基于核基因c-mos的鸫亚科部分鸟类系统发生关系

采用分子系统学方法对鸫亚科Turdinae 11属21种鸟类的核基因c-mos进行了系统发生分析.所测序列经对位排列后共572个位点,其中核苷酸变异位点111个,简约信息位点71个.以太平鸟Bombycilla garrulus作外群,采用邻接法、最大简约法和最大似然法分别构建其系统发生树.重建的系统发生树显示:所研究鸫亚科21种鸟类分成2个支系,第1个支系包括鸫属Turdus和地鸫属Zoothera.第2个支系包括红尾鸲属Phoenicurus、矶鸫属Monticola、水鸲属Rhyacornis、鸲属Tarsiger、溪鸲属Chainarrornis、石即鸟属Saxicola、燕尾属Enivurus、歌鸲属Luscinia和鹊鸲属Copsychus.红尾鸲属为并系类群,水鸲属和溪鸲属聚到这一支系;歌鸲属与燕尾属互为姐妹群,再与鸲属聚合构成另一支系;宝兴歌鸫Turdus mupinensis独立于鸫属及地鸫属之外,形成单独一个分支.     

A molecular phylogenetic analysis of the "true thrushes" (Aves: Turdinae)

The true thrushes (Passeriformes: Muscicapidae, subfamily Turdinae) are a speciose and widespread avian lineage presumed to be of Old World origin. Phylogenetic relationships within this assemblage were investigated using mitochondrial DNA (mtDNA) sequence data that included the cytochrome b and ND2 genes. Our ingroup sampling included 54 species representing 17 of 20 putative turdine genera. Phylogenetic trees derived via maximum parsimony and maximum likelihood were largely congruent. Most of the Turdine taxa sampled can be placed into one of six well supported clades. Our data indicate a polyphyletic Zoothera which can be divided into at least two (Afro-Asian and Austral-Asian) main clades. The genus Turdus, as presently recognized, is paraphyletic but forms a well supported clade with the addition of three mostly monotypic genera (Platycichla, Nesocichla, and Cichlherminia). We identify an exclusively New World clade that includes a monophyletic Catharus, Hylocichla, Cichlopsis, Entomodestes, Ridgwayia, and Ixoreus. Members of the morphologically and behaviorally distinct genera Sialia, Myadestes, and Neocossyphus unexpectedly form a basal clade. Using multiple outgroup choices, we show that this group is distantly related, but unequivocally the sister group to the remaining Turdines sampled. The Turdinae appear to be a relatively old songbird lineage, originating in the mid to late Miocene. If the Turdinae are indeed Old World in origin, our data indicate a minimum of three separate invasions of the New World.     

Nuclear and mitochondrial sequence data reveal the major lineages of starlings, mynas and related taxa

We investigated the phylogenetic relationships among the major lineages of the avian family Sturnidae and their placement within the Muscicapoidea clade using two nuclear (RAG-1 and myoglobin) and one mitochondrial gene (ND2). Among Muscicapoidea, we recovered three clades corresponding to the families Cinclidae, Muscicapidae and Sturnidae (sensu [Sibley, C.G., Monroe Jr., B.L., 1990. Distribution and Taxonomy of Birds of the World. Yale University Press, New Haven, CT]). Within the sturnoid lineage Mimini and Sturnini are sister groups, with Buphagus basal to them. We identified three major lineages of starlings: the Philippine endemic genus Rhabdornis, an Oriental-Australasian clade (genera Scissirostrum, Gracula, Mino, Ampeliceps, Sarcops, Aplonis), and an Afrotropical-Palaearctic clade (all African taxa, Sturnus and Acridotheres). We discuss the biogeographic implications of our findings and suggest an Asiatic origin for this family. The congruence between the age of major clades, estimated by NPRS, and palaeoclimatic data present evidence for the role of climatic changes in shaping present day distribution of the group.     

