Opuscula Philolichenum, 11: 49-51. 2012. *pdf effectively published online 8 March 2012 via (http://sweetgum.nybg.org/philolichenum/)

Psora icterica (Lecanorales, ), a new and interesting disjunction from Alabama

1 2 CURTIS J. HANSEN * & LESLIE R. GOERTZEN

ABSTRACT. – icterica is reported new to Alabama growing on shallow sandy soil over granite flat rocks. This interesting disjunction further extends the range of this into the southeastern United States.

Psora icterica (Mont.) Müll. Arg. is a squamulose lichen easily recognized in the field by its rounded, concave to convex squamules with striking, bright yellow pigment (rhizocarpic acid) contrasted with dark red-brown to black, centrally located apothecia. For a full description of the species see Timdal (1986). While exploring large, granite flat rocks (fig. 1a) in north Auburn, Alabama (fig. 1b) our attention was drawn to a small yellow-green pigmented, squamulose lichen growing on thin sandy soil in shallow depressions over the granite surface (fig. 1c). Preliminary identification as Psora icterica was considered unlikely at first because Alabama is well out of range of the known distribution of this species. A careful reexamination of the specimen was undertaken and a duplicate sent to Larry St. Clair at Brigham Young University for verification. This is the first report of P. icterica in Alabama (Hansen 2003; Hansen & Dute 2005; Hansen & Lendemer 2008; Hansen et al. 2008) and extends the range of this species well into the southeastern United States east of the Mississippi River. As originally demarcated by Timdal (1986), and later followed by Brodo et al. (2001), Psora icterica was not known in the United States east of a line extending south from southwestern Minnesota to Brownsville, Texas, roughly the 97th meridian. Worldwide it has been collected on soils in arid, open habitats from deserts to conifer forests in North and South America (Brodo et al. 2001, Timdal 2002). Its occurrence has been well documented in the southwestern deserts and Intermountain West of the United States and in Baja California, Mexico (Brodo et al. 2001; Timdal 1986, 2002; St. Clair 1999). Lendemer (2008) reported new records of P. icterica from the central United States (Arkansas, Kansas, Missouri and Oklahoma) and several disjunct populations from the eastern United States (Maryland, New Jersey and Pennsylvania). Recently, this species was also collected in Georgia, where it was found growing in shallow gravel pans in association with Dermatocarpon luridum (With.) J. R. Laundon and intertwined with Placidium arboreum (Schwein. ex Tuck.) Lendemer (S. Beeching, pers comm.). This interesting range extension of Psora icterica into Alabama may not be entirely unexpected when considering the habitat in which it has otherwise been found in North America outside of its normal range. As discussed by Lendemer (2008), the eastern disjunct populations in Pennsylvania and Maryland were from unique serpentine barrens, known to support other disjunct lichen species and putative endemic vascular plants. At a microhabitat scale, these serpentine barrens may provide favorable arid microhabitats that create desert-like conditions in which P. icterica can grow. In like manner, granite flat rocks and outcrops found on the Piedmont Plateau, primarily from east Alabama through Georgia and into the Carolinas, also provide desert-like microhabitats that may be favorable for P. icterica to thrive. Like serpentine barrens, granite flat rocks are also home to a unique vascular plant flora including several

1 CURTIS J. HANSEN – Department of Biological Sciences, 101 Rouse Life Sciences Building, Auburn University, Auburn, AL 36849, U.S.A. – e-mail: [email protected] 2 LESLIE R. GOERTZEN – Department of Biological Sciences, 101 Rouse Life Sciences Building, Auburn University, Auburn, AL 36849, U.S.A. *=author for correspondence

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Figure 1, Psora icterica in Alabama (photos by the corresponding author). A, granite flat rock habitat of Psora icterica located in Auburn, Alabama. B, location of the collection site (red star) in Alabama. C, gross morphology of Psora icterica (C.J. Hansen 5097, scale = 5.0 mm).

50 uncommon endemics such as Diamorpha smallii Britt. ex Small, Phemeranthus mengesii (W. Wolf) Kiger, and Amphianthus pusillus Torr. While vast arid deserts characteristic of southwestern North America are not present in the eastern part of the continent, there are hundreds of desert-like microhabitats on rocky exposures, serpentine barrens, open rocky glades and elsewhere that may serve as habitable substrate for this enigmatic species. Additional searches for P. icterica in the arid microhabitats of the eastern United States will likely prove successful.

Specimens examined. – U.S.A. ALABAMA. LEE CO.: north of Lee County Road 72, north Auburn, 1 Jul 2011, on sandy soil over large exposed granite flat rock, C.J. Hansen 5097 (AUA, BRY).

ACKNOWLEDGEMENTS

We are grateful to Art Chappelka and Efrem Robbins for arranging access to the granite outcrop and to Larry St. Clair for confirming the identification of Psora icterica. In addition to his helpful review, we are grateful to Sean Beeching for permitting us to publish his report of P. icterica from Georgia. We thank Irwin Brodo for his constructive review and James Lendemer for his skillful editing. Ashley Peters is thanked for generating the map for figure 1b.

LITERATURE CITED

Brodo, I.M., S.D. Sharnoff and S. Sharnoff. 2001. of North America. Yale University Press, New Haven and London, pp. 795. Hansen, C.J. 2003. A catalog and brief history of the lichen flora of Alabama. Evansia, 20: 59-101. Hansen, C.J. and R.R. Dute. 2005. Additions to the lichen flora of Alabama. I. Evansia, 22: 110-117. Hansen, C.J. and J.C. Lendemer. 2008. A checklist of lichens collected during the 2007 Blomquist Foray in southern Alabama, U.S.A. Evansia, 25: 26-33. Hansen, C.J., J.C. Lendemer, and S. Beeching. 2008. Contributions to the lichen flora of Alabama: recent collections from four counties. Opuscula Philolichenum, 5: 43-48. St. Clair, L. 1999. A Color Guidebook to Common Rocky Mountain Lichens. M. L. Bean Life Science Museum, Brigham Young University, Provo, UT. 242 pp. Timdal, E. 1986. A revision of Psora (Lecidaeaceae) in North America. The Bryologist, 89: 253-275. Timdal, E. 2002. Psora. In: Nash III, T.H., Gries, C. and Bungartz, F. (eds.): Lichen Flora of the Greater Sonoran Desert Region, Vol. 1. Lichens Unlimited, Arizona State University, Tempe, AZ, pp. 418-430.

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