Phylogeny of Malpighiaceae: evidence from chloroplast ndhF and trnl-F nucleotide sequences

The Malpighiaceae are a family of ～1250 species of predominantly New World tropical flowering plants. Infrafamilial classification has long been based on fruit characters. Phylogenetic analyses of chloroplast DNA nucleotide sequences were analyzed to help resolve the phylogeny of Malpighiaceae. A total of 79 species, representing 58 of the 65 currently recognized genera, were studied. The 3' region of the gene ndhF was sequenced for 77 species and the noncoding intergenic spacer region trnL-F was sequenced for 65 species; both sequences were obtained for the outgroup, Humiria (Humiriaceae). Phylogenetic relationships inferred from these data sets are largely congruent with one another and with results from combined analyses. The family is divided into two major clades, recognized here as the subfamilies Byrsonimoideae (New World only) and Malpighioideae (New World and Old World). Niedenzu's tribes are all polyphyletic, suggesting extensive convergence on similar fruit types; only de Jussieu's tribe Gaudichaudieae and Anderson's tribes Acmanthereae and Galphimieae are monophyletic. Fleshy fruits evolved three times in the family and bristly fruits at least three times. Among the wing-fruited vines, which constitute more than half the diversity in the family, genera with dorsal-winged samaras are fairly well resolved, while the resolution of taxa with lateral-winged samaras is poor. The trees suggest a shift from radially symmetrical pollen arrangement to globally symmetrical pollen at the base of one of the clades within the Malpighioideae. The Old World taxa fall into at least six and as many as nine clades.     

A complete generic phylogeny of Malpighiaceae inferred from nucleotide sequence data and morphology

? Premise of the study: The Malpighiaceae include ～1300 tropical flowering plant species in which generic definitions and intergeneric relationships have long been problematic. The goals of our study were to resolve relationships among the 11 generic segregates from the New World genus Mascagnia, test the monophyly of the largest remaining Malpighiaceae genera, and clarify the placement of Old World Malpighiaceae. ? Methods: We combined DNA sequence data for four genes (plastid ndhF, matK, and rbcL and nuclear PHYC) from 338 ingroup accessions that represented all 77 currently recognized genera with morphological data from 144 ingroup species to produce a complete generic phylogeny of the family. ? Key results and conclusions: The genera are distributed among 14 mostly well-supported clades. The interrelationships of these major subclades have strong support, except for the clade comprising the wing-fruited genera (i.e., the malpighioid+Amorimia, Ectopopterys, hiraeoid, stigmaphylloid, and tetrapteroid clades). These results resolve numerous systematic problems, while others have emerged and constitute opportunities for future study. Malpighiaceae migrated from the New to Old World nine times, with two of those migrants being very recent arrivals from the New World. The seven other Old World clades dispersed much earlier, likely during the Tertiary. Comparison of floral morphology in Old World Malpighiaceae with their closest New World relatives suggests that morphological stasis in the New World likely results from selection by neotropical oil-bee pollinators and that the morphological diversity found in Old World flowers has evolved following their release from selection by those bees.     

基于28S rRNA基因D2序列的优茧蜂亚科分子系统发育（膜翅目：茧蜂科）

The D2 variable region of 28S ribosomal RNA was sequenced from ethanol specimens or obtained from the literature to provide the first phylogenetie reconstruction of the subfamily Euphorinae (Hymenoptera;Braconidae). Phylogenetic relationships were established by comparing the results using two different methods (distance-based neighbor-joining, NJ; and maximum parsimony, MP) and three different outgroups. The monophyly of the Euphorinae is well supported by all trees generated from molecular data. All phylogenetic reconstructions yielded trees with very similar topologies that only partially resolved the morphologically defined tribes and the relationships within the subfamily. We found no evidence for the monophyletic natures of the tribes Euphorinl, Dinocampini,Perilitini, Syntretini, Comsophorini and Centisitini, but we did find some evidence for the tribes Meteorini and Microctonini. The monophyletic nature of the tribe Meteodnl was well-supported in all trees. We also found the clade containing the LecythodeUa,Microctonus, Orionis and Streblocera to be a monophyletic group, which corresponded to the tribe Microtonini, with Orionis transferred from the tribe Eupholini into Microtonini.Among the genera of Euphorini our results showed strong support for a paraphyletic nature of this group, which can be roughly divided into two clades, one consisting of Aridelus Wesmaelia, the other of Leiophron Peristenus, suggesting both of which may be given tribal rank. The placement of the genus Chrysopophorus is largely uncertain. Two clades,Dinocampus Perilitus and Cosmophorus Rhopalophorus, were constantly resolved in our analyses, with 42-96 and 97-100 bootstrap value support, respectively, suggesting that both of them form monophyletic groups. For members of the Centistini, Pygostolus may be removed and included in Microctonini or other relative tribe.     