基于细胞色素b的鸫亚科部分鸟类的系统进化

采用分子系统学方法对鸫亚科(Turdinae)16属35种鸟类的线粒体细胞色素b基因进行系统发生分析。所测序列经对位排列后共983bp,包含变异位点399个,简约信息位点349个。以太平鸟(Bombycillagarrulus)和雪松太平鸟(Bombycillacedrorum)为外群,采用邻接法、最大简约法、最大似然法和贝叶斯法分别构建鸫亚科的系统发生树。研究结果表明:构建的系统树将所研究鸫亚科鸟类分为2个支系。第1个支系包括鸫属(Turdus)、地鸫属(Zoothera)和宽嘴鸫属(Cochoa);第2个支系包括歌鸲属(Luscinia)、鸲属(Tarsiger)、鹊鸲属(Copsychus)、薮鸲属(Cercotrichas)、红尾鸲属(Phoenicurus)、水鸲属(Rhyacornis)、燕尾属(Enivurus)、啸鸫属(Myiophoneus)、石属(Saxicola)、属(Oenanthe)、溪鸲属(Chaimarrornis)、矶鸫属(Monticola)和欧亚鸲属(Erithacus)。其中地鸫属并非单系类群;红尾鸲属为并系发生,水鸲属和溪鸲属归并到这一支系;石属与矶鸫属互为姐妹群,再与属聚合构成另一支系;然后上述两个支系构成姐妹群;歌鸲属和鸲属聚成姐妹群。对于鹊鸲属、薮鸲属、啸鸫属、欧亚鸲属、宽嘴鸫属和燕尾属,本研究结果并没有完全解决它们在大分支内与其它属间的亲缘关系     

A molecular assessment of phylogenetic relationships and lineage accumulation rates within the family Salamandridae (Amphibia, Caudata)

We examine phylogenetic relationships among salamanders of the family Salamandridae using approximately 2700 bases of new mtDNA sequence data (the tRNALeu, ND1, tRNAIle, tRNAGln, tRNAMet, ND2, tRNATrp, tRNAAla, tRNAAsn, tRNACys, tRNATyr, and COI genes and the origin for light-strand replication) collected from 96 individuals representing 61 of the 66 recognized salamandrid species and outgroups. Phylogenetic analyses using maximum parsimony and Bayesian analysis are performed on the new data alone and combined with previously reported sequences from other parts of the mitochondrial genome. The basal phylogenetic split is a polytomy of lineages ancestral to (1) the Italian newt Salamandrina terdigitata, (2) a strongly supported clade comprising the "true" salamanders (genera Chioglossa, Mertensiella, Lyciasalamandra, and Salamandra), and (3) a strongly supported clade comprising all newts except S. terdigitata. Strongly supported clades within the true salamanders include monophyly of each genus and grouping Chioglossa and Mertensiella as the sister taxon to a clade comprising Lyciasalamandra and Salamandra. Among newts, genera Echinotriton, Pleurodeles, and Tylototriton form a strongly supported clade whose sister taxon comprises the genera Calotriton, Cynops, Euproctus, Neurergus, Notophthalmus, Pachytriton, Paramesotriton, Taricha, and Triturus. Our results strongly support monophyly of all polytypic newt genera except Paramesotriton and Triturus, which appear paraphyletic, and Calotriton, for which only one of the two species is sampled. Other well-supported clades within newts include (1) Asian genera Cynops, Pachytriton, and Paramesotriton, (2) North American genera Notophthalmus and Taricha, (3) the Triturus vulgaris species group, and (4) the Triturus cristatus species group; some additional groupings appear strong in Bayesian but not parsimony analyses. Rates of lineage accumulation through time are evaluated using this nearly comprehensive sampling of salamandrid species-level lineages. Rate of lineage accumulation appears constant throughout salamandrid evolutionary history with no obvious fluctuations associated with origins of morphological or ecological novelties.     

