Phylogenetic placement of Psilopeganum,a rare monotypic genus of Rutaceae (the citrus family) endemic to China

Psilopeganum (Rutaceae) is a rare monotypic genus endemic to the vicinity of the Yangtze River valley in Chongqing, Hubei, Sichuan and Guizhou provinces in China. It differs from most Rutaceae taxa by its herbaceous habit and has been treated as a member of the tribe Ruteae. Our study is the first attempt to place Psilopeganumin a phylogenetic context and our results show that the genus belongs to a clade with Boenninghausenia, Ruta and Thamnosma, which are part of Ruteae. Within this group, the position of Psilopeganum remains unclear because the Boenninghausenia-Thamnosma clade, Psilopeganum and Ruta form a trichotomy in most analyses. The ITS dataset placed Psilopeganum as sister to the Mediterranean and Canarian genus Ruta, which is corroborated by morphological similarities. Our studies support that Ruteae is paraphyletic with respect to Aurantioideae and that Dictamnus does not belong to Ruteae. The Indian, Sri Lankan, and Malagasy genusChloroxylon is sister to the Boenninghausenia-Psilopeganum-Ruta-Thamnosma clade, despite its traditional placement in the subfamily Flindersioideae. The placement of Chloroxylon is consistent with an origin of the group of Chloroxylon, Boenninghausenia, Psilopeganum, Ruta and Thamnosma in southern Asia. The rapid uplifts of the Himalayas could account for one or two vicariance events splitting the lineages of the Boenninghausenia-Psilopeganum-Ruta-Thamnosma clade, and may explain the short branch length and low support for the relationships among Psilopeganum, Ruta, and the Boenninghausenia-Thamnosma clade.     

PHYLOGENETIC POSITION OF BOLBOCOLEON PILIFERUM (ULVOPHYCEAE,CHLOROPHYTA): EVIDENCE FROM REPRODUCTION,ZOOSPORE AND GAMETE ULTRASTRUCTURE,AND SMALL SUBUNIT RRNA GENE SEQUENCES1

Aspects of the reproduction of Bolbocoleon piliferum N. Pringsheim, a common, small, filamentous, endophytic marine green alga, were examined by LM and TEM. These observations were combined with phylogenetic analysis of nuclear‐encoded small subunit rRNA gene sequences to assess the phylogenetic position of B. piliferum. Quadriflagellate zoospores and planozygotes derived from fusion of isogametes yielded plants with identical morphology. Zoosporangia and gametangia divided by sequential cleavages. Plugs at the apices of zoosporangia and gametangia formed during development; tubes were found at zoosporangial and gametangial apices after swarmer release. Flagellar apparatuses of zoospores and gametes were similar to those of algae in the Ulvales (Ulvophyceae), except that terminal caps were entire rather than bilobed and rhizoplasts and “stacked” microtubular root configurations were absent. Structures associated with planozygotes were identical to those observed in other algae currently assigned to Ulotrichales and Ulvales. Molecular phylogenetic analyses placed B. piliferum within the Ulvophyceae, at the base of a clade that contains representatives of the families Ulvaceae, Ulvellaceae, and Kornmanniaceae. The results support an earlier hypothesis that B. piliferum constitutes a distinct lineage. Analyses including Kornmanniaceae recover monophyletic Ulotrichales and Ulvales, whereas analyses omitting the Kornmanniaceae indicate that Ulotrichales is paraphyletic. The structures associated with gamete fusion are conserved within Ulotrichales and Ulvales and perhaps more widely within Chlorophyta.     

