MECHANISMS CONTROLLING NUCLEAR MIGRATION ALONG THE TRICHOGYNE IN THE RED ALGA, BOSTRYCHIA MORITZIANA (RHODOMELACEAE, RHODOPHYTA)

Caloglossa species are widely distributed in mangroves and salt marshes around the world and their life history patterns are being investigated in laboratory culture. In Australia all isolates of C. monosticha , C. postiae and C. ogasawaraensis have Polysiphonia -type (P-type) sexual life histories. Among the 70 C. leprieurii isolates from Australia and New Zealand P-type sexual reproduction also is dominant. However, ten isolates of C. leprieurii from the Spencer Gulf and the Gulf of St. Vincent in South Australia give rise to successive tetrasporphyte generations without gametophytes. Moreover, one isolate from Queensland is asexual. Only one South Australia isolate, obtained from Lake Alexandrina at the mouth of the Murray River, is sexual. South Australia and Pacific Mexico are two regions in which asexual reproduction is dominant. In another mangrove dwelling red alga Bostrychia moritiziana (Rhodomelaceae) non-sexual reproduction also is frequent in Australia, New Caledonia and Bali (Indonesia). This asexual reproductive pattern of tetrasporophytic recycling appears to have arisen independently among individual populations of various red algal species in different regions. Investigations are underway on the molecular phylogeny of the Caloglossa leprieurii isolates.     

Conservation and genetics of the frosted flatwoods salamander (Ambystoma cingulatum) on the Atlantic coastal plain

The federally threatened frosted flatwoods salamander, Ambystoma cingulatum, occurs in isolated populations on the coastal plain of northern Florida, Georgia and South Carolina. An earlier phylogeographic study based primarily on mitochondrial DNA (mtDNA) and morphometrics demonstrated that the previously recognized species A. cingulatum contained two cryptic species, and that two distinct mtDNA clades were contained within the newly restricted A. cingulatum. However, salamanders from the northern extent of the species range in South Carolina were not previously available for analysis. Here, we used individuals from a newly discovered South Carolina breeding site to determine whether A. cingulatum from South Carolina are genetically distinct from their more southerly conspecifics. These analyses included the mitochondrial gene studied previously as well as broad geographic sampling of three rapidly evolving nuclear genes that allowed us to further investigate lineage diversification of flatwoods salamanders. The mitochondrial and nuclear results are largely congruent, yielding strong support for two distinct species of flatwoods salamanders and also two lineages within the eastern species. Further, the South Carolina specimens are closely related to other haplotypes found in eastern Georgia and Florida. Our summary of field surveys over the past 20 years indicates that this South Carolina population may be one of only three remaining in the entire Atlantic coastal plain distribution of this rare and declining amphibian species.     

TOWARD A NATURAL SYSTEM OF SPECIES IN CHLOROGONIUM (VOLVOCALES, CHLOROPHYTA): A COMBINED ANALYSIS OF MORPHOLOGICAL AND rbcL GENE SEQUENCE DATA

The taxonomy of species of Chlorogonium (Volvocales, Chlorophyta) was studied based on comparative light and electron microscopy and DNA sequence data of 23 strains from five major algal culture collections. All of the 23 strains showed pyrenoids under photoautotrophic conditions, but 17 of the 23 exhibited marked reduction in size of pyrenoids, or pyrenoids were absent under photoheterotrophic conditions. The strains could clearly be delineated into six species, C. euchlorum, C. elongatum, C. fusiforme, C. capillatum, C. neglectum, and C. kasakii on the basis of differences in cell shape, number of contractile vacuoles, number and stability of pyrenoids, and ultrastructure of pyrenoids and stigmata. This distinction of species based on morphology was also supported by analyses of rbc L gene sequences. The later strongly showed that each species, C. euchlorum (seven strains), C. elongatum (three strains), and C. capillatum (10 strains), forms a robust clade. Although some morphological differences were noted within different strains of C. euchlorum and C. capillatum, these features were regarded as strain-specific because they were not reflected in the rbc L gene phylogenies. In addition, the rbc L gene trees strongly suggested that C. neglectum and C. kasakii are closely related to each other, consistent with the similarity of the ultrastructure of pyrenoids and stigmata between the two species. However, C. kasakii can be distinguished clearly from C. neglectum by its multiple pyrenoids in the chloroplast and acute anterior and posterior ends in the vegetative cell.     

