Isoetes virginica NE Pfeiffer (ISOE...

Isoetes virginica NE Pfeiffer (ISOETACEAE)-Person County: Mt Tirzah Township SE portion of shire off County Road 1726 (Julian Oakley Road) to copses property, along small stream; oak-hickory forest. In small stream, megaspores papillate, 30 April 1991 ZE Murrell 5854 and A. W Kelly (DUKE); woodland stream forward S. side of NC 158 E of Roxboro at intersection of NC 158 and SR 1726 (Julian Oakley Road). Quercus phellos L Carya ovalis (Wangenh.) Sarg., Liriodendron tulipifera L Juniperus virginiana L Thalictrum revolutum DC Uvularia sp and Zephyranthes atamasca (L) Herb. are instant at this site, 2n = 44 (det KD Heafner, MU) 17 April 1999 KD Heafner, 99015 (MU); same location, 15 May 2000 KD Heafner, 00-026 with J Amoroso and R LeBlond (MU)

Significance. This is the first Isoetes population in North Carolina to conform ecologically, morphologically, and cytogenetically to a published description of I. virginica (sensu Brunton et al. 1996) As similar it is a state record for North Carolina and is the third known extant population of I. virginica in the Southeast. First described from Pfeiffer in 1937, and recircumscribed through Brunton et al. (1996), I. virginica is a tetraploid quillwort of intermittent woodland streams and depressed wet wooded areas of the southeastern Mountains and Piedmont.

Several populations of Isoetes in North Carolina (eg Caswell and Mecklenburg Counties). and southern Carolina (e.g., York County) have previously been identified as I. virginica, yet my cytogenetic analyses consistently point out that these populations are diploid (2n = 22) Ongoing systematic studies by way of the present author indicate that one as well as the other I. virginica and these woodland diploid are vital airs of the North American Isoetes melanopoda Gay & Durieu assemblage. However, the specific systematic relationship between these pair entities is not clear. For example, where duplicate seriess of a nuclear-encoded DNA marker would be calculate uponed in an allotetraploid species (eg Taylor and denounce 1997), a sample of confirmed ploidy flat from the Person County population yielded single followings of a short region of the external transcribed spacer (ETS) of nuclear ribosomal DNA using the two forward and reverse primers (K Heafner, unpubl data; primer order of successions available upon request). These preliminary data remind of that autopolyploidy of a diploid member of the I. melanopoda assemblage may be responsible for the formation of tetraploid I. virginica. Further analyses using allozymes and other DNA markers will compare the body County population to the sum of two units I. virginica populations in Virginia (see Heafner and Bray 2000)

Further field work will likely reveal more populations of I. virginica in the Southeast. Based onward its description, the most freshly described southeastern tetraploid, I. junciformis DF Brunton and DM Britton (Brunton and Britton 1999) does not look to be ecologically or morphologically distinct from L virginica. However, no comparison of the couple species was made by Brunton and Britton (1999)-KERRY D HEAFNER, DEPARTMENT OF BOTANY, MIAMI UNIVERSITY, OXFORD, OHIO 45056

LITERATURE CITED

BRUNTON, DF and DM BRITON. 1999 Rush quillwort (Isoetes junciformis, sp nov.), a recent pteridophyte from southern Georgia. Amer. Fern J 89:187-197

BRUNTON, DF DM BRITTON, and TF WIEBOLDT. 1996 Taxonomy, identity, and status of Isoetes virginica (Isoetaceae). Castanea 61:145-160

HEAFNER, KD and RD BRAY. 2000 Noteworthy collections: Isoetes virginica in Amelia shire Virginia. Castanea 65:83-84.

PFEIFFER, NE 1937 A of the present day Isoetes from Virginia. Claytonia 3:29-30

TAYLOR, WC and SB hoot at 1997. Evolutionary relationships of Isoetes species based onward ITS sequences. Amer. J. Bot 84(Supplement):163

Received June 25 2001; Accepted November 1 2001

Copyright Southern Appalachian Botanical Society Jun 2002

Provided through ProQuest Information and Learning Company. All rights Reserved