REMARKS ON THE OIOCEROS SPECIES (BOVIDAE, ARTIODACTYLA, MAMMALIA) FROM THE NEOGENE OF CHINA

<正> The genus Oioceros was created by C. Gaillard (1902) based on the species Antilope rothii Wagner, 1857 from the Turolian of Pikermi, Greece. Its diagnosis is that 'Bovidae of small size with long slender muzzle; face bent down on basicranial axis either slightly or to a moderate extent; orbits with expanded orbital roof; horn-cores twisted counter-clockwise in a fairly close spiral of one or two revolutions, widely separate, tilted backward or fairly upright, divergent, with a cross-section almost circular or elliptical, keeled either anteriorly or posteriorly or both; dentition moderately hypsodont, premolar series rather long and slender, molars broad with ribs of medium strength.' (after Pilgrim and Hopwood, 1924, p. 24). Up to now, it has included approximately seventeen species from the Neogene of the Old World (twelve species in Asia, four in Europe and one in Africa).     

Description of a New Species of the Genus Brachytarsophrys Tian and Hu, 1983 （Amphibia： Anura： Megophryidae） from Southern China Based on Molecular and Morphological Data

A new species, Brachytarsophrys popei sp. nov., is described based on a series of specimens collected from Mount Jinggang, Jiangxi Province, Taoyuandong Nature Reserve, Hunan Province and Nanling Nature Reserve, Guangdong Province, China. The new species can be easily distinguished from other known congeners by morphology, morphometrics and molecular data of the mitochondrial 16S rRNA gene. It is characterized by its relatively small size with 86.2 mm in snout-vent length in adult female and 70.7 mm-83.5 mm in males; vomerine teeth bearing on two markedly elevated ridges, which projecting behind far beyond the posterior level of the choanae, widely separated by a distance nearly 1.5 times length of one; margin of tongue de~ply notched behind; toes about one-third to two-thirds webbed in males, at most one-third webbed in female; the webs extending as a wide fringes along either side of toes; upper eyelid with tubercles, one of which is enlarged and becoming a remarkably prominent, bluntly conical light- yellow horn; black tiny nuptial spines on the dorsal surface of the first finger and second finger base, single vocal sac in males; gravid females bear pure yellowish oocytes; tadpoles with a transverse white stripe on ventral surface and two longitudinal white stripes along the sides of body. The new species represents the fifth known Brachytarsophrys species.     

Community characteristics and population structure of Ferrocalamus strictus,a rare species in Mojiang,Yunnan, China北大核心CSCD

Aims As an endangered wild species with extremely small populations, Ferrocalamus strictus is narrowly distributed in South Yunnan with a small number of individuals. The survey of population structure and community characteristics of the wild population of F. strictus can facilitate understanding its endangered system and mechanisms and provide preliminary research basis for its protection. Methods We investigated the community and population structure of F. strictus, including species composition, population density, population survivorship curve and death factors by plot surveying and sampling. Important findings The community in which population of F. strictus is located in Mojiang has some characteristics of mountain rainforests in terms of appearance and species composition. The population density of F. strictus was 2.04 ind.·m–2. The survivorship curve of F. strictus was between Deevey-I and Deevey-II. The net proliferation rate (R0) of F. strictus population was 1.10, which indicates an expanding population of F. strictus. The death of F. strictus is caused by human logging, natural death, shoot degradation and insects feeding. Among them, artificial cutting accounts for the largest proportion. Ferrocalamus strictus is a species of forest bamboos distributed in the South Asian subtropics, which is a medium-sized bamboo species. Its internode length change suddenly from the base 3–4 nodes. The longest ones exceed 1 m, which ranks at the top of all bamboo species and is closely related to its adaptation to the tropical mountain rainforest environment. © Chinese Journal of Plant Ecology.     