Phylogenetic Analyses of Aurantioideae (Rutaceae) Based on Non-Coding Plastid DNA Sequences and Phytochemical Features

Abstract: Sequences of the plastid DNA atp B/ rbc L intergenic spacer and rps16 intron from 23 genera and 47 species of Rutaceae were used to resolve phylogenetic relationships in subfamily Aurantioideae. According to these, the subfamily is monophyletic, but its classical subdivision into tribes Clauseneae and Citreae is only justified if the genus Murraya s.s. (exclusive of the species segregated as Bergera , e.g., Murraya koenigii and M. siamensis ) and Merrillia are transferred to Citreae s.l. This conclusion is also well supported by phytochemistry, demonstrating accumulation of carbazoles in Bergera and Clausena , and of 8-prenylated coumarins and polyoxygenated flavonoids in Murraya s.s. and Merrillia. Formation of both carbazoles, as well as 8-prenylated coumarins, and polyoxygenated flavonoids in Micromelum suggests relationships between Clauseneae s.s. and Citreae s.l. The monophyly of several larger genera in both tribes is supported by relatively high bootstrap percentages and specific chemical profiles for e.g., Clausena, Micromelum, Glycosmis and Atalantia. In contrast, molecular, chemical, and other data show that none of the subtribes recognized within Aurantioideae reflect phylogenetic relationships. Only the clades with Clausena + Bergera, Murraya s.s. + Merrillia, and Citrus + Clymenia + Eremocitrus + Fortunella + Poncirus ("true Citrus fruit trees") are well supported by such data. Among the outgroup genera, Zanthoxylum (Rutoideae) and Toddalia (Toddalioideae) are much closer to each other than to Ruta (Rutoideae).     

Resolving robust phylogenetic relationships of core Brassicaceae using genome skimming data

The Brassicaceae is an economically and scientifically important family distributed globally, including oilseed rape and the model plant, Arabidopsis thaliana. Although growing molecular data have been used in phylogenetic studies, the relationships among major clades and tribes of Brassicaceae are still controversial. Here, we investigated the core Brassicaceae phylogenetics using 222 plastomes and 235 nrDNA cistrons, including 106 plastomes and 112 nrDNA cistrons assembled from newly sequenced genome skimming data of 112 taxa. The sampling covered 73 genera from 61.5% tribes and four unassigned genera and species. Three well supported lineages LI, LII, and LIII were revealed in our plastomic analyses, with LI sister to LII + LIII. In addition, the monophyly of the newly delimitated LII was strongly supported by three different partition strategies, concatenated methods under Bayesian and Maximum Likelihood analyses. LII comprised 13 tribes, including four tribes previously unassigned to any lineage, that is Biscutelleae as the earliest diverging clade and Cochlearieae as the sister to Megacarpaeeae + Anastaticeae. Within LII, the intertribal relationships were also well resolved, except that a conflicting position of Orychophragmus was detected among different datasets. In LIII, Shehbazia was resolved as a member of Chorisproreae, but Chorisproreae, Dontostemoneae, and Euclidieae were all resolved as paraphyletic, which was also confirmed by nrDNA analyses. Moreover, the loss of the rps16 gene was detected as likely to be a synapomorphy of the tribes Arabideae and Alysseae. Overall, using genome skimming data, we resolved robust phylogenetic relationships of core Brassicaceae and shed new light on the complex evolutionary history of this family.     

