Abietane diterpenoids and other constituents from Clerodendrum trichotomum

The genus Clerodendrum Linn., originally belonging to Verbenaceae, was assigned to Lamiaceae by APG (Angiosperm Phylogeny Group) Ⅱ. Seven abietane diterpenoids (1–7) along with three anthraquinones (8–10) and one neolignan (11) were isolated and identified from the stems of Clerodendrum trichotomum Thunb.. Among them, compounds 4, 6 and 8–11 were reported from the genus Clerodendrum Linn. for the first time. Compounds 1, 3 and 7 were obtained from this species for the first time. Isolation of abietane diterpenoids from C. trichotomum could further comfirm that the genus Clerodendrum belongs to Lamiaceae rather than Verbenaceae.     

臭牡丹中一个新的过氧化物

从四川眉山地区产的臭牡丹（Ｃｌｅｒｏｄｅｎｄｒｕｍ ｂｕｎｇｅｉ Ｓｔｅｕｄ．）地上部分分离到一个新的过氧化物,命名为ｂｕｎｇｅｉｎＡ。其结构通过各项波谱分析得到鉴定,这是首次从马莰草得桐属植物中分到的过氧化物。     

Norigondolella n. gen., eine neue obertriassische Conodontengattung

The development of the genus concept for platform-bearing gondolellid conodonts is discussed. The collective genusNeogondolella Bender & Stoppel s. l. must be subdivided into several genera separated mostly by morphological differences of their platform elements. Only for these genera, but not forNeogondolella s. l., differential diagnoses againstGondolella Stauffer & Plummer s. l. can be given.Norigondolella n. gen., species of which were formerly placed intoParagondolella Mosher s. l.,Gondolella Stauffer & Plummer s. l. orNeogondolella Bender & Stoppel s. l., is a typical gondolellid platform conodont genus of topmost Triassic (Norian-Rhaetian) pelagic sediments. It has evolved from Carnian representatives ofParagondolella, but the lower surface of the platform element shows considerable similarities (homoeomorphy) to the Middle Carboniferous to Middle Permian genusMesogondolella Kozur.     

Infrageneric phylogeny of the genus Gentiana (Gentianaceae) inferred from nucleotide sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA

The internal transcribed spacers (ITSs) of nuclear ribosomal DNA have been sequenced for 20 species of Gentiana. By incorporating previously released sequence data of eight species, phylogenelic analyses using Fitch parsimony and character-state weighted parsimony were carried out. The length of ITS 1 in the taxa surveyed ranged from 223 to 238 bp and ITS2 from 216 to 234 bp. Sequence divergence between pairs of species ranged from 5.0% to 48.9% in ITS1, from 1.1% to 45.3% in ITS2, and from 3.2% to 46.1% in combined data of ITS1 and ITS2. The ITS phylogeny was generally congruent with morphological classifications except that G. asclepiadea was revealed to be closely related to section Gentiana instead of section Pneumonanthe and section Stenogyne was shown to be a paraphyletic group of the genus Gentiana that would be better excluded from the genus. A divergence among the three European endemic sections and the remaining sections of the genus other than section Stenogyne was revealed. Thus the European species of the genus together do not form a monophyletic group. A close relationship between the sections Chondrophyllae s. l. (including section Dolichocarpa), Cruciata and Pneumonanthe was suggested. The section Frigidae s. l. (including sections Monopodiae, Isomeria, Microsperma, and Phyllocalyx) contained two well-supported clades: section Frigidae s. str. and all others together. The monophyly of the typically dysploid group section Chondrophyllae s. l. was confirmed. Optimization of chromosome numbers on the ITS phylogeny suggested that 2/1 = 26 is a plesiomorphic state for the clade comprising sections Frigidae s. l., Cruciata, Pneumonanthe, and Chondrophyllae s. l., and probably 2n = 20 is a plesiomorphic state for the dysploid group, section Chondrophyllae s. l.     