Assessing the morphology and ovarian reserve of the ovaries from Mayer-Rokitansky-Küster-Hauser syndrome patients

<正>Dear Editor,Mayer-Rokitansky-Küster-Hauser(MRKH) syndrome is a rare congenital disease characterized by the hypoplastic uterus and vagina in women with a normal female karyotype(46, XX) and phenotype. Although some genes and mutations, such as WNT4, have been reported in a small portion of MRKH syndrome patients(Biason-Lauber et al.,     

Changes in Carboxypeptidase A,Dipeptidase and Na<Superscript>+</Superscript>/K<Superscript>+</Superscript> ATPase Activities in the Intestine of Rats Orally Exposed to Different Doses of Cadmium

The purpose of the present study was to evaluate the effect of cadmium on some protein digestive and absorption enzymes in rats. Thirty-six rats were grouped into three groups of 12 animals each; one group received deionised water and acted as control. One group received 445 μM Cd and the last group received 890 μM Cd in their drinking water for a period of one month. The results obtained indicate that increasing the level of cadmium from 445 μM to 890 μM in the drinking water of the rats led to 29 and 23 increase in accumulated cadmium in the proximal and distal small intestine respectively. The body weight gain of rats exposed to 445 μM and 890 μMCd was decreased by about 24 and 43 respectively when compared with the control. The activities of carboxypeptidase A, dipeptidase and Na+/K+ ATPase were reduced in the mucosa of the proximal end of the small intestine of cadmium exposed rats. The reduction was dose dependent; with the 890 μM Cd exposed rats displaying the least activities. In the distal small intestine, the activities of these enzymes were restored in the 445 μM Cd exposed rats to levels that were not statistically different (P>0.05) from those observed in the controls. In the 890 μMCd exposed rats, dipeptidase activity improved by about 80 compared with the activity of the enzyme in the proximal small intestine. Likewise, Na+/K+ ATPase activity increased by about 125 compared with the observed level in the proximal small intestine. The study suggests that cadmium given to rats in drinking water compromise protein digestion and absorption of nutrients particularly in the proximal region of small intestine and could account for weight reduction associated with cadmium toxicity. Published online December 2004     

Analysis of phytoplankton-zooplankton relationships in an oligotrophic lake under natural and manipulated conditions

During August, 1987, we performed a series of Limnocorral experiments in lake La Caldera, a small winter-kill lake in which phytoplankton is strikingly nutrient-limited. The effects of biomanipulation on zooplankton-phytoplankton relationships were assessed by monitoring both individual species and whole-assemblage responses. Two sizes of enclosures were used (15 and 350 litres) and two treatments were assayed: 1) removal of zooplankton by 45 μm filter net and 2) doubling the natural grazing pressure by increasing the zooplankton concentration. Results show the two enclosure types to differ strikingly: flagellates disappeared from the small enclosures, resulting in four- to six-fold changes in chlorophylla concentration and three- to four-fold changes in number of individuals. Most species were grazed (a prey selectivity based on criteria other than size was observed) and their net growth rate increased with zooplankton concentration, causing a net increase in the phytoplankton growth, a stimulatory effect probably through nutrient regeneration that overrides the losses due to grazing.     

A Highly Pathogenic Strain of Porcine Deltacoronavirus Caused Watery Diarrhea in Newborn Piglets

Porcine deltacoronavirus(PDCoV) is a newly identified virus that causes watery diarrhea in newborn piglets and results in significant economic losses to the pig industry. Since first reported in Hong Kong in 2012, PDCoV has been subsequently detected in USA, South Korea, Thailand, and mainland China. Here we isolated a strain of PDCoV, named CHN-GD-2016,from the intestinal content of a diseased newborn piglet with severe diarrhea in a pig farm in Guangdong, China. PDCoV CHN-GD-2016 could be identified by immunofluorescence with PDCoV specific rabbit antisera, and typical crown-shaped particles with spiky surface projections of this PDCoV were observed with electron microscopy. Genomic analysis showed that the PDCoV CHN-GD-2016 was closely related to other Chinese PDCoV strains, with the highest sequence similarity with the strain CHN/Tianjin/2016. Importantly, inoculation of newborn piglets with 1×10~5 TCID_(50) of CHN-GD-2016 by oral feeding successfully reproduced clear clinical symptoms, including vomiting, dehydration, and severe diarrhea in piglets. In addition, the virus RNA in rectal swabs from 1 to 7 days post inoculation was detected, macroscopic and microscopic lesions in small intestine were observed, and viral antigen was also detected in the small intestines with immunohistochemical staining. Collectively, the data show in this study confirms that PDCoV is present in Guangdong,China and is highly pathogenic in newborn piglets.     

