San Diego State University
Department of Biology

SDSU Herbarium


Email msimpson "at"






Mailing Address

Dr. Michael G. Simpson
Department of Biology
San Diego State University
San Diego, CA 92182-4614

B.S. : University of Florida
M.S. : University of North Carolina, Chapel Hill
Ph.D. : Duke University

General Research Interests: 
Plant systematics, plant taxonomy, floristics.

Recent Events!
Check out the video clip on SDSU Botany!

My field work in Chile and Argentina was supported in part by the National Geographic Society. I and my colleagues are working on the phylogenetic relationships of the Amsinckiinae (Boraginaceae), which occur in both North America and South America (a few in Australia), and not in the intervening tropics, and are termed American Amphitropically Disjunct plants. See my web page on Some Plants of Chile/Algunas Plantas de Chile.

Specific Research Interests
My research in plant systematics lab focuses on the systematics and evolution of land plants with three general objectives:
   1) to infer the phylogenetic relationships of plant groups and to use that pattern of evolutionary history to assess aspects of character evolution, biogeography, ecology, and evolutionary process;
   2) to investigate the delimitation of plant species and infraspecies, especially in evaluating rare/endangered taxa;
   3) to discover the plant species and community structure of regions in floristic studies.

Courses Taught at SDSU
Principles of Organismal Biology (Biology 204)
Economic Botany (Biology 460)
Plant Systematics (Biology 530)
Taxonomy of California Plants (Biology 531)

Current Projects
See the Plant Systematics at SDSU Web Page

See Plant Systematics Resources

Selected Publications (*=current or former students)

Chacón, J., F. Luebert, H. Hilger, S. Ovcinnikova, F. Selvi, L. Cecchi, C. M. Guilliams*, K. Hasenstab-Lehman*, K. K. Sutorý, M. G. Simpson, and M. Weigend. 2016. A revised infrafamilial classification of the borage family (Boraginaceae s.str.) based on a molecular phylogeny with an emphasis on the placement of some enigmatic genera. Taxon in press.

Luebert, F., L. Cecchi, M. W. Frohlich, M. Gottschling, C. M. Guilliams*, H. H. Hilger, K. E. Hasenstab-Lehman*, J. S. Miller, M. Mittelbach, M. Nazaire, M. Nepi, D. Nocentini, D. Ober, R. G. Olmstead, F. Selvi, M. G. Simpson, K. Sutorý, B. Valdés, G. K. Walden, and M. Weigend (BoraginalesWorkingGroup). 2016. Familial classification of the Boraginales. Taxon in press.

Mabry, M. E.*, R. A. Dowdy*, L. M. Simpson, J. P. Rebman, and M. G. Simpson. 2016. Taxonomy of the winged popcorn flower: Cryptantha pterocarya (Boraginaceae). Phytotaxa 253:97-130. (pdf)

Simpson, M. G.
, L. M. Simpson, and J. P. Rebman. 2016. A new, large-flowered variety of Eremocarya micrantha (Boraginaceae). Madroño 63:39-54 (pdf).

Benet-Pierce, N. and M. G. Simpson. 2014. The taxonomy of Chenopodium desiccatum and C. nitens, sp. nov. Journal of the Torrey Botanical Society 141:161-172. (pdf)

Rebman, J. P. and M. G. Simpson. 2014. Checklist of the Vascular Plants of San Diego County, 5th edition. San Diego Natural History Museum Publications. (pdf)

Ripma, L.*, M. G. Simpson, and K. Hasenstab-Lehman*. 2014. Geneious! Simplified genome skimming methods for phylogenetic systematic studies: A case study in Oreocarya (Boraginaceae). Applications in Plant Sciences doi: 10.3732/apps.1400062. (pdf)

Simpson, Michael G. 2014. Review of Intermountain Flora: Vascular Plants of the Intermountain West, U.S.A. Subclass Magnoliidae– Caryophyllidae, Vol. 2A. By N. H. Holmgren, P. K. Holmgren, J. L. Reveal, and collaborators. 2012. The New York Botanical Garden Press, Bronx, New York. 742 pp. ISBN 978-0-89327- 520-4, Price $150.00, hardcover.  Madroño 61: 146-147. (pdf)

Simpson, M. G., K. Hasenstab-Lehman*, and R. B. Kelley. 2014. Typification of the name Johnstonella (Boraginaceae). Taxon 63: 930-931. (pdf)

Simpson, M. G., R. Dowdy*, J. P. Rebman, R. B. Kelley, and L. M. Simpson. 2014. The recognition of two species in Eremocarya (Boraginaceae): Evidence from fornix bodies, nutlets, corolla size, and biogeography. Madroño 61: 259–275. (pdf)

