Disjunct Populations of Isoetes macrospora in Southeastern Tennessee

1979 ◽  
Vol 69 (4) ◽  
pp. 97 ◽  
Author(s):  
W. Michael Dennis ◽  
A. Murray Evans ◽  
B. Eugene Wofford
Keyword(s):  
HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 479b-479
Author(s):  
James A. Schrader ◽  
William R. Graves

We are interested in the potential of seaside alder as a shrub or small tree for managed landscapes. This species has received little attention from horticulturists and occurs naturally only in small, disjunct populations in Maryland and southern Delaware (Delmarva Peninsula), northwestern Georgia, and south-central Oklahoma. Our objective is to optimize asexual (softwood cuttings and tissue culture) and sexual propagation of seaside alder while testing for differences in propagation success among populations. Terminal softwood cuttings collected 11 June 1997 (Delmarva) and 25 Aug. 1997 (Oklahoma) were treated with IBA at various concentrations and provided intermittent mist in a greenhouse for 10 weeks. Up to 44% rooting was achieved by using 1 g IBA/kg on cuttings from Delmarva; replication over time will be used to determine whether poorer rooting of cuttings from Oklahoma (maximum of 17% with 8 g IBA/kg) was due to genotypic effects or the time of collection. Strobili were collected during late 1997 from multiple plants in the three populations. Unstratified seed from Oklahoma showed from 40% to 76% germination after 21 days depending on the tree of origin. The only previous data of germination of unstratified seeds was a report of 5% to 20% for seeds from Delmarva, so provenance as well as stratification effects on germination are being evaluated.


2021 ◽  
Author(s):  
Francesco Cerasoli ◽  
Aurélien Besnard ◽  
Marc‐Antoine Marchand ◽  
Paola D'Alessandro ◽  
Mattia Iannella ◽  
...  

Botany ◽  
2013 ◽  
Vol 91 (9) ◽  
pp. 605-613 ◽  
Author(s):  
Claudia Ciotir ◽  
Chris Yesson ◽  
Joanna Freeland

Understanding the spatial distribution of genetic diversity and its evolutionary history is an essential part of developing effective biodiversity management plans. This may be particularly true when considering the value of peripheral or disjunct populations. Although conservation decisions are often made with reference to geopolitical boundaries, many policy-makers also consider global distributions, and therefore a species’ global status may temper its regional status. Many disjunct populations can be found in the Great Lakes region of North America, including those of Bartonia paniculata subsp. paniculata, a species that has been designated as threatened in Canada but globally secure. We compared chloroplast sequences between disjunct (Canada) and core (USA) populations of B. paniculata subsp. paniculata separated by 600 km, which is the minimum distance between disjunct and core populations in this subspecies. We found that although lineages within the disjunct populations shared a relatively recent common ancestor, the genetic divergence between plants from Ontario and New Jersey was substantially greater than expected for a consubspecific comparison. A coalescence-based analysis dated the most recent common ancestor of the Canadian and US populations at approximately 534 000 years ago with the lower confidence estimate at 226 000 years ago. This substantially predates the Last Glacial Maximum and suggests that disjunct and core populations have followed independent evolutionary trajectories throughout multiple glacial–interglacial cycles. Our findings provide important insight into the diverse processes that have resulted in numerous disjunct species in the Great Lakes region and highlight a need for additional work on Canadian B. paniculata subsp. paniculata taxonomy prior to a reevaluation of its conservation value.


Zootaxa ◽  
2021 ◽  
Vol 5032 (3) ◽  
pp. 431-441
Author(s):  
LUIZ FERNANDO CARMO ◽  
JULIANA ALVES ◽  
IURI R. DIAS ◽  
MIRCO SOLÉ ◽  
CAIO V. DE MIRA-MENDES ◽  
...  

The Neotropical tribe Sphaenorhynchini is composed of 15 recognized species commonly named as “lime treefrogs”. Gabohyla pauloalvini occurs in Atlantic Forest lowlands through the states of Bahia and Espírito Santo, Brazil. Based on field observation, literature review, and evaluation of audio files, we conclude that previous bioacoustic descriptions were erroneously assigned to G. pauloalvini. Here, we describe for the first time the advertisement call of G. pauloalvini from two disjunct populations. In addition, we provide new distribution records and an updated map for this species. The advertisement call of G. pauloalvini is composed of 1–5 closely spaced notes, with duration of 0.016–1.976 s, inter-note intervals of 0.340–1.25 s, and an average dominant frequency (= fundamental frequency) of 4966.0 Hz. Harmonics are visible in the spectrogram. Three new populations of G. pauloalvini have been recorded and extended the distribution by 60 km south. Nevertheless, G. pauloalvini is still known only from few localities. We highlight the importance of depositing audio recordings and specimens in scientific collections to promote systematics and natural history studies.  


