中国堇菜属美丽堇菜亚属(堇菜科)植物分类学修订

对中国堇菜属美丽堇菜亚属植物进行了系统学修订,确认中国堇菜属美丽堇菜亚属植物共有6种,列出分种检索表,对《中国植物志》51卷中未记载的3种进行了详细的描述,并对塔城堇菜、深紫堇菜及隐距堇菜进行了绘图。     

Viola stoloniflora (Violaceae), a new species from the Ryukyus

Viola stoloniflora Yokota et Higa (Violaceae) is newly described from Okinawa Island, the Ryukyus. This species is characterized by the procumbent stolons, the almost round leaf blades, the densely pilose petioles, the ebarbate white petals with violet veins, and the chromosome number of 2n=22. The present species belongs to Sect.Nomimium, Subsect.Serpentes and is closely related to theV. iwagawai group of Sect.Nomimium, Subsect.Adnatae.     

Viola lilliputana sp. nov. (Viola sect. Andinium, Violaceae), one of the world's smallest violets, from the Andes of Peru

A new violet species of Viola Sect. Andinium, Viola lilliputana, is described from a single dry puna locality on an extensive intermontane plateau southeast of Cerro Palla Palla in the high Andes of Ayacucho Department in southern Peru. This diminutive rosulate violet is evidently among the smallest in the world and probably one of the smallest terrestrial dicots. It belongs to a distinctive species group with pinnatifid leaves that is endemic to central and southern Peru, including V. hillii, V. membranacea and V. weibelii. The new species is similar to V. weibelii in its large, strongly adnate stipules, elongate leaf lobes and dilated unappendaged style with ventral stigmatic orifice. It differs conspicuously from all other members of the pinnatifid-leaved group in its conduplicate leaf blades, straight, mostly nonoverlapping, oblong-lanceolate to broadly elliptical lobes with obtuse to rounded apices, and large basally fused pedicel bractlets. Despite many new collections of vascular plants from the high Andes of Peru and northern Bolivia in recent decades, this distinctive new species is still known only from its type locality, collected on the Iltis-Ugent expedition from November 1962 to January 1963.     

Scrippsiella hexapraecingula sp. nov. (Dinophyceae), a tida pool dinoflagellate from the Northwest Pacific

Specimens of dinoflagellate collected in tide pools along the Pacific coast of central and southern Japan are described as a new species,Scrippsiella hexapraecingula Horiguchi et Chihara, of the Peridiniaceae (Class Dinophyceae). The plate formula is pp, x, 4′, 3a, 6″, 6c, 5‴, 2″" and, 5s, the same as that of other species ofScrippsiella, except in lacking one precingular plate. The genus must be emended, therefore, as having either six or seven precingular plates. This dinoflagellate migrates diurnally. In the morning motile cells are released from non-motile cells attached to the substrate and in the evening the motile cells swim down to settle on the bottom of the tide pool. Attached non-motile cells form either motile mono- or bispores. Sexual reproduction was not observed.     

Characterization of newly developed microsatellite loci in the stemmed yellow violet,Viola pubescens (Violaceae)

Viola pubescens is a perennial herb with a mixed mating system involving the production of both open, chasmogamous flowers and closed, cleistogamous flowers. Using a nonradioactive protocol, 12 microsatellite primers that amplified loci with perfect and imperfect repeats were developed in the species. As examined in five populations of V. pubescens using multiplex reactions, all loci exhibited polymorphism with an average of 5.4 alleles. Most primers also amplified in 12 additional Viola species and one cultivar, revealing the possibility of wide applicability across the genus. This is the first known report of microsatellite loci developed in Viola and the Violaceae.     

Genetic effects of habitat fragmentation in Viola pubescens (Violaceae), a perennial herb with chasmogamous and cleistogamous flowers

The reproductive biology of a plant species is important in the response of populations to habitat fragmentation, especially if plant-pollinator interactions are disrupted. The genetic effects of forest fragmentation were examined in the common understorey herb Viola pubescens, a species that produces self-pollinated cleistogamous (CL) flowers and potentially outcrossing chasmogamous (CH) flowers. Using allozymes, we measured genetic variation in different sized populations. These were located in woodlots of various sizes (0.5-40.5 ha) and distances from one another (0.3-46 km) within the agricultural landscape of central Ohio in the Midwestern United States. Changes in forest cover of each woodlot within the past 180 years were determined from historical sources and aerial photographs. Woodlot and population sizes were significantly and positively correlated with measures of genetic variation (A, P, HO and HE), with variation highest in populations in the largest woodlot population and lowest in the smallest woodlot population. Most large woodlots resulted from fluctuations in forest cover over the past 60 years, while smaller fragments remained the same size. Overall, populations in Crawford County were genetically differentiated from one another (theta = 0.34), but there was no relationship between genetic and geographical distance. Preliminary evidence for a single year indicated a high rate of outcrossing in most populations. Despite the CH/CL reproductive advantage and apparent outcrossing, populations of V. pubescens in small woodlots remain susceptible to potentially detrimental effects of fragmentation such as genetic drift and reduced levels of genetic variation.     

