suspected this liana to be an undescribed species at the time he collected it.

Dr. Breedlove worked briefly at the Garden as a research botanist in the late 1960s, eventually leaving to work at the California Academy of Sciences (CAS). His research focused on a flora of Chiapas that was incomplete at the time of his death in 2012.

Image above: Type specimen of Paullinia hondurensis in the US National Herbarium. An appropriate herbarium specimen is chosen by the authors of the new species as a permanent reference and to fix the new name when referenced in a publication. Photo courtesy of the US National Herbarium

Persistence Pays Off

Holly Forbes, the Garden’s previous curator, sought to learn the identity of the Garden’s accession for a number of years and her persistence paid off in April of 2024.

She contacted Dr. Emily Magnaghi at CAS to find out if Breedlove’s herbarium sheet (a dried, pressed plant specimen) had been identified in the intervening years (a previous attempt years earlier to find the sheet at CAS was unsuccessful). Dr. Ricardo Kriebel of CAS located Breedlove’s sheet and sent a specimen image to Dr. Pedro Acevedo-Rodriguez at the National Museum of Natural History of the Smithsonian Institution for help with identification. Dr. Acevedo-Rodriguez was excited to see that it was an example of a new species Paullinia hondurensis, described in his recently (2018) published paper.* In his paper, he writes that it is “Known only from four localities from montane cloud forests (1990–2000-meter elevation) in Guatemala and Honduras.”

These authors were not aware of the unnamed herbarium specimen at the California Academy of Sciences nor of the plants growing here at the Garden and the Gardens of Golden Gate Park! They can now add a range extension of Paullinia hondurensis to Chiapas, Mexico.

Garden staff made herbarium sheets at the Garden in 2015 and 2016, placing these sheets in the UC Berkeley Herbarium. In 2024 new herbarium sheets of the Garden’s plant in fruit and in flower were made for Acevedo-Rodriguez for his records at the National Museum of Natural History, as well as for CAS.

This story illustrates the importance of maintaining and documenting living plant collections around the globe. The collaboration and communication between researchers, curators and horticulturists was key to creating a more complete picture of plant diversity in the Garden’s collection.

You can visit the largest of the Garden’s (three) specimens of Paullinia hondurensis in Bed 175 along the walkway to the entrance of Julia Morgan Hall, expertly tended by Horticulturist Eric Schulz.

Even though we strive to have the correct name on all of our labels in the Garden, sometimes new information or examination will reveal a different identification, and therefore, other species new to science might well be lurking in the collections!

* coauthored by Genise Vieira Somner of the Universidade Federal Rural do Rio de Janeiro, in PhytoKeys 2018, Vol. 114: pls 95–11.