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1.
The species composition of centric diatoms from Lake Frolikha (Transbaikal area) has been studied. The lake is located on the eastern shore of Lake Baikal and connected with it by a river. Twenty-three species of Centrophyceae from 7 genera (Aulacoseira, Cyclostephanos, Cyclotella, Discostella, Handmania, Pliocaenicus, and Stephanodiscus) have been found. The most represented genus is Aulacoseira (11 species). Fifteen species and 4 genera are new for the lake record. All revealed species are known in other lakes of the Baikal region; however Baikal endemics are absent in Lake Frolikha. The flora of centric diatoms in Lake Frolikha can be divided into two groups. The first group includes taxa common in Lake Baikal, and the second group includes taxa not typical for Lake Baikal. The level of differences between flora in Lake Baikal and Lake Frolikha is high (43%) despite the close location and connection to the river. An analysis of distribution of interesting species in Asia is presented.  相似文献   

2.
The native Asian oyster, Crassostrea ariakensis is one of the most common and important Crassostrea species that occur naturally along the coast of East Asia. Molecular species diagnosis is a prerequisite for population genetic analysis of wild oyster populations because oyster species cannot be discriminated reliably using external morphological characters alone due to character ambiguity. To date there have been few phylogeographic studies of natural edible oyster populations in East Asia, in particular this is true of the common species in Korea Cariakensis. We therefore assessed the levels and patterns of molecular genetic variation in East Asian wild populations of C. ariakensis from Korea, Japan, and China using DNA sequence analysis of five concatenated mtDNA regions namely; 16S rRNA, cytochrome oxidase I, cytochrome oxidase II, cytochrome oxidase III, and cytochrome b. Two divergent C. ariakensis clades were identified between southern China and remaining sites from the northern region. In addition, hierarchical AMOVA and pairwise Φ ST analyses showed that genetic diversity was discontinuous among wild populations of C. ariakensis in East Asia. Biogeographical and historical sea level changes are discussed as potential factors that may have influenced the genetic heterogeneity of wild C. ariakensis stocks across this region.  相似文献   

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Peninsular Malaysia is a strategic region which might have played an important role in the initial peopling and subsequent human migrations in Asia. However, the genetic diversity and history of human populations—especially indigenous populations—inhabiting this area remain poorly understood. Here, we conducted a genome-wide study using over 900,000 single nucleotide polymorphisms (SNPs) in four major Malaysian ethnic groups (MEGs; Malay, Proto-Malay, Senoi and Negrito), and made comparisons of 17 world-wide populations. Our data revealed that Peninsular Malaysia has greater genetic diversity corresponding to its role as a contact zone of both early and recent human migrations in Asia. However, each single Orang Asli (indigenous) group was less diverse with a smaller effective population size (N e) than a European or an East Asian population, indicating a substantial isolation of some duration for these groups. All four MEGs were genetically more similar to Asian populations than to other continental groups, and the divergence time between MEGs and East Asian populations (12,000—6,000 years ago) was also much shorter than that between East Asians and Europeans. Thus, Malaysian Orang Asli groups, despite their significantly different features, may share a common origin with the other Asian groups. Nevertheless, we identified traces of recent gene flow from non-Asians to MEGs. Finally, natural selection signatures were detected in a batch of genes associated with immune response, human height, skin pigmentation, hair and facial morphology and blood pressure in MEGs. Notable examples include SYN3 which is associated with human height in all Orang Asli groups, a height-related gene (PNPT1) and two blood pressure-related genes (CDH13 and PAX5) in Negritos. We conclude that a long isolation period, subsequent gene flow and local adaptations have jointly shaped the genetic architectures of MEGs, and this study provides insight into the peopling and human migration history in Southeast Asia.  相似文献   

5.
The ectoparasitic mite Dorsipes caspius n. sp. (Heterostigmata: Podapolipidae) belonging to the platysmae species group collected from the beneath elytra of Pterostichus (Lyrothorax) caspius (Menetries) (Coleoptera: Carabidae) in northern Iran, is described. This is the first record of species of the platysmae group from the Middle East. Keys to adult and larval female stages of world species of the platysmae group are provided. The host range of all species of the genus and the distribution of all representatives of the group are discussed.  相似文献   

6.
Collections from French Guiana, Amazonian Brazil, and Colombia taken in the last 20 years include new species in the following genera:Duroia, Pagamea, Psychotria, Randia, Retiniphyllum, Rudgea, Sabicea, Sipanea, andSphinctanthus. Twenty-one new species are described and five are illustrated.  相似文献   

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A species Schizoblastosporion starkeyi-henricii is common in peats and peaty soils. Fifteen strains of this species isolated from Europe and East Falkland Island were found homogenous in cultural, morphological and physiological characters, with the exception of one strain that was sensitive to elevated osmotic pressure. Analyses of the D1/D2 region of the 26S rDNA and internal transcribed spacers (ITS) confirm that these strains and also Asian isolates are conspecific. Our results show that ecological factors but not geographic distances determine the global distribution of yeast fungi.  相似文献   