Molecular markers in Viola L. subsect. Viola: Application and taxonomic implications for the identification of dubious herbarium specimens

Abstract

The authors report the use of nuclear [internal transcribed spacer (ITS) sequences 1 and 2] and chloroplast DNA (trnS-trnG intergenic spacer sequences) in Viola subsect. Viola for separate tracking of maternal lineages and detecting dubious herbarium specimens. A phylogenetic investigation carried out on ITS data after removal of all material with possible hybrid origin showed that V. hirta is a monophyletic unit, whereas V. odorata includes at least V. collina and V. jaubertiana, as well as three sequences of V. alba subsp. dehnhardtii from literature. In some, among the sampled individuals, the morphological attribution to one species is contradicted by nuclear DNA, which indicated a wide distance from other non-specific individuals from different locations and closer proximity to a different species. Chloroplast DNA data for the same individuals, on the contrary concurred with morphological evidence. These findings confirm document univocal correlation between our chosen chloroplast sequences and the studied taxa at species or subspecies level; these sequences have the appropriate variability range to be employed for detection of the maternal lineage of unknown Viola samples.     

Two new species of Viola (Violaceae) from the Intermountain West,U.S.A.

Viola lithion andV. franksmithii are rock-dwelling endemics that belong to the North American perennial, caulescent, simple-leaved, blue-, purple-, or white-flowered group of species.Viola lithion, from the White Pine and Pilot mountain ranges of eastern Nevada and adjacent Utah, belongs to sectionChamaemelanium subsectionCanadenses. It most closely resembles the reniform-leaved, Olympic MountainV. flettii, together with which it possibly shares an ancestry with the widespread and allopatricV. canadensis. Viola franksmithii, restricted to the Logan Canyon drainage of the Bear River Range in northern Utah, belongs to sectionRostellatae subsectionRosulantes. It comes closest morphologically toV. howellii of the Coast Range, but likely evolved from the widespreadV. adunca or a common ancestor.     

Genetic and morphological variation in Viola suavis s.l. (Violaceae) in the western Balkan Peninsula: two endemic subspecies revealed

The Balkan Peninsula, with many endemic species, is known as one of the most important speciation and diversification centres in Europe. Here, we present a study of the western Balkan populations of the polymorphic European species, V. suavis s.l., which have been reported under the name V. adriatica, but their taxonomic status and position within the genus have remained uncertain. Viola suavis s.l. and nine close relatives sampled across Europe were subjected to molecular (sequencing of nuclear ribosomal internal transcribed spacers and amplified fragment length polymorphism), karyological and morphometric analyses. Our results revealed the presence of four allopatric, genetically and morphologically differentiated lineages within V. suavis s.l. in Europe, which are suggested here to be recognized at the subspecific rank. Populations from the western Balkans were segregated into two distinct entities: (1) those from north-western Croatia correspond to the previously recognized taxon, V. suavis subsp. adriatica and (2) those from southern Dalmatia (southern Croatia, southern Bosnia and Herzegovina, and south-western Montenegro) are described here as V. suavis subsp. austrodalmatica subsp. nov. The other two lineages of V. suavis s.l., which both harbour blue- and white-flowered morphotypes, occur in central and eastern Europe (V. suavis subsp. suavis) and in north-eastern Spain (plants provisionally treated as V. suavis ‘Spain’). The AFLP and morphological data indicate gene flow between the nominate subspecies and V. suavis subsp. adriatica in a few localities. The distribution of the two western Balkan subspecies is discussed and an identification key to the V. suavis subspecies in Europe is presented.     

Ultrastructure and taxonomy ofJomonlithus littoralis gen. et sp. nov. (Class prymnesiophyceae), a coccolithophorid from the Northwest Pacific

A new coccolithophorid genusJomonlithus withJ. littoralis as the type species, is described based on specimens isolated from a sand sample collected at the mouth of Nakagawa river, Ibaraki, Japan. This genus is characterized by the coccolith which is composed of an organic base-plate scale and calcified rim elements made up of two different subelements.J. littoralis has been found in several localities along the coast of Japan. Culture and ultrastructure studies gave special attention to the cell cycle, coccolith and scale morphology and the ultrastructure of the cellular organelles. It was confirmed thatJomonlithus is similar toWigwamma Mantonet al., Papposphaera Tangen andPappomonas Manton et Oates on the basis of coccolith morphology and toCricosphaera Braarud andHymenomonas Stein in cellular structure.     

