Scale bearing chrysophytes from Papua New Guinea

The scaled chrysophytes from Papua New Guinea were studied for the first time. Twenty two taxa of Chrysophyceae and Synurophyceae are reported. Species diversity was highest in black- and mixed water lakes and swamps of the Sepik floodplain. Most surprisingly. the oligotrophic highland lakes were very poor in chrysophytes.     

Synurophyceae from the Southern Atlantic Coastal Plain of North America: A preliminary survey in Louisiana, USA

Forty-three taxa of Synurophyceae were identified by means of transmission electron microscopy of samples from ten different localities in southeastern Louisiana, USA, on the southern portion of the Atlantic Coastal Plain Province of North America. Samples were collected during a one month period when water temperatures ranged from 15.5–24.5"C. Sample pH values ranged from 4.4–7.2. Notable scale morphology variation was described for some taxa. The flora included three warm water taxa but was dominated by temperate and cosmopolitan taxa. Mallomonas prora and Synura australiensis are reported for the first time from North America. Comparisons with related studies from New World subtropical regions in Florida, USA, and Argentina were made, and significant North American range expansions were noted. The large number of aquatic habitats, 7–8 consecutive months at temperatures (6–20°C) best suited for development of synurophycean populations, and proximity to major bird migrations routes are postulated as explanations for the large number of reported species.     

The relationship between sedimentary chrysophyte scales (Chrysophyceae and Synurophyceae) and limnological characteristics in 25 Norwegian lakes

The relationship between 16 taxa of chrysophyte scales (Chrysophyceae and Synurophyceae) from the surface sediments of 25 soft-water Norwegian lakes and 16 limnological variables from these lakes was examined using canonical correspondence analysis (CCA). The Norwegian chrysophyte flora reported in this study is typical of assemblages described from acidic to circumneutral lakes. Lake-water pH was the environmental variable that explained the most variation in the weighted averages of the chrysophyte taxa, although total aluminium, colour, and specific conductivity were also important. Predictive models were developed to infer lake-water pH based on species composition of chrysophyte scales in the 25 lakes, using weighted averaging regression and calibration with and without tolerance down-weighting. Model performance was evaluated by a computer-intensive bootstrapping procedure to derive root mean squared errors of predictions. In our data set, tolerance corrected weighted average regression and calibration was shown to be a more reliable predictor of pH than simple weighted averaging. This study shows that the remains of chrysophyte scales in Norway can be used as palaeo-biological indicators of lake-water pH.     

Mallomonadaceae (Chrysophyceae) from Malaysia and Australia

The Mallomonadaceae (Chrysophyceae) of Malaysia and Australia are described by scanning and transmission electron microscopy. Thirty taxa are reported from Malaysia, twenty eight for the first time. Eighteen taxa are reported from Australia, twelve for the first time. Twelve taxa are reported for the first time from the tropics. Four new taxa, Mallomonas ocellata sp. nov., M. tropica sp. nov., M. favosa f. gemina f. nov. and Chrysosphaerella astrea sp. nov. are described and the diagnosis of Mallomonas adamas Harris et Bradley is emended.     

Silica‐scaled chrysophytes from Abisko (Swedish Lapland)

The silica‐scaled chrysophyte flora of Swedish Lapland (near Abisko) was examined. Chrysophyte scales were found in 18 of the 32 investigated water bodies (lakes and pools). Altogether, 28 taxa from the classes Chrysophyceae and Synurophyceae were found. The most abundant species was Synura echinulata. Three species were observed for the first time in Sweden: Mallomonas maculata, M. rasilis and Spiniferomonas serrata.     

CHROMOSOME NUMBERS IN UMBELLIFERAE. III

Chromosome numbers are reported for 156 collections representing 100 taxa of Umbelliferae. Approximately two thirds of the collections are from Mexico, Central and South America and indicate a high percentage of polyploid species in certain genera found in this area. Chromosome numbers for plants belonging to 78 taxa are published here for the first time, previously published chromosome numbers are verified for 18 taxa and chromosome numbers differing from those previously published are reported in seven instances. No chromosome counts have been previously published for nine of the genera included here. Further aneuploidy and polyploidy were found in Eryngium, and Lomatium columbianum has been found to be a high polyploid with 2n = 14x. Every chromosome count is referable to a cited herbarium specimen.     