Molecular systematics of the neotropical shovelnose catfish genus Pseudoplatystoma Bleeker 1862 based on nuclear and mtDNA markers

Pseudoplatystoma is a commercially important genus of Neotropical migratory catfishes widely distributed in all major river basins of South America. Historically, only three species were recognized, but a recent revision proposed eight putative morphospecies for the genus. A molecular study based on mitochondria DNA (mtDNA) provided support for recognition of only some of the species and raised questions about species boundaries in this group. We present a more encompassing analysis based on mtDNA (cytochrome b, 818bp) and nuclear DNA-based phylogenies (Rag1 intron 1, 664bp and S7 intron 1, 635bp) for a more extensive sampling (279 individuals from 42 localities) of all putative species in all major river basins. Patterns generated by individual gene genealogies and a multispecies coalescent analysis provided evidence to suggest recognition of only four distinct species in this genus: Pseudoplatystoma magdaleniatum, Pseudoplatystoma corruscans, Pseudoplatystoma tigrimun (sensu lato) and Pseudoplatystoma fasciatum (sensu lato). The species phylogeny places P. magdaleniatum as the sister group to all the other species in the genus, but the relationships among P. fasciatum s.l, P. tigrimum s.l., and P. corruscans could not be resolved with confidence.     

Molecular phylogenetics reveals Leontodon (Asteraceae, Lactuceae) to be diphyletic

The plastid matK gene, trnL/F spacer, and nuclear rDNA ITS were sequenced for 36 species of Leontodon and 29 taxa of related genera of tribe Lactuceae. Phylogenetic relationships inferred from the independent and combined data are largely congruent and reveal that Leontodon sensu lato (s.l.) as presently defined is diphyletic: L. subgenus Leontodon forms a clade with Helminthotheca, Picris and Hypochaeris as sister genera, whereas L. subgenus Oporinia appears as a separate clade with strong bootstrap support and is thus better treated as a separate genus. Previous sectional classifications of Leontodon s.l. are considered in the light of DNA and additional morphological and karyological data. Support is presented for a core group of Hypochaeridinae sensu stricto (s.s.) with the two clades of Leontodon s.l., Helminthotheca, Picris, and Hypochaeris, whereas Urospermum, Hyoseris, Aposeris, and Rhagadiolus appear to be positioned more distantly.     

Phylogeny of the bee genus Halictus (Hymenoptera: halictidae) based on parsimony and likelihood analyses of nuclear EF-1alpha sequence data

We investigated higher-level phylogenetic relationships within the genus Halictus based on parsimony and maximum likelihood (ML) analysis of elongation factor-1alpha DNA sequence data. Our data set includes 41 OTUs representing 35 species of halictine bees from a diverse sample of outgroup genera and from the three widely recognized subgenera of Halictus (Halictus s.s., Seladonia, and Vestitohalictus). We analyzed 1513 total aligned nucleotide sites spanning three exons and two introns. Equal-weights parsimony analysis of the overall data set yielded 144 equally parsimonious trees. Major conclusions supported in this analysis (and in all subsequent analyses) included the following: (1) Thrincohalictus is the sister group to Halictus s.l., (2) Halictus s.l. is monophyletic, (3) Vestitohalictus renders Seladonia paraphyletic but together Seladonia + Vestitohalictus is monophyletic, (4) Michener's Groups 1 and 3 are monophyletic, and (5) Michener's Group 1 renders Group 2 paraphyletic. In order to resolve basal relationships within Halictus we applied various weighting schemes under parsimony (successive approximations character weighting and implied weights) and employed ML under 17 models of sequence evolution. Weighted parsimony yielded conflicting results but, in general, supported the hypothesis that Seladonia + Vestitohalictus is sister to Michener's Group 3 and renders Halictus s.s. paraphyletic. ML analyses using the GTR model with site-specific rates supported an alternative hypothesis: Seladonia + Vestitohalictus is sister to Halictus s.s. We mapped social behavior onto trees obtained under ML and parsimony in order to reconstruct the likely historical pattern of social evolution. Our results are unambiguous: the ancestral state for the genus Halictus is eusociality. Reversal to solitary behavior has occurred at least four times among the species included in our analysis.     

