Genomic data reveal local endemism in Southern California Rubber Boas (Serpentes: Boidae, Charina) and the critical need for enhanced conservation actions

Jesse Grismer; Peter Scott; Erin Toffelmier; Brian Hinds; Randy Klabacka; Glenn Stewart; Virginia White; Jamie Oaks; H Bradley Shaffer

doi:10.1016/j.ympev.2022.107542

Genomic data reveal local endemism in Southern California Rubber Boas (Serpentes: Boidae, Charina) and the critical need for enhanced conservation actions

Mol Phylogenet Evol. 2022 Sep:174:107542. doi: 10.1016/j.ympev.2022.107542. Epub 2022 Jun 8.

Authors

Jesse Grismer¹, Peter Scott², Erin Toffelmier³, Brian Hinds⁴, Randy Klabacka⁵, Glenn Stewart⁶, Virginia White⁵, Jamie Oaks⁵, H Bradley Shaffer³

Affiliations

¹ Department of Ecology and Evolutionary Biology, La Kretz Center for Californian Conservation Science, and Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095, USA; Department of Biological Sciences and Museum of Natural History, Auburn University, Auburn, AL 36849, USA; Department of Biology, La Sierra University, Riverside, CA 92515, USA. Electronic address: jgrismer@lasierra.edu.
² Department of Ecology and Evolutionary Biology, La Kretz Center for Californian Conservation Science, and Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095, USA; Department of Life, Earth, and Environmental Sciences, West Texas A&M University, Canyon, TX 79016, USA.
³ Department of Ecology and Evolutionary Biology, La Kretz Center for Californian Conservation Science, and Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095, USA.
⁴ Department of Biology, La Sierra University, Riverside, CA 92515, USA.
⁵ Department of Biological Sciences and Museum of Natural History, Auburn University, Auburn, AL 36849, USA.
⁶ Department of Biological Sciences, California State Polytechnic University, Pomona, CA 91768, USA.

PMID: 35690376
DOI: 10.1016/j.ympev.2022.107542

Abstract

The mountains of southern California represent unique, isolated ecosystems that support distinct high-elevation habitats found nowhere else in the area. Analyses of several moisture-dependent species across these sky-islands indicate they exist as locally endemic lineages that occur across these fragmented mountains ranges. The Rubber Boa is a semi-fossorial snake species that is widely distributed in the cooler and more moist ecoregions regions of western North America, including isolated populations across southern California mountain ranges. We developed a genomic and ecological dataset to examine genetic diversity within Rubber Boas and to determine if the endemic Southern Rubber Boa represents a distinct lineage. We quantified current and future habitat suitability under a range of climate change scenarios, and discuss the possible environmental threats facing these unique montane isolates. Our results support four major lineages within Rubber Boas, with genetic breaks that are consistent with biogeographic boundaries observed in other co-distributed, cool-temperature, moisture adapted species. Our data support previous studies that the Southern Rubber Boa is an independent evolutionary unit and now includes multiple locally endemic sky-island populations, restricted to isolated mountain tops and ranges across southern California. Analyses of future habitat suitability indicate that many of these sky-island populations will lose most of their suitable habitat over the next 70 years given predicted increases in drought, rising temperatures, and wildfires. Collectively these data emphasize the critical conservation needs of these montane ecosystems in southern California under current and projected climate change conditions.

Keywords: California floristic province; Charina; Conservation; Montane; RADseq; Rubber Boas; Sky-islands; Southern California.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Animals
Boidae*
California
Ecosystem
Genomics
Phylogeny
Rubber

Substances

Rubber