The major opsin in bees (Insecta: Hymenoptera): A promising nuclear gene for higher level phylogenetics.

We report the phylogenetic utility of the nuclear gene encoding the long-wavelength opsin (LW Rh) for tribes of bees. Aligned nucleotide sequences were examined in multiple taxa from the four tribes comprising the corbiculate bees within the subfamily Apinae. Phylogenetic analyses of sequence variation in a 502-bp fragment (approx 40% of the coding region) strongly supported the monophyly of each of the four tribes, which are well established from previous studies of morphology and DNA. Trees estimated from parsimony and maximum likelihood analyses of LW Rh sequences show a strongly supported relationship between the tribes Meliponini and Bombini, a relationship that has been found uniformly in studies of other genes (28S, 16S, and cytochrome b). All of the tribal clades as well as relationships among the tribes are supported by high bootstrap values, suggesting the utility of LW Rh in estimating tribal and subfamily rank for these bees. The sequences exhibit minimal base composition bias. Both 1st + 2nd and 3rd position sites provide information for estimating a reliable tree topology. These results suggest that LW Rh, which has not been reported previously in studies of organismal phylogenetics, could provide important new data from the nuclear genome for phylogeny reconstruction.     

Single-copy nuclear genes recover cretaceous-age divergences in bees

We analyzed the higher level phylogeny of the bee family Halictidae based on the coding regions of three single-copy nuclear genes (long-wavelength [LW] opsin, wingless, and elongation factor 1-alpha [EF-1 alpha]). Our combined data set consisted of 2,234 aligned nucleotide sites (702 base pairs [bp] for LW opsin, 405 bp for wingless, and 1,127 bp for EF-1 alpha) and 779 parsimony-informative sites. We included 58 species of halictid bees from 33 genera, representing all subfamilies and tribes, and rooted the trees using seven outgroups from other bee families: Colletidae, Andrenidae, Melittidae, and Apidae. We analyzed the separate and combined data sets by a variety of methods, including equal weights parsimony, maximum likelihood, and Bayesian methods. Analysis of the combined data set produced a strong phylogenetic signal with high bootstrap and Bremer support and high posterior probability well into the base of the tree. The phylogeny recovered the monophyly of the Halictidae and of all four subfamilies and both tribes, recovered relationships among the subfamilies and tribes congruent with morphology, and provided robust support for the relationships among the numerous genera in the tribe Halictini, sensu Michener (2000). Using our combined nucleotide data set, several recently described halictid fossils from the Oligocene and Eocene, and recently developed Bayesian methods, we estimated the antiquity of major clades within the family. Our results indicate that each of the four subfamilies arose well before the Cretaceous-Tertiary boundary and suggest that the early radiation of halictid bees involved substantial African-South American interchange roughly coincident with the separation of these two continents in the late Cretaceous. This combination of single-copy nuclear genes is capable of recovering Cretaceous-age divergences in bees with high levels of support. We propose that LW opsin, wingless, and EF-1 alpha(F2 copy) may be useful in resolving relationships among bee families and other Cretaceous-age insect lineages.     

