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1.
Two new species of Angiostoma Dujardin, 1845 taken from the intestines of terrestrial molluscs (Gastropoda: Stylommatophora) collected in the UK are described and illustrated. Angiostoma milacis n. sp. is parasitic in milacid and agriolimacid slugs and is closely related to A. asamati Spiridonov, 1985. Angiostoma zonitidis n. sp. was found in a zonitid snail and is most closely related to A. kimmeriense Korol & Spiridonov, 1992 (emend.), a species also from zonitid snails. An amended generic diagnosis is proposed. The distribution of A. limacis and A. milacis sp. n. in hosts is discussed and a key to the species of Angiostoma is presented.  相似文献   

2.
Angiostoma norvegicum n. sp. (Angiostomatidae) is described from the oesophagus, crop and the buccal mass of five species of slugs of the family Arionidae, Arion vulgaris (Moquin-Tandon), Arion ater (L.), Arion fasciatus (Nilsson), Arion fuscus (Müller) and Arion rufus/Arion ater hybrid), collected throughout Norway. Angiostoma norvegicum n. sp. was found parasitising arionids at seven of the 30 sample sites examined (23.3%), and 9.9% of all Arion spp. were infected with this nematode. The new species is characterised by its large size (4.0–8.6 mm long) and in having: lateral alae; 6 + 6 papillae at the cephalic end; a large circular mouth aperture; a spacious stoma; a pharyngeal basal bulb without valvular apparatus; an excretory pore near the base of bulb; a distal part of posterior ovary always outstretched; an anterior ovary distally nearly always outstretched; a vulva situated anterior to mid-body; long, nearly straight spicules and a small gubernaculum; three circumcloacal papillae and caudal genital papillae (GP) arranged in a pattern 1+2/3+3 with GP 5 and GP 8 opened on dorsal side of narrow bursa not reaching tail tip; short conical tails in both sexes with tips supplied by 4 short, unequal denticles. Morphologically, A. norvegicum n. sp. is similar to Angiostoma limacis Dujardin, 1845, which diagnostic characteristics are given based on examination of specimens from Norway and the UK. Conversely, the phylogenetic analyses based on D2D3 large subunit (LSU) rRNA gene sequences performed in the present study did not support the morphological affinity of these two species. Phylogenetic analyses demonstrated that although Angiostoma spp. cluster together, A. norvegicum n. sp. forms a tight monophyletic clade with the milacid nematode parasites Angiostoma margaretae Ross, Malan & Ivanova, 2011 and Angiostoma milacis Ivanova & Wilson, 2009.  相似文献   

3.
The feeding behaviour of the shelled sacoglossan Oxynoe olivacea was investigated to better understand the role and importance of this species in influencing encroachments of the alien alga Caulerpa taxifolia in the Mediterranean sea. We tested whether this slug preferred, as preliminary field observations suggested, an aggregative feeding behaviour and which part of the algal thallus, phylloid vs rhizoid, it preferred. Results showed that O. olivacea fed in groups and actively selected phylloid. This outcome poses important questions regarding the possibility that this species, fragmenting the alga thallus, could enhance dispersion and regeneration of C. taxifolia.  相似文献   

4.
A new species of Litomosoides Chandler, 1931 was collected from the abdominal cavity of Oxymycterus nasutus Waterhouse (Rodentia: Cricetidae) in the grassland of the Departamento Rocha, Uruguay. Litomosoides nasuti n. sp. belongs to the ‘sigmodontis group’, and is characterised by: salient amphids; two ventral and one dorsal labial papillae, but no cephalic papillae; a buccal capsule with a transparent anterior segment and an annular asymmetrical thickening; a muscular oesophagus; a bottle-shaped buccal cavity; the male with symmetrically situated cloacal papillae (one pair ad-cloacal and three pairs post-cloacal); phasmids displaced laterally to the longitudinal axis; and microfilariae without terminal nuclei in the tail tip. It resembles five known species; three of which have been recovered from Oxymycterus spp. in neighbouring countries. However, the new species can be differentiated from L. sigmodontis Chandler, 1931 by the shape and size of the buccal capsule; from L. navonae Notarnicola, 2005 by the muscular oesophagus; from L. legerae Bain, Petit & Berteaux, 1980 by the length of the oesophagus and the cephalic papillae; from L. anguyai Notarnicola, Bain & Navone, 2002 by the absence of lappets in the female tail; and from L. oxymycteri Notarnicola, Bain & Navone, 2000 by absence of pre-cloacal papillae. L. legerae from O. quaestor and L. sigmodontis from Sigmodon hispidus in North America are closely related species, as indicated by Brant & Gardner’s phylogenetic tree based on morphological characters. However, a new analysis is needed to include the recently described Argentinean species for a better understanding of the diversification of this genus.  相似文献   