Genetic Bottlenecks in Time and Space: Reconstructing Invasions from Contemporary and Historical Collections

Herbarium accession data offer a useful historical botanical perspective and have been used to track the spread of plant invasions through time and space. Nevertheless, few studies have utilised this resource for genetic analysis to reconstruct a more complete picture of historical invasion dynamics, including the occurrence of separate introduction events. In this study, we combined nuclear and chloroplast microsatellite analyses of contemporary and historical collections of Senecio madagascariensis, a globally invasive weed first introduced to Australia c. 1918 from its native South Africa. Analysis of nuclear microsatellites, together with temporal spread data and simulations of herbarium voucher sampling, revealed distinct introductions to south-eastern Australia and mid-eastern Australia. Genetic diversity of the south-eastern invasive population was lower than in the native range, but higher than in the mid-eastern invasion. In the invasive range, despite its low resolution, our chloroplast microsatellite data revealed the occurrence of new haplotypes over time, probably as the result of subsequent introduction(s) to Australia from the native range during the latter half of the 20^th century. Our work demonstrates how molecular studies of contemporary and historical field collections can be combined to reconstruct a more complete picture of the invasion history of introduced taxa. Further, our study indicates that a survey of contemporary samples only (as undertaken for the majority of invasive species studies) would be insufficient to identify potential source populations and occurrence of multiple introductions.     

Contributions to the Cladocera fauna from Papua New Guinea

Twenty-eight taxa of the Cladocera are identified in collections from Papua New Guinea, 17 being new records for New Guinea, bringing the total number of Cladocera taxa reported for this region to 39. Most of the taxa are circumtropical. One species (Sarsilatona papuana) is endemic to Papua New Guinea and northern Australia. The species list includes two species that are normally listed as Holarctic:Alonella nana andAlona rustica. Widespread genera such asDaphnia, Pleuroxus, Disparalona, Acroperus were strikingly absent from the Papua New Guinean material.     

The taxonomy of problematic Mallomonas species (Synurophyceae). I. Mallomonas hindonii and M. canina

Whole cells with complete cell armour (siliceous scales and bristles) of Mallomonas hindonii and Mallomonas canina (Synurophyceae) have been found in Ontario. It is concluded that these two species are not synonymous, as has been suggested previously, and attention is given to structural features of scales and bristles which can be used to distinguish between them. Both species are restricted to softwater/acidic environments.     

CHROMOSOME NUMBERS IN UMBELLIFERAE. IV.

Chromosome numbers are reported for 167 collections representing 100 taxa of Umbelliferae. More than four-fifths of the counts apply to members of subfamilies Hydrocotyloideae (29) and. Saniculoideae (50); the remaining 21 belong to Apioideae. Chromosome numbers of plants belonging to 68 taxa are published here for the first time; chromosome numbers are verified for 23 taxa; and chromosome numbers differing from those published previously are reported in nine instances. No chromosome counts have previously been reported for 19 of the genera included. Polyploidy has been established for Azorella, Mulinum, Coaxana, Enantiophylla, and Tiozimia.     