Bartonella spp. in deer keds, Lipoptena mazamae (Diptera: Hippoboscidae), from Georgia and South Carolina, USA

Deer keds, Lipoptena mazamae (Diptera: Hippoboscidae), were collected from white-tailed deer (Odocoileus virginianus) and humans in Georgia and South Carolina, USA (1 October 2001-6 January 2005) and screened for the presence of DNA from Bartonella spp. Forty deer keds were screened for Bartonella spp. by polymerase chain reaction using primers specific to the riboflavin synthase gene (ribC) of Bartonella. Bartonella species closely related to Bartonella schoenbuchensis and to the etiologic agent of cat-scratch disease (Bartonella henselae) were detected in 10 keds and one ked, respectively.     

中国鞘孢属及其相关类群:鞘孢属新种和新记录种

本文描述了中国鞘孢属Chalara真菌八种,包扩四个新种：间型鞘孢C．intermedia,微小鞘孢Chalara minima,中国鞘孢Chalara sinensis和云南鞘孢Chalara yunnanensis。其余四个种为中国新记录种．文中还提供了所有中国已报道种的检索表．模式标本保存在北京诺维信中国研发中心标本室．     

Conservation genetics of Amorpha georgiana (Fabaceae), an endangered legume of the Southeastern United States

Amorpha georgiana (Fabaceae) is an endangered legume species found in longleaf pine savannas in the Southeastern United States. Approximately 900 individuals and 14 populations remain, most of which are concentrated in North Carolina. Eleven microsatellite loci were used to explore genetic diversity, population structure and recent population bottlenecks using genotypic data from 132 individuals collected at ten different localities. Although A. georgiana is quite rare, it exhibited high levels of genetic diversity (17.7 alleles/locus; H _o = 0.65, H _E = 0.75). Most of the genetic variation was found within rather than between populations of this species. The single remaining Georgia population was well differentiated from populations of the Carolinas ( F _ST > 0.1), which had weaker structure among them ( F _ST < 0.1). Only a geographically disjunct population showed strong evidence of a recent population bottleneck, perhaps due to a recent founder event. Hybridization with A. herbacea was also detected. For conservation management plans, A. georgiana populations in each geographic region (North Carolina, South Carolina and Georgia) plus a disjunct population in North Carolina (Holly Shelter) should be treated as separate management units for which in situ conservation, including habitat restoration and use of prescribed burns, should ensure persistence of this species and preservation of its evolutionary potential.     

EVOLUTIONARY DIVERGENCE IN THE RED ALGAE CALOGLOSSA LEPRIEURII AND C. APOMEIOTICA

Morphological comparisons, hybridization experiments, and molecular phylogenetic analyses using the RUBISCO spacer region were undertaken on 12 populations of Caloglossa leprieurii (Montagne) J. Agardh in order to clarify their relationships. In addition, data from one population of the morphologically similar but asexual species, C. apomeiotica (West et Zuccarello), were included in the assessment. Three morphological types were recognized on the basis of the number of cell rows at nodes of the main axis opposite to the lateral branch and blade width: single/ broad (with three mating groups), multiple/broad (three mating groups) and multiple/slender (one mating group). In the molecular analyses, C. leprieurii was resolved as two clusters that correspond phenetically to the single and multiple cell row types. Both the morphological and molecular data indicate that the asexual species was derived from sexual plants of the multiple cell row type. The reproductive compatibility correlates with genetic distance rather than geographical distance. Sympatric mating groups are completely incompatible and have 10–21 nucleotide changes in the examined region, whereas mating groups that produce abnormal progeny or pseudocystocarps are allopatrically distributed with 5–7 nucleotide changes. The present data suggest that the two populations, one with single and the other with multiple cell rows, which are sympatrically distributed in southeastern Japan, have probably evolved by allopatric speciation. The single/broad type that is restricted to the western Pacific, may have diverged genetically between eastern and western Australia, with subsequent dispersal from the western population as far as Japan.     