5.
Summary  A new species of Macroptilium sect. Microcochle (Benth.) J. A. Lackey is herein described from the states of Piauí and Bahia, Brazil. Macroptilium cochleatum is characterized by few-flowered inflorescences, calyx teeth longer than the tube, a tightly four-coiled keel, and linear, patent fruits. The discovery of this unique Macroptilium species, with its distally coiled keel, expands the diagnostic features of the genus. A key to the Brazilian species of sect. Microcochle is provided.  相似文献   

6.
7.
Two northwestern Pacific species of the munnopsid subfamily Eurycopinae, Eurycope pavlenkoi Gurjanova, 1933 and E. ochotensis Kussakin, 1979 are transferred to the other genus of the subfamily, Baeonectes Wilson, 1982, on the basis of the following characteristics: short truncated epipod of maxilliped, broad rostrum without distinct margins, absence of a distomedial lobe of the article 1 of antenna 1, mandible with broad, rounded molar and long condyle and pereonites 5–7 fused dorsomedially. Based on the mentioned characters E. pygmaea G.O. Sars, 1870, which was put into the genus Tytthocope Wilson & Hessler, 1981 is also suggested to be transferred into the genus Baeonectes. After the clarification of the taxonomical position of the species, the geographical range of the genus Baeonectes expanded. In the Sea of Japan the genus was registered for the first time.  相似文献   

8.
The first record of Ornithodoros (Alectorobius) coniceps (Canestrini) was reported for Italy in 1877, inside the interstices of the ancient mosaics at S. Marco Basilica in Venice. Afterwards only few discoveries of the species are reported for Italy; the last record is dated back to 1984, in L’Aquila town (Abruzzo Region). The present study shows the data of a survey carried out as a result of a massive infestation by O. coniceps in an ancient villa in Anzio town (Latium region) recently restored. In the past decades the villa has been fallen into disrepair, becoming an occasional shelter for wild animals mainly pigeons, that colonized the whole building for generations. This case appears worthy of note because it is the first record of this species after more than 25 years in Italy. A total of 136 specimens were collected by three methods: manual, mechanical aspirators and Wilson traps. Wilson trapping indicates positive O. coniceps tropism for CO2.  相似文献   

9.
Sphaerellothecium stereocaulorum sp. nov., Stigmidium beringicum sp. nov., Stigmidium stereocaulorum sp. nov. and goniocysts are described on Stereocaulon species from the northern Holarctic. Endococcus nanellus is reported new to Alaska and Mongolia. Taxonomical novelties Sphaerellothecium stereocaulorum Zhurb. & Triebel, Stigmidium beringicum Zhurb. & Triebel, Stigmidium stereocaulorum Zhurb. & Triebel.  相似文献   