VEGF-specific siRNAs modified with 2′-deoxy effectively suppress VEGF expression and inhibit growth of nasopharyngeal carcinoma xenograft in a mouse model

Vascular endothelial growth factor (VEGF) is up-regulated in the vast majority of human tumors. The up-regulation of VEGF not only plays important roles in tumor angiogenesis, but also provides a target for tumor treatment with small interfering RNA (siRNA) that targets VEGF; however, it is unclear whether a quite high up-regulation of VEGF will affect the efficiency of RNA interference strategies targeting VEGF. A high level expression of VEGF was found in CNE cells from a nasopharyngeal car-cinoma cell line. In this study, we investigate whether VEGF-specific siRNAs can effectively suppress VEGF expression in CNE cells, and study the methods for the use of VEGF-specific siRNAs as potential therapeutic agents. CNE cells with high VEGF expression induced by hypoxia were transfected with VEGF-specific siRNAs. The expression of VEGF was effectively suppressed by VEGF-specific siRNAs, measured by ELISA, Western blot analysis and RT-PCR. Furthermore, experiments in nude mice bear-ing nasopharyngeal carcinoma xenograft were initiated 5 d after injection of CNE cells. VEGF-specific siRNAs were modified with 2′-deoxy, then injected into the tumors, and a liposome-mediated siRNA transfection system and ultrasound exposure were used to help delivery of the siRNAs. Tumor growth was reduced significantly after 3 weeks’ treatment. These studies suggest that VEGF-specific siRNAs still can effectively suppress VEGF expression even in tumor cell lines with a relatively high level of VEGF expression, such as CNE, and VEGF-specific siRNAs modified with 2′-deoxy can be used as po-tential agents for tumor therapy.     

Plastid genomes reveal evolutionary shifts in elevational range and flowering time of Osmanthus (Oleaceae)

Species of Osmanthus are economically important ornamental trees, yet information regarding their plastid genomes (plastomes) have rarely been reported, thus hindering taxonomic and evolutionary studies of this small but enigmatic genus. Here, we performed comparative genomics and evolutionary analyses on plastomes of 16 of the 28 currently accepted species, with 11 plastomes newly sequenced. Phylogenetic studies identified four main lineages within the genus that are here designated the: “Caucasian Osmanthus” (corresponding to O. decorus), “Siphosmanthus” (corresponding to O. sect. Siphosmanthus), “O. serrulatus + O. yunnanensis,” and “Core Osmanthus: (corresponding to O. sect. Osmanthus + O. sect. Linocieroides). Molecular clock analysis suggested that Osmanthus split from its sister clade c. 15.83 Ma. The estimated crown ages of the lineages were the following: genus Osmanthus at 12.66 Ma; “Siphosmanthus” clade at 5.85 Ma; “O. serrulatus + O. yunnanensis” at 4.89 Ma; and “Core Osmanthus: clade at 6.2 Ma. Ancestral state reconstructions and trait mapping showed that ancestors of Osmanthus were spring flowering and originated at lower elevations. Phylogenetic principal component analysis clearly distinguished spring‐flowering species from autumn‐flowering species, suggesting that flowering time differentiation is related to the difference in ecological niches. Nucleotide substitution rates of 80 common genes showed slow evolutionary pace and low nucleotide variations, all genes being subjected to purifying selection.     

