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1.
Singchia Z. J. Liu & L. J. Chen, a new orchid genus, is established based on the new species S. malipoensis Z. J. Liu & L. J. Chen found in southeast Yunnan, China. The new genus is related to Pteroceras, from which it differs by having a lip with its basal margins immovably adnate to the lower part of the pendent column foot, a thin-walled spur, and very unequally and deeply split pollinia, each with a distinct caudicle. In addition to a discussion on Ascocentrum pusillum, a species of questionable placement, another new genus, namely Gunnaria S. C. Chen ex Z. J. Liu & L. J. Chen, is set up and a new combination, namely G. pusilla (Aver.) Z. J. Liu & L. J. Chen, is made. The new genus Gunnaria differs from its allyAscocentrum by having a cross-shaped pollinarium, sulcate or split pollinia, each with a distinct caudicle attached to a common linear stipe much longer than either pollinia or viscidium, and strongly incurved side lobes of the lip.  相似文献   

2.
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.  相似文献   

3.
We conducted phylogenetic analyses using two DNA sequence data sets derived from matK, the maturase-coding gene located in an intron of the plastid gene trnK, and the internal transcribed spacer region of 18S–26S nuclear ribosomal DNA to examine relationships in subtribe Aeridinae (Orchidaceae). Specifically, we investigated (1) phylogenetic relationships among genera in the subtribe, (2) the congruence between previous classifications of the subtribe and the phylogenetic relationships inferred from the molecular data, and (3) evolutionary trends of taxonomically important characters of the subtribe, such as pollinia, a spurred lip, and a column foot. In all, 75 species representing 62 genera in subtribe Aeridinae were examined. Our analyses provided the following insights: (1) monophyly of subtribe Aeridinae was tentatively supported in which 14 subclades reflecting phylogenetic relationships can be recognized, (2) results are inconsistent with previous classifications of the subtribe, and (3) repeated evolution of previously emphasized characters such as pollinia number and apertures, length of spur, and column foot was confirmed. It was found that the inconsistencies are mainly caused by homoplasy of these characters. At the genus level, Phalaenopsis, Cleisostoma, and Sarcochilus are shown to be non-monophyletic.  相似文献   

4.
Luciobarbus barbulus (Heckel, 1847), a cyprinid fish of the Persian Gulf basin is re-described. Its identity is discussed and its phylogenetic relationship among the tribe Barbini is reconstructed. Luciobarbus barbulus can be distinguished from its close species, L. pectoralis by having thicker lower lip, stronger last unbranched dorsal fin ray and with stronger serration, longer barbels and posterior barbel passes the middle of the eye (vs. not reaching the middle of the eye in L. pectoralis), confirming the identity of both, as distinct species. Moreover, phylogenetic analysis based on the mtCOI sequences, placed the sequenced L. barbulus in a distinct clade corresponding to the tribe Barbini which includes Aulopyge, Barbus and Luciobarbus (three genera from Eurasia and North of Africa), sister to L. pectoralis from Orontes River with genetic distance of 1.7% applying the Kimura 2 Parameter (K2P) model.  相似文献   

5.
Currently choanoflagellates are classified into two distinct orders: loricate Acanthoecida and non-loricate Craspedida. The morphologically based taxonomy of the order Craspedida is in need of a revision due to its controversial, paraphyletic and inconsistent systematics and nomenclature. In this study, we add molecular data (SSU and parts of the LSU rDNA) of six new Craspedida species isolated from saline, brackish and freshwater habitats to the existing knowledge. Four of these six organisms could be described as new species: Paramonosiga thecata, “Salpingoeca” euryoecia, “Salpingoeca” ventriosa, “Sphaeroeca” leprechaunica, whereas two are assigned to previous morphologically described species: “Salpingoeca” fusiformis Saville Kent, 1880 and “Salpingoeca” longipes Saville Kent, 1880. Paramonosiga is established as a new genus of the Craspedida based on its phylogenetic position. Extending the dataset by six additional sequences shows that the craspedid taxonomy is still unsolved as the type specimen Salpingoeca gracilis has not yet been sequenced and hence a clear assignment to the genus Salpingoeca is not possible. Trying to assign morphological and ecological data to phylogenetic clades is not successful. We give an improved/emended morphological diagnosis for the two redescribed species and add molecular data for all six species, shedding light on their phylogenetic position.  相似文献   