10.
R-spondin1 (RSPO1) is a potential female-determining gene in human (Homo sapiens) and mouse (Mus musculus). Its differential expression in these mammals is correlated with signaling for sex determination. As a way of studying sex determination in fish we cloned and analyzed a RSPO1 gene in zebrafish (Danio rerio). Using real-time PCR, we observed that RSPO1 is expressed more strongly in ovaries than in testes, suggesting that RSPO1 may have a role in gonad differentiation. High RSPO1 expression was detected in some non-gonadal organs like muscle and kidneys. In situ hybridization results demonstrate that RSPO1 is expressed in premature germ cells, in oogonia and primary oocytes in ovaries and in spermatogonia and spermatocytes in testes. It is also expressed in gonad somatic cells during gonadal development: in granulosa cells and theca cells of early and late cortical-alveolar stage follicles in ovaries, and in Leydig cells in testes. This differential expression may indicate that RSPO1 has a role(s) in zebrafish gonad development and differentiation. By fusing zebrafish RSPO1 with a green fluorescent protein gene, we found that RSPO1 is located in the cytosol and Golgi apparatus but not the nucleus of fish epithelioma papulosum cyprinid (EPC) cells. These preliminary findings suggest some aspects of RSPO1 like differential expression linked to sex determination may be conserved in fish while other aspects like subcellular localization differ from the mammalian RSPO1.  相似文献   

11.
Summary  Seven new names at species rank are proposed in Memecylon sect. Afzeliana Jacq.-Fél., a group of forest shrubs and small trees confined to Guineo-Congolian Africa. The group is centred in Cameroon, where 17 of the 20 species occur. A new flower type, the “star-flower” in Memecylon is revealed, and its taxonomic and ecological importance discussed. Three new, locally endemic species from the South West Province of Cameroon are described, mapped and illustrated: M. kupeanum R. D. Stone, Ghogue & Cheek, M. bakossiense R. D. Stone, Ghogue & Cheek, and M. rheophyticum R. D. Stone, Ghogue & Cheek. Two new names, M. accedens R. D. Stone, Ghogue & Cheek and M. hyleastrum R. D. Stone & Ghogue and one new combination, M. mamfeanum (Jacq.-Fél.) R. D. Stone, Ghogue & Cheek are provided at species level for three taxa originally proposed as varieties of M. afzelii G. Don. The taxon M. arcuatomarginatum var. simulans Jacq.-Fél. is also elevated to species status, as M. simulans (Jacq.-Fél.) R. D. Stone & Ghogue. Conservation assessments are provided for all the newly named taxa. A key is provided to the species of Memecylon sect. Afzeliana.  相似文献   

12.
Powdery mildew is an important foliar disease in wheat, especially in areas with a cool or maritime climate. A dominant powdery mildew resistance gene transferred to the hexaploid germplasm line NC99BGTAG11 from T. timopheevii subsp. armeniacum was mapped distally on the long arm of chromosome 7A. Differential reactions were observed between the resistance gene in NC99BGTAG11 and the alleles of the Pm1 locus that is also located on chromosome arm 7AL. Observed segregation in F2:3 lines from the cross NC99BGTAG11 × Axminster (Pm1a) demonstrate that germplasm line NC99BGTAG11 carries a novel powdery mildew resistance gene, which is now designated as Pm37. This new gene is highly effective against all powdery mildew isolates tested so far. Analyses of the population with molecular markers indicate that Pm37 is located 16 cM proximal to the Pm1 complex. Simple sequence repeat (SSR) markers Xgwm332 and Xwmc790 were located 0.5 cM proximal and distal, respectively, to Pm37. In order to identify new markers in the region, wheat expressed sequence tags (ESTs) located in the distal 10% of 7AL that were orthologous to sequences from chromosome 6 of rice were targeted. The two new EST-derived STS markers were located distal to Pm37 and one marker was closely linked to the Pm1a region. These new markers can be used in marker-assisted selection schemes to develop wheat cultivars with pyramids of powdery mildew resistance genes, including combinations of Pm37 in coupling linkage with alleles of the Pm1 locus.  相似文献   