Oryx ◽  
2014 ◽  
Vol 49 (3) ◽  
pp. 506-513 ◽  
Author(s):  
Stefan Michel ◽  
Tatjana Rosen Michel ◽  
Abdusattor Saidov ◽  
Khalil Karimov ◽  
Munavvar Alidodov ◽  
...  

AbstractHeptner's markhor Capra falconeri heptneri is an Endangered wild goat occurring in disjunct populations in southern Tajikistan, Afghanistan, Uzbekistan and Turkmenistan. Surveys to determine the total population in Tajikistan were conducted during February–April 2012. A total of 1,018 animals were observed. In most areas, which include state protected areas and family- and community-based conservancies, markhor populations are stable or increasing. Threats include illegal hunting, habitat degradation, competition with livestock and disease transmission. To motivate conservancies economically to protect markhor populations, trophy hunting should be permitted to accommodate the sustainable use of markhor, with revenues distributed in a transparent and equitably shared manner.


2021 ◽  
pp. 153-157
Author(s):  
Joanna Sumner ◽  
Margaret L. Haines ◽  
Peter Lawrence ◽  
Jenny Lawrence ◽  
Nick Clemann

The alpine she-oak skink Cyclodomorphus praealtus is a threatened alpine endemic lizard from the mainland of Australia. The species is previously known from disjunct populations in Kosciuszko National Park in New South Wales and three isolated localities in the Victorian Alps. The New South Wales and Victorian populations represent separate evolutionarily significant units. In 2011, a fourth Victorian population was discovered. We conducted a phylogenetic analysis and determined that the newly discovered population is discrete and may have been separated from other populations since the end of the last glacial maxima. This population requires separate management.


2000 ◽  
Vol 125 (1) ◽  
pp. 128-134 ◽  
Author(s):  
James A. Schrader ◽  
William R. Graves

Genotypic variation and horticultural potential of Alnus maritima [Marsh.] Nutt. (seaside alder), a large shrub or small tree found naturally in only three small, disjunct populations, have not been studied. We examined effects of population of origin and environment on seed germination and growth and morphology of seedlings. The first experiment showed that 6 weeks of cold stratification optimized germination of half-sibling seeds from Oklahoma at 73.2%. When this treatment was applied to multiple groups of half-siblings from all populations in a second experiment, seeds from Oklahoma had a higher germination percentage (55.0%) than seeds from Georgia (31.4%) and the Delmarva Peninsula (14.7%). In a third experiment, morphology and growth of multiple groups of half-siblings from all three populations were compared in one environment. Leaves of seedlings from Oklahoma were longer (12.8 cm) and more narrow (2.15 length to width ratio) than leaves of seedlings from Georgia (12.0 cm long; ratio = 1.76) and the Delmarva Peninsula (11.6 cm long; ratio = 1.86). Seedlings from Oklahoma and Georgia accumulated dry weight at higher rates (181 and 160 mg·d-1, respectively) than seedlings from Delmarva (130 mg·d-1), while seedlings from Oklahoma and Delmarva were more densely foliated (0.72 and 0.64 leaves and lateral shoots per centimeter of primary stem, respectively) than those from Georgia (0.46 per cm). These differences indicate genetic divergence among the three disjunct populations and the potential to exploit genetic variation to select horticulturally superior A. maritima for use in managed landscapes.


Zootaxa ◽  
2016 ◽  
Vol 4205 (5) ◽  
pp. 401 ◽  
Author(s):  
MARCO A. RIBEIRO-JÚNIOR ◽  
SILVANA AMARAL

We present distribution data of all Anguidae, Scincidae, and Teiidae lizards known from the Brazilian Amazonia, totaling 29 species-level taxa, belonging to 14 genera. This represents 11 more species-level taxa than previously reported for these families in this area. Data were based on literature and 46,806 specimens deposited in three North American and eight Brazilian museums, including the main collections harboring Amazonian material. Most species (~55%) are endemic to Amazonia. Except for Ameiva ameiva, that is present in several environments and domains, non-endemic species are either associated with open dry (semideciduous) forest or open vegetation (savanna) enclaves in Amazonia, occupying similar environments outside Amazonia, gallery forests within the Cerrado, or present disjunct populations in the Atlantic Forest. As a whole, six taxa are widespread in Amazonia, four are restricted to eastern Amazonia, four to western Amazonia, three to southwestern Amazonia, one to northern Amazonia, and seven to the southern peripheral portion of Amazonia. Besides, two species present apparently more restricted, unique distributions. Only three species have a distribution that is congruent with one of the areas of endemism (AE) recognized for other organisms (birds and primates), of which two occur in AE Guiana and one in AE Inambari. 


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