Phylogenetic relationships of green algae assigned to the genus Planophila (Chlorophyta): evidence from 18S rDNA sequence data and ultrastructure

Phylogenetic analyses, based upon nuclear small-subunit ribosomal RNA gene sequences, of four ‘chlorosarcinoid’ species referred to Planophila Gerneck show that the genus is polyphyletic. The type species, P. laetevirens Gerneck, is closely related to species in the Ulotrichales, Ulvophyceae. The monotypic sarcinoid genus Pseudendocloniopsis is the closest relative of Planophila; the two genera represent the addition of a new morphological type to the Ulotrichales. Planophila microcystis (Dangeard) Kornmann & Sahling forms a clade at the base of the Ulvophyceae with Oltmannsiellopsis, and thus belongs to the Oltmannsiellopsidales. This result is also supported by the Oltmannsiellopsis-like ultrastructure of P. microcystis zoospores. Planophila sp. B from Antarctica, which has Trebouxia-like pyrenoid structure, is a trebouxiophyte closely related to Chlorella-like unicellular coccoids, Stichococcus bacillaris and Prasiola species. This is the first robustly supported molecular phylogenetic analysis that places Prasiola in the Trebouxiophyceae. As shown previously, P. terrestris Groover & Hofstetter belongs to the Chaetopeltidales, Chlorophyceae. Dangemannia gen. nov. (type species : D. microcystis (Dangeard) comb. nov.), Floydiella gen. nov. (type species : F. terrestris (Groover & Hofstetter) comb. nov.) and Pabia gen. nov. (type: P. signiensis sp. nov.) are proposed.     

Phylogenetic position of endosymbiotic green algae in Paramecium bursaria Ehrenberg from Japan

Endosymbiotic green algae of Japanese Paramecium bursaria were phylogenetically analyzed based on DNA sequences from the ribosomal DNA operon (18S rDNA, ITS1, 5.8S rDNA, and ITS2). Phylogenetic trees constructed using 18S rDNA sequences showed that the symbionts belong to the Chlorella sensu stricto (Trebouxiophyceae) group. They are genetically closer to the C. vulgaris Beijerinck group than to C. kessleri Fott et Nováková as proposed previously. Branching order in C. vulgaris group was unresolved in 18S rDNA trees. Compared heterogeneities of 18S rDNA, ITS1, 5.8S r, and ITS2 among symbionts and two Chlorella species, indicated that the ITS2 region (and probably also ITS1) is better able to resolve phylogenetic problems in such closely related taxa. All six symbiotic sequences obtained here (approximately 4000-bp sequences of 18S rDNA, ITS1, 5.8S rDNA, and ITS2) were completely identical in each, strongly suggesting a common origin.     

Phylogenetic position of a rare loricated green alga, Cephalomonas granulata N. L. Higinb. (Volvocales, Chlorophyceae)

Cephalomonas ( Cp .) granulata N. L. Higinb. (Volvocales, Chlorophyceae), a rare volvocalean phytoflagellate, has recently been isolated from a paddy field in Japan and examined by light and fluorescence microscopy. The vegetative cells of Cp . granulata have granulate loricae and a characteristic mushroom-like shape with a hemispherical to spherical anterior part and narrower posterior part. Cp . granulata has been classified among the Phacotaceae along with other loricated genera. However, its phylogenetic position has not been investigated using molecular phylogeny. To evaluate the phylogenetic position of Cephalomonas , the 18S r RNA gene sequence of the Japanese strain was determined. The phylogenetic analyses revealed that Cp . granulata was not closely related to other loricated taxa with known phylogenetic affinities, such as Phacotaceae sensu stricto ( Phacotus , Pteromonas , and Wislouchiella ) and Dysmorphococcus globosus . This indicates at least three independent origins of loricae within the Volvocales.     

