SANTA CRUZ — Emeritus Director of Research at the UC Santa Cruz Arboretum & Botanic Garden Stephen McCabe has recently described and named two new species of succulent plants, which he found growing on a remote island off the coast of Baja California.
“I’ve always loved succulents and there seems to be a lot going on with the evolution within this group that’s very interesting,” said McCabe. “Hopefully they can teach us more about how new species evolve.”
The two newly named species both belong to the genus, Dudleya, which McCabe has been studying for more than 40 years. Other species in the genus, described as “charismatic,” according to McCabe, have been historically sought after by poachers as the plants are very popular in Asia, and sold at a high markup on the black market.
“They became like pet rocks,” said McCabe. “The middle and upper classes, particularly in China, wanted a Dudleya pachyphytum or Dudleya farinosa for their windowsill and they are willing to pay outrageous prices for them.”
Naming each species in the genus helps to bolster conservation efforts. Because Dudleya plants are prone to hybridize between species and grow in specialized habitats, similar to oaks and manzanitas, according to McCabe, it makes it difficult to name new species because one can appear very similar to another.
In fact, McCabe first studied and grew a cutting of one of the species he recently dubbed Dudleya delgadilloi back in 1986, but the offspring he grew from the cutting didn’t match up with the parent plant, and he realized that he’d need to study it in the wild. In order for him to do so, he had to embark on an arduous journey to the remote Cedros Island, off the coast of Mexico.
“I had to drive 1,000 miles just to get to the airport to fly out to the island,” said McCabe. “It’s so remote that people haven’t been able to visit very often, but it really helps to see the plants in the wild to understand whether or not you have something new.”
On the island, McCabe discovered that he did in fact have two new species on his hands. One, which has narrow leaves with pointed tips to catch fog, he named Dudleya delgadilloi in honor of a prominent Mexican botanist, José Delgadillo Hernandéz, professor and director of the herbarium at the Universidad Autónoma Baja California en Ensenada.
McCabe mentioned that not only is Delgadillo an accomplished botanist and teacher, he also helped McCabe in a big way when he was in a bind.
“He’s a really inspiring professor training the next generation of botanists and conservationists in Baja California,” said McCabe. He also gave me his seat on a boat out to visit a tiny island off the coast of Guadalupe Island, which I really wanted to get to.”
McCabe named the second species Dudleya cochimiana in honor of the local Indigenous people known as the Cochimí. This species may look similar to other plants in the Dudleya genus, but he confirmed during his visit that it is a distinct plant, which grows in concentrated populations of the island, from the splash zone of the waves to the ridgetops.
“Many times botanists will come in from another country and honor other people,” said McCabe. “In this case, I wanted to make sure that I honored a botanist from Baja California and the indigenous peoples.”
Now that the two plants have been formally named using the rules in the International Code of Botanical Nomenclature, it is easier for the two distinct species to get local, federal or international conservation protections.
“It’s important,” said McCabe, “If something really is a distinct species that it gets named.”
The two new species will now have seeds on file and be growing at the UCSC Arboretum & Botanic Garden and other botanic gardens in the United States and Mexico such as the garden associated with the university in Ensenada, Baja California.
Now that he has completed the process of naming the two succulent plants, McCabe is already working on naming other species of Dudleya plants, four in total, which he hopes will be formalized in the next year or two.
“I hope that it helps with the conservation of these species,” said McCabe. “And generates more appreciation, both in the United States and Mexico for many of the rare plants that exist in Baja, California.”
McCabe will be discussing Dudleyas and the naming process virtually at 7 p.m. March 13. For information about the talk, visit cruzcnps.org.
To read McCabe’s paper about the two species, visit bioone.org.
