Abstract Detail

Ericaceae: Systematics, Ecology and Evolution

Morrison, Glen R [1], Huang, Yi [2], Saavedra, Natalie [3], Sanders, Andrew [3], Stoughton, Thomas [4], Wahlert, Gregory [5], Vasey, Michael [6], Keeley, John [7], Parker, V. T. [8], LITT, AMY [9].

How many manzanitas? Preliminary genetic analyses do not distinguish some currently recognized species.

The manzanitas (Arctostaphylos Adanson, Ericaceae) are the most species-rich woody plant genus in the California flora. Manzanitas are evergreen shrubs and small trees that occur in many ecosystems, and are known for their distinctive colorful bark, twisting branches and urn-shaped flowers. While manzanitas are distinct as a group, manzanita species are often similar morphologically, making species identification difficult. In addition, some species show substantial intraspecific variation, and hybridization is thought to occur often. Further, many manzanita species occur on unique soils over restricted ranges, raising the question of whether they represent distinct evolutionary lineages or plastic phenotypes associated with the unique ecological conditions. These issues raise questions regarding the genetic and evolutionary distinction of some species. Previous genetic analyses, which sought to assess evolutionary divergence among manzanita species, found low levels of ITS sequence variation among species, and thus provided little clarification of species boundaries in this challenging group. Furthermore, in previous analyses many taxa have been represented by only one sample, limiting the ability of these studies to distinguish between intraspecific and interspecific variation. In this study, we used double digest restriction site-associated DNA sequencing to generate thousands of single nucleotide polymorphisms for over 200 individuals representing 27 species collected in Southern California and the Central California Coast region. We used distance-based and tree-based methods to assess whether the structure of genetic variation in the sampled species corresponds to currently circumscribed species. Preliminary results from this study demonstrate that some species are genetically coherent, while others appear genetically intermixed with one or more other species. While these results are preliminary, our data suggest that the taxonomic circumscription of certain manzanita species may need to be reconsidered.

1 - University of California, Riverside, Botany and Plant Sciences, 900 University Ave, Riverside, CA, 92521
2 - Riverside, CA, United States
3 - University of California, Riverside, 900 University Ave, Riverside, CA, 92521, United States
4 - Plymouth State University, 17 High St, Plymouth, NH, 03264
5 - University of California, Santa Barbara, Santa Barbara, CA
6 - San Francisco State University, 1600 Holloway Ave, San Francisco, 94132, 94132
7 - USGS, Western Ecological Research Center, Sequoia Kings Canyon Field Station, 47050 Generals Hwy, Three Rivers, CA, 93271
8 - San Francisco State University, Biology, 1600 Holloway Avenue, Department Of Biology, San Francisco, CA, 94132, United States
9 - University Of California, Riverside, Botany And Plant Sciences, 900 University Avenue, Riverside, CA, 92521, United States

Keywords:
RADseq
California Floristic Province
species delimitation
Manzanita
ddRAdseq.

Presentation Type: Colloquium Presentations
Session: CO06, Ericaceae: Systematics, Ecology and Evolution
Location: Tucson D/Starr Pass
Date: Tuesday, July 30th, 2019
Time: 9:00 AM
Number: CO06005
Abstract ID:832
Candidate for Awards:Margaret Menzel Award,George R. Cooley Award