Phylogeographic history of the genus Tropheus,a lineage of rock-dwelling cichlid fishes endemic to Lake Tanganyika

Lake Tanganyika contains the oldest and most complex flock of cichlid fishes counting about 200 endemic species. It is comprised of 16 ecologically, morphologically and genetically highly distinct tribes. Many species are further subdivided into arrays of geographic morphs, each colonizing particular sections of the shore line. The genus Tropheus represents the most spectacular and best studied example for this phenomenon, counting more than 100 distinctly colored populations and sister species, some living in sympatry. Their present distribution and genetic structure was shaped by a series of lake level fluctuations which caused cycles of isolation and secondary admixis. The present study extends previous work on the phylogeography of Tropheus and aims at the fine-scale reconstruction of the origin and spread of lineages in the central and southern basin of the lake. The previously defined mtDNA lineages were evaluated on the basis of statistical parsimony networks. Haplotype networks were created for each lineage and related to their centers of diversity in terms of present distribution. A linearized tree analysis and a mismatch distribution analysis corroborate two of the three radiation waves suggested in earlier works, but the new data suggest a different primary colonization scenario for the southern basin.     

基于多基因分析对我国红曲霉属Monascus真菌的系统发育研究

红曲霉属Monascus具有重要的经济和生态价值,但对该属的物种识别和系统发育学研究有限。本研究首先对红曲霉属红色组内物种开展ITS和LSU序列的测定并综合分析,结合GenBank中相关物种序列及菌株的形态学特征,探讨红曲霉属的系统发育关系,鉴定出红色组3个种,弗罗里达组7个种。其次采用红曲霉色素表型控制基因簇部分基因pksKS序列进行分析,以期解决ITS和LSU等基因序列分析无法有效区分红色红曲与紫色红曲不同形态种的问题。通过分子克隆测序与直接测序结果的比较,以及对3个血红红曲菌株单核苷酸多态性的分析,解析了血红红曲种内遗传差异,首次在红曲霉属真菌中发现疑似红色红曲血红自然杂交种。最后综合ITS、LSU、pksKS序列和形态学分析的结果,统一了红曲霉属内物种的系统发育关系,确认红色组包括3个种：红色红曲M. ruber、紫色红曲M. purpureus、血红红曲M. sanguineus;发现3个变种：红色红曲发白变种M. ruber var. albidulus、紫色红曲橙色变种M. purpureus var. aurantiacus及紫色红曲火红色变种M. purpureus var. rutilus;弗罗里达组包括7个种：弗罗里达红曲M. floridanus、苍白红曲M. pallens、新月红曲M. lunisporas、阿根廷红曲M. argentinensis、累西腓红曲M. recifensis、黄色红曲M. flavipigmentosum、蜂蜜红曲M. mellicola。另外,发现1个疑似杂交种：红色红曲血红杂种M. ruber × sanguineus。结果表明,红曲霉属具有丰富的物种多样性,而且通过多基因和形态学分析可以将相近种区分开来。     

Phylogenetic relationships within the Archiloa genus complex (Proseriata,Monocelididae)

Of the seven genera which we have recognised within the Archiloa genus complex sensu Karling (1966) the cosmopolitan genus Archilina is the most primitive and is characterised only by plesiomorphic characters, and has to be considered paraphyletic. All other species of the Archiloa genus complex are hypothesized to be derived from Archilina-like ancestors through different evolutionary lineages. One lineage led to the genera Archiloa, Inaloa, Archilopsis and Monocelopsis, taxa found in the Atlantic and the Mediterranean. These genera are monophyletic and their relationships are analyzed. The genera Mesoda (Brazil) and Tajikina (Northern Pacific) can be considered as two other separate lineages. Similarly, within what we now consider as the genus Archilina different lineages can be recognized in different regions.     

