Matt Guilliams, Ph.D.

Matt oversees the Clifton Smith Herbarium. His focus is the study of the flora of California.

Matt Guilliams, Ph.D., is a plant systematist and curator of the Clifton Smith Herbarium at Santa Barbara Botanic Garden. As a botanist/plant systematist, his overall focus is the study of the flora of California, which includes floristics, biodiversity description, inferring evolutionary patterns, and conservation genetics of rare plants. Guilliams earned his bachelor’s and master’s degrees in evolutionary biology from San Diego State University and his doctorate in integrative biology from University of California, Berkeley. He has been working as a botanist in the state since 1998. 

Research interests: botany, conservation genetics, evolutionary biology, floristics, herbarium curation, island biogeography, phylogenetics, taxonomy, Boraginaceae, community science, Dudleya, Montiaceae 

Publications

Guilliams, C.M., K. Hasenstab-Lehman, & B.G. Baldwin. 2020. Nomenclatural changes in western North American Amsinckiinae (Boraginaceae). Novon 28:51-59.


Yost, J.M., and 39 others, including C.M. Guilliams and G.A. Wahlert. 2020. The California Phenology Collections Network: using digital images to investigate phenological change in a biodiversity hotspot. Madroño 66(4): 130-141.

Hasenstab-Lehman, K. & C.M. Guilliams. 2020. Evaluating taxonomic circumscription in Dudleya cymosa and D. parva using high-throughput restriction-site associated DNA sequencing, with an emphasis on rare and potentially undescribed subspecies in the Santa Monica Mountains National Recreation Area. Santa Barbara Botanic Garden, Santa Barbara, California. 37 pages.

Hasenstab-Lehman, K., C.M. Guilliams, & E.A. Thomas. 2020. California Channel Islands Reference Library. Santa Barbara Botanic Garden, California. 21 pages.

Hasenstab-Lehman, K., C.M. Guilliams, R.R. Naesborg, & C. Richart. 2020. Biodiversity Conservation on San Nicolas Island. Ironwood 28(2): 4-7.

Guilliams, C.M. & K. Hasenstab-Lehman. 2020. High-throughput sequencing reveals a complicated evolutionary history between endangered Dudleya verityi, (Crassulaceae) and a widespread congener, D. lanceolata. Santa Barbara Botanic Garden, Santa Barbara, California. 45 pages.

Guilliams, C.M. & K. Hasenstab-Lehman. 2020. Naval Base Ventura County, San Nicolas Island Terrestrial Flora Program Draft Final Report: Developing Botanical Resources for U.S. Navy California Channel Islands: Specimen Processing and Imaging, and a Checklist for San Nicolas Island. Cooperative Agreement N62473-17-2-0005. Santa Barbara Botanic Garden, Santa Barbara, California. 61 pages.

Guilliams, C.M. & K. Hasenstab-Lehman. 2020. Checklist of the vascular flora of San Nicolas Island, California, Version 1. Originally published online May 1, 2020, updated continually thereafter. www.cch2.org

Guilliams, C.M. 2020. Gruvelia. For: The Flora of Oregon, Corvallis, OR.

Guilliams, C.M. 2020. Sonnea. For: The Flora of Oregon, Corvallis, OR.

Guilliams, C.M. and R.B. Kelley. 2020. Pectocarya. For: The Flora of Oregon, Corvallis, OR.

Guilliams, C.M., K.E. Hasenstab-Lehman, and R. Kelley. 2020. Amsinckiopsis. For: The Flora of Oregon, Corvallis, OR.

Guilliams, C.M., K.E. Hasenstab-Lehman, and R. Kelley. 2020. Plagiobothrys. For: The Flora of Oregon, Corvallis, OR.

Schlising, R., E. Gottschalk Fisher, C.M. Guilliams, & B. Castro eds. 2019. Vernal Pool Landscapes: Past, Present, and Future. Studies from the Herbarium, Number 20, California State University, Chico.

Escudero, N., J. Gasca-Pineda, R. Bello, C.M. Guilliams, & M.C. Arteaga 2019. Genetic and phenotypic diversity of Branchinecta sandiegonensis in the vernal pools of Baja California, México. Zootaxa 4646(1): 145-163.

Guilliams, C.M. 2019. Reconsidering northern and southern taxa of island mallow (Malva assurgentiflora, Malvaceae) and their conservation status on the California Channel Islands. Phytoneuron, 2019-43: 1-13.

Guilliams, C.M., K. Hasenstab-Lehman, & A.J. Searcy. Winter 2019/2020. Community scientists use iNaturalist to map the distribution of a weed on-the-move: Urospermum picroides (Asteraceae). Dispatch, Cal-IPC Newsletter 27(3): 4-5.