PHYLOGENETIC RELATIONSHIPS OF GELIDIALES SPECIES IN COSTA RICA

Despite a general paucity of studies on marine algae in Costa Rica, within the red algal order Gelidiales, 9 species are reported from the Caribbean, and 6 species from the Pacific. In this study 5 species from the southeast Caribbean coast and 2 species from the northwest Pacific coast of Costa Rica were collected for DNA sequence and morphological analyses. At the time of this writing, morphological observations of four Caribbean taxa have identified them as Gelidium microdonticum , Pterocladiella capillacea , P. melanoidea , and Gelidiella acerosa. In rbc L sequence analyses, Gelidium microdonticum is resolved within a clade of small Gelidium species predominantly found in the south Atlantic. Two collections representing different forms of Pterocladiella melanoidea sensu Dawson were found to have identical rbc L sequences. These samples were resolved in rbc L trees with a taxon from Texas identified as P. bartlettii and not P. melanoidea from Europe. Comparisons with type material are being made to verify these identifications so that the status of P. melanoidea in the Caribbean may be determined. The unidentified Caribbean taxon is resolved as a distinct species within the Pterocladiella clade as well. Gelidiella acerosa from Caribbean Costa Rica is closely allied with other Caribbean G. acerosa samples in rbc L trees. The two pacific taxa are small intertidal turf species and have not yet been identified. Sequence analyses resolve these taxa within a large clade of Indo-Pacific and Caribbean Gelidium species.     

The rare species <Emphasis Type="Italic">Synura lapponica</Emphasis> (Synurophyceae) new to the Czech Republic,local vs. global diversity in colonial synurophytes

Synura lapponica Skuja, a freshwater colonial flagellate (Synurophyceae, Stramenopila), has been reported for the first time in the Czech Republic. This study evaluates the ecological requirements of the species, and includes a survey of the literature. Although S. lapponica has been reported thus far only in the Northern Hemisphere, the probability of its bipolar distribution is relatively high (22%). Distribution is probably ecologically determined, water temperature (correlated with latitude or seasonal fluctuations), and lower pH seem to be the primary environmental variables. A local vs. global ratio reflects, to a certain extent, the degree of sampling effort expended in the studied area, but a considerable increase in the number of revealed taxa was apparent when the area was expanded.     

Cytotaxonomy and evolution in Pennisetum section Brevivalvula (Gramineae) in tropical Africa

Chromosome numbers, meiotic pairing configurations, and fertility data are reported for 57 African collections representing five of the six taxa currently recognized in Pennisetum section Brevivalvula. All collections were polyploid from a basic number of x = 9 and exhibited high lrequencies of multivalents at metaphase I. Four of the five taxa include chromosomal races, either through aneuploidy or multiple polyploid levels. Data concerning pollen fertility and seed set suggest that agamospermy is present in these five taxa. Three taxa may be polymorphic for sexual reproduction. Integration of evidence concerning chromosomal and morphological variation in the section suggests possible hybrid origins for three of the six taxa.     

A global perspective for biodiversity history with ancient environmental DNA

The past centuries have seen tremendous turnovers in species distributions and biodiversity due to anthropogenic impacts on a global scale. The processes are ongoing and mostly not well documented. Long‐term records of biotic change can be recovered from sedimentary deposits, but traditional analyses were restricted to organisms that leave behind visible traces and molecular genetic tools were mostly employed on samples that promised good DNA preservation. In this issue of Molecular Ecology, Shaw, Weyrich, Hallegraeff and Cooper (2019) and Gomez Cabrera et al. (2019) present two studies on marine sedimentary records from warm environments, in which they successfully analyze ancient environmental DNA (aeDNA) on a decadal and centennial scale. Notably, the studies were conducted on novel samples with nonoptimal preservation conditions for ancient DNA ‐ historical collections of ship ballast tank sediments from Australia and two coral reef cores spanning up to 750 years (Figure 1) ‐ but yielded a high diversity of taxa. This highlights that aeDNA is a promising tool to globally study biodiversity history on scales of decades to centuries ‐ the timeframe most relevant to human society in the context of both current climate change and direct anthropogenic modifications of the environment.     

Radiation of the Australian flora: what can comparisons of molecular phylogenies across multiple taxa tell us about the evolution of diversity in present-day communities?