6.
7.
Lycoperdon rupicola and L. subumbrinum are here described as new species. The former is a morphologically characteristic species forming small subglobose to pyriforme fruiting bodies with a prominent, protruding and stellately lobed stoma. In the phylogenetic analyses the six sequences of L. rupicola form a clade with 100% BS and 1.0 BPP, clustering with L. dermoxanthum. The proposed species grows among mosses on siliceous boulders and flat rocks as well as on open, sandy soil in temperate and hemiboreal regions. The records to date indicate its presence in Fennoscandia and Spain (Catalunya). L. subumbrinum morphologically resembles L. umbrinum but differs in having coarser ornamentation of its spores. In the phylogenetic analyses the five sequences of L. subumbrinum form a clade with 100% BS and 1.0 BPP, clustering with L. muscorum. The records to date, originating from southernmost Sweden and NW Slovakia, indicate that L. subumbrinum is a species of rich deciduous forests. L. muscorum is recorded for the first time from the Iberian peninsula (Spain).  相似文献   

8.
Zhao-Can Shen  Lei Chen  Long Chen  Yuan-Xi Li 《Genomics》2019,111(5):1059-1065
The taxonomic status and phylogenetic affinities of Mymaridae and Scelionidae are controversial, based on similarities between these families in the characteristics of adults, larvae, and eggs. In this study, we sequenced the mitochondrial (mt) genomes of representatives from these two families and found that the derived secondary structure of tRNA-Arg was the same in each family due to the absence of the D-stem. The segment of “cox1 trnL2 cox2 trnK trnD atp8 atp6 cox3” in Gonatocerus sp. (Mymaridae) is conserved and distinct from those of four other species of Chalcidoidea but similar to that in Proctotrupoidea and Platygastroidea. However, phylogenetic analysis indicated that Gonatocerus sp. was sister group to other species of Chalcidoidea. Comparisons based on complete gene orders may be more useful in a phylogenetic and systematic context, as different branches may exhibit partially homoplastic gene orders.  相似文献   

9.

Background

The number of species within the Malagasy genus Lepilemur and their phylogenetic relationships is disputed and controversial. In order to establish their evolutionary relationships, a comparative cytogenetic and molecular study was performed. We sequenced the complete mitochondrial cytochrome b gene (1140 bp) from 68 individuals representing all eight sportive lemur species and most major populations, and compared the results with those obtained from cytogenetic studies derived from 99 specimens.

Results

Interspecific genetic variation, diagnostic characters and significantly supported phylogenetic relationships were obtained from the mitochondrial sequence data and are in agreement with cytogenetic information. The results confirm the distinctiveness of Lepilemur ankaranensis, L. dorsalis, L. edwardsi, L. leucopus, L. microdon, L. mustelinus, L. ruficaudatus and L. septentrionalis on species level. Additionally, within L. ruficaudatus large genetic differences were observed among different geographic populations. L. dorsalis from Sahamalaza Peninsula and from the Ambanja/Nosy Be region are paraphyletic, with the latter forming a sister group to L. ankaranensis.

