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1.
Mussaenda yunnanensis, a new dioecious species of Rubiaceae from Yunnan Province, China, is described and illustrated. The new species can be recognized by its slender stem, congested‐cymose inflorescences and long corolla tubes. Differences between M. yunnanensis and two morphologically similar species (M. pubescens and M. antiloga) are presented. We also provide a key to all dioecious species of Mussaenda in China. The delimitation of the new species is further supported by molecular phylogenetic analyses based on eight plastid loci.  相似文献   

2.
In an investigation of Pythium species in China, two new species, P. agreste and P. wuhanense, were identified based on morphological characteristics and DNA sequence data. Pythium agreste has slightly inflated sporangia, oogonia encompassed by antheridia and antheridial stalks forming a very complicated knot, and plerotic oospores. It differs from the morphologically similar P. volutum which has inflated sporangia, bigger oogonia, and aplerotic oospores; from P. kashmirense which has contiguous inflated sporangia, catenulate oogonia and coiled or bent oogonial stalks; and from P. pectinolyticum which has catenulate oogonia and bigger oogonia and oospores. Pythium wuhanense can be differentiated from morphologically similar P. emineosum and P. paroecandrum by its possession of intercalary cylindrical to elongated sporangia and intercalary oogonia catenulate with sporangia and antheridia. Phylogenetic analyses showed that these two new species were clearly separated from morphologically similar Pythium species, based on the internal transcribed spacer (ITS) region and cytochrome C oxidase subunit I (COI) gene sequences using maximum parsimony and Bayesian methods. The two new species are described and illustrated in detail.  相似文献   

3.
In an investigation of Pythium species in lawn grassland of south China, two new species, Pythium breve and P. baisense, were identified based on morphological characteristics and DNA sequence data. These two new species differ morphologically from the other Pythium species by the oogonia encompassed by many antheridia and with 1?C3 antheridia on the wavy and curved stalks. Furthermore, P. baisense with complexly lobed antheridial stalks differs from P. breve with antheridial stalks entwining the hyphae nearby the oogonia with several turns. Results of phylogenetic analyses showed that these two new species were clearly separated from morphologically similar Pythium species based on the internal transcribed spacer region (ITS1, 5.8S, ITS2) and cytochrome c oxidase subunit I (COXI) gene sequences using maximum parsimony and Bayesian methods. These two new species are described and illustrated in detail.  相似文献   

4.
5.
A new polypore species, Antrodia hyalina, is described from Russia. It is morphologically similar to Antrodia pulvinascens, but differs in having annual, thinner and softer basidiocarps, solid skeletal hyphae, and cylindrical spores. Antrodia leucaena, originally described from China, is reported as new from Finland and Russia on Populus tremula. Antrodia wangii is regarded as a synonym of A. bondartsevae.  相似文献   

6.
New murids of Late Miocene (medial Baodean Chinese Mammal Unit) age from Inner Mongolia, northern China, and from Yunnan Province, southern China, are described. Hansdebruijnia perpusilla nov. sp. represents the earliest known and morphologically most primitive species of the genus, which is known from the latest Miocene of Europe and western Asia. The new species suggests an eastern Palaearctic origin of Hansdebruijnia. “ProgonomysyunnanensisQIU and STORCH, 1990 from Lufeng, Yunnan Province, is referred to Linomys nov. gen. New samples from Leilao, Yuanmou County, Yunnan Province, are included in this species, although this population is somewhat more primitive than that from Lufeng. Leilaomys zhudingi nov. gen. and sp. from Leilao shows a unique combination of apomorphic and plesiomorphic characters, which suggest an early divergence from the murid stem. The new findings indicate that our knowledge of the early radiation of murids in southeast Asia is still in its infancy.  相似文献   

7.
Ossicaulis is a small genus in the family Lyophyllaceae. Two known species, O. lachnopus, and O. lignatilis, are distributed in north temperate regions. The third taxon, O. yunnanensis sp. nov., is described from the alpine belt of subtropics of southwestern China, and this genus is also reported for the first time from China. Morphologically, the new species is characterized by its whitish basidiomata and very small basidiospores. Molecular analyses from the nuclear rDNA internal transcribed spacer region (ITS) show that the subtropical alpine species is distinct from hitherto known Ossicaulis species and has a close relationship to O. lachnopus.  相似文献   

8.
Evidence from molecular genetics demonstrates that Pinus densata is a natural homoploid hybrid originating from the parent species Pinus tabuliformis and Pinus yunnanensis, and ecological selection may have played a role in the speciation of P. densata. However, data on differentiation in adaptive traits in the species complex are scarce. In this study, we performed a common garden test on 16 seedling traits to examine the differences between P. densata and its parental species in a high altitude environment. We found that among the 16 analyzed traits, 15 were significantly different among the species. Pinus tabuliformis had much earlier bud set and a relatively higher bud set ratio but poorer seedling growth, and P. yunnanensis had opposite responses for the same traits. P. densata had the greatest fitness with higher viability and growth rates than the parents. The relatively high genetic contribution of seedling traits among populations suggested that within each species the evolutionary background is complex. The correlations between the seedling traits of a population within a species and the environmental factors indicated different impacts of the environment on species evolution. The winter temperature is among the most important climate factors that affected the fitness of the three pine species. Our investigation provides empirical evidence on adaptive differentiation among this pine species complex at seedling stages.  相似文献   