13.
Members of the Coxiella genus are intracellular bacteria that can infect a variety of animals including humans. A symbiotic Coxiella was recently described in Amblyomma americanum ticks in the Northern Hemisphere with no further investigations of other Amblyomma species in other geographic regions. These ixodid ticks represent a group of important vectors for human infectious agents. In the present work, we have demonstrated that symbiotic Coxiella (SCox) are widespread, occurring in South America and infecting 100% of all life stages and eggs of the Cayenne ticks Amblyomma cajennense from Brazil and the USA. Using light microscopy, in situ hybridization, and PCR, we demonstrated SCox in salivary glands, ovaries, and the intestines of A. cajennense. These symbionts are vertically and transtadially transmitted in laboratory reared A. cajennense, and quantitative PCR analyses indicate that SCox are more abundant in adult female ticks, reaching values corresponding to an 11×, 38×, and 200× increase in SCox 16S rRNA gene copy number in unfed females, compared to unfed nymphs, larvae, and eggs, respectively. Phylogenetic analyses showed distinct SCox subpopulations in the USA and Brazil and demonstrated that SCox bacteria do not group with pathogenic Coxiella burnetii.  相似文献   

14.
Summary   Erythroxylum longisetulosum I. Loiola & M. F. Sales and E. timothei I. Loiola & M. F. Sales (sect. Rhabdophyllum) from north-eastern Brazil are described and illustrated, and their taxonomic and ecological relationships are discussed.  相似文献   

15.
The morphogenesis of fungiform papillae occurs in a stereotyped pattern on the dorsal surface of the mammalian tongue via epithelial–mesenchymal interactions. These interactions are thought to be achieved via intercellular communication. Gap junctions can be observed in many developing tissues and have been suggested to participate in a variety of functions, including the regulation of cell proliferation, differentiation, and apoptosis. Here, we demonstrate that the expression of Connexin 43 (Cx43), a gap junction protein, is correlated significantly with the development of fungiform papillae, which exhibit a pattern formation and morphogenesis similar to the development of other epithelial appendages. Antisense-oligodeoxynucleotide (AS-ODN) against Cx43 was used to assess the developmental functions of Cx43. The expression patterns of the signaling molecules were disrupted by Cx43 inhibition. Interestingly, the expression patterns of Shh, a key molecule in the determination of the spacing patterns of fungiform papillae, were disturbed after treatment with Cx43 AS-ODN. We have also attempted to determine the functions of Bmp-2 by applying NOGGIN protein to tongue cultures. Our results indicate that upstream regulation via Cx43 controls the Shh and Bmp-2 pathways for the morphogenesis and pattern formation of fungiform papillae.This work was supported by grant no. R01-2003-000-11649 from the Korea Science and Engineering Foundation.  相似文献   

16.
Fourteen new species of palms (Arecaceae) from Madagascar are described and named, based on material collected over the last 15 years. Twelve species belong to the genus Dypsis, namely D. andilamenensis Rakotoarin. & J. Dransf., D. anjae Rakotoarin. & J. Dransf., D. betsimisarakae Rakotoarin. & J. Dransf., D. culminis Rakotoarin. & J. Dransf., D. dracaenoides Rakotoarin. & J. Dransf., D. gautieri Rakotoarin. & J. Dransf., D. gronophyllum Rakotoarin. & J. Dransf., D. jeremiei Rakotoarin. & J. Dransf., D. metallica Rakotoarin. & J. Dransf., D. reflexa Rakotoarin. & J. Dransf., D. sancta Rakotoarin. & J. Dransf. and D. vonitrandambo Rakotoarin. & J. Dransf. and two species belong to the genus Ravenea: R. beentjei Rakotoarin. & J. Dransf. and R. hypoleuca Rakotoarin. & J. Dransf. Despite the fact that most of these species have been recorded from protected areas that are difficult to access in the eastern region of Madagasacar, they are all threatened. Based on IUCN categories and criteria, seven are Critically Endangered and seven are Vulnerable.  相似文献   

