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Pseudophoenix ekmanii is a threatened palm species endemic to the Dominican Republic. Sap from trees is extracted to make a local drink; once they are tapped the individual usually dies. Plants are also illegally harvested for the nursery trade and destroyed by poachers hunting the endemic and threatened Hispaniolan parrot. We used 7 DNA microsatellite markers to assist land managers in developing conservation strategies for this palm. We sampled 4 populations along the known distribution range of this species (3 populations from the mainland and 1 from the small island of Isla Beata), for a total sample of n = 104. We found strong evidence for genetic drift, inbreeding, and moderate gene flow (i.e., all populations had at least 4 loci that were not in Hardy-Weinberg equilibrium, at least 9 loci pairs were in linkage disequilibrium, the pairwise F(ST) values ranged from 0.069 to 0.266, and had positive F(IS) values). Data supported an isolation-by-distance model, and cluster analyses based on genetic distances resolved 2 groups that match a north-south split. The population from Isla Beata had the lowest levels of genetic diversity and was the only one in which we found pairs of individuals with identical shared multilocus genotypes.

Guangdong Province, located in southern China, is of great interest in studies of plant geography and conservation in limestone areas because of its rich biodiversity. We: (1) performed a phytogeographical analysis of pteridophytes in the limestone areas in Guangdong, (2) evaluated and determined levels of endemism, and (3) identified affinities with the floras of neighboring limestone areas. We found that some families show a preference for limestone habitats, e.g., Hypodematiaceae, Lygodiaceae, and Adiantaceae, are typical elements among pteridophytes in the limestone regions of Guangdong. In addition, some genera or section, such as Hypodematium, and Polystichum sect. Cyrtogonellum, show an exclusive preference for limestone habitats. The predominant phytogeographical affinities identified were East Asia, Chinese endemic, and Tropical Asia. We concluded that: (1) the limestone fern flora of Guangdong is principally subtropical in nature and represents southern subtropical flora at the margins of the northern tropics, with a strong interaction with the East Asian flora, (2) the limestone fern flora of Guangdong has a phytogeographical affinity with Japan, though the floras of neighboring Guangxi and Hainan Provinces have higher similarity with it.

Neolaugeria (Rubiaceae) comprises three species of woody shrubs and trees that are endemic to the West Indies. A molecular phylogeny was constructed using nucleotide sequences of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA to elucidate the evolutionary history of the genus. The data support the monophyly of Neolaugeria and a relatively distant relationship to Stenostomum, a genus that Neolaugeria has variously been merged into as a section. Constraint analyses indicate that Neolaugeria resinosa may occupy a more basal position, supporting a pattern of speciation and colonization in a northwesterly direction from the Lesser Antilles to the Greater Antilles and the Bahamas.

Dioon edule (Zamiaceae) is an endemic Mexican cycad. Nineteen microsatellite loci were isolated from three enriched genomic libraries of D. edule var. angustifolium, D. tomasellii, and D. caputoi. Seven of these loci showed polymorphisms in D. edule. Levels of polymorphism were assessed using 16 individuals from each of seven populations throughout the range of this species. The number of alleles per locus ranged from two to five and the observed and expected heterozygosities ranged from 0.0 to 0.9821 and from 0.0088 to 0.6318, respectively. All loci show significant linkage disequilibrium. Three loci depart significantly from Hardy–Weinberg equilibrium.