基于13 个内含子的序列探讨鲸目的系统发育关系

本文基于实验室筛选得到的13 对内含子标记,在鲸偶蹄目的15 个物种中进行有效扩增,并重建了这15
个物种的系统发育关系。结果表明,抹香鲸总科(Physeteroidea) 位于齿鲸亚目(Odontoceti)的基部,从而支
持了传统的齿鲸亚目的单系性。在海豚总科(Delphinoidea)内部,贝斯分析结果支持了鼠海豚科(Phocoenidae)
和一角鲸科(Monodontidae)的姐妹群关系,而后再与海豚科(Delphinidae)相聚。系统发育分析同时还
强烈支持了海豚科的四个属(Sousa,Tursiops,Stenella,Delphinus)组成一个单系的“复合体”。另外,我们的分
析结果并不支持瓶鼻海豚属(Tursiops)和原海豚属(Stenella)的单系性。基于松散分子钟的分歧时间估算与以
往文献中的结果没有明显差异。这些研究结果提示,核基因内含子序列有希望解决一些长期存在的鲸类系统发
育问题。     

介形纲丽足目和速足目及相关类群18S rDNA分子系统发育的研究

文中分析现生介形类 (Ostracoda) 4目 2 1科 2 9属的 18SrDNA部分序列 ,采用最大似然法 (ML)、邻接法 (NJ)和最大简约法 (MP) ,尝试构建介形类的分子系统树 ;结合介形类的形态特征和化石记录 ,主要对速足目(Podocopida)、丽足目 (Myodocopida)及其超科级分类阶元的系统发生关系进行探讨。 3种分析方法均支持形态学上Podocopida ,Myodocopida和海萤超科 (Cypridinacea)的界定 ;但对Podocopida目土菱介超科 (Bairdiacea)的系统地位提出质疑 ,该类群可能不是单系发生的自然类群。上述分析显示 ,Podocopida,Myodocopida,Platycopida和Halo cypridina组成一个单系群 ;介形类在目、超科、科和属的水平上可能发生过多次辐射分化     

Phylogenetic relationships of aroids and duckweeds (Araceae) inferred from coding and noncoding plastid DNA

Familial, subfamilial, and tribal monophyly and relationships of aroids and duckweeds were assessed by parsimony and Bayesian phylogenetic analyses of five regions of coding (rbcL, matK) and noncoding plastid DNA (partial trnK intron, trnL intron, trnL-trnF spacer) for exemplars of nearly all aroid and duckweed genera. Our analyses confirm the position of Lemna and its allies (formerly Lemnaceae) within Araceae as the well-supported sister group of all aroids except Gymnostachydoideae and Orontioideae. The last two subfamilies form the sister clade of the rest of the family. Monophyly of subfamilies Orontioideae, Pothoideae, Monsteroideae, and Lasioideae is supported, but Aroideae are paraphyletic if Calla is maintained in its own subfamily (Calloideae). Our results suggest expansion of the recently proposed subfamily Zamioculcadoideae (Zamioculcas, Gonatopus) to include Stylochaeton and identify problems in the current delimitation of tribes Anadendreae, Heteropsideae, and Monstereae (Monsteroideae), Caladieae/Zomicarpeae, and Colocasieae (Aroideae). Canalization of traits of the spathe and spadix considered typical of Araceae evolved after the split of Gymnostachydoideae, Orontioideae, and Lemnoideae. An association with aquatic habitats is a plesiomorphic attribute in Araceae, occurring in the helophytic Orontioideae and free-floating Lemnoideae, but evolving independently in various derived aroid lineages including free-floating Pistia (Aroideae).     

Phylogeny of Myrmeleontiformia based on larval morphology (Neuropterida: Neuroptera)