Ultrastructure and phylogenetic relationships of the unicellular green algae Ignatius tetrasporus and Pseudocharacium americanum (Chlorophyta)

The phylogenetic relationships of two unicellular green algae, Ignatius tetrasporus Bold et MacEntee and Pseudocharacium americanum Lee et Bold were investigated by ultrastructural and molecular methods. The zoospores from both species were covered neither by scales nor cell walls. The flagellar apparatus of the zoospores commonly included these features: the upper basal bodies were displaced counterclockwise in half to two‐thirds of the basal body diameter and did not overlap with each other; the lower basal bodies were directly opposed or slightly displaced clockwise; the distal fiber had gently sigmoid central striations; terminal caps were absent from the ends of the basal bodies; a V‐shaped proximal sheath extended from the upper basal bodies; a posterior fiber lay between the opposite lower basal bodies; and the coarsely striated band linked the sinister rootlet to the lower basal body. The suite of these features was not identical to that of any other quadriflagellate swimming cells, but some features including the lower basal body orientation, the striated distal fiber, and the coarsely striated fiber resemble those of the several organisms of the Siphonocladales sensu Floyd and O’Kelly. Phylogenetic analysis using 18S rDNA sequence data revealed that I. tetrasporus and P. americanum formed a monophyletic clade within the clade of Ulvophyceae sensu López‐Bautista and Chapman, but was not nested within any of the orders of the class that were examined.     

A preliminary list of sublittoral marine algae from the west of Scotland

The valves and girdle bands of Melosira varians C. A. Agardh have been shown to possess greater detail than had been supposed from light microscopy. Spines, pores and projections on the surface of the loculate valve are described, and the precise relationships of the girdle bands to each other and to the valves have been elucidated.     

Phylogenetic relationships in the genus Cheracebus (Callicebinae,Pitheciidae)

Cheracebus is a new genus of New World primate of the family Pitheciidae, subfamily Callicebinae. Until recently, Cheracebus was classified as the torquatus species group of the genus Callicebus. The genus Cheracebus has six species: C. lucifer, C. lugens, C. regulus, C. medemi, C. torquatus, and C. purinus, which are all endemic to the Amazon biome. Before the present study, there had been no conclusive interpretation of the phylogenetic relationships among most of the Cheracebus species. The present study tests the monophyly of the genus and investigates the relationships among the different Cheracebus species, based on DNA sequencing of 16 mitochondrial and nuclear markers. The phylogenetic analyses were based on Maximum Likelihood, Bayesian Inference, and multispecies coalescent approaches. The divergence times and genetic distances between the Cheracebus taxa were also estimated. The analyses confirmed the monophyly of the genus and a well-supported topology, with the following arrangement: ((C. torquatus, C. lugens), (C. lucifer (C. purinus, C. regulus))). A well-differentiated clade was also identified within part of the geographic range of C. lugens, which warrants further investigation to confirm its taxonomic status.     

Phylogenetic position of the spirochetal genus Cristispira.

Comparative sequence analysis of 16S rRNA genes was used to determine the phylogenetic relationship of the genus Cristispira to other spirochetes. Since Cristispira organisms cannot presently be grown in vitro, 16S rRNA genes were amplified directly from bacterial DNA isolated from Cristispira cell-laden crystalline styles of the oyster Crassostrea virginica. The amplified products were then cloned into Escherichia coli plasmids. Sequence comparisons of the gene coding for 16S rRNA (rDNA) insert of one clone, designated CP1, indicated that it was spirochetal. The sequence of the 16S rDNA insert of another clone was mycoplasmal. The CP1 sequence possessed most of the individual base signatures that are unique to 16S rRNA (or rDNA) sequences of known spirochetes. CP1 branched deeply among other spirochetal genera within the family Spirochaetaceae, and accordingly, it represents a separate genus within this family. A fluorescently labeled DNA probe designed from the CP1 sequence was used for in situ hybridization experiments to verify that the sequence obtained was derived from the observed Cristispira cells.     