基于28S rRNA D2序列的内茧蜂亚科的分子系统发育

首次利用同源28S rRNA D2基因序列对内茧蜂亚科Rogadinae （昆虫纲Insecta：膜翅目Hymenoptera：茧蜂科Braconidae）进行了分子系统学研究。本研究从95%～100%乙醇浸渍保存的标本中提取基因组DNA并扩增了10种内群种类和5种外群种类的28S rDNA D2片段并测序（GenBank序列号AY167645-AY167659）,利用BLAST搜索相关的同源序列, 采用了GenBank中13个种类的28S rRNA D2同源序列,然后据此进行分子分析。利用3个外群（共8个种类）和3种建树方法 (距离邻近法distance based neighbor joining, NJ; 最大俭约法maximum parsimony, MP; 和最大似然法maximum likelihood, ML)分析了内茧蜂亚科内的分子系统发育关系。结果表明,由分子数据产生的不同的分子系统树均显示内茧蜂亚科是一个单系群。内茧蜂亚科内依据形态和生物学特征的分群（族和亚族）及其系统发育关系得到部分支持。NJ、MP和ML分析结果均表明内茧蜂族Rogadini不是一个单系,而是一个并系,其余3族则得到不同程度的支持。内茧蜂族可分成2个分支：“脊茧蜂属Aleiodes+弓脉茧蜂属Arcaleiodes”和“沟内茧蜂属Canalirogas+锥齿茧蜂属Conspinaria+刺茧蜂属Spinaria+内茧蜂属Rogas”,二者不是姐妹群。脊茧蜂属Aleiodes和弓脉茧蜂属Arcaleiodes始终是姐妹群。脊茧蜂属Aleiodes是一个单系,并可分成2个姐妹分支,这与依据形态和生物学特征的亚属分群相一致。弓脉茧蜂属Arcaleiodes Chen et He,1991是一个独立的属。分支“沟内茧蜂属Canalirogas+锥齿茧蜂属Conspinaria+刺茧蜂属Spinaria+内茧蜂属Rogas”的单系性仅得到部分分子数据的支持;因形态特异（腹部成甲壳状）而列为亚族级的刺茧蜂属Spinaria,分子分析没有证实这一点。横纹茧蜂族Clinocentrini是个单系,并在内茧蜂亚科的系统发育中处于基部（原始）的位置。我们研究结果还表明,阔跗茧蜂属Yelicones和潜蛾茧蜂属Stiropius相对应的阔跗茧蜂族Yeliconini和潜蛾茧蜂族Stiropiini为2个独立的分支, 与形态和生物学的结果一致,但它们在内茧蜂亚科的系统发育的位置不明,有待今后进一步研究。     

基于28S rDNA D2基因片段与形态特征的优茧蜂亚科系统发育研究

本研究选取优茧蜂亚科Euphorinae(膜翅目Hymenoptera:茧蜂科Braconidae)的8族19属23种作为内群,茧蜂其它6个亚科的8属8种作外群,首次结合同源核糖体28S rDNA D2基因序列片段和41个形态学特征对该亚科进行了系统发育学研究。利用"圆口类"的内茧蜂亚科Rogadinae、茧蜂亚科Braconinae、矛茧蜂亚科Doryctinae的3个亚科为根,以PAUP*4.0和MrBayes3.0B4软件分别应用最大简约法(MP)和贝叶斯法对优茧蜂亚科的分子数据和分子数据与非分子数据的结合体进行了分析;并以PAUP*4.0对优茧蜂亚科的28S rDNA D2基因序列的片段的碱基组成与碱基替代情况进行了分析。结果表明:优茧蜂亚科的28S rDNA D2基因序列片段的GC%含量在40.00%~49.25%之间变动,而对于碱基替代情况来讲,优茧蜂亚科各个成员间序列变异位点上颠换(transversion)大于转换(transition);不同的分析和算法所产生的系统发育树都表明目前根据形态定义出的优茧蜂亚科Euphorinae不是一个单系群,而是一个与蚁茧蜂亚科Neoneurinae和高腹茧蜂亚科Cenocoelinae混杂在一起的并系群;在优茧蜂亚科内部,悬茧蜂族Meterorini和食甲茧蜂族Microctonini(排除猎户茧蜂属Orionis)为单系群,而宽鞘茧蜂族Centistini、大颚茧蜂族Cosmophorini、优茧蜂族Euphorini、瓢虫茧蜂族Dinocampini为并系群;悬茧蜂族Meterorini在优茧蜂亚科Euphorinae内位于基部位置的观点得到部分的支持,同时食甲茧蜂族Microctonini被判定为相对进化的类群。此外对于优茧蜂亚科内各属之间的相互亲缘关系,不同算法所得到的系统发育属的结果不完全一致,这表明优茧蜂亚科内(属及族)的系统发育关系还有待于进一步研究。     

