Aphonopelma johnnycashi, named for Johnny Cash, can be found around Folsom State Prison in California, where Cash made a famous recording and about which he wrote a hit song called "Folsom Prison Blues." The males of aphonopelma johnnycashi are generally black, mirroring Cash's famous penchant for dressing in black, said biologist Chris A. Hamilton, who did this research while at Auburn University.
Hamilton conducted the research with Brent E. Hendrixson of Millsaps College and Jason E. Bond, also of Auburn. Their findings were published Thursday in the journal ZooKeys
said the research "rewrites scientific understanding" of Aphonopelma, an understudied genus of harmless North American tarantula. In addition to identifying Johnny Cash and 13 new species, the team reclassified 40 old names, suspending some and combining others, leaving 29 species in the United States -- down from 55 when the team started.
"The real surprise is just how much novel diversity we found in the United States, a place that most of the public would probably think has been surveyed really well," said Hamilton, who was with Auburn University Museum of Natural History in Alabama during the research.
Tarantulas are notorious for having morphological characteristics that stymie efforts to define species, Hamilton said. The team collected specimens though fieldwork and a "citizen science" program
to which the public could contribute. Researchers used genomics, a branch of molecular biology concerned with the structure, function, evolution and mapping of genomes, to examine species boundaries within the group.
Aphonopelma johnnycashi was thought to be part of another species found in the foothills along the western Sierra Nevadas, Hamilton said. A closer look across the distribution at their structure, DNA and ecological variables indicated some specimens were unique and warranted being a separate species due to their evolutionary trajectory, Hamilton said.
"Species underlie pretty much everything we do in biology, so it's very important for researchers to have a solid understanding of the species we are using in our research," Hamilton said.
While naming a new species after a famous person makes for good headlines, most species are named for unique characteristics or provenance. Another newly discovered species, the Aphonopelma xwalxwal, can be found in the area where Cahuilla Native Americans are from, and the word "xwalxwal" means "spider" in their language, said Hamilton, a member of the Chickasaw Nation in Oklahoma. Another, Aphonopelma madera, was named for mountain ranges in the "sky islands" region of Arizona.
None of the species are in immediate danger of going extinct, Hamilton said. But many live in habitats where climate, human expansion and habitat degradation are likely to be a major influence on their future.