Guilliams, C. M.*, B. A. Veno, M. G. Simpson, and R. B. Kelley. 2013. Pectocarya anisocarpa, a new species of Boraginaceae, and a revised key for the genus in western North America. Aliso 31: 1-13. (pdf)

Silveira, M.* and Simpson, M. G. 2013. Phylogenetic systematics of the mesa mints: Pogogyne (Lamiaceae). Systematic Botany 38: 782-794. (pdf)

Simpson, M. G., J. P. Rebman, K. E. Hasenstab-Lehman*, C. M. Guilliams*, and P. McConnell. 2013. Cryptantha wigginsii (Boraginaceae): A presumed extinct species rediscovered. Madroño 60(1): 24-34. (pdf)

Simpson, M. G. and J. P. Rebman. 2013. A new species of Cryptantha (Boraginaceae) from the Sierra de San Pedro Mártir, Baja California, Mexico. Madroño 60(1): 35-45. (pdf)

Yost, J. M., M. Bontrager, S. McCabe, D. Burton*, M. G. Simpson, K. M. Kay, and M. Ritter. 2013. Phylogenetic relationships and evolution in Dudleya (Crassulaceae). Systematic Botany 38: 1096-1104 (pdf).

Dodero, M. W.* and M. G. Simpson. 2012. Dudleya crassifolia (Crassulaceae), a new species from northern Baja California, Mexico. Madroño 59: 223-229. (pdf)

Hasenstab-Lehman, Kristen E.* and M. G. Simpson. 2012. Cat’s Eyes and Popcorn Flowers: Phylogenetic Systematics of the Genus Cryptantha s.l. (Boraginaceae). Systematic Botany 37: 738–757. (pdf)
   NOTE: Winner of the 2014 Grady Webster Award, given by the American Society of Plant Taxonomists, for best publication during the two year period 2012-2013!

Kelley, R. B., M. G. Simpson, and K. E. Hasenstab. 2012. Cryptantha. Pp. 455-468 in B. G. Baldwin, D. H. Goldman, D. J. Keil, R. Patterson, T. J. Rosatti, and D. H. Wilken (eds.), The Jepson Manual: Vascular Plants of California. Second Edition. University of California Press, Berkeley, Los Angeles, London.

Silveira, M., M. G. Simpson, and J. D. Jokerst. 2012. Pogogyne. Pp. 850-851 in B. G. Baldwin, D. H. Goldman, D. J. Keil, R. Patterson, T. J. Rosatti, and D. H. Wilken (eds.), The Jepson Manual: Vascular Plants of California. Second Edition. University of California Press, Berkeley, Los Angeles, London.

Guilliams, C. M.*, Simpson, M. G., and J. P. Rebman. 2011. Calyptridium parryi var. martirense (Montiaceae), a new taxon endemic to the Sierra San Pedro Mártir, Baja California, Mexico. Madroño 58(4): 258-266. (pdf)

Simpson, M. G., C. M. Guilliams*, and M. Silveira*. 2010. Taxonomy of Calyptridium parryi (Montiaceae). Madroño 57: 145-160. (pdf)

Benet-Pierce, N. and M. G. Simpson. 2010. Chenopodium littoreum (Chenopodiaceae),  a new goosefoot from dunes of south-central coastal California. Madroño 57: 64-72. (pdf)

Simpson, Michael G.  2010.  Plant Systematics, 2nd edition.  Elsevier-Academic Press. (web site)

Simpson, Michael G. and Kristen E. Hasenstab*. 2009. Cryptantha of Southern California. Crossosoma 35: 1-59. (pdf)

Pierce, Nuri and Michael G. Simpson. 2009. Polyaperturate pollen types and ratios of heteromorphism in the monocot genus Conostylis R. Br. (Haemodoraceae). Australian Systematic Botany 22: 16-30. (pdf)

Winner, Annette and Michael G. Simpson.  2007.  A new subspecies of Pentagramma triangularis (Pteridaceae).  Madroño 54(4): 345-353. (pdf)

Rebman, Jon P. and Michael G. Simpson.  2006.  Checklist of the Vascular Plants of San Diego County.  4th edition.  San Diego Natural History Museum, San Diego, California. 

Simpson, Michael G. 2006. Plant Systematics. Elsevier-Academic Press. (web site)
   NOTE: Winner of the Gleason Award, New York Botanical Garden, 2006!

