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Premise of the study Understanding the underlying mechanisms for the evolution of intercontinental disjunct patterns has long fascinated botanists. We present a molecular phylogenetic reconstruction of Maianthemum s.l. (including Smilacina) with a focus on Maianthemum s.s. species, which have a disjunct distribution between Eurasia and North America. Within this evolutionary framework, we clarify the systematic classification and biogeographical history of Maianthemum s.s. Method Data from two nuclear and five chloroplast DNA regions were analyzed using the programs PAUP*, RAxML, MrBayes, BEAST, and RASP. Key results Our molecular phylogeny supports Maianthemum s.s. as monophyletic. Maianthemum bifolium and M. canadense are grouped according to their taxonomic species, but the accessions of M. dilatatum are divided into two well-defined groups, i.e., one comprising western North American accessions, and the other composed of northeast Asian accessions. Molecular dating and biogeographic reconstructions suggest a northeast Asian origin for Maianthemum s.s. and that a complicated pattern of divergent evolution began approximately in the late Miocene. Intercontinental disjunctions of Maianthemum s.s. in the Northern Hemisphere appear to have occurred two times during the Pliocene. Conclusions Based on our results, two possible ways to treat Maianthemum s.s. species can be envisioned: (1) elevate Asian populations of M. dilatatum to specific rank; or (2) combine the three Maianthemum s.s. species into a broadly defined single species. We recommend treatment of Maianthemum s.s. as a single species. The biogeographic patterns of Maianthemum s.s. coupled with molecular dating suggest both vicariance and long-distance dispersal events as key mechanisms for diversification of the clade.

This study examines phylogenetic relationships among the 12 genera of Urticeae (Urticaceae) and investigates the pattern of morphological evolution based on analysis of nuclear ribosomal internal transcribed spacer (nrITS) and two plastid DNA regions (rbcL exon, trnL-F spacer). Sequence data were analyzed using maximum parsimony and Bayesian inference, and selected morphological traits were mapped onto the molecular tree. The molecular results strongly supported monophyly of Urticeae, excluding Gyrotaenia, which is related to Elatostemateae. All genera were monophyletic except for Urtica, Laportea, and Urera. Two Hesperocnide species are nested within Urtica. Laportea and Urera are divided into three groups with a strong geographical signal. The inferred phylogeny indicates five well-supported clades in Urticeae: clade A including Urtica (with Hesperocnide), Zhengyia, Laportea I, and Nanocnide; clade B comprising Dendrocnide and Discocnide; clade C including only Girardinia; clade D including Laportea II; and clade E including Obetia, Urera I, II, III, and Poikilospermum. Although it is difficult to identify morphological synapomorphies for these well-defined clades within Urticeae, character analysis shows that the herbaceous habit and alternate leaves are the ancestral states in the tribe. The presence of stinging hairs is the derived status in Urticeae, and it might have been a key innovation triggering species diversification in the tribe.

It has been suggested that many plants now found in the arctic originated from ancestors that occurred at high altitudes in the southern mountains of the Northern Hemisphere during the Tertiary. However, this hypothesis has rarely been tested using a molecular phylogenetic approach. Here, we present a fossil-calibrated molecular phylogeny of Lagotis, an arctic-alpine genus with the greatest diversity in the Qinghai-Tibetan Plateau (QTP) and Central Asian mountains, based on five chloroplast (matK, psbA-trnH, rps16, trnG-S, trnL-F) and nuclear ribosomal ITS DNA markers. Within this framework, we infer the ancestral area and biogeographic history of the genus. Four major clades (A D) within Lagotis were recovered with strong support, which largely correspond to the previous classification of the genus. Within clade A, Lagotis species from QTP were distributed among several subclades, and L. integrifolia from Central Asia was sister to L. glauca and L. minor from the arctic and subarctic region. The Bayesian molecular dating and the ancestral area reconstruction analyses suggested that Lagotis could have originated in the QTP in the Miocene (Tertiary), and that the genus radiated from the Miocene to Pleistocene. The diversification of Lagotis probably took place predominantly in the QTP and it subsequently spread to the Central Asian highlands, followed by northward migration into the arctic. Our results support the hypothesis that the "Central Asiatic Highland Corridor" as an important route for the migration of the flora between the arctic and QTP.

