Abstract Detail

Systematics

Hasenstab-Lehman, Kristen [1], Kok, Silas [2], Guilliams, C. Matt [1].

Investigating the origins of the California Island mallows (Malva; Malvaceae) using phylogenetic tools.

The islands off the Pacific Coast of Alta and Baja California represent a diverse range of ecosystems across a wide latitudinal gradient, and are well known for their endemic flora. Malva L. is a genus of 25-30 taxa with a cosmopolitan distribution. All Western North America taxa are island endemics, with no naturally occurring populations on the adjacent mainland. Species include Malva pacifica and M. assurgentiflora which are present on several islands off the coast of Baja and Alta California respectively. Malva lindsayi is a Guadalupe Island endemic, and M. occidentalis is present on Guadalupe Island with a disjunct population on the Coronado Islands. Malva assurgentiflora is prized for its beauty and used in the horticulture trade; however, the evolutionary history and biogeographic origins of this species and its local congeners are poorly understood. Ray’s early phylogenetic work suggests that these taxa represent a clade, but each taxon was represented by a single exemplar, and did not include a recently circumscribed taxon endemic to the Southern Channel Islands. Here, we generate new nrITS and matK sequences for 1-4 individuals of each of the recognized taxa, and use published sequences from across the genus to assess the origins of our island endemics, and timing of invasion of the California islands. Our analyses suggest that the local Malva taxa represent an island radiation with a single invasion from the Old World, and a subsequent long distance dispersal to Australia.

1 - Santa Barbara Botanic Garden, Department of Conservation and Research, 1200 Mission Canyon Road, Santa Barbara, CA, 93105, USA
2 - Westmont College, 995 La Paz Road, Santa Barbara, CA, 93108, USA

Keywords:
Malva
Lavatera
Malvaceae
Island diversification
Channel Islands.

Presentation Type: Poster
Session: P, Systematics Posters
Location: Arizona Ballroom/Starr Pass
Date: Monday, July 29th, 2019
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PSY006
Abstract ID:668
Candidate for Awards:None