The Australian fossil record shows that from ca. 25 Myr ago, the aseasonal-wet biome (rainforest and wet heath) gave way to the unique Australian sclerophyll biomes dominated by eucalypts, acacias and casuarinas. This transition coincided with tectonic isolation of Australia, leading to cooler, drier, more seasonal climates. From 3 Myr ago, aridification caused rapid opening of the central Australian arid zone. Molecular phylogenies with dated nodes have provided new perspectives on how these events could have affected the evolution of the Australian flora. During the Mid-Cenozoic (25-10 Myr ago) period of climatic change, there were rapid radiations in sclerophyll taxa, such as Banksia, eucalypts, pea-flowered legumes and Allocasuarina. At the same time, taxa restricted to the aseasonal-wet biome (Nothofagus, Podocarpaceae and Araucariaceae) did not radiate or were depleted by extinction. During the Pliocene aridification, two Eremean biome taxa (Lepidium and Chenopodiaceae) radiated rapidly after dispersing into Australia from overseas. It is clear that the biomes have different histories. Lineages in the aseasonal-wet biome are species poor, with sister taxa that are species rich, either outside Australia or in the sclerophyll biomes. In conjunction with the fossil record, this indicates depletion of the Australian aseasonal-wet biome from the Mid-Cenozoic. In the sclerophyll biomes, there have been multiple exchanges between the southwest and southeast, rather than single large endemic radiations after a vicariance event. There is need for rigorous molecular phylogenetic studies so that additional questions can be addressed, such as how interactions between biomes may have driven the speciation process during radiations. New studies should include the hitherto neglected monsoonal tropics.     

妙趣横生的滇产珊瑚菌类及其新种(英文)

一九八三年九月,作者对西双版纳勐仑附近进行了为期五天的真菌调查采集。路过思茅时,偶在市场上购得数枚食用真菌,经研究后,其中珊瑚菌类不少与印度、南亚、中南美洲等热带高山地区的种类相比,既有系统上的联系,又有个体上的不同,既有热带成分的共性,又有本地区物种的特性。本文对该地区珊瑚菌类确立了如下六个新分类单位:裂枝滑瑚菌Aphelaria lacerata Petersenet Zang,中华地衣棒瑚菌Multiclavula sinensis Petersen et Zang,淡红丛枝瑚菌Ramaria hemi-rubella Petersen et Zang,印滇丛枝瑚菌Ramaria indo-yunnaniana Petersen et Zang,红柄丛枝瑚菌Ramaria sanguinipes Petersen et Zang,紫褐丛枝瑚菌亚洲变种Ramaria violaceibrunnea var.asiatica Petersen et Zang.文中并讨论了中国新记录的湿生地衣棒瑚菌Multiclavula fossicolal(Corner)Petersen.文中所用缩写其意思如下:E=孢子长度大于阔度的倍数;L_m=孢子长度平均值;E_m=孢子阔度平均值。     

A PHYLOGENETIC ANALYSIS OF THE SYNUROPHYCEAE USING MOLECULAR DATA AND SCALE CASE MORPHOLOGY

The phylogeny of the Synurophyceae was investigated by parsimony analysis of scale case characters and small-sub unit (18S) ribosomal RNA (rRNA) sequence data. Analysis of 1 eustigmatophycean (outgroup), 3 chrysophycean, and 10 synurophycean 18S rRNA sequences corroborated the inference from ultrastructural information that the Synurophyceae is a monophyletic assemblage . Tessellaria vol-vocina, which had been tentatively proposed as a member of the Synurophyceae, was confirmed as the earliest lineage within the Synurophyceae by both the molecular analysis and an evaluation of published ultrastructural data. A second set of analyses investigated the relationships among Tessellaria volvocina, 6 Synura species, and 10 Mallomonas species/varieties, with particular reference to the validity of current classifications of the Synurophyceae and the characters upon which they are based. The molecular and scale case phylogenies were not totally resolved but were largely congruent. The data sets were combined to produce another phylogeny, which showed greater resolution. The combined phylogeny weakly supported our representatives of Synura and Mallomonas as monophyletic groupings and also upheld several of the sections within these genera that are recognized by current classifications. However, some changes to the classification and delineation of these genera are recommended and predicted. Both our 18S rRNA sequence and scale case data sets were more appropriate for examining the branching order among the more closely related text rather than resolving the deeper branching points of the synurophycean phylogeny .