Comparative plastome analysis of Blumea,with implications for genome evolution and phylogeny of Asteroideae

The genus Blumea (Asteroideae, Asteraceae) comprises about 100 species, including herbs, shrubs, and small trees. Previous studies have been unable to resolve taxonomic issues and the phylogeny of the genus Blumea due to the low polymorphism of molecular markers. Therefore, suitable polymorphic regions need to be identified. Here, we de novo assembled plastomes of the three Blumea species B. oxyodonta, B. tenella, and B. balsamifera and compared them with 26 other species of Asteroideae after correction of annotations. These species have quadripartite plastomes with similar gene content, genome organization, and inverted repeat contraction and expansion comprising 113 genes, including 80 protein‐coding, 29 transfer RNA, and 4 ribosomal RNA genes. The comparative analysis of codon usage, amino acid frequency, microsatellite repeats, oligonucleotide repeats, and transition and transversion substitutions has revealed high resemblance among the newly assembled species of Blumea. We identified 10 highly polymorphic regions with nucleotide diversity above 0.02, including rps16‐trnQ, ycf1, ndhF‐rpl32, petN‐psbM, and rpl32‐trnL, and they may be suitable for the development of robust, authentic, and cost‐effective markers for barcoding and inference of the phylogeny of the genus Blumea. Among these highly polymorphic regions, five regions also co‐occurred with oligonucleotide repeats and support use of repeats as a proxy for the identification of polymorphic loci. The phylogenetic analysis revealed a close relationship between Blumea and Pluchea within the tribe Inuleae. At tribe level, our phylogeny supports a sister relationship between Astereae and Anthemideae rooted as Gnaphalieae, Calenduleae, and Senecioneae. These results are contradictory to recent studies which reported a sister relationship between “Senecioneae and Anthemideae” and “Astereae and Gnaphalieae” or a sister relationship between Astereae and Gnaphalieae rooted as Calenduleae, Anthemideae, and then Senecioneae using nuclear genome sequences. The conflicting phylogenetic signals observed at the tribal level between plastidt and nuclear genome data require further investigation.     

Allotetraploid origin and divergence in Eleusine (Chloridoideae, Poaceae): evidence from low-copy nuclear gene phylogenies and a plastid gene chronogram

Background and Aims Eleusine

(Poaceae) is a small genus of the subfamily Chloridoideae exhibiting considerable morphological and ecological diversity in East Africa and the Americas. The interspecific phylogenetic relationships of Eleusine are investigated in order to identify its allotetraploid origin, and a chronogram is estimated to infer temporal relationships between palaeoenvironment changes and divergence of Eleusine in East Africa.

Methods

Two low-copy nuclear (LCN) markers, Pepc4 and EF-1α, were analysed using parsimony, likelihood and Bayesian approaches. A chronogram of Eleusine was inferred from a combined data set of six plastid DNA markers (ndhA intron, ndhF, rps16-trnK, rps16 intron, rps3, and rpl32-trnL) using the Bayesian dating method.

Key Results

The monophyly of Eleusine is strongly supported by sequence data from two LCN markers. In the cpDNA phylogeny, three tetraploid species (E. africana, E. coracana and E. kigeziensis) share a common ancestor with the E. indica–E. tristachya clade, which is considered a source of maternal parents for allotetraploids. Two homoeologous loci are isolated from three tetraploid species in the Pepc4 phylogeny, and the maternal parents receive further support. The A-type EF-1α sequences possess three characters, i.e. a large number of variations of intron 2; clade E-A distantly diverged from clade E-B and other diploid species; and seven deletions in intron 2, implying a possible derivation through a gene duplication event. The crown age of Eleusine and the allotetraploid lineage are 3·89 million years ago (mya) and 1·40 mya, respectively.

Conclusions

The molecular data support independent allotetraploid origins for E. kigeziensis and the E. africana–E. coracana clade. Both events may have involved diploids E. indica and E. tristachya as the maternal parents, but the paternal parents remain unidentified. The habitat-specific hypothesis is proposed to explain the divergence of Eleusine and its allotetraploid lineage.     