Mallomonas canina sp. nov. (Chrysophyceae), a new member of sect. Heterospinae

Mallomonas canina sp. nov. is described from a Danish lake by means of electron microscopy of scales and bristles and compared with the other members of the Mallomonas sect. Heterospinae Momeu & Péterfi.     

Auxosporulation in Chaetoceros acadianus sp. nov. (Bacillariophyceae), a new member of the Section Compressa

We document the fine structure of auxospores in a Chaetoceros species isolated from the Acadian coast of New Brunswick, Canada. Auxospore development in this species occurs in a terminal rather than lateral position, a characteristic never before observed in this genus. Our observations suggest that auxosporulation was uniparental, probably an extreme form of autogamy with sister nuclei fusing following meiosis II. Mature auxospores were adze-shaped to sub-globular and contained both scales and transverse perizonia in their walls. The transverse perizonial band structure was similar to longitudinal perizonial bands found in other species of Chaetoceros and differed from the pinnate bands of pennate transverse perizonia, which consisted of a central rib and bilateral fimbria. Instead, the band structure in C. acadianus was more similar to unilateral fimbriate bands in cymatosiroids. We also propose that our diatom represents a species new to science and is a member of the Chaetoceros Section Compressa. We provide its morphological, molecular and reproductive characterization.     

Population genetic effects of urban habitat fragmentation in the perennial herb Viola pubescens (Violaceae) using ISSR markers

BACKGROUND AND AIMS: Fragmentation of natural habitats can negatively impact plant populations by leading to reduced genetic variation and increased genetic distance as populations become geographically and genetically isolated from one another. To test whether such detrimental effects occur within an urban landscape, the genetic structure of six populations of the perennial herb Viola pubescens was characterized in the metropolitan area of Greater Cincinnati in southwestern Ohio, USA. METHODS: Using three inter-simple sequence repeat (ISSR) markers, 51 loci amplified across all urban populations. For reference, four previously examined agricultural populations in central/northern Ohio and a geographically distant population in Michigan were also included in the analysis. KEY RESULTS: Urban populations retained high levels of genetic variation (percentage of polymorphic loci, P(p) = 80.7 %) with similar genetic distances among populations and an absence of unique alleles. Geographic and genetic distances were correlated with one another, and all populations grouped according to region. Individuals from urban populations clustered together and away from individuals from agricultural populations and from the Michigan population in a principle coordinates analysis. Hierarchical analysis of molecular variance (AMOVA) revealed that most of the genetic variability was partitioned within populations (69.1 %) and among groups (22.2 %) of southwestern Ohio, central/northern Ohio and Michigan groups. Mean F(st) was 0.308, indicating substantial population differentiation. CONCLUSIONS: It is concluded that urban fragmentation does not appear to impede gene flow in V. pubescens in southwestern Ohio. These results are consistent with life history traits of this species and the possibility of high insect abundance in urban habitats due to diverse floral resources and nesting sites. Combined with the cleistogamous breeding system of this species, pollinator availability in the urban matrix may buffer populations against detrimental effects of habitat fragmentation, at least in larger forest fragments. Consequently, it may be inappropriate to generalize about genetic effects of fragmentation across landscapes or even across plant species with different pollination systems.     

Heterorhabditidoides chongmingensis gen. nov., sp. nov. (Rhabditida: Rhabditidae), a novel member of the entomopathogenic nematodes

During a recent soil sample survey in Eastern China, a new entomopathogenic nematode species, collected from the Chongming Islands in the southern-eastern area of Shanghai, was discovered. Morphological characteristics of different developmental stages of the nematode combined with molecular data showed that this nematode is a new genus of Rhabditidae, and described as Heterorhabditidoides chongmingensis gen. nov., sp. nov., for that it shares more morphological characteristics with heterorhabditids than with steinernematids. For males, the papillae formula of bursa is 1, 2, 3, 3, with constant papillae number in the terminal group, stoma tubular-shaped and about 1.5 head width; cheilorhabdions cuticularized, esophageal collar present and long, median bulb present. For infective juveniles, EP = 90 (80-105) μm, ES = 104 (92-120) μm, tail length = 111 (89-159) μm, and a = 19.1 (15-21). The percentages of the nucleotides A, T, C and G in the ITS1 regions of the new species are significantly different from those of heterorhabditids and other rhabditids. Molecular phylogenetic trees based on 18S rDNA and the internal transcribed spacer (ITS) sequences data revealed that the new entomopathogenic nematode species forms a monophyletic group, which is a sister group of the clade comprised of some genera of Rhabditidae.     