The suborder Myrmeleontiformia is a derived lineage of lacewings (Insecta: Neuroptera) including the families Psychopsidae, Nemopteridae, Nymphidae, Ascalaphidae and Myrmeleontidae. In particular, Myrmeleontidae (antlions) are the most diverse neuropteran family, representing a conspicuous component of the insect fauna of xeric environments. We present the first detailed quantitative phylogenetic analysis of Myrmeleontiformia, based on 107 larval morphological and behavioural characters for 36 genera whose larvae are known (including at least one representative of all the subfamilies of the suborder). Four related families were used as outgroups to polarize character states. Phylogenetic analyses were conducted using both parsimony and Bayesian methods. The reconstructions resulting from our analyses corroborate the monophyly of Myrmeleontiformia. Within this clade, Psychopsidae are recovered as the sister family to all the remaining taxa. Nemopteridae (including both subfamilies Nemopterinae and Crocinae) are recovered as monophyletic and sister to the clade comprising Nymphidae + (Myrmeleontidae + Ascalaphidae). Nymphidae consist of two well‐supported clades corresponding to the subfamilies Nymphinae and Myiodactylinae. Our results suggest that Ascalaphidae may not be monophyletic, as they collapse into an unresolved polytomy under the Bayesian analysis. In addition, the recovered phylogenetic relationships diverge from the traditional classification scheme for ascalaphids. Myrmeleontidae are reconstructed as monophyletic, with the subfamilies Stilbopteryginae, Palparinae and Myrmeleontinae. We retrieved a strongly supported clade comprising taxa with a fossorial habit of the preimaginal instars, which represents a major antlion radiation, also including the monophyletic pit‐trap building species.     

Diversification and biogeography of the Neotropical caviomorph lineage Octodontoidea (Rodentia: Hystricognathi)

The rodent superfamily Octodontoidea comprises 6 families, 38 genera, and 193 living species of spiny rats, tuco-tucos, degus, hutias, and their relatives. All are endemic to the Neotropical Region where they represent roughly three-quarters of extant caviomorphs. Although caviomorph monophyly is well established and phylogenetic hypotheses exist for several families, understanding of octodontoid relationships is clouded by sparse taxon sampling and single-gene analyses. We examined sequence variation in one mitochondrial (12S rRNA) and three nuclear genes (vWF, GHR, and RAG1) across all caviomorph families (including 47 octodontoid species), all phiomorph families, and the sole remaining hystricognath family, using the gundi (Ctenodactylus) and springhaas (Pedetes) as outgroups. Our analyses support the monophyly of Phiomorpha, Caviomorpha, and the caviomorph superfamilies Cavioidea (Dasyproctidae, Cuniculidae, and Caviidae, the latter including Hydrochoerus), Erethizontoidea, Chinchilloidea (including Dinomyidae), and Octodontoidea. Cavioids and erethizontoids are strongly supported as sisters, whereas chinchilloids appear to be sister to octodontoids. Among octodontoids, Abrocomidae is consistently recovered as the basal element, sister to a pair of strongly supported clades; one includes Octodontidae and Ctenomyidae as reciprocally monophyletic lineages, whereas the other includes taxa currently allocated to Echimyidae, Capromyidae and Myocastoridae. Capromys appears near the base of this clade, in keeping with current classification, but Myocastor is nested securely inside a clade of Echimyidae that also contains eumysopines, echimyines and dactylomyines. Another, more weakly supported clade of Echimyidae contains fossorial and scansorial taxa from the Chaco-Cerrado-Caatinga and the Atlantic Forest. Biogeographic analyses robustly recover the Patagonia-Southern Andes complex as ancestral for the Octodontoidea, with three component lineages emerging by the Oligocene-Miocene boundary (～23Ma): (1) stem abrocomids in the Central and Southern Andes; (2) a lineage leading to octodontids plus ctenomyids in Patagonia, later dispersing into the Chaco-Cerrado-Caatinga; and (3) a lineage leading to echimyids, capromyids, and myocastorids that subsequently radiated in more mesic biomes, including Amazonia, Atlantic Forest, and the Antilles. This reconstruction refutes earlier ideas that the diverse, generalized, mainly lowland family Echimyidae, which appears early in the fossil record, gave rise to the Andean lineages of octodontoids-instead, the reverse derivation appears to be true. We recommend formal synonymy of Myocastoridae with Echimyidae but defer a similar treatment of Capromyidae until additional hutia taxa and sequences can be analyzed.     