Zhengyia shennongensis is described here as a new genus and species of the nettle family (Urticaceae) from Hubei province, central China. The phylogenetic position of Z. shennongensis is determined using DNA sequences of nuclear ribosomal ITS and three plastid regions (rbcL, psbA-trnH, trnL-F). Zhengyia shennongensis is readily distinguished from the related genera Urtica, Hesperocnide, and Laportea in the tribe Urticeae by its seed (oblong-globose or subglobose and not compressed achenes, surface densely covered with nipple-shaped protuberances) and stipule morphology (large leaf-like stipules with auriculate and amplexicaulous base and united with stem). Phylogenetic evidence indicates that Zhengyia is a distinct group related to Urtica (including Hesperocnide) species and Laportea cuspidata in tribe Urticeae. The bulbiliferous species of the tribe (L. bulbifera, L. cztspidata, Z. shennongensis) do not form a clade. This result indicates that the bulbil trait evolved in parallel within Urticeae. Our findings highlight the importance of shady and moist habitats in promoting species diversification and the parallel evolution of morphological traits that are likely to be adaptive.

Species identification and analysis of phylogenetic relationships within the genus Typha are difficult because of the high degree of variability among morphological characters and frequent interspecific hybridization. Traditionally, two sections (T. sect. Ebracteolatae and sect. Bracteolatae) have been recognized within the genus based on the presence or absence of bracteoles in the female flowers. The aims of this study were to reconstruct the phylogeny of Typha using DNA sequence data from nuclear LEAFY and three plastid regions, and to evaluate previous classifications. We sampled nine species from various regions that were each invariant at the molecular level. A parsimony consensus tree recovered three clades in the genus: clade I including T. angustifolia, T. elephantina, T. domingensis, and T. capensis; clade II including T. orientalis and T. laxmunni; and clade III comprising T. latifolia and T. shuttleworthii. Typha minima was found sister to the rest of the Typha species with maximal bootstrap support. The results do not support previous classifications of Typha. Character analysis showed that bracteole loss, spatulate stigma, lack of a gap between staminate and pistillate inflorescences, and monad pollen are derived characteristics in Typha.

 Premise of the study: Two marker systems were developed for the molecular identifi cation of three Trapa species based on the length variation of nuclear AP2 and trnL-F chloroplast intergenic spacer region.  Methods and Results: Our marker systems analyzed 118 individuals among 36 populations from three Trapa species. Trapa incisa was found to have a unique genotype from the other two species. Individuals of T. bispinosa were distinguished from T. japonica because the former had only a single AP2 genotype. Moreover, our results suggest a hybrid status of T. japonica in terms of two bands within an individual. One band was specifi c to T. japonica and the other one shared with T. bispinosa .  Conclusions: Our marker system demonstrates that nucleotide sequence variations can serve as a fast, reliable, and reproducible tool for molecular genotyping and examining the natural hybrid of water chestnut species.

In this paper, we first investigate the side channel analysis attack resistance of various FPGA hardware implementations of the ARIA block cipher. The analysis is performed on an FPGA test board dedicated to side channel attacks. Our results show that an unprotected implementation of ARIA allows one to recover the secret key with a low number of power or electromagnetic measurements. We also present a masking countermeasure and analyze its second-order side channel resistance by using various suitable preprocessing functions. Our experimental results clearly confirm that second-order differential side channel analysis attacks also remain a practical threat for masked hardware implementations of ARIA.

Premise of the study: Ten polymorphic chloroplast microsatellite (cpSSR) markers were developed and characterized in an endemic and endangered herb, Maianthemum bicolor (Asparagaceae s.l.), for use in conservation genetics. Methods and Results: Primer sets flanking each of the 10 cpSSR loci in noncoding regions of the chloroplast genome of M. bicolor were designed. These cpSSR markers were tested on a total of 33 adult individuals from three natural populations in South Korea. The number of alleles per locus ranged from two to three. The unbiased haplotype diversity per locus ranged from 0.061 to 0.682. All markers were successfully transferred to the congeneric species M. japonicum, M. bifolium, and M. dilatatum with polymorphisms among the species. Conclusions: The developed cpSSR markers will be useful in assessing the genetic diversity and population structure of M. bicolor and will help to infer its molecular identification, thereby providing a basis for conservation.

The phylogenetic position of the monotypic genus Kontumia (Polypodiaceae) is contentious. It has been suggested that Kontumia is related to Gymnogrammitis dareiformis (Drynarioideae) based on spore ornamentation and blade dissection, or it has been assigned as a member of microsoroid ferns (Microsoroideae) based on the shape of rhizome scales. In the present study, we determined the phylogenetic position of K. heterophylla using four chloroplast DNA regions (rbcL, atpB, rps4 + rps4-trnS intergenic spacer [IGS], and trnL-F IGS). A parsimony consensus tree indicated that K. heterophylla is not related to G. dareiformis, but is nested within the Leptochilus lineage of Microsoroideae. This relationship is also supported by sharing of clathrate scales on the rhizome, which is not found in G. dareiformis. Although marked morphological disparities are found between K. heterophylla and the Leptochilus lineage in terms of leaf dissection, fertile-sterile leaf differentiation, and sori arrangement, our results indicate that these characters have evolved independently several times in Polypodiaceae.