Phylogeny of Gastrotricha: a morphology-based framework of gastrotrich relationships

Currently, the phylum Gastrotricha is divided into the orders Macrodasyida and Chaetonotida, with the structure of the myoepithelial pharynx being an important distinguishing feature. Macrodasyida currently has six recognized families, and Chaetonotida comprises seven families. However, within-group relationships are poorly understood. To arrive at a better understanding of gastrotrich systematics and phylogeny, we performed the first cladistic analysis of nearly all known gastrotrich genera using 71 morphological characters. Results suggest that the Gastrotricha is a monophyletic group (supported by 82% of bootstrap replications) with its most primitive taxa distributed among the families Dactylopodolidae and Neodasyidae. Monophyly of Macrodasyida and Chaetonotida was supported by 90% and 52% bootstrap replications, respectively. Within the Macrodasyida, the families Dactylopodolidae, Turbanellidae, Macrodasyidae, and Thaumastodermatidae all formed monophyletic clades. The families Planodasyidae and Lepidodasyidae were paraphyletic. Among the Chaetonotida, the marine family Xenotrichulidae was monophyletic, supported by 51% of bootstrap replications. A second clade containing all freshwater families was supported by 62% bootstrap values. However, Chaetonotidae were paraphyletic. Using this analysis as a framework, we now can explore possible patterns of evolution within it, and arrive at a consensus of the gastrotrich ground pattern. Moreover, in future molecular studies of metazoan phylogeny, we will be able to select gastrotrich species that are more appropriate representatives of the phylum.     

Phylogenetic reassessment of the five forewing radial-veined tribes of Riodininae (Lepidoptera: Riodinidae)

The relationships among the genera and tribal groupings of Riodininae with five forewing radial veins, and between these and tribes with four forewing radial veins, were examined using a phylogenetic analysis. Using the type species from all sixteen genera in the tribal groupings Eurybiini, Mesosemiini and incertae sedis (a presumed paraphyletic group of loosely related genera), and representatives from the four forewing radial‐veined riodinine tribes, thirty‐five new and traditional characters were coded from adult ecology, wing venation and pattern, the adult head and body, male and female genitalia, and early stage ecology and morphology. The majority of characters are illustrated. Phylogenetic analysis of these data produced five equally most parsimonious cladograms using equal weights and after successive weighting. The strict consensus of these confirms the monophyly of Eurybiini and Mesosemiini as currently conceived, but also indicates several higher‐level relationships not previously hypothesized. Mesosemiini is here more broadly defined to also include the entire incertae sedis section, and the tribe is divided into Mesosemiina, for the previously delimited Mesosemiini plus Eunogyra and Teratophthalma, and Napaeina, subtr.n. for the incertae sedis section minus these two genera. The following hypothesis of relationships is tentatively proposed for the basal clades of Riodininae: Mesosemiini + (Eurybiini + remainder of Riodininae). These new hypotheses, and the characters supporting them, are discussed and compared with those previously proposed.     

Morphological phylogeny of army ants and other dorylomorphs (Hymenoptera: Formicidae)