A phenetic study of Cassia sensu lato (Leguminosae-Caesalpinioideae: Cassieae: Cassiinae) in Thailand

Cassia L. sensu lato, a large heterogeneous genus of flowering plants, occurs naturally in the tropics around the world. Recent works based on floral morphology have supported a division of this genus into three genera, namely Cassia L. s. str., Chamaecrista Moench and Senna Mill. In order to investigate this new classification, 508 specimens of 18 taxa of the genus Cassia s.l. grown in Thailand were analyzed using cluster analysis and canonical discriminant analysis. The total 32 vegetative and reproductive morphological characters were employed in these analyses. In cluster analysis, Cassia s.l. can be separated into four groups, respectively viz. Chamaecrista, Senna alata, Senna and Cassia s /str. The four-cluster grouping is discussed. From a canonical discriminant analysis using the four-cluster grouping as a priori groups, it can be concluded that Cassia s. str., Senna, and Chamaecrista are indeed distinct taxa. The three most important characters that separate the three genera are filament length, fruit length, and ovary stalk length. These quantitative characters, together with some qualitative characters, were useful in constructing an identification key to these genera. Among the three genera, it was also found that Senna is rather a heterogeneous taxon. The difference between the studied species was discussed.     

Phylogeny and taxonomy of Afrocayratia,a new genus of Vitaceae from continental Africa and Madagascar

The genus Cayratia Juss. in the traditional sense (i.e., Cayratia s.l.) of the grape family has been shown to be non‐monophyletic. Previous studies supported the splitting of Cayratia s.l. into three genera, that is, Cayratia s.s., Causonis Raf., and a new genus representing the African Cayratia clade. However, the morphology of the African Cayratia clade has not been studied carefully and its phylogenetic position within Vitaceae remains unclear. Our study integrates molecular, distributional, and morphological data and supports the recognition of the new genus Afrocayratia from continental Africa and Madagascar. Phylogenetic analyses strongly support the monophyly of Afrocayratia and resolve it as a sister of Cayratia s.s. based on the chloroplast data, but it is placed sister to Cyphostemma based on the internal transcribed spacer dataset. Molecular dating suggests that Afrocayratia split with Cayratia s.s. during the Paleocene, but that the extant species of Afrocayratia did not diversify until the early Miocene. Afrocayratia differs from its allied genera in having short stigmas and seeds with subcircular ventral infold cavities in cross‐section. Three clades are detected within Afrocayratia, with A. debilis (Baker) J.Wen & L.M.Lu as the first diverged lineage. The second diverged lineage includes A. delicatula (Willems) J.Wen & Z.D.Chen and A. gracilis (Guill. & Perr.) J.Wen & Z.D.Chen. The third diverged lineage includes A. imerinensis (Baker) J.Wen & L.M.Lu, A. longiflora (Desc.) J.Wen & Rabarijaona, and A. triternata (Baker) J.Wen & Rabarijaona from Madagascar, which form a monophyletic group that diverged from the second lineage in the middle Miocene. Combining the morphological and molecular evidence, we formally describe the new genus Afrocayratia, make seven new combinations, and provide a key to species of the genus.     

Phylogenomic conflict analyses in the apple genus Malus s.l. reveal widespread hybridization and allopolyploidy driving diversification,with insights into the complex biogeographic history in the Northern Hemisphere

Phylogenomic evidence from an increasing number of studies has demonstrated that different data sets and analytical approaches often reconstruct strongly supported but conflicting relationships. In this study, 785 single-copy nuclear genes and 75 complete plastomes were used to infer the phylogenetic relationships and estimate the historical biogeography of the apple genus Malus sensu lato, an economically important lineage disjunctly distributed in the Northern Hemisphere and involved in known and suspected hybridization and allopolyploidy events. The nuclear phylogeny recovered the monophyly of Malus s.l. (including Docynia); however, the genus was supported to be biphyletic in the plastid phylogeny. An ancient chloroplast capture event in the Eocene in western North America best explains the cytonuclear discordance. Our conflict analysis demonstrated that ILS, hybridization, and allopolyploidy could explain the widespread nuclear gene tree discordance. One deep hybridization event (Malus doumeri) and one recent event (Malus coronaria) were detected in Malus s.l. Furthermore, our historical biogeographic analysis integrating living and fossil data supported a widespread East Asian-western North American origin of Malus s.l. in the Eocene, followed by several extinction and dispersal events in the Northern Hemisphere. We also propose a general workflow for assessing phylogenomic discordance and biogeographic analysis using deep genome skimming data sets.     