单子叶植物高级分类阶元系统演化: matK、rbcL和18S rDNA序列的证据

基于两个叶绿体基因（matK和rbcL）和一个核糖体基因（18S rDNA）的序列分析,对代表了基部被子植物和单子叶植物主要谱系分支的86科126属151种被子植物（单子叶植物58科86属101种）进行了系统演化关系分析。研究结果表明由胡椒目Piperales、樟目Laurales、木兰目Magnoliales和林仙目Canellales构成的真木兰类复合群是单子叶植物的姐妹群。单子叶植物的单系性在3个序列联合分析中得到98％的强烈自展支持。联合分析鉴定出9个单子叶植物主要谱系（广义泽泻目Alismatales、薯蓣目Dioscorcales、露兜树目Pandanales、天门冬目Asparagalcs、百合目Liliales、棕榈目Arecales、禾本目Poales、姜目Zingiberales、鸭跖草目Commelinales）和6个其他被子植物主要谱系（睡莲目Nymphaeales、真双子叶植物、木兰目、樟目、胡椒目、林仙目）。在单子叶植物内,菖蒲目Acorales（菖蒲属Acorus）是单子叶植物最早分化的一个谱系,广义泽泻目（包括天南星科Araceae和岩菖蒲科Toficldiaccae）紧随其后分化出来,二者依次和其余单子叶植物类群构成姐妹群关系。无叶莲科Petrosaviaceac紧随广义的泽泻目之后分化出来,无叶莲科和剩余的单子叶植物类群形成姐妹群关系,并得到了较高的支持率。继无叶莲科之后分化的类群形成两个大的分支：一支是由露兜树目和薯蓣目构成,二者形成姐妹群关系：另一支是由天门冬目、百合目和鸭跖草类复合群组成,三者之间的关系在单个序列分析和联合分析中不稳定,需要进一步扩大取样范围来确定。在鸭跖草类复合群分支内,鸭跖草目和姜目的姐妹群关系在3个序列联合分析和2个序列联合分析的严格一致树中均得到强烈的自展支持,获得的支持率均是100％。但是,对于棕榈目和禾本目在鸭跖草类中的系统位置以及它们和鸭跖草目-姜目之间的关系,有待进一步解决。值得注意的是,无叶莲科与其他单子叶植物类群（除菖蒲目和泽泻目外）的系统关系在本文中获得较高的自展支持率,薯蓣目和天门冬目的单系性在序列联合分析中都得到了较好的自展支持,而这些在以往的研究中通常支持率较低。鉴于菖蒲科和无叶莲科独特的系统演化位置,本文支持将其分别独立成菖蒲目和无叶莲目Petrosavialcs的分类学界定。     

Molecular phylogenetics of squirrelfishes and soldierfishes (Teleostei: Beryciformes: Holocentridae): Reconciling more than 100 years of taxonomic confusion

Squirrelfishes and soldierfishes (Holocentridae) are among the most conspicuous species in the nocturnal reef fish community. However, there is no clear consensus regarding their evolutionary relationships, which is reflected in a complicated taxonomic history. We collected DNA sequence data from multiple single copy nuclear genes and one mitochondrial gene sampled from over fifty percent of the recognized holocentrid species and infer the first species-level phylogeny of the Holocentridae. Our results strongly support the monophyly of the clades Myripristinae (soldierfishes) and Holocentrinae (squirrelfishes). The molecular phylogenies differ with regard to previous hypotheses of relationships within the Myriprisitinae, resolving a clade of cryptic reef associated and deep water non-reef dwelling lineages (Corniger+Plectrypops+Ostichthys) that is the sister lineage to a monophyletic Myripristis. Within Holocentrinae, Neoniphon and Sargocentron are strongly supported as paraphyletic, while Holocentrus is nested within Sargocentron. Using Bayesian ancestral state reconstruction methods, we demonstrate the taxonomically diagnostic characters for Neoniphon and Sargocentron likely represent character states with a complex evolutionary history that is not reflective of shared common ancestry. We propose a new classification for Holocentrinae, recognizing four lineages that are treated as genera: SargocentronFowler, 1904, HolocentrusScopoli, 1777, FlameoJordan and Evermann, 1898, and NeoniphonCastelnau, 1875.     