Abstract. The dorylomorph group of ants comprises the three subfamilies of army ants (Aenictinae, Dorylinae, Ecitoninae) together with the subfamilies Aenictogitoninae, Cerapachyinae, and Leptanilloidinae. We describe new morphological characters and synthesize data from the literature in order to present the first hypothesis of phylogenetic relationships among all dorylomorph genera. These data include the first available character information from the newly discovered male caste of Leptanilloidinae. We used ant taxa from Leptanillinae, Myrmeciinae, and the poneromorph (Ponerinae sensu lato) subfamilies Amblyoponinae, Ectatomminae, and Paraponerinae as outgroups. We scored a total of 126 characters from twenty-two terminal taxa and used these data to conduct maximum parsimony and bootstrap analyses. The single most-parsimonious tree and bootstrap results support a single origin of army ants. The Old World army ant genus Dorylus forms a monophyletic group with the enigmatic genus Aenictogiton, which is currently known only from males; the second Old World army ant genus Aenictus is sister to this clade. This result generates the prediction that females of Aenictogiton, when discovered, will be observed to possess the army ant syndrome of behavioural and reproductive traits. The monophyly of the New World army ants (Ecitoninae) is supported very strongly, and within this group the genera Eciton, Nomamyrmex, and Labidus form a robust clade. The monophyly of Leptanilloidinae is also upheld. The subfamily Cerapachyinae appears paraphyletic, although this conclusion is not supported by strong bootstrap results. Relationships among genera of Cerapachyinae similarly are not resolved robustly, although parsimony results suggest clades consisting of (Acanthostichus + Cylindromyrmex) and (Cerapachys + Sphinctomyrmex). We tested for the effect of incompletely known taxa by conducting a secondary analysis in which the two genera containing ∼50% missing character data (Aenictogiton and Asphinctanilloides) were removed. The strict consensus of the seventeen most-parsimonious trees from this secondary analysis is poorly resolved outside the army ants and contains no clades conflicting with the primary analysis. The position of Leptanilla shifts from forming the sister group to Leptanilloidinae (without high bootstrap support) in the primary analysis, to falling within a polytomy at the base of the root of the dorylomorphs when incompletely known taxa are removed. This instability suggests that the placement of Leptanilla within the dorylomorphs in our primary analysis may be spurious.     

A molecular phylogeny of the grass subfamily Panicoideae (Poaceae) shows multiple origins of C4 photosynthesis

DNA sequence data from the chloroplast gene ndhF were analyzed to estimate the phylogeny of the subfamily Panicoideae, with emphasis on the tribe Paniceae. Our data suggest that the subfamily is divided into three strongly supported clades, corresponding to groups with largely identical base chromosome numbers. Relationships among the three clades are unclear. In unweighted parsimony analyses, the two major clades with x = 10 (Andropogoneae and x = 10 Paniceae) are weakly supported as sister taxa. The third large clade corresponds to x = 9 Paniceae. In analyses under implied weight, the two clades of Paniceae are sisters, making the tribe monophyletic. Neither resolution is strongly supported.Our molecular phylogenies are not congruent with previous classifications of tribes or subtribes. Based on this sample of species, we infer that C(4) photosynthesis has evolved independently several times, although a single origin with multiple reversals and several reacquisitions is only slightly less parsimonious. The phosphoenol pyruvate carboxykinase (PCK) subtype of C(4) photosynthesis has evolved only once, as has the NAD-malic enzyme (ME) subtype; all other origins are NADP-ME. Inflorescence bristles are apparently homologous in the genera Setaria and Pennisetum, contrary to opinions of most previous authors. Some genera, such as Digitaria, Echinochloa, and Homolepis are supported as monophyletic. The large genus Paspalum is shown to be paraphyletic, with Thrasya derived from within it. As expected, Panicum is polyphyletic, with lineages derived from multiple ancestors across the tree. Panicum subg. Panicum is monophyletic. Panicum subg. Dichanthelium, subg. Agrostoides, and subg. Phanopyrum are unrelated to each other, and none is monophyletic. Only Panicum subg. Dichanthelium sect. Dichanthelium, represented by P. sabulorum and P. koolauense, is monophyletic. Panicum subg. Megathyrsus, a monotypic subgenus including only the species P. maximum, is better placed in Urochloa, as suggested by other authors.     

基于叶绿体TrnL- F序列和联合数据分析木通科的分子系统发育(英文)

