The Lomatium grayi complex (Apiaceae) of the western United States: a taxonomic revision based on morphometric, essential oil composition, and larva-host coevolution studies

  • Jason Andrew Alexander University of California, Berkeley, University and Jepson Herbaria
  • Wayne Whaley Utah Valley University, Department of Biology
  • Natalie Blain Utah Valley University, Department of Biology


The Lomatium grayi complex is morphologically diverse across it range. The type species of this complex, Lomatium grayi s.s., has been found to not be a host of the larvae of Papilio indra, while the other three morphotypes are larval-hosts. A fifteen character, morphometric analysis was conducted on 390 herbarium specimens from throughout the range of this species. PCA, MANOVA, CDA, and Tukey tests revealed that the majority of the characters in this dataset were significantly different between four regional morphotypes. As a result of the morphometric analysis, the morphotypes are herein proposed as four species. Two new species are proposed for populations of L. grayi in the Pacific Northwest. Lomatium papilioniferum is proposed for plants in California, western Idaho, northern Nevada, Oregon, and Washington. Lomatium klickitatense is proposed for populations of robust plants from western Klickitat County, Washington, and northern Hood River County, Oregon. Lomatium grayi var. depauperatum is elevated to a species. This leaves no infraspecific taxa within L. grayi s.s. A presence/absence phenetic analysis of combined essential oil data was inconclusive regarding the composition of L. grayi s.s., which was found to be more similar to Lomatium klickitatense and Lomatium depauperatum than other species of Lomatium. Taxonomic treatments for each of the four species in this complex are provided. A key to these species and the multiple species that have been commonly mistaken for L. grayi is also included.


Barneby, R.C. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard. 13:1–1188.

Beauchamp, P.S., E. Chea, J.G. Dimaano, V. Dev, B. Ly, A.E. Miranda, & W.H. Whaley. 2009. Essential oil composition of six Lomatium species attractive to indra swallowtail butterfly (Papilio indra): Principal component analysis against essential oil composition of Lomatium dissectum var. multifidum. J. Essent. Oil Res. 21:535–542.

Collin, G., H. Gagnon, A. St.-Gelais, & M. Turcotte. 2014. Composition of the essential oil and the hydrosol of the roots of Ligusticum porteri. Am. J. Essent. Oil. Nat. Prod. 3:4–10.

Coulter, J.M. & J.N. Rose. 1888. Revision of North American Umbelliferae. Wabash College, Crawfordsville, Indiana, U.S.A.

Coulter, J.M. & J.N. Rose. 1900. Monograph of the North American Umbelliferae. Contr. U.S. Natl. Herb. 7:1–256.

Coulter, J.M. & J.N. Rose. 1909. Supplement to the monograph of the North American Umbelliferae. Contr. U.S. Natl. Herb. 12:447–448.

Cronquist A., N.H. Holmgren, & P.K. Holmgren. 1997. Subclass Rosidae (except Fabales). Intermountain flora: Vascular plants of the Intermountain West, U.S.A. 3A:1–446.

Dev, V., B. Ly, A.E. Miranda, & W. Whaley. 2007. Composition of the essential oils of three varieties of Lomatium grayi (J.M. Coult & Rose) J.M. Coult & Rose. J. Essent. Oil Res. 19:244–248.

Dev, V., W.H. Whaley, S.R. Bailey, E. Chea, J.G. Dimaano, D.K. Jogani, B. Ly, & D. Eggett. 2010. Essential oil composition of nine Apiaceae species from western United States that attract female indra swallowtail butterfily (Papilio indra). Biochem. Syst. Ecol. 38:538–547.

Ellison, R.L. & J.N. Thompson. 1987. Variation in seed and seedling size: The effects of seed herbivores on Lomatium grayi (Umbelliferae). Oikos 49:269–280.

Jones, M.E. 1902. Contributions to western botany, No. 10. Contr. W. Bot. 10:1–90 + figures.

Jones, M.E. 1908. Contributions to western botany: New species and notes. Contr. W. Bot. 12:1–81.

Hammer, Ø., D.A.T Harper, & P.D. Ryan. 2001. PAST: Paleontological Statistics Software Package for Education and Data Analysis. Palaeontologia Electronica, 4, 9 p.

G. Iscan, T. Ozek, G. Ozek, A. Duran, & K.H.C. Baser. 2004. Essential oils of three species of Heracleum: anticandidal activity. Chem. Nat. Compd. 40: 544–547.

Marhold, K. 2011. Multivariate morphometrics and its application to monography at specific and infraspecific levels. In: T.F. Stuessy & H.W. Lack, eds. Monographic plant systematics: Fundamental assessment of plant biodiversity. A.R.G. Gantner Verlag K.G., Ruggell, Liechtenstein. Pp. 73–99.

Mastrogiuseppe, J.D., S.J. Gill, K.S. Simmons, & G.K. Brown. 1985. Morphologic and cytotaxonomic evauluation of Lomatium tuberosum (Apaiceae). Brittonia 37:252–260.

Mathias, M.E. 1938. A revision of the genus Lomatium. Ann. Missouri Bot. Gard. 25:225.

Nishida, R. 2005. Chemosensory basis of host recognition in butterflies – multi-component system of oviposition, stimulants, and deterrents. Chem. Senses 30:i293–i294.

Omernik, J.M. & G.E. Griffith. 2014. Ecoregions of the conterminous United States ? Evolution of a hierarchical spatial framework. Environm. Managem. 54:1249–1266. doi:10.1007/s00267-014-0364-1

Prudic, K.L., J.C. Oliver, & F.A.H. Sperling. 2007. The signal environment is more important than diet or chemical specialization in the evolution of warning coloration. Proc. Natl. Acad. Sci. U.S.A. 104:19381–19386;

Saitou, N. & M. Nei. 1987. The neighbor-joining method: A new method for reconstructing phylogenetic trees. Molec. Biol. Evol. 4:406–425.

Tiehm, A. 1985. Vascular plant types of Clarence King’s exploration of the fortieth parallel, 1867–1869. Brittonia 37:400–424.

U.S. Environmental Protection Agency. 2013. Level III and IV ecoregions of the continental United States: Corvallis, Oregon, U.S. EPA, National Health and Environmental Effects Research Laboratory, map scale 1:3,000,000.

Van Wassenhove, F., P. Dirinck, G. Vulsteke, & N. Schamp. 1990. Aromatic volatile composition of celery and celeriac cultivars. HortScience 25:556–559.

Watson, S. 1871. Botany. In: C. King. Report U.S. geological exploration of the fortieth parallel. 5:1–525. Government Printing Office, Washington, U.S.A.

Welsh, S.L. 1982. Utah plant types—Historical perspective 1840 to 1981—Annotated list and bibliography. Great Basin Naturalist 42:129–195.

How to Cite
Alexander, J. A., Whaley, W., & Blain, N. (2018). The Lomatium grayi complex (Apiaceae) of the western United States: a taxonomic revision based on morphometric, essential oil composition, and larva-host coevolution studies. Journal of the Botanical Research Institute of Texas, 12(2), 387-444. Retrieved from