A new Indo-Malayan member of the Stenostiridae (Aves: Passeriformes) revealed by multilocus sequence data: Biogeographical implications for a morphologically diverse clade of flycatchers

Recent molecular studies on passerine birds have highlighted numerous discrepancies between traditional classification and the phylogenetic relationships recovered from sequence data. Among the traditional families that were shown to be highly polyphyletic are the Muscicapidae Old World flycatcher. This family formerly included all Old World passerines that forage on small insects by performing short sallies from a perch. Genera previously allocated to the Muscicapidae are now thought to belong to at least seven unrelated lineages. While the peculiarity of most of these lineages has been previously recognized by Linnean classification, usually at the rank of families, one, the so-called Stenostiridae, a clade comprising three Afrotropical and Indo-Malayan genera, has only recently been discovered. Here, we address in greater detail the phylogenetic relationships and biogeographic history of the Stenostiridae using a combination of mitochondrial and nuclear data. Our analyses revealed that one species, Rhipidura hypoxantha, previously attributed to the Rhipiduridae (fantails), is in fact a member of the Stenostiridae radiation and sister to the South African endemic genus Stenostira (Fairy Flycatcher). Our dating analyses, performed in a relative-time framework, suggest that the splits between Stenostira/R. hypoxantha and Culicicapa/Elminia occurred synchronously. Given that the Stenostiridae assemblage has been consistently recovered by independent studies, we clarify its taxonomic validity under the rules of the International Code of Zoological Nomenclature.     

The genus Coleodactylus (Sphaerodactylinae, Gekkota) revisited: a molecular phylogenetic perspective

Nucleotide sequence data from a mitochondrial gene (16S) and two nuclear genes (c-mos, RAG-1) were used to evaluate the monophyly of the genus Coleodactylus, to provide the first phylogenetic hypothesis of relationships among its species in a cladistic framework, and to estimate the relative timing of species divergences. Maximum Parsimony, Maximum Likelihood and Bayesian analyses of the combined data sets retrieved Coleodactylus as a monophyletic genus, although weakly supported. Species were recovered as two genetically and morphological distinct clades, with C. amazonicus populations forming the sister taxon to the meridionalis group (C. brachystoma, C. meridionalis, C. natalensis, and C. septentrionalis). Within this group, C. septentrionalis was placed as the sister taxon to a clade comprising the rest of the species, C. meridionalis was recovered as the sister species to C. brachystoma, and C. natalensis was found nested within C. meridionalis. Divergence time estimates based on penalized likelihood and Bayesian dating methods do not support the previous hypothesis based on the Quaternary rain forest fragmentation model proposed to explain the diversification of the genus. The basal cladogenic event between major lineages of Coleodactylus was estimated to have occurred in the late Cretaceous (72.6+/-1.77 Mya), approximately at the same point in time than the other genera of Sphaerodactylinae diverged from each other. Within the meridionalis group, the split between C. septentrionalis and C. brachystoma+C. meridionalis was placed in the Eocene (46.4+/-4.22 Mya), and the divergence between C. brachystoma and C. meridionalis was estimated to have occurred in the Oligocene (29.3+/-4.33 Mya). Most intraspecific cladogenesis occurred through Miocene to Pliocene, and only for two conspecific samples and for C. natalensis could a Quaternary differentiation be assumed (1.9+/-1.3 Mya).     

A modern approach to rotiferan phylogeny: combining morphological and molecular data