基于叶绿体trnL_F序列单独分析以及trnL_F和rbcL序列联合分析重建了木通科的分子系统发育。本研究的系统发育拓扑结构与覃海宁和塔赫他间的族划分系统非常一致。猫儿屎族和串果藤族在系统发育树上位于本科的基部。由分布于南美的勃奎拉藤属和拉氏藤属组成的拉氏藤族得到了trnL_F序列分析 (10 0 % )和联合序列分析 (99% )的很好支持。木通族在两个分析里都得到了 10 0 %的靴带支持率。新建立的长萼木通属在trnL_F树上嵌套在木通属内 ;然而 ,在联合分析的树上 ,它与木通属形成姐妹群并得到很高的支持率。在系统发育上关系密切的 3个属 :牛藤果属、八月瓜属和野木瓜属之间的关系仍未解决。牛藤果与八月瓜在两个分析里都形成姐妹群 ,但支持率低。小花鹰爪枫嵌套在野木瓜属内 ,并与西南野木瓜形成姐妹群。木通族内这 3个属可能都不是单系 ,它们的属间界限和属的界定需要更多的分子和形态数据的进一步研究。     

Phylogenetic analysis of chloroplast DNA matK gene and ITS of nrDNA sequences reveals polyphyly of the genus Sonchus and new relationships among the subtribe Sonchinae (Asteraceae: Cichorieae)

Phylogenetic relationships among genera of the subtribes Sonchinae (11 genera and ca. 130 species) and Dendroseridinae (2 genera and 12 species) sensu Bremer were assessed with ITS and matK gene sequences. The Sonchinae is strongly supported as paraphyletic, and subtribal rank of Dendroseridinae is poorly supported. This study re-delimits Sonchinae, which now includes 14 genera and ca. 146 species. Two genera, Reichardia and Launaea, diverge first, followed by a major radiation of the remaining species, including Dendroseris and Thamnoseris. The monotypic Aetheorhiza is more closely related to Sonchus than to Launaea. Sonchus is highly polyphyletic, occurring across nearly all clades of the trees. It is highly probable that several Pacific and Atlantic island endemics evolved within the Sonchus group. Polyploidization processes appear to have played an important role in evolutionary differentiation and speciation in Sonchus, especially in subgenus Sonchus. This study identifies 10 major clades within the Sonchinae, and emphasizes the need to re-delimit and re-circumscribe Sonchus and the Sonchinae.     

Phylogenetic relationships, character evolution, and taxonomic implications within the slipper lobsters (Crustacea: Decapoda: Scyllaridae)

The slipper lobsters belong to the family Scyllaridae which contains a total of 20 genera and 89 species distributed across four subfamilies (Arctidinae, Ibacinae, Scyllarinae, and Theninae). We have collected nucleotide sequence data from regions of five different genes (16S, 18S, COI, 28S, H3) to estimate phylogenetic relationships among 54 species from the Scyllaridae with a focus on the species rich subfamily Scyllarinae. We have included in our analyses at least one representative from all 20 genera in the Scyllaridae and 35 of the 52 species within the Scyllarinae. Our resulting phylogenetic estimate shows the subfamilies are monophyletic, except for Ibacinae, which has paraphyletic relationships among genera. Many of the genera within the Scyllarinae form non-monophyletic groups, while the genera from all other subfamilies form well supported clades. We discuss the implications of this history on the evolution of morphological characters and ecological transitions (nearshore vs. offshore) within the slipper lobsters. Finally, we identify, through ancestral state character reconstructions, key morphological features diagnostic of the major clades of diversity within the Scyllaridae and relate this character evolution to current taxonomy and classification.     

A MOLECULAR PHYLOGENY OF THE GELIDIALES (RHODOPHYTA) BASED ON ANALYSIS OF PLASTID rbcL NUCLEOTIDE SEQUENCES1

Parsimony analyses of rbcL nucleotide. sequences were used to develop hypotheses of relationships among taxa in the taxonomically difficult order Celidiales including species from seven currently recognized genera: Capreolia, Gelidiella, Gelidium, Onikusa, Pterocladia, Ptilophora, and Suhria. Nucleotide. sequences of rbcL from red algae are variable and provide a large number of informative characters for phylogenetic analysis, yet the absence of insertion/deletion mutations allows for the unambiguous alignment of sequences. Species were resolved into 10 well-.supported major clades representing genera and species complexes. The topological positions of these 10 clades within trees are also well supported and indicate that Gelidium and Pterocladia as currently circumscribed are not monophyletic. These results call for a revision of the classification of the Gelidiales .