Chlamydophila abortus in a Brown skua (Catharacta antarctica lonnbergi) from a subantarctic island

On Bird Island, South Georgia, a new strain of Chlamydophila abortus was detected in one Brown skua out of 37 specimens from six different seabird species. Phylogenetic analysis of the rnpB and omp1 genes indicated the strain to be more closely related to C. abortus than to 6BC, the type strain of Chlamydophila psittaci.     

Hybridization studies in Bostrychia. 1: B. radicans (Rhodomelaceae, Rhodophyta) from Pacific and Atlantic North America

Bostrychia radicans(Montagne) Montagne is a pantropical/temperate red alga associated with mangroves and saltmarsh plants. Collections were made from a similar north-south geographic distribution along both the Pacific and Atlantic coasts of North America. Hybridization studies were performed with cultured isolates to assess the extent of interfertility and reproductive isolation along these two coastlines. All male and female gametophytes derived from single tetrasporophytes were intercompatible. Almost all isolates extending over 1500 km of coast line from northern Pacific Mexico are compatible, forming cystocarps that released viable carpospores. Even isolates which morphologically would be placed in two species [B. radicans and B. moritziana(Sender ex Kützing) J. Agardh], based on the presence or absence of monosiphonous branches, were capable of hybridizing. Crosses of isolates from the Atlantic USA showed a greater amount of incompatibility. Certain isolates were not compatible with any other isolates including isolates collected in close proximity (North Carolina isolates), while other isolates from the same locality were compatible (South Carolina). An isolate from South Carolina formed tetrasporophytes with isolates from Pacific Mexico but tetraspores were not viable. Certain incompatible crosses formed ‘pseudocystocarps’ but viable carposporophytes did not develop. Generalizations about reproductive isolation within a species must also consider differences between populations from different biogeographic regions that may reflect different paleoclimatological histories, founder effects and unique dispersal events.     

POPULATION STRUCTURE AND PHYSIOLOGICAL DIFFERENTIATION OF HAPLOTYPES OF CALOGLOSSA LEPRIEURII (RHODOPHYTA) IN A MANGROVE INTERTIDAL ZONE

Zonation of macroalgae in the intertidal zone has been well documented. However, studies of zonation of macroalgae have predominantly examined the distribution of different species rather than the distribution of variants within a species. This study investigated the spatial variation of plastid haplotypes of the mangrove red alga Caloglossa leprieurii (Montagne) J. Agardh at a site in eastern Australia and tests for physiological differences (growth, photosynthesis) between those haplotypes. RUBISCO spacer plastid haplotypes were scored using single-stranded comformational polymorphism, and the population structure at two sites was examined using a nested sampling design comparing between sites, among transects within sites, and among quadrats within transects. Growth rates at various salinities and light intensities and the photosynthesis–irradiance curves of the three main haplotypes were compared. The two sites showed a high degree of genetic differentiation across a short distance, suggesting limited gene flow. The distribution of haplotypes was patchy and did not reflect a zonation pattern along the intertidal gradient. The three haplotypes were physiologically differentiated with haplotype A, with a lower growth rate and a lower photosynthetic efficiency at higher light intensities. There is some evidence of physiological differentiation between life history phases in C. leprieurii with sporophytes having a higher growth rate than females under most conditions. Our results suggest a correlation between our culture results and our population data. Haplotypes (haplotype A) and life history phases (gametophytes) with lower performance (growth and photosynthetic efficiency) under our culture conditions were correlated with a minor representation in the field. This is the first study to integrate population-level data with physiological parameters toward an understanding of the distribution and relative abundance of red algal genetic variants.     

