Davenport, L.J. 2010. Nature Journal. The University of Alabama Press, Tuscaloosa, Alabama. 235 pages. $24.95 pbk. (alkaline paper). ISBN 978-0-8173-5569-2.
Davenport, L.J. 2010. Nature Journal. The University of Alabama Press, Tuscaloosa, Alabama. 235 pages. $24.95 pbk. (alkaline paper). ISBN 978-0-8173-5569-2.
ABSTRACT Trillium (Melanthiaceae) is a highly diverse genus in the Southeast and includes many local endemics. Previous studies on Trillium in eastern North America identified significant genetic structure associated with limited seed dispersal and historical landscape barriers. In this study, genetic structure was examined in Trillium cuneatum and T. stamineum across Mississippi and western Alabama to look for further evidence that landscape features influence genetic structure at local scales. DNA sequence variation in the trnL intron and trnL-trnF intergenic region was examined across 12 populations of T. cuneatum and six populations of T. stamineum. Samples of Trillium ludovicianum and Trillium foetidissimum were included for comparison. Five and four haplotypes were discovered in T. cuneatum and T. stamineum, respectively, but most populations were fixed for a single haplotype. Haplotypes from T. cuneatum in southwestern Mississippi were also present in congeneric species. Significant geographic structure was found in both species, and divergent haplotypes found on either side of the Tombigbee and Black Warrior Rivers suggest barriers to gene flow in the study area. Strong population differentiation suggests that seed dispersal is limited in both species. Given the strong degree of genetic structure detected in both species and their preference of mesic forests, it is expected that both species will continue to diverge at local scales.
ABSTRACT Buellia sharpiana is described as new to science based on material from a single locality at the summit of Mt. LeConte in Great Smoky Mountains National Park in the southern Appalachian Mountains of eastern North America. The species is characterized by its ascospore size, thallus morphology, medullary I reaction, and the production of xanthones. Comparison is made to two morphologically similar species, B. ocellata (Flo¨ rke ex Flot.) Ko¨ rb. and B. jugorum (Arnold) Arnold.
ABSTRACT Trillium tennesseense is described as a newly discovered member of Trillium subgen. Phyllantherum. The new species resembles the recently described T. oostingii but differs from it by having a shorter ovary, relatively longer staminal filaments and stigmas, and crestedundulate stigmatic surfaces. A chromosome count of 2n ¼10 was obtained for it, which agrees with other members of the genus and subgenus. Sequence data from the nuclear ribosomal internal transcribed spacer and the plastid trnH-psbA spacer regions provided further evidence of the distinctiveness of T. tennesseense. A phylogeny estimate based on these markers is presented for T. subgen. Phyllantherum which agrees well with the major species groups that have been previously recognized in the subgenus. Trillium tennesseense and T. oostingii were placed in the molecularbased phylogeny in a clade with T. lancifolium and T. recurvatum, two species that formed a previously recognized species group. Trillium tennesseense is currently known only from three locations, all occurring on the Sevier Shale formation on the northwest slope of the southeastern extension of Bays Mountain in Hamblen and Hawkins Counties, Tennessee. Based on its rarity, T. tennesseense should be considered as globally rare and in need of protection.
Limnobium spongia (Bosc) Rich. ex Steud. (HYDROCHARITACEAE)—Shannon County: Ozark National Scenic Riverways, Current River
Arctostaphylos uva-ursi (L.) Spreng. (ERICACEAE)—
Hampshire County: Yellow Spring
ABSTRACT The Perdido River Forever Wild Tract (PRFWT) is a contiguous 7,365-ha property that was acquired through multiple purchases by the State of Alabama’s Forever Wild Program in December 2006. The PRFWT lies 48 km east-northeast of Mobile, Alabama, 56 km northwest of Pensacola, Florida, and is bound on the east by the Perdido River. The site is managed by the Alabama Department of Conservation and Natural Resources as a nature preserve and wildlife management/recreational area. An intensive floristic study of this area was conducted from October 2007 through June 2012. A total of 721 taxa (713 different species, including five hybrids) from 371 genera and 122 families were collected with 95 taxa representing county records. One state record species was also collected. Asteraceae was the most collected family, with 127 species. Poaceae, Fabaceae, and Cyperaceae were the next largest families with 74, 54, and 39 species, respectively. Quercus was the largest genus represented with 15 species. Eighty-four nonnative species were collected during the surveys. Plant collections were deposited at the Alabama Natural Heritage Section Herbarium (ALNHS) and Anniston Museum of Natural History/Jacksonville State University Herbarium (JSU), with replicates and duplicates deposited at the University of Alabama Herbarium (UNA), Auburn University Herbarium (AUA), and Troy University Herbarium (TROY).
ABSTRACT The Little River National Wildlife Refuge (6,070 ha) is located on thewest Gulf Coastal Plain in southeastern Oklahoma, a region of high plant diversity for the state. An inventory of the refuge yielded 708 taxa of vascular plants in 688 species, 410 genera, and 128 families. The largest families were the Asteraceae (n¼88 taxa), Poaceae (n¼76), Cyperaceae (n¼49), and Fabaceae (n¼44). Sixty-seven nonnative taxa were collected, representing 9.5% of the flora. Sixty-two taxa were present that are tracked by the Oklahoma Natural Heritage Inventory, including the Oklahoma endemic, Leavenworthia aurea var. aurea. In addition, we report the first Oklahoma collection of Polygonum glabrum.
ABSTRACT Byrsonima lucida (Mill.) DC is the only member of the tropical plant family Malpighiaceae native to North America, and is considered a threatened species by the state of Florida. In order to better conserve the remaining natural populations of B. lucida, we studied the breeding system of this species in natural and garden settings. We carried out floral biology and breeding system experiments over three flowering seasons from 2009–2012. We found that stigmas were receptive mostly during the first 2 d of flowering, but not in the final day. Self-pollination yielded few fruits and pollinator exclusion yielded no fruit set, indicating self-incompatibility and pollinator dependence in this species. Obligate outcrossing and complete dependence on a specialist bee pollinator make B. lucida’s small, fragmented populations vulnerable to extinction. Conservation measures should include protecting its specialized bee pollinator.
ABSTRACT Conservation of rare species often involves restoration efforts to enhance or expand existing populations, a critical step of which is seed germination. Seed germination can be especially problematic in riparian zones where habitat disturbance through flooding can be a regular and frequent event. Spiraea virginiana Britton, a riparian clonal shrub, is a rare species that is particularly susceptible to problems at the seed stage; it is generally assumed to lack effective seed recruitment, although seeds are sometimes observed in the field. Therefore, we examined the effects of growth substrate and cold stratification on the number of days required for seeds to germinate and overall seed germination success. Overall, total seed germination for S. virginiana was low at only 10% and cold stratification had a significant effect on the initiation of germination; as the number of days of cold stratification increased, the time necessary for seeds to germinate decreased. Although seedlings of S. virginiana have not been observed in nature, this study indicates that seeds can germinate and thus recruitment by seed is at least theoretically possible. We recommend that a seed germination protocol using sterile soil with cold (58C), stratification treatment of at least 30 d should be used in future propagation and restoration efforts.