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2.
BackgroundSusceptibility of tsetse flies (Glossina spp.) to trypanosomes of both humans and animals has been associated with the presence of the endosymbiont Sodalis glossinidius. However, intrinsic biological characteristics of the flies and environmental factors can influence the presence of both S. glossinidius and the parasites. It thus remains unclear whether it is the S. glossinidius or other attributes of the flies that explains the apparent association. The objective of this study was to test whether the presence of Trypanosoma vivax, T. congolense and T. brucei are related to the presence of S. glossinidius in tsetse flies when other factors are accounted for: geographic location, species of Glossina, sex or age of the host flies. ResultsFlies (n = 1090) were trapped from four sites in the Shimba Hills and Nguruman regions in Kenya. Sex and species of tsetse (G. austeni, G. brevipalpis, G. longipennis and G. pallidipes) were determined based on external morphological characters and age was estimated by a wing fray score method. The presence of trypanosomes and S. glossinidius was detected using PCR targeting the internal transcribed spacer region 1 and the haemolysin gene, respectively. Sequencing was used to confirm species identification. Generalised Linear Models (GLMs) and Multiple Correspondence Analysis (MCA) were applied to investigate multivariable associations. The overall prevalence of trypanosomes was 42.1%, but GLMs revealed complex patterns of associations: the presence of S. glossinidius was associated with trypanosome presence but only in interactions with other factors and only in some species of trypanosomes. The strongest association was found for T. congolense, and no association was found for T. vivax. The MCA also suggested only a weak association between the presence of trypanosomes and S. glossinidius. Trypanosome-positive status showed strong associations with sex and age while S. glossinidius-positive status showed a strong association with geographic location and species of fly. ConclusionsWe suggest that previous conclusions about the presence of endosymbionts increasing probability of trypanosome presence in tsetse flies may have been confounded by other factors, such as community composition of the tsetse flies and the specific trypanosomes found in different regions. 相似文献
4.
Three new species of Selaginella are described from the Guayana Highland of Venezuela: S. cardiophylla, S. hemicardia and S. pruskiana. They are illustrated and the relationships of each are discussed. Another species, provisionally determined as S. terezoana, is reported for the first time from Guyana. 相似文献
6.
A preliminary list is given of the species of the Muscidae (Diptera) of the Magadan region, including 93 species in 23 genera. Eighty-one species are newly recorded from this territory. Six species [ Spilogona aenea Huckett, 1965, S. bifimbriata Huckett, 1965, S. fulvibasis Huckett, 1965, S. incerta Huckett, 1965, S. separata Huckett, 1965, S. trigonifera (Zetterstedt, 1838)] are newly recorded for Russia. All these species, except Spilogona trigonifera, are newly recorded for the Palaearctic region. The species list includes the material examined, ecological data of some species, the distribution and all known references to each species. According to preliminary estimates, this list reflects 60% of expected species in the Magadan region. Two new synonyms are proposed: Coenosia shumshuensis Shinonaga & Zhang, 2000, n. syn. for C. alaskensis Huckett, 1965, and Coenosia remissa Huckett, 1965, n. syn. for C. ciliata Hennig 1961. 相似文献
7.
Thirteen new species of the genus Stevia are described and illustrated from Mexico: S. chilapensis, S. coahuilensis, S. crassifolia, S. ecatepecana, S. filodecaballoana, S. mascotensis, S. mexicana, S. oaxacana,
S. oligophylla, S. potosina, S. rotundifolia, S. scabrelloides, and S. viejoana. In addition, two varieties, Stevia aschenborniana Sch. Bip. ex Klotzsch var. occidentalis Grashoff and S. palmeri A. Gray var. constricta Grashoff are herein redefined as being distinct species, S. occidentalis and S. constricta stat. nov. Stevia mexicana resembles Stevia trifida Lagasca but differs in the habit. 相似文献
8.
In preparation of a treatment of Swartzia (Leguminosae) for the Flora Mesoamericana, recent updates to the taxonomy of the genus in Central America are discussed,
and two new species from the Pacific slope and lowlands of central and southern Costa Rica are described and illustrated.
One of them, S. picramnioides, is a member of the section Possira and is closely related to S. standleyi of Guatemala and Belize and to the South American species S. myrtifolia. The other, S. zeledonensis, belongs to the Central American apetalous clade of section Terminales. It is probably most closely related to the Panamanian species, S. nuda. We conclude that Swartzia is represented in Mexico and Central America by 14 species and provide a key for their identification. 相似文献
9.
Symplocos pachycarpa is described as new, and an illustration is provided. This species grows in cloud forests and oak-pine forests of Oaxaca
and Guerrero, Mexico, and is most similar to S. citrea. A key is provided to distinguish S. pachycarpa from related Mexican species. 相似文献
10.