Phylogenetic systematics of the monotypic genus Hayataella (Rubiaceae) endemic to Taiwan

Hayataella (Rubiaceae) is a monotypic genus endemic to Taiwan that comprises H. michelloides. In recent years, Hayataella was considered to be synonymous with Ophiorrhiza; however, no specific data have been reported, and the systematic treatment of Hayataella has been unclear. To elucidate the systematic treatment of Hayataella, molecular phylogenetic analyses based on ITS of nrDNA, atpB–rbcL, and trnK/matK of cpDNA were conducted with four Ophiorrhiza species. In the Bayesian and the most parsimonious trees, H. michelloides was included in the Ophiorrhiza clade. The monotypic status of Hayataella is, therefore, not considered appropriate, and the combination Ophiorrhiza michelloides (Masam.) H. S. Lo is supported.     

Phylogenetic position of the genus Dobinea: Evidence from nucleotide sequences of the chloroplast gene rbcL and the nuclear ribosomal ITS region

Dobinea Buch.-Ham. ex D. Don, a genus with two species endemic to east Asia, has been placed in three different families, the Podoaceae, tribe Acerineae of the Sapindaceae, and tribe Dobineeae of the Anacardiaceae. In this paper, phylogenetic relationships of the genus were examined based on DNA sequences of the chloroplast rbcL gene and the ITS region of nuclear ribosomal DNA. Our data support the monophyly of Dobinea and its placement in the Anacardiaceae.     

Phylogenetic position of South American Cheilanthes (Cheilanthoideae,Pteridaceae): Advances in the generic circumscription and segregation of the new genus Mineirella

This analysis corroborates and expands our previous results regarding the phylogenetic position of Cheilanthes species from South America. We sequenced three plastid genetic regions, one genic (rbcL) and two genic plus intergenic spacers (trnL + trnL-F and rps4 + rps4-trnS) from 25 South American cheilanthoid species. This allowed us to elucidate phylogenetic relationships that have been historically unresolved or were lowly supported. Here, we analyzed 45 Cheilanthes species (23 from South America) and circumscribed Cheilanthes s.s. in a strongly supported clade that contains three subclades: (i) exclusively from South America, (ii) from Australasia + South America, and (iii) from Africa. The position of three South American species, previously referred to the informal “Cheilanthes geraniifolia group”, is confirmed as a highly supported group outside Cheilanthes s.s. and within the Adiantopsis–Doryopteris clade. This group is described here as the new genus Mineirella. The new combinations for the genus and illustrations are included. Additionally, we discuss the morphological innovations that provide evidence to support the different clades.     

Insect pollination of Musella (Musaceae), a monotypic genus endemic to Yunnan, China

 The pollination biology of Musella lasiocarpa (Franch.) C. Y. Wu ex H. W. Li, a monotypic genus in the banana family (Musaceae) endemic to southwestern China, was investigated. Floral phenology, nectar production, and flower visitors were observed, measured, and recorded. Bagging experiments and comparative breeding system studies were carried out at different study sites and in different seasons. Our results revealed four important aspects of the reproductive biology of Musella. 1) This species blooms year round, but most flowering is concentrated from February to August. The longevity of female flowers is greater than that of male flowers and opening of both types of flowers occurs at anytime during the day, but is concentrated in the morning. 2) Although nectar is produced uniformly while flowers are open, the nectar volume and rate of female flowers are significantly higher than that of male flowers. 3) Insects, such as bumblebees (Bombus eximius and B. montivolans), honeybees (Apis cerana and A. florea), and wasps (Vespa mandarinia) are the primary floral visitors and show a preference for female flowers. 4) Both fruit and seed set are pollinator-limited at both study sites. A comparison of the floral biology and pollination characteristics among the three genera in the banana family suggests that insect pollination has played an important role in the reproductive isolation and breeding system evolution of Musella. Received February 14, 2002; accepted March 26, 2002 Published online: November 22, 2002 Addresses of authors: Aizhong Liu, W. John Kress (correspondence, e-mail: kress.john@nmnh.si.edu), Botany, MRC-166, United States National Herbarium, National Museum of Natural History, Smithsonian Institution, PO Box 37012, Washington DC 20013-7012, USA. Hong Wang, De-Zhu Li (dzl@public.km.yn.cn), Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China.