17.
The Ganitrus group of Elaeocarpus L. (incl. Elaeocarpus Sect. Ptilanthus Schltr.) as found in Malesia is examined and some understanding reached. The group is more complex and speciose in eastern Malesia, especially in Papuasia (with the Philippines, Sulawesi and Maluku somewhat less rich) than in western and central Malesia. E. angustifolius Blume (syn. E. ganitrus & E. sphaericus auctt. mult.) — the source of the ornamental beads known as rudraksha of eastern commerce, from which malas or rosaries are made — is considered to be very variable in Malesia and probably varies further in the extremes of its range; outside Malesia the Ganitrus group is represented by ‘E. angustifolius s.l.’ only. The following species are recognised: E. altisectus Schltr. with a new subsp. carrii Coode from New Guinea; E. angustifolius Blume; E. avium Coode sp. nov. from New Guinea; E. buderi Coode; E. dolichostylus Schltr. with E. chloranthus treated as var. chloranthus (A. C. Sm.) Coode from New Guinea, with a new var. elliptifolius Coode from the Talaud/Sangihe Is. and a new var. hentyi Coode (replacing and re-interpreting subsp. collinus Coode) from New Guinea; E. fulvus Elmer; E. kaniensis Schltr.; E. ornatus Coode sp. nov. from New Guinea; E. osiae Coode sp. nov. from Bougainville I.; E. ptilanthus Schltr.; E. ramiflorus Merr. and E. trichopetalus Merr. & Quisumb. — a total of 12 species although the last two are perhaps not truly distinct from E. angustifolius. The stone sculpturing is discussed and some useful characters revealed. Attention is drawn to a collection from mid-altitude in Papua New Guinea, inadequately known but probably a new species in this group.  相似文献   

18.
19.
We report the first systematic survey for the presence of Wolbachia endosymbionts in aphids and whiteflies, particularly different populations and biotypes of Bemisia tabaci. Additional agriculturally important species included were predator species, leafhoppers, and lepidopterans. We used a polymerase chain reaction (PCR)-based detection assay with ribosomal 16S rDNA and Wolbachia cell surface protein (wsp) gene primers. Wolbachia were detected in a number of whitefly populations and species, whitefly predators, and one leafhopper species; however, none of the aphid species tested were found infected. Single, double, and triple infections were detected in some of the B. tabaci populations. PCR and phylogenetic analysis of wsp gene sequences indicated that all Wolbachia strains found belong to group B. Topologies of the optimal tree derived by maximum likelihood (ML) and a ML tree in which Wolbachia sequences from B. tabaci are constrained to be monophyletic are significantly different. Our results indicate that there have been at least four independent Wolbachia infection events in B. tabaci. The importance of the presence of Wolbachia infections in B. tabaci is discussed. RID= ID= <E5>Correspondence to: </E5>K. Bourtzis; <E5>email:</E5> kbourtz&commat;cc.uoi.gr Received: 9 September 2002 / Accepted: 25 September 2002  相似文献   

20.
The Bacteroides genus, the most prevalent anaerobic bacteria of the intestinal tract, carries a plethora of the mobile elements, such as plasmids and conjugative and mobilizable transposons, which are probably responsible for the spreading of resistance genes. Production of β-lactamases is the most important resistance mechanism including cephalosporin resistance to β-lactam agents in species of the Bacteroides fragilis group. In our previous study, the cfxA gene was detected in B. distasonis species, which encodes a clinically significant broad-spectrum β-lactamase responsible for widespread resistance to cefoxitin and other β-lactams. Such gene has been associated with the mobilizable transposon Tn4555. Therefore, the aim of this study was to detect the association between the cfxA gene and the presence of transposon Tn4555 in 53 Bacteroides strains isolated in Rio de Janeiro, Brazil, by PCR assay. The cfxA gene was detected in 11 strains and the Tn4555 in 15. The transposon sequence revealed similarities of approximately 96% with the B. vulgatus sequence which has been deposited in GenBank. Hybridization assay was performed in attempt to detect the cfxA gene in the transposon. It was possible to associate the cfxA gene in 11 of 15 strains that harbored Tn4555. Among such strains, 9 presented the cfxA gene as well as Tn4555, but in 2 strains the cfxA gene was not detected by PCR assay. Our results confirm the involvement of Tn4555 in spreading the cfxA gene in Bacteroides species.  相似文献   

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