Sequences of the nuclear ribosomal internal transcribed spacer regions 1 & 2 (nrDNA ITS) including the intervening 5.8S region
were analyzed cladistically for 43 individuals of 35 species of Scaphyglottis s.l. plus two outgroup taxa. Low levels of sequence divergence do not allow estimation of relationships among most clades,
but the analyses indicate that four segregate genera ( Hexisea Lindl., Reichenbachanthus Barb. Rodr., Hexadesmia Brogn., and Platyglottis coriacea L.O. Williams) are embedded within a broad paraphyletic Scaphyglottis. This broadly defined Scaphyglottis sensu Dressler is characterized within Laeliinae by the usual presence of superposed growth habit and the presence of a column
foot. In order to accommodate species formerly placed in Platyglottis and Reichenbachanthus, three new combinations are made in Scaphyglottis: Scaphyglottis brasiliensis (Schltr.) Dressler, S. coriacea (L. O. Williams) Dressier, and S. emarginata (Garay) Dressler. 相似文献
11.
A taxonomic revision of the genus Aneorhachis Kleine 1923 (Coleoptera: Brentidae) and a phylogenetic analysis of species belonging to this genus are carried out. The genus Ipsopisthius Kabakov 2001 is synonymised with Aneorhachis, and two new combinations are proposed: Aneorhachis hirta (Kabakov 2001), n. comb. and A. incerta (Kleine 1935), n. comb. Higonius nitens Goossens 2008 is synonymized with A. incerta. One new species is described from New Guinea, A. papuana n. sp. All the species are redescribed and type-specimens are illustrated; an identification key is proposed. A maximum parsimony analysis is provided on the base of 23 characters from adult morphology. This analysis confirms the monophyly of the genus and seems to show that Aneorhachis originated on continental Asia and then spread out eastward to colonize Pacific islands. 相似文献
12.
Abstract A new species of nematode, Heth baudini sp. n. from a diplopod (Spirostreptida: Iulomorphidae Verhoeff, 1924) collected in Queensland, Australia, is described and illustrated. The cephalic and cervical cuticular ornamentation of females of H. baudini sp. n. is similar to those of South-East Asian and Australasian Heth species. Heth baudini sp. n. females are particularly close to Heth taynguyeni from Vietnam but can be distinguished by the shape of the lateral lappets, which in H. taynguyeni limit the trapezium-shaped region of smooth cuticle unlike the elliptical region in H. baudini sp. n., and by the presence of lateral spines only half the size. The cuticle of the H. baudini sp. n. is finely annulated along the entire body, whereas H. taynguyeni has broader rings behind the first pair of lateral spines, each consisting of five or six narrower rings separated from each other by deeper furrows. Males of H. baudini sp. n. are characterised by the presence of a bursa-like fold on the tail and can be distinguished from other species of the genus by the presence of somatic papillae embedded into the bursal fold. 相似文献
13.
Twelve morphologically similar species of Acrapex Hampson 1894, (Lepidoptera, Noctuidae, Noctuinae, Apameini, Sesamiina), from Western, Central and Eastern Africa are reviewed. Eight of these species are new to science and are described: Acrapex akunamatata n. sp. and A. incrassata n. sp. from Kenya; A. gracilis n. sp., A. iringa n. sp., A. lukumbura n. sp. and A. rungwe n. sp. from Tanzania; A. soyema n. sp. from Ethiopia; and A. zoutoi n. sp. from Benin. All 12 species belong to a species complex that we hereby define as the Acrapex apicestriata group. Host-plants for three of the new species are recorded: Setaria incrassata (Hochst.) Hack. for Acrapex incrassata; Cymbopogon pospishilii (K. Schum.) C.E. Hubb. for A. rungwe; and Andropogon perligulatus Stapf. for A. zoutoi. We also conducted molecular phylogenetic analyses (using maximum likelihood and Bayesian inference) on a six gene multimarker molecular dataset (four mitochondrial and two nuclear gene fragments; 4581 nucleotides in length) consisting of 15 Acrapex species (including seven species from the apicestriata group) and four outgroups species from the subtribe Sesamiina (from genera Busseola Thurau 1904, Sciomesa Tams & Bowden 1953, Pirateolea Moyal, Le Ru, Conlong, Cugala, Defabachew, Matama-Kauma, Pallangyo & Van den Berg 2010 and Sesamia Boisduval & Guenée 1852). Both maximum likelihood and Bayesian inference analyses yield a similar and well-supported topology, which supports the monophyly of the apicestriata group. 相似文献
14.