The phylogeny of selected members of the phylum Rotifera is examined based on analyses under parsimony direct optimization and Bayesian inference of phylogeny. Species of the higher metazoan lineages Acanthocephala, Micrognathozoa, Cycliophora, and potential outgroups are included to test rotiferan monophyly. The data include 74 morphological characters combined with DNA sequence data from four molecular loci, including the nuclear 18S rRNA, 28S rRNA, histone H3, and the mitochondrial cytochrome c oxidase subunit I. The combined molecular and total evidence analyses support the inclusion of Acanthocephala as a rotiferan ingroup, but do not support the inclusion of Micrognathozoa and Cycliophora. Within Rotifera, the monophyletic Monogononta is sister group to a clade consisting of Acanthocephala, Seisonidea, and Bdelloidea-for which we propose the name Hemirotifera. We also formally propose the inclusion of Acanthocephala within Rotifera, but maintaining the name Rotifera for the new expanded phylum. Within Monogononta, Gnesiotrocha and Ploima are also supported by the data. The relationships within Ploima remain unstable to parameter variation or to the method of phylogeny reconstruction and poorly supported, and the analyses showed that monophyly was questionable for the families Dicranophoridae, Notommatidae, and Brachionidae, and for the genus Proales. Otherwise, monophyly was generally supported for the represented ploimid families and genera.     

基于叶绿体基因组探讨桃金娘目及其近缘类群的系统发育关系

该研究基于叶绿体基因组数据,对桃金娘目(6科44属97种)及其近缘类群(牻牛儿苗目2科5属25种)的系统发育关系进行了分析.结果表明:(1)桃金娘目基因组大小为152～171 kb,包括的蛋白质编码基因数目为74～90个;牻牛儿苗目基因组大小为116～242 kb,包括的蛋白质编码基因数目为75～132个.(2)对比叶...     

Systematics of Amaryllidaceae based on cladistic analysis of plastid sequence data

Cladistic analyses of plastid DNA sequences rbcL and trnL-F are presented separately and combined for 48 genera of Amaryllidaceae and 29 genera of related asparagalean families. The combined analysis is the most highly resolved of the three and provides good support for the monophyly of Amaryllidaceae and indicates Agapanthaceae as its sister family. Alliaceae are in turn sister to the Amaryllidaceae/Agapanthaceae clade. The origins of the family appear to be western Gondwanaland (Africa), and infrafamilial relationships are resolved along biogeographic lines. Tribe Amaryllideae, primarily South African, is sister to the rest of Amaryllidaceae; this tribe is supported by numerous morphological synapomorphies as well. The remaining two African tribes of the family, Haemantheae and Cyrtantheae, are well supported, but their position relative to the Australasian Calostemmateae and a large clade comprising the Eurasian and American genera, is not yet clear. The Eurasian and American elements of the family are each monophyletic sister clades. Internal resolution of the Eurasian clade only partially supports currently accepted tribal concepts, and few conclusions can be drawn on the relationships of the genera based on these data. A monophyletic Lycorideae (Central and East Asian) is weakly supported. Galanthus and Leucojum (Galantheae pro parte) are supported as sister genera by the bootstrap. The American clade shows a higher degree of internal resolution. Hippeastreae (minus Griffinia and Worsleya) are well supported, and Zephyranthinae are resolved as a distinct subtribe. An Andean clade marked by a chromosome number of 2n = 46 (and derivatives thereof) is resolved with weak support. The plastid DNA phylogenies are discussed in the context of biogeography and character evolution in the family.     

Evolution of South American spiny rats (Rodentia,Echimyidae): the star-phylogeny hypothesis revisited

We analyzed the phylogenetic relationships of echimyid genera based on sequences of the cytochrome b, 12S, and 16S mitochondrial genes. Our results corroborate the monophyly of Octodontoidea and the rapid diversification of echimyid rodents as previously proposed. The analyses indicate that the family Echimyidae, including Myocastor to the exclusion of Capromys, is paraphyletic, since Capromys and Myocastor are well-supported sister-taxa. We therefore suggest the inclusion of both Capromys and Myocastor in the family Echimyidae. Five other suprageneric clades are well supported: Dactylomys+Kannabateomys, Euryzygomatomys+Clyomys, Proechimys+Hoplomys, Mesomys+Lonchothrix, and Makalata+(Echimys+Phyllomys). Trinomys and Thrichomys have no clear close relatives, and Isothrix emerged as sister to Mesomys+Lonchothrix, but with no support. We suggest that most of the cladogenesis leading to the extant echimyid genera probably occurred during the Late Miocene, about eight million years ago.