Simpson, Michael G. and Darren H. Burton*.  2006.  Floral anatomy of the Pontederiaceae and its systematic significance.  Aliso 22: 499-519. In: Columbus, J. T., E. A. Friar, J. M. Porter, L. M. Prince, and M. G. Simpson [eds.].  Monocots:  Comparative biology and evolution.  2 vols.  Rancho Santa Ana Botanic Garden, Claremont, California, U. S. A. (pdf)

2003 and earlier
Lori Hargrove and Michael G. Simpson.  2003. Ultrastructure of heterocolpate pollen in Cryptantha (Boraginaceae).  International Journal of Plant Sciences 164(1): 137-151. (pdf)

Evans, Timothy M., Robert B. Faden, Michael G. Simpson, and Kenneth J. Sytsma.  2000.  Phylogenetic relationships in the Commelinaceae: I. A cladistic analysis of morphological data.  Systematic Botany 25: 668-691. (pdf)

Marsden, Kim L.* and Michael G. Simpson.  1999.  Eryngium pendletonensis (Apiaceae), a new species from southern california.  Madroño 46(1): 55-58. (pdf)

Simpson, Michael G.  1998.  Reversal in ovary position from inferior to superior in the Haemodoraceae: evidence from floral ontogeny.  International Journal of Plant Sciences 159(3): 466-479. (pdf)

Simpson, Michael G.  1998.  Haemodoraceae.  In: Kubitski, ed. Families and Genera of Flowering Plants.   Volume IV. Flowering Plants Monocotyledons. Alismatanae and Commelinanae (except Gramineae). Pp. 212-222. Springer, Berlin.

Simpson, Michael G. and Rudall, P.  1998.  Tecophilaeaceae.  In: Kubitski, ed. Families and Genera of Flowering Plants.   Volume III. Flowering Plants Monocotyledons. Lilianae (except Orchidaceae). Pp. 429-436. Springer, Berlin.

Simpson, Michael G.  and Levin, G. A.  1994.  Pollen ultrastructure of the biovulate Euphorbiaceae.  International Journal of Plant Sciences 155: 313-341. (pdf)

Levin, Geoffrey A., and Michael G. Simpson.  1994.  Phylogenetic implications of pollen ultrastructure in the Oldfieldioideae (Euphorbiaceae).  Annals of the Missouri Botanical Garden 81: 203-238. (pdf

Levin, Geoffrey A., and Michael G. Simpson.  1994.  Phylogenetic relationships of Hymenocardia and Didymocistus (Euphorbiaceae).  Annals of the Missouri Botanical Garden 81: 239-244. (pdf

Simpson, Michael G.  1993.  Septal nectary anatomy and phylogeny in the Haemodoraceae.  Systematic Botany 18: 593-613. (pdf)

Simpson, Michael G.  1990.  Phylogeny and classification of the Haemodoraceae.  Annals of the Missouri Botanical Garden 77: 722-784. (pdf)

Simpson, Michael G.  1989.  Pollen wall development of Xiphidium coeruleum (Haemodoraceae) and its systematic implications.  Annals of Botany 64: 257-269. (pdf)

Simpson, Michael G.  1988.  A critique of "Bromeliales, related monocots, and resolution of relationships among Bromeliaceae subfamilies."  Systematic Botany 13: 610-614. (pdf

Simpson, Michael G.  1988.  Embryological development of Lachnanthes caroliniana (Haemodoraceae).  Amer. J. Bot. 75: 1394-1408. (pdf)

Simpson, Michael G.  1987.  Pollen ultrastructure of the Pontederiaceae:  evidence for exine homology with the Haemodoraceae.  Grana 26: 113-126. (pdf)

Simpson, Michael G.  1985.  Pollen ultrastructure of the Tecophilaeaceae.  Grana 24: 77-92. (pdf)

Simpson, Michael G.  1985.  Pollen ultrastructure of the Philydraceae.  Grana 24: 23-31. (pdf)

Simpson, Michael G.  1983.  Pollen ultrastructure of the Haemodoraceae and its taxonomic significance.  Grana 22: 79-103. (pdf)

Simpson, Michael G. and W. C. Dickison.  1981.  Comparative anatomy of Lachnanthes and Lophiola (Haemodoraceae).  Flora 171: 95-113. (pdf)

Non-referred publications

Simpson, Michael G., E. Gergus, and S. C. McMillan.  2005.  Laboratory Manual for Organismal Biology: an Evolutionary Approach. 7th edition.  Rhynchops Press, San Diego, California.

Simpson, Michael G.  2013.  Plant Collecting and Documentation Field Notebook.  Rhynchops Press, San Diego, California.