Hasenstab-Lehman, K.E. & C.M. Guilliams. 2019. Draft report on the conservation genetics of beach spectaclepod (Dithyrea maritima (Davison) Davison; Brassicaceae). Unpublished report submitted to the California Department of Fish and Wildlife.

Carter, B.E., W.F. Hoyer, III, J. Dunn, S. Junak, & C.M. Guilliams 2018. New additions to the flora of San Nicolas Island, Ventura County, California. Aliso 36: 1-6.

Carter, B.E. & C.M. Guilliams 2018. Biogeographic patterns among seed-bearing and spore-bearing plants across the California Channel Islands. Western North American Naturalist 78(4): 699-710.

Randall, J.R., K.McEachern, J. Knapp, P. Power, S. Junak, K. Gill, D. Knapp, & M. Guilliams. 2018. Informing our successors: What botanical information for Santa Cruz Island will researchers and conservation managers in the century ahead need the most? Western North American Naturalist 78(4): 888-901.

Guilliams, C.M. 2018. Naval Base Ventura County, San Nicolas Island Erosion Control Program Final Report: Results of surveys for Dithyrea maritima on San Nicolas Island. Cooperative Agreement Number N62473-14-2-00015. Unpublished report. Santa Barbara, California.

Guilliams, C.M., A.I. Hernandez, & K. Hasenstab-Lehman. 2018. Naval Base Ventura County, San Nicolas Island Erosion Control Program Final Report: Population genetic study of island mallow (Malva assurgentiflora) across the Channel Islands archipelago to assess provenance of plants from San Nicolas Island. Cooperative Agreement Number N62473-14-2-00015. Unpublished report. Santa Barbara, California.

Schneider, H.E., S.E. Termondt, & C.M. Guilliams. 2018. Rare plant surveys and conservation seed collections in the California Floristic Province in Baja California, Mexico final report. Unpublished report, Santa Barbara Botanic Garden. 13 pp.

Riley, J. with contributions by S. Alfaro, M.C. Arteaga, C.M. Guilliams, K.E. Hasenstab-Lehman, A. Garcia Peralta, & J. Simancas. 2017. A Field Guide to the Vernal Pools of Baja California, Mexico. Jardín Botanico de San Quintín, San Quintín.

Carlquist, S. & C.M. Guilliams 2017. Distinctive wood anatomy of the root-parasitic family Lennoaceae (Boraginales). IAWA Journal 38 (1): 3-12.

Guilliams, C.M., K.E. Hasenstab-Lehman, M. Mabry, & M.G. Simpson 2017. Memoirs of a frequent flier: phylogenomics reveals 18 long-distance dispersals in the popcorn flowers (Amsinckiinae, Boraginaceae). American Journal of Botany, Special Issue on American Amphitropical Disjunction, 104: 1717-1728.

Simpson, M.G., C.M. Guilliams, K.E. Hasenstab-Lehman, M. Mabry, & L. Ripma 2017. Phylogeny of the popcorn flowers: Use of genome skimming to evaluate monophyly and interrelationships in subtribe Amsinckiinae (Boraginaceae). Taxon 66 (6): 1406-1420.

Simpson, M.G., L. Johnson, T. Villaverde, & C.M. Guilliams 2017. American amphitropical disjunct plants: insights and recent evidence. American Journal of Botany, Special Issue on American Amphitropical Disjunction, 104: 1600-1650.

Simpson, M.G., C.M. Guilliams, & L. Johnson 2017. Patterns and processes of American amphitropical disjunctions: new insights. American Journal of Botany, Special Issue on American Amphitropical Disjunction, 104: 1597-1599.

Guilliams, C.M., B.E. Carter, M.L. Ceceña Sánchez, J. Delgadillo, B. Holzman, S. Junak, D. Knapp, L.L. Mendoza, & S. Vanderplank. 2017. The remarkable flora of California Islands. Fremontia 45(3): 5-11. https://grownatives.cnps.org/2017/12/07/islands-of-the-californias/.

Schlising, R., E. Gottschalk Fisher, & C.M. Guilliams eds. 2016. Vernal Pools in Changing Landscapes. Studies from the Herbarium, Number 18, California State University, Chico.

Chacón, J., F. Luebert, H. Hilger, S. Ovchinnikova, F. Selvi, L. Cecchi, C.M. Guilliams, K. Hasenstab-Lehman, K. Sutorý, M.G. Simpson, & M. Weigend 2016. The borage family (Boraginaceae s.str.): A revised infrafamilial classification based on new phylogenetic evidence, with emphasis on the placement of some enigmatic genera. Taxon 65 (3): 523-546.