Chromosome numbers and mode of reproduction in Picrishieracioides s.l. (Asteraceae), with notes on some other Picristaxa

Chromosome numbers for 88 plants of Picris hieracioides s.l. originating from 32 localities from Austria, Andorra, Croatia, France, Germany, Hungary, Italy, Slovakia and Spain are reported. All analysed plants were diploid, with 2n=2x=10. In addition to P. hieracioides s.l., we also found diploidy (2n=2x=10) in P. nuristanica from Kirgizia and P. japonica from Japan. Our data confirmed previously published results in the literature. We also studied the mode of reproduction in all three taxa. Picris nuristanica and P. japonica s.l. were able to produce some seeds by selfing, and this is the first record of autogamy in this genus. In P. hieracioides s.l. only strict allogamy was found, demonstrating the presence of a self-incompatibility system in this species. Because apomixis, namely apospory, has previously been reported in P. hieracioides , castration experiments were performed in order to confirm or reject this report. However, no evidence of apomictic seed formation was found within this species. In the light of our results, P. hieracioides should be considered a strictly sexual taxon.     

Molecular systematics of the fern genus Hymenophyllum s.l. (Hymenophyllaceae) based on chloroplastic coding and noncoding regions

We investigated the phylogenetic relationships of the filmy fern genus Hymenophyllum s.l. using the rbcL and rps4 genes and the intergenic spacer rps4-trnS. Because of variation in length of the noncoding marker, we tested and compared three methods for integrating indels. They proved to be useful for estimating a phylogeny of the genus. The rps4-trnS marker, with coded indels integrated, produced better resolution than analysis of either rps4 or rbcL, and combining the three data sets allowed us to obtain a well resolved and strongly supported topology. We interpret our data as showing support for the classical bigeneric system for the family, and call into question several classifications proposed in the past century. The segregate genera Cardiomanes, Hymenoglossum, Serpyllopsis, and Rosenstockia are embedded within Hymenophyllum s.l. Although the deepest relationships within the genus remain uncertain, two subgenera described by Morton do have some support: (1) Sphaerocionium, in which the problematic section Microtrichomanes is embedded; and (2) a diverse Hymenophyllum, including species that were placed originally in Serpyllopsis, Rosenstockia, Hemicyatheon, and Craspedophyllum by Copeland. Subgenus Mecodium appears to be polyphyletic; nevertheless, a subgroup within Mecodium is strongly supported. Several unexpected associations gain support from cytological data and certain morphological characters not previously used to distinguish species groups within Hymenophyllum s.l.     

Phylogenetic analysis of the Silurian Retiolitidae

A cladistic, phylogenetic analysis of the Retiolitidae, using 18 genera and parataxa and 23 characters, reveals that two distinct clades can be recognized within this family, as well as a primitive stem-group that includes the genus Pseudoretiolites . One of the derived clades includes Pseudo-plegmatograptus, Stomatograptus and Retiolites , which are assigned to the revised subfamily Retiolitinae. The other derived clade, the early part of which shows a paraphyletic relationship, includes the remaining known genera Rotaretiofites s.l., Paraplectograptus s.l., Sokolovograptus, Plectograptus, Agastograptus, Spinograptus, Gothograptus, Eisenackograptus, Neogothograptus, Semiplectograptus, Plectodinemagraptus and Holoretiolites . These genera are all included within an expanded Plectograptinae. The biostratigraphic distribution of these taxa suggests that these two clades diverged from a Pseudoretiolites-like ancestor in mid-Aeronian time.     