10.
Of the many types of freshwater bodies across Iceland (e.g., lakes, springs, rivers, and ponds), greater effort has been invested in researching the freshwater Crustacea (Cladocera, Copepoda) of more permanent, larger, and deeper water bodies than on smaller or more ephemeral sites. To address this, we described the fauna of 12 shallow freshwater bodies distributed from the coast to the central highlands of Iceland. We identified 16 species in 11 genera belonging to six families of Cladocera, and 12 species in eight genera belonging to four families of Copepoda. Five of the species we identified (Alona werestschagini, Cyclops vicinus, Daphnia cristata, Diacyclops abyssicola, and Heterocope borealis) represent new distribution records for Iceland, increasing the number of species now known from this region to 34 Cladocera and 38 Copepoda taxa. Additionally, we discuss the taxonomy of some species with doubtful taxonomical status. Six crustacean taxocenes are described, each characterized by the dominance of different taxa, with bottom sediment characteristics best explaining species assemblage structure. We evaluated the relationships between Icelandic Cladocera and Copepoda faunas and those of the adjacent Svalbard, Faroe, and Shetland Islands, Greenland, and the mainland Norway. The taxonomic composition of the Icelandic fauna is dominated by widely distributed Holarctic, and secondarily Palaearctic and Nearctic species, and is more similar to the faunas of the major North Atlantic islands (64.2–71.8 % similarity) than it is to that of continental Norway.  相似文献   

11.
In the course of ethnobotanical and ethnoarchaeological studies in the Ok Tedi region, Kiunga subprovince, Western Province, Papua New Guinea, Debra Donoghue collected several botanical specimens as vouchers for her studies into the prehistory of edible-nut pandans in the New Guinea Highlands and for David Hyndman’s study of the use and names of pandans in the region. These specimens were submitted to me through Dr. Hyndman for identification, and one set of duplicates has been deposited in the Lae Herbarium (PNG) and another in the University of Malaya Herbarium (KLU). Some of the collections are of considerable botanical interest, representing hitherto little-known species. One collection represents a new edible-nut species. The following list contains the botanical identifications, collection data, and some taxonomic comments. All the collections were made in June 1981. The Ok Tedi region is located around 5°12’S, 141°17’E.  相似文献   

12.
Translationally controlled tumor protein (TCTP) is an important immune regulator that has been implicated in a number of cellular processes, including cell growth, cell cycle progression, apoptosis regulation and protection of cells against various environmental stresses. In this study, we cloned and characterised TCTP from rock bream (Oplegnathus fasciatus), which is an economically important species in the Korean aquaculture industry. The full-length rock bream TCTP (RbTCTP) cDNA was of 1,041 bp and contained an open reading frame of 513 bp, which encoded 170 amino acids. The 5′ untranslated region (UTR) was 90 bp, while the 3′ UTR was 438 bp, containing a polyadenylation signal. RbTCTP showed 76, 75 and 74 % amino acid sequence identities to those of tilapia (Oreochromis niloticus), orange-spotted grouper (Epinephelus coioides) and Japanese sea perch (Lateolabrax japonicus), respectively. The positions of microtubule binding region, Ca+ binding region and TCTP signature regions in RbTCTP were similar to other fish species and mammals. RbTCTP mRNA expression level was highest in the gill compared to other tissues. The level of RbTCTP mRNA expression was significantly regulated by injection of red seabream iridovirus, Streptococcus iniae and Edwardsiella tarda.  相似文献   

13.
Three new species of the sciaenid genusAtrobucca are described:A. kyushini from off Borneo, differs from all known congeners in having no swimbladder appendages enveloplng the bladder, no forward directed branches from the ventral limbs of the appendages, a long tube-like last appendage parallel to the bladder wall and a pale mouth lining;A. brevis from off northern Australia and Papua New Guinea, is distinguished by its short pectoral fin (less than 23% SL) and pleural rib on the 11th vertebra;A. adusta from Papua New Guinea, is distinctive in having a low dorsal soft ray number (23–24) and long caudal peduncle (27–30% SL).Atrobucca Chu, Lo et Wu is redefined to accommodate the new species: the genus is principally characterized by the swimbladder appendages divided into developed dorsal and ventral limbs, and the only slightly curved sulcus tail of the sagitta. A key and diagnoses are provided for all known species ofAtrobucca.  相似文献   