Molecular phylogenetic evidence supports a new family of octocorals and a new genus of Alcyoniidae (Octocorallia,Alcyonacea)

Molecular phylogenetic evidence indicates that the octocoral family Alcyoniidae is highly polyphyletic, with genera distributed across Octocorallia in more than 10 separate clades. Most alcyoniid taxa belong to the large and poorly resolved Holaxonia–Alcyoniina clade of octocorals, but members of at least four genera of Alcyoniidae fall outside of that group. As a first step towards revision of the family, we describe a new genus, Parasphaerasclera gen. n., and family, Parasphaerascleridae fam. n., of Alcyonacea to accommodate species of Eleutherobia Pütter, 1900 and Alcyonium Linnaeus, 1758 that have digitiform to digitate or lobate growth forms, completely lack sclerites in the polyps, and have radiates or spheroidal sclerites in the colony surface and interior. Parasphaerascleridae fam. n. constitutes a well-supported clade that is phylogenetically distinct from all other octocoral taxa. We also describe a new genus of Alcyoniidae, Sphaerasclera gen. n., for a species of Eleutherobia with a unique capitate growth form. Sphaerasclera gen. n. is a member of the Anthomastus–Corallium clade of octocorals, but is morphologically and genetically distinct from Anthomastus Verrill, 1878 and Paraminabea Williams & Alderslade, 1999, two similar but dimorphic genera of Alcyoniidae that are its sister taxa. In addition, we have re-assigned two species of Eleutherobia that have clavate to capitate growth forms, polyp sclerites arranged to form a collaret and points, and spindles in the colony interior to Alcyonium, a move that is supported by both morphological and molecular phylogenetic evidence.     

Multiple lines of evidence supports the two varieties of Halenia elliptica (Gentianaceae) as two species

Delimiting species requires multiple sources of evidence. Here, we delimited two varieties of Halenia elliptica (Gentianaceae) using several lines of evidence, including morphological traits and mating system in a sympatric population, phylogenetic relationships based on nrITS and cpDNA (rpl16) data, and complete chloroplast genome sequences. Comparative analysis of 21 morphological traits clearly separates the two varieties of H. elliptica. Examination of the flowering process and pollination treatments indicate that H. elliptica var. grandiflora produces seeds via outcrossing, whereas H. elliptica var. elliptica produces seeds via mixed mating. Furthermore, hand-pollinated hybridization of the two varieties produced no seeds. Observations of pollinators showed that when bees began a pollination bout on H. elliptica var. grandiflora they preferred to continue pollinating this variety; however, when they began a pollination bout on H. elliptica var. elliptica, they showed no preference for either variety. Phylogenetic analysis confirmed the monophyly of H. elliptica, which was further divided into two monophyletic clades corresponding to the two varieties. A large number of variants from the chloroplast genomes reflected remarkable genetic dissimilarities between the two varieties of H. elliptica. We recommend that the two varieties of H. elliptica should be revised as two species (H. elliptica and H. grandiflora). Our findings indicate that H. elliptica varieties may have split into two separate species due to a shift in mating system, changes in flowering phenology and/or post-pollination reproductive isolation.     

Six new species of Pythiogeton in Taiwan,with an account of the molecular phylogeny of this genus

Pythiogeton is a little-studied genus of pythialean Oomycete. The genus is characterized by producing its zoospores outside of the sporangium within an apparently naked protoplasmic mass, which formed from a discharge tube-vesicle complex. A total of nine morphologically distinct Pythiogeton species were identified, of which six were new species (Pythiogeton abundans, Pythiogeton microzoosporum, Pythiogeton oblongilobum, Pythiogeton paucisporum, Pythiogeton proliferatum, and Pythiogeton puliensis). A phylogenetic analysis based on internal transcribed spacer sequences revealed that all isolates of Pythiogeton formed a highly supported clade, nested within the wider clade of Pythium species. Each newly recognized Pythiogeton species that was established on the basis of morphological characters was found to occur in a well-supported subgroup within the Pythiogeton clade, confirming their assignment to new species. Pythiogeton shares a common ancestor with the monophyletic group of Pythium species that have predominantly filamentous sporangia rather than with the separate clade of Pythium species that have predominantly globose or ovoid sporangia. This study confirms that Pythium is an extremely heterogenous and polyphyletic genus containing a number of distinct clades of species, including Pythiogeton, which possess morphologically distinguishable characters. A synoptic key to all the described Pythiogeton species is provided.     