Ticks (Ixodida) on humans from central Panama, Panama (2010–2011)

From January 2010 to December 2011, a total of 138 cases of ticks feeding on humans were reported from 11 locations in central Panama. Five of these locations were situated in forest environments, three in rural landscapes and three in urban areas. The ticks were submitted to the Gorgas Memorial Institute, where nine species were identified among 65 specimens: Amblyomma cajennense s.l., A. dissimile, A. naponense, A. oblongoguttatum, A. ovale, A. sabanerae, A. tapirellum, Haemaphysalis juxtakochi and Rhipicephalus sanguineus s.l. The remaining 73 specimens consisted of unidentified immature ticks, all belonging to the genus of Amblyomma. Rhipicephalus sanguineus s.l. was the species most frequently associated with humans, particularly in urban environments. In rural landscapes, tick bites were most often caused by A. cajennense s.l., whereas A. tapirellum was the species most often found parasitizing humans in forest environments. These data provide information on the tick species most commonly associated with humans in forested environments, rural areas and cities around the Panama Canal.     

Phylogenetic relationships and evolutionary history of the shrimp genus Penaeus s.l. derived from mitochondrial DNA

Mitochondrial DNA sequences were used to reconstruct the phylogeny of the Penaeus s.l. genus of marine shrimp. This phylogeny was used to test the validity of hypotheses on the species groupings, in particular the subgenus/genus subdivision, and on the species' evolutionary history. Newly derived sequences of both 16S rRNA and COI genes from 19 species of Penaeus s.l. and one outgroup were combined with previous sequences from seven additional species to allow analysis of 26 of the 28 recognised (or nominated) species. Phylogenetic analyses do not support the validity of all the previously created six subgenera (or genera) but provide evidence for division of the genus into two previously unrecognised clades (Melicertus+Marsupenaeus and Penaeus s.s.+Fenneropenaeus+Farfantepenaeus+Litopenaeus). A key conclusion from a previous molecular study, that the subgenera Farfantepenaeus and Litopenaeus are paraphyletic, was rejected. The molecular data support an Indo-West Pacific origin of the genus, with a single relatively recent colonisation of the Western Hemisphere, and subsequent subdivision into two clades prior to the emergence of the Panamanian isthmus.     

Further insights into the phylogeny of Arabidopsis (Brassicaceae) from nuclear Atmyb2 flanking sequence

Arabidopsis thaliana is the preeminent plant model organism. However, significant advances in evolution and ecology are being made by expanding the scope of research beyond this single species into the broader genus Arabidopsis. Surprisingly, few studies have rigorously investigated phylogenetic relationships between the nine Arabidopsis species, and this study evaluates both these and hypotheses related to two instances of intra-generic hybridization. DNA sequences from the 5' flanking region of the nuclear Atmyb2 gene from 12 of the 14 Arabidopsis taxa were used to reconstruct the generic phylogeny. The strict consensus tree was highly concordant with previous studies, identifying lineages corresponding to widespread species but exhibiting a large basal polytomy. Our data indicates that the paternal parent of the allopolyploid A. suecica is A. neglecta rather than A. arenosa s.l., although the need for a detailed phylogeographical study of these three species is noted. Finally, our data provided additional phylogenetic evidence of hybridization between Arabidopsis lyrata s.l. and A. halleri s.l. Taken together, the well-defined lineages within the genus and the potential for hybridization between them highlight Arabidopsis as a promising group for comparative and experimental studies of hybridization.     

Phylogenetic relationships of Thlaspi s.l. (subtribe Thlaspidinae, Lepidieae) and allied genera based on chloroplast DNA restriction-site variation