Dune plant species diversity and function in two barrier island biogeomorphic systems

Barrier island dune systems exhibit strong geographic contrasts in theinteraction between extrinsic disturbance from storm overwash and intrinsicbiogeomorphic recovery processes. To examine how these interactions shape duneplant species diversity, I sampled species cover and topography alongfrequentlystorm-overwashed (South Core Banks, North Carolina) and infrequently overwashed(Sapelo Island, Georgia) barrier islands. The observed compositional anddiversity patterns were in agreement with a complex systems model in whichextrinsic overwash exposure is either reinforced (South Core Banks) or dampened(Sapelo Island) by intrinsic biogeomorphic controls of topography. A largespatial-scale regularity in the distributional pattern of along-shore speciesdiversity was correlated to primary foredune height on South Core. On Sapelo, afine-spatial scale differentiation of species diversity patterns was lessstrongly correlated to topographic metrics. There were no significantdifferences between islands in along-shore alpha diversity (Shannon-Weinerindex). However, Sapelo was more diverse given its smaller area and finer-scalehabitat heterogeneity. I posit that the relevancy of the IntermediateDisturbance Hypothesis is weak when examining diversity patterns along a shoredisturbance gradient. Intrinsic biogeomorphic processes decouple the directcause-and-effect relationship between disturbance and diversity, a basicassumption of IDH. I posit that the Dynamic Equilibrium Model may be a moregenerally applicable conceptual framework. DEM incorporates the interaction ofintrinsic and extrinsic processes that shape habitat heterogeneity, aprerequisite for understanding how complex systems interactions shape diversitypatterns.     

Leaf flavonoid chemistry and taxonomy of Coreopsis sect. Coreopsis

Seventeen flavonoid glycosides were isolated from the leaves of the nine species of Coreopsis sect. Coreopsis. The compounds include two flavones, four flavonols, a 6-hydroxyflavone, a 6-hydroxyflavonol, two 6-methoxyflavones, a 6-methoxyflavonol and three chalcone-aurone pairs. Chemistry distinguishes all species except C. auriculata and C. intermedia. The mean flavonoid similarity for pair-wise comparison of the four species of annuals (C. basalis, C. nuecensis, C. nuecensoides and C. wrightii) is 0.63 whereas it is 0.66 for the five perennial species (C. auriculata, C. grandiflora, C. intermedia, C. lanceolata, C. pubescens) and 0.54 for comparison of annuals with perennials. This indicates that on the average there is slightly higher flavonoid similarity among species of annuals and among species of perennials than there is between annuals and perennials. Lack of the chalcone-aurone pair coreopsin-sulfurein in perennials is the only consistent chemical difference between annuals and perennials. Leaf flavonoid chemistry supports the hypothesis that C. nuecensis and C. nuecensoides are closely related species but flavonoid data are not concordant with the hypothesis of close relationship between C. basalis and C. wrightii, intermedia, Coreopsis pubescens and C. lanceolata are considered closely related and flavonoid chemistry is concordant with this hypothesis. Coreopsis lanceolata is also viewed as closely allied to C. auriculata, but flavonoids suggest the latter species is more similar to C. intermedia. Coreopsis grandiflora is the only perennial species lacking flavonols and has the fewest number of compounds of any species in the section; chemical data support the view that C. grandiflora is quite distinct from other perennial species of sect. Coreopsis.     

深圳香荚兰,首次发现于华南深圳的兰科新种

对兰科新种深圳香荚兰Vanilla shenzhenicaZ．J．Liu＆S．C．Chen作了描述与绘图。此新种为深圳发现的第一个兰科新种,与台湾香荚兰V。somai Hayata有亲缘关系。但是,本新种花序具4花,花较大,不完全开放;唇瓣不裂,紫红色,基部与蕊柱合生长度达3/4,刷状附属物位于唇盘的上部,甚易区别于台湾香荚兰。     

Variation among Populations of Belonolaimus longicaudatus

Three North Carolina populations of Belonolairnus longicaudatus differed significantly from three Georgia populations in stylet measurements, the c ratio, the distance of the excretory pore from the anterior end for both sexes; the a ratio for females only; and the total body length, tail length, and spicule length for males only. The Georgia nematodes were stouter, and the females possessed sclerotized vaginal pieces. The distal portion of the spicules of North Carolina males had an indentation and hump lacking in those of the Georgia males. The haploid number of chromosomes was eight for males from all populations of B. longicaudatus and a North Carolina population of B. maritimus. Interpopulation matings of the Tarboro, N.C. and Tifton, Ga. populations indicated that the offspring produced were infertile. Morphological differences and reproductive isolation suggest that the North Carolina and the Georgia populations belong to different species.     