9.
We describe a new nematode species, Baylisascaris potosis n. sp., isolated from captive kinkajou, Potos flavus, from the Cooperative Republic of Guyana. The nematode was found in fecal specimens, identified morphologically, and confirmed genetically. The new species is similar to Baylisascaris procyonis, Baylisascaris columnaris, and other Baylisascaris species, but is distinguished by the position of the male phasmidial pole. Nuclear and mitochondrial DNA sequence analyses confirmed that the new species is phylogenetically distinct from all the members of the genus Baylisascaris, and groups with B. procyonis and B. columnaris. This nematode is the 10th species assigned to the genus Baylisascaris.  相似文献   

10.
A new species of Primulaceae, Primula undulifolia, is described from the hilly area of Hunan province in south-central China. Its morphology and distributional range suggest that it is allied to P. kwangtungensis, both adapted to subtropical climate, having contiguous distribution and similar habitat, growing on shady and moist cliffs. Petioles, scapes and pedicels of them are densely covered with rusty multicellular hairs, but the new species can be easily distinguished by its smaller flowers and narrowly oblong leaves with undulate margins. Molecular phylogenetic analysis based on four DNA markers (ITS, matK, trnL-F and rps16) confirmed the new species as an independent lineage and constitutes a main clade together with P. kwangtungensis, P. kweichouensis, P. wangii and P. hunanensis of Primula sect. Carolinella.  相似文献   

11.
Anguina plantaginis n. sp., parasitic on Plantago aristata, is described and illustrated. This new species is most closely related to A. klebahni, A. millefolii, A. mobilis, and A. moxae and is characterized as follows: moderate body size for the genus; absence of esophageal "storage organ"; postvulval uterine sac extending about 45% of vulva-anus distance; crustaformeria of young females longer than spermatotheca or uterus proper; spicules with 2 sclerotized thickenings; long, conical tail in both sexes, narrowing at about 1/6 of its length to peg-like tip; parasitic only on P. aristata. Two nematode generations that are morphologically similar but differ in body size develop in one plant gall. The postembryogenesis, studied with respect to morphological development of the larval stages, is similar to that of Ditylenchus. The sexes can be differentiated from the second molt on. The infective larva is the third stage, which is morphologically distinct from the regularly developing third-stage larva.  相似文献   

12.
《Mycoscience》2014,55(5):390-399
Based on morphological characteristics and molecular phylogeny, a rust fungus on Salix hsinganica, S. sinica, S. starkeana, S. wallichiana and S. xerophila in China is described as a new species, Melampsora salicis-sinicae. This new species morphologically resembles M. capraearum and M. epiphylla in having subcuticular teliospores with a thickened apical wall, but it differs from these two species in its amphigenous telia. In addition, this new species differs from M. capraearum in its slender teliospores and thinner apical thickness of teliospores, and it also differs from M. epiphylla in the dimension of urediniospores, the position of teliospores and the apical thickness of teliospores. Phylogenetic analyses using partial sequences of the D1/D2 region of nuclear large subunit and the internal transcribed spacer (ITS1 and ITS2) regions including 5.8S of ribosomal RNA gene and the translation elongation factor 1 alpha (EF-1α) gene revealed that this rust fungus was distinct from its morphologically similar species, M. capraearum and M. epiphylla.  相似文献   

13.
Pestalotiopsis sp. is a mycoparasite of the plant pathogen Aecidium wenshanense. To further understand the mycoparasitism mechanism of Pestalotiopsis sp., we assembled and analyzed its genome. The genome of Pestalotiopsis sp. strain PG52 was assembled into 335 scaffolds and had a size of 58.01 Mb. A total of 20,023 predicted genes and proteins were annotated. This study compared PG52 with the mycoparasites Trichoderma harzianum, Trichoderma atroviride, and Trichoderma virens. This study reveals the entirely different mycoparasitism mechanism of Pestalotiopsis compared to Trichoderma and reveals this mycoparasite’s strong ability to produce secondary metabolites.  相似文献   

14.
The main aim of this study is to compare all taxa from the Pinus kesiya complex and related P. tabuliformis using statistical, ordination and discrimination techniques focusing on ten most discriminating morphological traits. Special emphasis was placed on the recently described taxa Pinus densata subsp. tibetica and P. × naxiorum (=P. yunnanensis × P. densata). Population comparisons of the particular main geographic distribution areas of Pinus kesiya, P. densata subsp. tibetica and P. yunnanensis were also conducted separately within each mentioned taxon using the same data. Pinus densata subsp. tibetica proved to be sufficiently morphologically differentiated from subsp. densata as well as from other species of the P. kesiya complex and P. tabuliformis. The recently originating hybrid P. × naxiorum appears to be intermediate between its parents. The unique shrubby taxon P. densata var. pygmaea is clearly closer to P. densata than to P. yunnanensis, to which it has been classified in Chinese floras. Populations of four distant Pinus kesiya geographic distribution areas lack substantial differences that would support the recognition of infraspecific taxa such as subsp. insularis or var. langbianensis. Pinus yunnanensis is very similar to P. kesiya, with only one trait, leaf length, being significantly different.  相似文献   