Dvorak, T.M, A. Catalano, & C.M. Guilliams. 2016. Monitoring within non-native ungulate enclosures documents the inherent size of Crocanthenum greenei (Cistaceae). Phytokeys 70: 11-16 (doi; 10.3897/phytokeys.70.9363).

Guilliams, C.M., K. Hasenstab-Lehman, José Delgadillo, & B.G. Baldwin 2016. Vernal pool landscapes of Baja California, México: an on-going project to assess vernal pool loss and protect what remains. Studies from the Herbarium, Number 18, California State University, Chico.

Guilliams, C.M., T. Jang, & B.G. Baldwin 2016. Molecular and morphological evidence for recognition of two species within Harpagonella (Amsinckiinae, Boraginaceae). Phytokeys 70: 17-30 (doi: 10.3897/phytokeys.70.9053).

Luebert, F., L. Cecchi, M.W. Frohlich, M. Gottschling, C.M. Guilliams, K.E. Hasenstab-Lehman & 15 others 2016. Familial classification of the Boraginales. Taxon 65 (3): 502-522.

Schneider, A.C., W.A. Freyman, C.M. Guilliams, Y.P. Springer, & B.G. Baldwin 2016. Pleistocene radiation of the serpentine-adapted genus Hesperolinon and other divergence times in Linaceae (Malpighiales). American Journal of Botany 103: 221-232.

Guilliams, C.M. 2016. Madroño Vol. 63 Dedication to Michael G. Simpson. Madroño 63(1): 1-2.

Wilken, D. 2016. Rarity, threats, and the conservation status of California geophytes. Fremontia 44: 20-26.

Felger, R.S., S. Rutman, C.M. Guilliams, & J. Malusa 2015. Ajo Peak to Tinajas Altas: Flora of Southwestern Arizona: Part 10, Eudicots: Berberidaceae, Bignoniaceae, and Boraginaceae. Phytoneuron 2015-1: 1-60.

Guilliams, C.M. 2015. The Lichens of the Channel Islands: new book project uses Garden herbarium. Ironwood 23 (2): 3.

Guilliams, C.M. 2015. The Flora of Santa Catalina Island: A partnership between the Santa Barbara Botanic Garden and the Catalina Island Conservancy. Ironwood 22 (4): 4-5.

Guilliams, C.M. & J.M. Miller 2014. Calandrinia, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=16615, accessed on Dec 23 2014.

Guilliams, C.M. & J.M. Miller 2014. Calyptridium, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=16845, accessed on Dec 23 2014.

Corona, G., C.M. Guilliams & S. Vanderplank 2014. Evaluación del riesgo de extinción de Centromadia perennis Greene de acuerdo al numeral 5.7 de la NOM-059-SEMARNAT-2010. Prepared for Sociedad de Plantas Nativas de Baja California. 17 pages.

Corona, G., C.M. Guilliams & S. Vanderplank 2014. Evaluación del riesgo de extinción de Adenothamnus validus (Brandegee) D.D. Keck de acuerdo al numeral 5.7 de la NOM-059-SEMARNAT-2010. Prepared for Sociedad de Plantas Nativas de Baja California. 20 pages.

Corona, G., C.M. Guilliams & S. Vanderplank 2014. Evaluación del riesgo de extinción de Chenopodium flabellifolium Standley de acuerdo al numeral 5.7 de la NOM-059-SEMARNAT-2010. Prepared for Sociedad de Plantas Nativas de Baja California. 21 pages.

Corona, G., C.M. Guilliams & S. Vanderplank 2014. Evaluación del riesgo de extinción de Dudleya anthonyi Rose de acuerdo al numeral 5.7 de la NOM-059-SEMARNAT-2010. Prepared for Sociedad de Plantas Nativas de Baja California. 21 pages.

Corona, G., C.M. Guilliams & S. Vanderplank 2014. Evaluación del riesgo de extinción de Eryngium aristulatum Jeps. var. parishii (J.M. Coult. y Rose) Mathias y Constance de acuerdo al numeral 5.7 de la NOM-059-SEMARNAT-2010. Prepared for Sociedad de Plantas Nativas de Baja California. 24 pages.

Corona, G., C.M. Guilliams & S. Vanderplank 2014. Evaluación del riesgo de extinción de Navarretia fossalis Moran, de acuerdo al numeral 5.7 de la NOM-059-SEMARNAT-2010. Prepared for Sociedad de Plantas Nativas de Baja California. 24 pages.

Plant Systematist & Curator of the Clifton Smith Herbarium