Morphological versus genetic diversity of Viola reichenbachiana and V. riviniana (sect. Viola,Violaceae) from soils differing in heavy metal content

Morphological characters, AFLP markers and flow cytometry were used to investigate the morphological and genetic variability and differentiation of Viola reichenbachiana and V. riviniana in non‐metallicolous (NM) and metallicolous (M) populations. The aims were to clarify the taxonomic status of plants occurring in ore‐bearing areas, to determine any relationship in V. reichenbachiana and V. riviniana from sites not polluted with heavy metals, and to examine the genetic variability and differentiation of M and NM populations of both species. Multivariate analyses based on morphological characters showed significant differences between V. reichenbachiana and V. riviniana from non‐polluted sites, high levels of intra‐ and inter‐population variability, and the occurrence of inter‐specific hybrids. Plants from M populations showed hybrid characters but also fell within the range of V. riviniana or V. reichenbachiana. There were no significant differences in relative genome size between plants from polluted areas and V. riviniana from NM populations. Bayesian analysis of population genetic structure based on AFLP markers distinguished two main groups: V. reichenbachiana and V. riviniana together with the M populations. That analysis also revealed the occurrence of populations of inter‐specific hybrids from non‐polluted areas. Further Bayesian analysis of V. riviniana including NM and M populations separated all the studied M populations from NM populations. We conclude that plants forming the M populations are well adapted to a metal‐polluted environment, and could be considered as stabilised introgressive forms resulting from unidirectional (asymmetric) introgression toward V. riviniana.     

山东堇菜属（堇菜科）植物叶表皮微形态的比较研究

利用光学显微镜对山东堇菜属Viola L.20种2变种植物的叶上、下表皮微形态进行了研究。结果表明,该属植物叶表皮细胞为多边形或不规则形,垂周壁为波形、浅波形或平直弓形,气孔器为不等型（偶上表皮兼有平列型）。根据其上表皮是否具有平列型气孔器,可将其分为两个类型,即①上表皮有平列型气孔器,如三色堇;②上表皮无平列型气孔器,如该属绝大多数植物。类型②又根据叶表皮细胞形状和垂周壁式样之不同,进一步划分为4个亚类型。表皮细胞形状和垂周壁式样对该属内种、变种的鉴定具有重要的意义。不赞成将早开堇菜、茜堇菜合并到紫花地丁;不支持将阴地堇菜作为蒙古堇菜的鉴定;不支持将泰山堇菜合并到早开堇菜、将总裂叶堇菜降为裂叶堇菜的变种。     

New distributional and molecular information call into question the systematic position of the West Asian Viola sintenisii (Violaceae)

The west Asian Viola sintenisii W.Becker, described from temperate woodlands of northern Iran and south-western Turkmenistan on the Caspian coast, was long considered a vicariant geographical subspecies of the mainly south European V. alba Besser. The new findings of V. sintenisii in four geographically separated stations in north-eastern Azerbaijan significantly expands its range of distribution. These occurrences are within the range of V. alba ssp. alba . Here the two taxa frequently co-occur but remain distinct and V. sintenisii is therefore justified at species level. It is likely that the two species are also sympatric in the Hyrcanian region, a range previously attributed uniquely to the latter. Viola sintenisii seems to be fairly common in the eastern parts of the Great Caucasus, but there are reasons to suggest that it has there been misinterpreted as V. suavis . The chromosome number of V. sintenisii , 2 n  = 20, is reported here for the first time.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 91–98.     

Mallomonas palaestrica sp. nov. (Synurophyceae), a new member of sect. Torquatae from Denmark

Mallomonas paluestrica sp. nov., a new member of sect. Torquatae ser. Pumilae , was found in a small Danish pond and is described and illustrated with TEM and SEM micrographs.     

Vuilleminia erastii sp. nov. (Corticiales), an amphi-Beringian species and revision of the occurrence of Vuilleminia comedens in North America

Vuilleminia is a basidiomycete genus the species of which have resupinate, corticioid fruiting bodies. It is apparently a North Hemisphere genus, and the majority of its species are distributed in Europe and western Asia. In North America, there are two reports of Vuilleminia comedens. Detailed study of North American specimens and comparisons with additional collections led to the conclusion that they belong to a new lineage named Vuilleminia erastii sp. nov., whose distribution extends from western North America to East Asia, Siberia, and Finland. The species is recognized by the decorticating fruiting bodies with preference for species of Betulaceae in the boreal zone, relatively small allantoid basidiospores, and little-developed cystidia with apical appendix.     

Avrainvillea rotumensis sp. nov. (Bryopsidales, Chlorophyta), a peltate species from the South Pacific

A new species of Avrainvillea was found on the South Pacific island of Rotuma, Fiji. Avrainvillea rotumensis sp. nov. occurs 1.5-3.0 m deep in a high energy current area of the Hoféa Passage, one of the few openings in the fringing reef that surrounds the island. The distinctive peltate growth habit of A. rotumensis is unique for the genus and facilitates quick and accurate field identification. The peltate blade (7–9 cm in diameter at maturity) is unusually thick (34 mm) tapering toward a short (up to 6 cm in length), thick (1.5-2.0 cm in diameter) stipe.