Background: It is argued that coastal endemic taxa may evolve in parallel at the periphery of the distributional range of a widespread species. Aims: We tested this hypothesis for the origins of three peripheral, coastal isolates of Senecio, S. glaucus ssp. glaucus (Israel), S. g. ssp. coronopifolius p.p. (Sicily), and S. hesperidium (Morocco), from widespread S. glaucus ssp. coronopifolius. We also determined the relative roles of selection vs. genetic drift in shaping phenotypic divergence in ssp. glaucus and S. hesperidium, using Lande’s test of neutral morphological change. Methods: We surveyed morphological and/or allozyme variation in the three peripheral isolates and mainly inland populations of S. g. ssp. coronopifolius.Results: Genetic data supported independent origins of the coastal taxa from nearby populations of ssp. coronopifolius. These descendant and ancestral populations showed pronounced morphological but weak genetic differentiation. Phenotypic similarities between ssp. glaucus (Israel) and S. hesperidium (Morocco) in plant height and floral traits may have resulted from parallel divergent selection from ssp. coronopifolius, though drift remains an alternative cause in S. hesperidium. Conclusions: Our results indicate parallel ecotype formation and (sub)speciation in Senecio in which primarily selective vs. neutral determinants promoted the recurrent origin of coastal types in, respectively, Israel and Morocco. 相似文献
15.
Nine new species of Solanum and two of Capsicum are described from Bolivia. Notes are provided on some other species, including the complex typification of Solanum aridum. Capsicum caballeroi, C. ceratocalyx, Solanum chalmersii, S. clandestinum, S. comarapanum, S. complectens, S. monanthemon,
S. moxosense, S. pedemontanum, S. saturatum, and S. whalenii are described and illustrated, and a new name, S. scuticum, is proposed for the species previously known as S. tabacifolium. 相似文献
16.
Background: The presence of exotic plants increases the heterospecific pollen (HP hereafter) received by native plants and reduces their reproductive output. Aims: We assessed whether the exotic herb Echium vulgare (Boraginaceae) increased HP and reduced seed output of the native plants Phacelia secunda (Boraginaceae) and Stachys albicaulis (Lamiaceae) in an Andean locality, central Chile. Methods: The presence of HP was studied in native plants growing with and without co-existence with the exotic E. vulgare. A complementary hand pollination experiment was carried out to assess whether E. vulgare pollen reduced the reproductive success of native plants. Results: In the presence of E. vulgare, 17.3% and 3.7% of P. secunda and S. albicaulis individuals that coexisted with the exotic species received HP. For P. secunda, the number of conspecific pollen grains decreased in invaded patches compared with non-invaded patches; no differences were observed for S. albicaulis. The pollen of E. vulgare negatively affected the reproductive success of S. albicaulis but not that of P. secunda. Conclusions: The presence of HP cannot be predicted from the presence of exotic plants alone, and other factors, such as flower morphology, could explain the greater HP transfer in P. secunda (actinomorphic flowers) than in S. albicaulis (zygomorphic flowers). A higher negative effect of E. vulgare pollen on P. secunda versus S. albicaulis could be related to the phylogenetic resemblance between the exotic donor and native recipient plant because pollen-stigma compatibility may be evolutionary conserved through common lineages. 相似文献
17.
A new species of Stephanopodium (Dichapetalaceae) from tabuleiro forests in southern Bahia is here described and illustrated. This species, named Stephanopodium gracile because of its slender habit, is compared to S. blanchetianum and S. organense. From these two species, S. gracile can be distinguished by the inflorescences on the apical portion of the leaf petiole, young branches with sparse short appressed
trichomes, and glabrous leaves; from S. blanchetianum it differs also by leaf blades with an acuminate (vs. usually obtuse or rounded, and sometimes acute) apex. 相似文献
18.
Abstract Desmids of the peat-bog of Vedes (Trento, North-Italy). A list of 27 Desmids s.l. (Desmidiaceae, Closteriaceae and Mesotaeniaceae) observed in some samples coming from the peat-bog of Vedes (Trento, North-Italy) is reported. This is a high moor bog situated at an altitude of 1496 m and rich in Sphagnum species (Sphagnum medium, S. fuscum, S. robustum, S. laricinum, etc.). The most interesting Desmids found are: Actinotaenium cucurbita, A. crassiusculum, Bambusina brebissonii, Penium polymorphum, Tetmemorus brebissonii, T. laevis, Closterium intermedium, Cosmarium amoenum, Euastrum insigne, Netrium digitus and Staurastrum erostellum, the last one being a very rare species found for the first time in Italy; thirteen entities are new for the algal flora of Trentino-Alto Adige. 相似文献
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