Chloroplast DNA restriction-site variation was analyzed in 30 accessions representing 20 species from the major lineages in Thlaspi s.l. (previously described as genera by Meyer 1973, 1979) and allied genera from the subtribe Thlaspidinae (Peltaria, Teesdalia, Cochlearia, Ionopsidium, Aethionema). A total of 161 variable restriction sites were detected. Phylogenetic analyses indicated a division of Thlaspi s.l. into three groups consistent with Meyer's genera Thlaspi s. str., Microthlaspi and Noccaea/Raparia. The genus Thlaspi s.l. as currently described proved to be paraphyletic because one of its major lineages, i.e. Thlaspi s. str., appeared to be more closely related to other genera (Peltaria, Teesdalia) than to the remaining lineages of Thlaspi s.l., i.e. Noccaea/Raparia and Microthlaspi. Sequence divergence values (100 x p) between the Thlaspi s.l. lineages were similar to values between these groups and related genera (Teesdalia, Peltaria), respectively. Chloroplast DNA variation was also used to assess subtribal classification of the genera studied. The cpDNA data were inconsistent with the controversial taxonomic classifications based on morphology. The molecular data would suggest that (1) the subtribe Thlaspidinae, as traditionally described, is not monophyletic; (2) the Thlaspidinae should be reduced to a group consisting of Thlaspi s. str., Peltaria, Teesdalia, Microthlaspi, Noccaea/Raparia, and that Aethionema should be excluded from the Thlaspidinae; and (3) Cochlearia and Ionopsidium represent the subtribe Cochleariinae.     

Chloroplast DNA variations in sect. Cyclachaena of Iva (Asteraceae)

Much argument has been occasioned by questions having to do with generic concepts in the tribe Heliantheae, subtribe Ambrosiinae, especially involving the genus Iva. Some workers recognize five genera (e.g., Leuciva, Chorisiva, Oxytenia, Cyclachaena, and Iva s. str.), while others recognize only a single genus Iva s. 1. Although chemical, pollen ultrastructure, and other morphological data have challenged the latter concept, relationships among the segregate taxa are still unclear. The current study used cladistic analyses of chloroplast DNA variation to investigate evolutionary relationships within Iva s. l., especially within the controversial section Cyclachaena. Nuclear rDNA was also utilized to test for hybrid origin of selected taxa. The results support the dismemberment of Iva s. l. and recognition of Iva s. str., largely because Iva s. l. is shown to be paraphyletic. Most members of the section Cyclachaena were found to have relatively close interspecific relationships. Nevertheless, cpDNA data strongly support two lineages within Cyclachaena. One lineage, including I. xanthifolia, I. acerosa, I. nevadensis, and I. dealbata, has a close relationship with the genus Euphrosyne. The second lineage includes only one species, I. ambrosiaefolia, which is closely related to Dicoria. The origin of I. ambrosiaefolia was shown to be monophyletic, not involving hybridization.     

The embryology of <Emphasis Type="Italic">Xanthoceras</Emphasis> and its phylogenetic implications

Recent molecular analyses found the Chinese monotypic genus Xanthoceras to be either a sister genus to the rest of a broadly defined Sapindaceae sensu lato (s.l.) including Aceraceae and Hippocastanaceae or the only genus of the Xanthoceraceae. Here we investigate for the first time the embryology of Xanthoceras and compare the embryological data with related taxa to aid in understanding the phylogenetic relationships of this genus. The results indicate that Xanthoceras shares many embryological features with Sapindaceae sensu stricto (s.s.), Aceraceae, and Hippocastanaceae, including a glandular tapetum, simultaneous microsporogenesis, three-colporate pollen grains, a bitegmic and crassinucellate ovule, Polygonum type of embryo sac development, endosperm formation of the nuclear type, and exalbuminous mature seeds. The wide range of similarities in embryological features suggests that Xanthoceras is closely related to other members of Sapindaceae s.l. However, Xanthoceras differs from other Sapindaceae in several morphological characteristics, for instance, five to eight ovules in each locule in Xanthoceras versus one to two ovules in each locule in other Sapindaceae s.l., and five golden horn-like appendages present on both staminate and hermaphrodite flowers of Xanthoceras versus absent on the flowers of other Sapindaceae s.l. We propose that Xanthoceras merits recognition at the subfamily level as Xanthoceroideae, rather than at the family level as Xanthoceraceae. The present study also reveals that late-acting ovarian self-incompatibility (OSI) occurs in X. sorbifolium and that postzygotic OSI contributes to the self-sterility of the species.