小叶、中间和柠条三种锦鸡儿的分布式样及其生态适应

确定了小叶锦鸡儿、中间锦鸡儿和柠条锦鸡儿3种植物的分布式样:小叶锦鸡儿为蒙古高原东部-F松辽平原西部-华北山地分布种,中间锦鸡儿为东戈壁-鄂尔多斯高原-黄土高原北部分布种,柠条锦鸡儿为南阿拉善-西鄂尔多斯分布种。小叶锦鸡儿适应分布于蒙古高原典型草原带和森林草原带以及华北山地落叶阔叶林带,在草原带高平原上可形成灌丛化草原的景观,在草原带的沙地上可形成以小叶锦鸡儿为建群种的沙地灌丛植被;中间锦鸡儿适应分布于蒙古高原的荒漠化草原及草原化荒漠带、鄂尔多斯高原的典型草原和荒漠化草原带的沙地及梁地上、黄土高原北部的黄土丘坡上,常形成以中间锦鸡儿为建群种的沙地灌丛植被;柠条锦鸡儿则适应分布于草原化荒漠和典型荒漠带的固定和半固定沙地上。近缘的3种锦鸡儿的地带性分布从东至西或从北向南形成明显的有规律的地理替代分布格局。     

Apteragia pursglovei sp. n. (Trichostrongyloidea: trichostrongylidae) from the white-tailed deer, Odocoileus virginianus.

Two species of Apteragia were found in white-tailed deer (Odocoileus virginianus) from 152 counties in 13 southeastern states. Specimens previously reported as Skrjabinagia odocoilei were reidentified as belonging to 2 similar species of the genus Apteragia, A. odocoilei, and A. pursglovei sp. n. Apteragia pursglovei sp. n. is differentiated primarily by the length, conformation, and degree of sclerotization of the spicules. Of the 824 deer, A. odocoilei occurred in 76.5%, A. pursglovei in 13.8%, both species in 5.0%, and neither in 4.7%. Reassessment of distribution data revealed that only A. odocoilei was present in deer from 99 counties, only A. pursglovei in deer from 25 counties, and both species in deer from 28 counties. Both A. odocoilei and A. pursglovei were found in Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, and Virginia. Apteragia odocoilei also occurred in Maryland, Tennessee, West Virginia, Texas, Oklahoma, New Jersey, and the Virgin Islands.     

Identifying potential keystone species from field data – an example from temporary ponds

Identifying keystone species is essential for understanding community dynamics and preserving species richness. However, few studies have used quantitative, a priori methods to identify potential keystone species. Species known to act as keystones in North Carolina (NC) temporary ponds ( Notophthalmus viridescens , eastern newt, and Siren intermedia , lesser siren) were tested to see whether they played the same role in similar habitats in South Carolina (SC). Newts and sirens had no effect on anuran species richness in SC. Instead, another salamander ( Ambystoma talpoideum , mole salamander) absent from the NC ponds was identified as a strong keystone in SC. It functioned independently of environmental factors and the densities of other predators. Larval dragonflies ( Tramea carolina , Carolina saddlebag) were identified as weak, context-dependent keystones in SC, supporting anuran richness in isolated ponds with very low pH. The results suggest that the identity of keystone species varies, even in similar habitats within a physiographic region.     

Genetical population structure of Trechisibus antarcticus (Coleoptera; Car abidae) on South Georgia and on the Falkland islands

Samples of Trechisibus antarcticus (Coleoptera, Carabidae), collected on South Georgia and the Falkland Islands, were analysed at 8 polymorphic allozyme loci, related to the supposition of a recent arrival of this species on South Georgia. The data showed absence of rare alleles in the South Georgia sample, but otherwise a high similarity between the two populations.