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NEW COMBINATION EURYBIA IN FROM NORTH AMERICA (ASTERACEAE: ASTEREAE) en biologie vegetale CANADA, H Quebec, •I, ABSTRACT m mfraspecific taxon Eu rybia from I ION Nesom The North American genus Euryhia, segregated from Aster by (1994), has now been shown convincingly be distmct from the Eurasian Aster to s.str & & (Noyes Rieseberg 1999; Brouillet et al. 2001a, b; Bastien Brouillet 2002; Nesom combmations Semple 2002). (1994, 1997) provided most of the et al. needed in this genus. Nevertheless, during preparation of the treatments of this genus for the Flora of North America project, differences in taxonomic con- Nesom me new com- cepts from those suggested by (1994) have led to propose a bmation. Nesom Eurybia glauca (Nutt.) G.L. In his taxonomy of Euryhia, Nesom (1994) recognized Euryhia pukhra (S.F. Nesom Nesom, from Euryhia glauca Blake) G.L. as a species distinct (Nutt.) G.L. justifying by the smaller leaves, more acute phyllaries and glandularity Yet, it except glandularity, which does not appear to vary gradually from one taxon for to the other, the other features all within the range encountered in E. glauca, fit apart from a slight tendency toward larger reproductive features in E. pulchra; when leaf size ranges overlap considerably a large sample of E. glauca is con- A morphometric study would be needed determine the exact ampli- sidered. to The and between two ranges tude significance of size differences the taxa. of m with the two taxa appear to be parapatric southern Utah-northern Arizona, Grand Canyon while E.glauca ranges E.pulchra restricted to the vicinity of the Rocky must widely to the north and east into the Southern Mountains; it be has been reported The restricted range and distmcf glandularity justify that E. Nesom io)ustilyrecogniznig/f hru as a distinct species agree with (1994) /Mile I puhhra that the inclusion by Cronquist (1994) of within wasatchensis E. E. is misguided as based only on the shared possession of glands. Several char- it is and acters distinguish pulchra E.wasatchcnsi^, including glaucousness E. leaf and phyllary habit (appressed vs squarrose), which the former shares with E. ^kiuca. Therefore, prefer to recognize the former as a variety of the as latter, is I done by Welsh even though was et (1987), originally described as a sub- al. it Nesom Eurybia glauca (Nutt.) G.L. var. glauca Nesom Eurybia glauca (Nutt.) G.L. var. pulchra (S.F. Blake) Brouillet, comb, et nov Basionym: Stat, AsicrgknicodesS.F. Blake subsp. pulcherS.F. Blake, Proc. Biol. Washington Eu pukh Nesom, Soc. 35:174. 1922. rybia ra Blake) G.L. Phytologia (S.F. 77:261. 1994. & The combination Aster glaucodes Blake pukher (Blake) Kearney var. Peebles, m Welsh reported et (1987), not valid because Kearney and Peebles (1960) al. is make did not a formal status change with proper reference to the basionym. name was fhc thus never validly published at the varietal rank. These author unwittingly |XM-haps referred to the infraspecific taxon as a variety instead of a subspecies and might not intended make new combination. ha\'e to a The origin glandularity E.glauca pulchra and of in var. E. wasatchensis, as compared to the eglandular E.glauca var.glauca, could be explained by consid- members which ering the other of section Herrickia, to these taxa clearly be- & long: Euryhia horrida (Wooton Standi.) G.L. Nesom (formerly Herrickia horrida) and Aster hingu members (Brouillet et 2001a, All of section al. b). Hcrrichiii are glandular except E.^/taat) var.g/auca. more parsimonious to It is explain the lack ol glands in the latter by a loss of glands after speciation. This hypothesis would imply that the presenceof glands in pulchra ancestral var. is may within the species, and that var. glauca represent a relatively more recent expansion of an eglandular phenotype to the range of the species as known from more today, a restricted original area perhaps close to the San Juan river ACKNOWLEDGMENTS Guy Nesom would thank like to L. (Botanical Research Institute of Texas) and I NSERC (Canada). cpDNa and combined ITS-cpDNA sequence Botany 2002 Meet- using data. ing, Madison, Wl, Aug, 2-7, 2002. Abstract 636, 62. p. 1 and phylogeny American Brouillet, L.,G.A. Allen, J.C.Sfmple, M. Iio.2001a. ITS of Nortl-i asters (Asteraceae: Astereae): basal grade to North American lineages and distinct from Eur- CBA/ABC June 23-27, 2001 asian ones. Meeting,. Kelowna, 31 (abstract). B.C., p. . and M. 2001 phylogeny of North American Brouillet, L, G.A. Allen, J.C. Semple, Itg. b. ITS as- (Asteraceae; Astereae). Botany 2001 Meeting, .AIbuquerque,NM, Aug. 12- 2001, ters 16, Holmgren, Holmgren, Cronouist, a. 994. Aste rales. Vol. 5. In: A. Cronquist, A.H. N.H. J.L. Re- 1 New and Holmgren, Intermountain York Botanical Garden, Bronx. veal, eds., flora. P.K, and Kearney, T.H. and R.H. Peebles. 960. Arizona flora. Univ. California Press, Berkeley Los 1 Nesom, G.L. 994. Review of the taxonomy of Aster sensu lato (Asteraceae: Astereae), em- 1 New phasizing the World species. Phytologia 77:141-297. NoYES, R.and LH. Rieseberg. 999. ITS sequence data support a single origin for North Ameri- 1 and deep geographic Amer. can Astereae (Asteraceae) reflect division in Aster Bot, s.l. J. Semple, J.C, S.B. Heard, and L. Brouillet. 2002. Cultivated and native Asters of Ontario Waterloo (Compositae: Astereae). Univ. Series 41, Biol, A Welsh, S,L.,N.D.Atwood,L.C.Higgins, and S.Goodrich. 1987. Utah Great Basin Natural- flora.