14.
P-proteins are structural phloem proteins discussed to be involved in the rapid sealing of injured sieve elements. P-proteins are found in all dicotyledonous and some monocotyledonous plants, but additional crystalloid P-proteins, known as forisomes, have evolved solely in the Fabaceae. Both types are encoded by members of the sieve element occlusion (SEO) gene family, which comprises seven phylogenetic subgroups. The Fabaceae-specific subgroup 1 contains genes encoding forisome subunits in e.g. Medicago truncatula, Vicia faba, Dipteryx panamensis and Canavalia gladiata whereas basal subgroup 5 encodes P-proteins in Nicotiana tabacum (tobacco) and Arabidopsis thaliana. The function of remaining subgroups is still unknown. We chose Glycine max (soybean) as a model to investigate SEO proteins representing different subgroups in one species. We isolated native P-proteins to determine the SEO protein composition and analyzed the expression pattern, localization and structure of the G. max SEO proteins representing five of the subgroups. We found that subgroup 1 GmSEO genes encode forisome subunits, a member of subgroup 5 encodes a non-forisome P-protein and subgroup 2 GmSEO genes encode the components of forisome tails, which are present in a restricted selection of Fabaceaen species. We therefore present the first molecular characterization of a Fabaceae non-forisome P-protein and the first evidence that forisome tails are encoded by a phylogenetically-distinct branch of the SEO gene family.  相似文献   

15.
Five Torulopsis species, in which, characteristically, the mean molar percentage of guanine plus cytosine of the DNA bases (GC content) is above 50%, were examined to determine their cell-wall structure; the mode of bud formation; course of mitosis and their urease activity. The two urease-negative species, T. gropengiesseri (% GC 57.1) and T. silvatica (% GC 56.3), were found to possess affinitive properties which characterize perfect ascomycetous yeast species. In the urease-positive species, T. fujisanensis (% GC 65.0–66.1), T. ingeniosa (% GC 55.6) and T. philyla (% GC 63.9), there appeared to be a correlation between pronounced urease activity and the affinitive properties which characterize perfect basidiomycetous yeast species. Pronounced urease activity has, however, also been found in the ascomycetous species Schizosaccharomyces pombe. Consequently neither high GC ratios nor the presence of urease activity when considered individually, can be taken as reliable criteria when attempting to establish the affinity of yeasts the perfect states of which are not known, with the Basidiomycetes. A strain of the ascomycetous species Sclerotinia trifoliorum was examined by electron microscopy for comparative purposes.  相似文献   

16.
The following rodents and marsupials from the Western Highlands of Papua New Guinea have been examined for helminths: Anisomys imitator, Melomys spp., Pogonomelomys ruemmleri, Rattus spp., Echymipera kalubu and Peroryctes raffrayanus. Two new species and a number of new host records are reported. Echinostoma echymiperae n. sp., a digenean from the intestine of Echymipera kalubu, is characterised by the number of collar spines, the body armature and the shape and position of the gonads. Vampirolepis peroryctis n. sp., a cestode from the intestine of Peroryctes raffrayanus, is characterised by the length of the rostellar hooks, the shape of the ovary, the arrangement of the testes in a triangle and the extent of the cirrus-sac. Hymenolepis aklei, H. bradleyi, H. antechini, H. bettongiae, H. cercarteti, H. isoodontis and H. potoroi are transferred to Vampirolepis as new combinations. E. kalubu is a new host for Linstowia semoni and Pogonomelomys ruemmleri is a new host for Hymenolepis diminuta. V. peroryctis is the first platyhelminth to be reported from Peroryctes raffrayanus and Raillietina (Raillietina) sp. the second to be reported from the genus Melomys.  相似文献   

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Two new genera of Chrysobalanaceae are described.Hunga distributed in New Caledonia, the Loyalty Islands and Papua and New Guinea, contains eight species, three new, and five formerly placed in the generaAngelesia, Licania andParinari.Kostermanthus is described to accommodate two species with united filaments formerly placed inParinari andAcioa. Both new genera are quite as distinct as others of the family and have been overlooked by undue emphasis placed on the single character of a bilocular ovary.Licania palawanensis Prance is also described; it is the second species of its genus from Malesia.  相似文献   

20.
On the basis of the material collected in Morocco, Algeria, Tunisia, Lebanon, Syria and Turkey, and published data, mainly on Israel and Egypt, we try to establish a synthesis of the geographical distribution of the poorly known fauna of the South and Eastern Mediterranean basin. A first analysis shows that the fauna of this region is characterized by a high number of species with a widespread distribution (cosmopolite, holarctic, palaearctic ...) and therefore, with great affinities with the European fauna. Nevertheless, three distinct communities can be distinguished:

  • - The south western basin (North Africa; Morocco, Algeria, Tunisia), where the community is very poor, and which shows great affinities with south European, but none with the Ethiopian region;
  • - The south eastern basin (Egypt), with some species of African origin;
  • - The eastern basin (Near East, mainly Lebanon and Israel) with a very diversified community, partly due to its geographical situation, and partly due to a more intensive collecting pressure. This community includes a group of species with more eastern affinities (East Siberian ...), but none typically Ethiopian or exclusively Sino-Indian.
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