15.
16.
Platycladus Spach is native to Central China, but its natural occurrences are very difficult to establish. According to molecular phylogenetic data, this genus might have originated since the Oligocene, but no fossil record has been reported. Here, we describe eight foliage branches from the upper Miocene in western Yunnan, Southwest China as a new species, P. yunnanensis sp. nov., which is characterized by foliage branches spread in flattened sprays, and leaves decussate, imbricate, scale-like and dimorphic. The leaves are amphistomatic, and the stomata are elliptical or oblong, haplocheilic, and monocyclic type. Based on a detailed comparison with the extant genera of Cupressaceae sensu lato, our fossils are classified into the genus Platycladus. The occurrence of P. yunnanensis sp. nov. indicates that this genus had a more southernly natural distribution in the late Miocene than at present. Molecular phylogeny and fossil records support a pre-Oligocene common ancestor for the genera Platycladus, Microbiota and Calocedrus. The separation of the three taxa was most likely caused by the arid belt across Central China during the Oligocene. In addition, the cooling down of the global temperature and the strengthening of Asian monsoon since the Miocene will further promote the migration of these genera.  相似文献   

17.
《Mycoscience》2020,61(2):71-75
Aspergillus is a monophyletic genus comprising the subgenera Aspergillus, Circumdati, Cremei, Fumigati, Nidulantes and Polypaecilum. The subgenus Circumdati contains many economically important species and mycotoxin producers. Section Jani was recently introduced with morphological and molecular support. In the present study, two strains isolated from farmland soil were assigned in section Jani based on multi-locus phylogenetic analyses but showed low similarity with existing species. Further morphological observation found they had wider vesicles and conidia connections which were different from the known species. Based on phylogenetic and morphological data, Aspergillus yunnanensis was introduced as the third species in section Jani. Members in section Jani are rarely distributed, this is the first report of this section in China.  相似文献   

18.
Hybridization between distinct populations or species is increasingly recognized as an important process for generating biodiversity. However, the interaction between hybridization and speciation is complex, and the diverse evolutionary outcomes of hybridization are difficult to differentiate. Here we characterize potential hybridization in a species group of swallowtail butterflies using microsatellites, DNA sequences, and morphology, and assess whether adaptive introgression or homoploid hybrid speciation was the primary process leading to each putative hybrid lineage. Four geographically separated hybrid populations were identified in the Papilio machaon species group. One distinct mitochondrial DNA clade from P. machaon was fixed in three hybrid taxa (P. brevicauda, P. joanae, and P. m. kahli), while one hybrid swarm (P. zelicaon x machaon) exhibited this hybrid mtDNA clade as well as widespread parental mtDNA haplotypes from both parental species. Microsatellite markers and morphology showed variable admixture and intermediacy, ranging from signatures of prolonged differential introgression from the paternal species (P. polyxenes/P. zelicaon) to current gene flow with both parental species. Divergences of the hybrid lineages dated to early- to mid-Pleistocene, suggesting that repeated glaciations and subsequent range shifts of parental species, particularly P. machaon hudsonianus, facilitated initial hybridization. Although each lineage is distinct, P. joanae is the only taxon with sufficient evidence (ecological separation from parental species) to define it as a homoploid hybrid species. The repetition of hybridization in this group provides a valuable foundation for future research on hybridization, and these results emphasize the potential for hybridization to drive speciation in diverse ways.  相似文献   

19.
Melampsora nujiangensis, a rust fungus found on Populus yunnanensis in China, is described as a new species. Light and scanning electron microscopy with herbarium specimens of the rust fungus show that the shape of its urediniospores differs from that of other known species of Melampsora, and its urediniospore walls are thinner than the other species. Furthermore, in phylogenetic trees based on the DNA sequences (28S and ITS) the rust fungus is phylogenetically separated by high bootstrap values. These results indicate that the fungus is an isolated species among the genus Melampsora. Contribution no. 202 from the Laboratory of Plant Parasitic Mycology, Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan  相似文献   

20.
A new white truffle species, Tuber panzhihuanense from China   总被引:1,自引:0,他引:1  
A new white Tuber species, T. panzhihuanense, is described based on collections from Sichuan and Yunnan, China. This is one of 10 new white truffle species, which were discovered in 2010 and 2011. Morphological and molecular analysis shows that T. panzhihuanense is clearly different from any other taxon in the genus of Tuber. It grows in mycorrhizal association with trees of Pinus yunnanensis in limestone soils. It has a pleasant aroma and is good edible. This is the first white truffle species discovered in China that has commercial potential.  相似文献   

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