Three new species of Liparis s.l. (Orchidaceae: Malaxideae) from Southwest China based on morphological characters and phylogenetic evidence

Liparis aureolabella and L. mengziensis, two new species from the karst region of southwestern China, and L. bingzhongluoensis, a new species from montane region in Yunnan, are described and illustrated. L. aureolabella is easily distinguished from its relatives by having abaxially purple leave with purple reticulate veins prominent adaxially, a lip auriculate at base, and falcate-lanceolate pollinia. Liparis mengziensis is closely related to L. petiolata and L. auriculata, but differs from them by having an ovate to broadly ovate leaf, purple lip and apex connate along the margins. Liparis bingzhongluoensis is similar to Liparis nanlingensis, but the new species is characterized by having a lip with two transparent ridges on its disc, longitudinally concave basal callus and triangular column wings. Phylogenetic analyses based on nuclear ribosomal ITS and plastid matK sequences showed that L. aureolabella and L. mengziensis are nested with L. petiolata or L. auriculata in a monophyletic clade. L. bingzhongluoensis is sister to a clade formed by L. nanlingensis, L. tsii, L. sasakii and L. krameri. Moreover, morphological comparisons strongly support that the three species as separated species newly to science.     

A new species of Aeneator Finlay, 1926 (Mollusca,Gastropoda, Buccinidae) from northern Chile,with comments on the genus and a key to the Chilean species

A new species of the genus Aeneator Finlay, 1926 is described from off the coast of Caldera (27°S), northern Chile. Aeneator martae sp. n. has a small, broad, stout, angulated shell with more prominent axial ribs and a more obviously keeled periphery than all previously named Chilean species. Comparisons are provided with all other South American named species of Aeneator.     

Nitrate competition in a coral symbiosis varies with temperature among Symbiodinium clades

Many reef-building corals form symbioses with dinoflagellates from the diverse genus Symbiodinium. There is increasing evidence of functional significance to Symbiodinium diversity, which affects the coral holobiont''s response to changing environmental conditions. For example, corals hosting Symbiodinium from the clade D taxon exhibit greater resistance to heat-induced coral bleaching than conspecifics hosting the more common clade C. Yet, the relatively low prevalence of clade D suggests that this trait is not advantageous in non-stressful environments. Thus, clade D may only be able to out-compete other Symbiodinium types within the host habitat when conditions are chronically stressful. Previous studies have observed enhanced photosynthesis and fitness by clade C holobionts at non-stressful temperatures, relative to clade D. Yet, carbon-centered metrics cannot account for enhanced growth rates and patterns of symbiont succession to other genetic types when nitrogen often limits reef productivity. To investigate the metabolic costs of hosting thermally tolerant symbionts, we examined the assimilation and translocation of inorganic ¹⁵N and ¹³C in the coral Acropora tenuis experimentally infected with either clade C (sub-type C1) or D Symbiodinium at 28 and 30 °C. We show that at 28 °C, C1 holobionts acquired 22% more ¹⁵N than clade D. However, at 30 °C, C1 symbionts acquired equivalent nitrogen and 16% less carbon than D. We hypothesize that C1 competitively excludes clade D in hospite via enhanced nitrogen acquisition and thus dominates coral populations despite warming oceans.     

Further support for the phylogenetic relationships within Euphorbia L. (Euphorbiaceae) from nrITS and trnL–trnF IGS sequence data

The cosmopolitan genus Euphorbia is one of the largest plant genera with an extreme phenotypic plasticity ranging from globose succulents to large shrubs and trees adapted to very divergent habitats like forests or deserts. We compiled the current knowledge about the evolution of Euphorbia by reconstructing a molecular phylogeny based on nearly all available internal transcribed spacer (nrITS) sequence data from previous investigations and sequences of newly sampled species. We compared the results with phylogenetic analyses based on a combined data set of nrITS and trnL–trnF intergenic spacer sequences of a subset of taxa. Apart from a few exceptions, the results correspond well to recently published studies based on different molecular markers. The genus Euphorbia is divided into four major clades, of which the clade comprising subgen. Rhizanthium is restricted to Africa and Madagascar, whereas the remaining three clades are distributed over several continents. Our results support the hypothesis that Euphorbia evolved in Africa from progenitors of subgen. Esula.