Conclusion

Our results support the classification of the eight major sportive lemur taxa as independent species. Moreover, our data indicate further cryptic speciation events within L. ruficaudatus and L. dorsalis. Based on molecular data we propose to recognize the sportive lemur populations from north of the Tsiribihina River, south of the Betsiboka River, and from the Sahamalaza Peninsula, as distinct species.  相似文献   

10.
This paper studies phenology and pollination ecology of an assemblage of nine small-flowered species of Asclepiadoideae–Asclepiadeae in a southern Ecuadorian mountain forest. These observations were augmented by laboratory studies of floral traits including scanning electron microscopy. Supported by multidimensional scaling analysis, three distinct pollination systems were identified: (a) pollination by small flies (Orthosia, Scyphostelma), (b) pollination by small bees and flies (Ditassa), and (c) pollination unspecialized (“Cynanchum”, Jobinia, Oxypetalum). Although numerous floral visitors were observed in the field, pollinaria were carried by only seven insect species. The average pollinaria removal rate of all species was low with 0.32±0.13%, and still lower for the pollinia insertion rate with 0.13±0.07%. The ratio of inserted pollinia to removed pollinaria was comparatively high with an average of 42.7±22.3%. If an insect achieved pollinia transfer, it did so very effectively. The complex floral morphology of the Asclepiadoideae has often been interpreted as a general trend toward specialization, but our observations indicate that the flowers are specialized functionally rather than ecologically.  相似文献   

11.
Korotnevella (Amoebozoa, Dactylopodida) is a genus of naked lobose amoebae with a dactylopodial morphotype. The cell membrane of these amoebae is covered with a monolayer of scales. The structure and size of scales are considered as species-specific features. Here, we describe a new marine species, Korotnevella mutabilis n. sp., isolated from the bottom sediment sample of Nivå Bay (Baltic Sea, The Sound) and studied with light and electron microscopy as well as with molecular phylogenetic analysis. This species has a number of morphological similarities with Korotnevella monacantholepis, such as size of the cell, L/B ratio, the nucleus structure and the type of a biotope from which both species were isolated. At the same time, Korotnevella mutabilis n. sp. differs from K. monacantholepis in the structure of basket-shaped scales: Korotnevella mutabilis n. sp. has an enclosed hammock-shaped latticework basket and up to two spines while K. monacantholepis has an opened two-row latticework basket and never has two spines. According to molecular phylogenetic analyses based on the sequences of the mitochondrial COI gene, Korotnevella mutabilis n. sp. is a distinct species, highly divergent from other Korotnevella species.  相似文献   

12.
A new species from Southern Patagonia, Isoparactis fionae sp. nov., is described. Isoparactis fionae sp. nov. differs from other species in the genus by having longitudinal rows of adherent rugae in the column, number of tentacles, cnidae and geographic distribution. We amend the generic position of the previously termed Paraisanthus fabiani (now Isoparactis fabiani comb. nov.), transferring it to Isoparactis as we discovered acontia in the type material of this species. We amend the binomen of Acraspedanthus ferax and use the correct binomen for the species Isoparactis ferax. In addition, we transfer the genus Isoparactis (previously within Bathyphelliidae as Acraspedanthus) to Isanthidae based on molecular evidence and because its diagnosis corresponds better with this family; we amend the diagnosis of Isanthidae accordingly. Finally, we discuss phylogenetic relationships within Isanthidae and among members of the superfamily Metridioidea. Our results show that Isanthidae is composed of derived acontiate sea anemones that have diversified in shallow waters of the Southern Hemisphere and that the family is putatively the sister group of a deep-sea lineage.  相似文献   

13.
The agamid Pseudotrapelus lizards inhabit the mountainous areas of the Arabian Peninsula and eastern North Africa. Currently six Pseudotrapelus species are recognised, though diagnostic morphological characters are still lacking, creating great difficulty in describing new species. Recently, two specimens of Pseudotrapelus were collected from the vicinity of Riyadh in central Saudi Arabia, an area that was not sampled in previous phylogenetic studies. In here we used both mitochondrial and nuclear data to investigate the phylogenetic position of the new samples, and assess their phylogenetic relationships with the other recognised species of Pseudotrapelus from across the distribution range of the genus. We used a multilocus approach of haplotype networks, concatenated datasets and species trees, performed mitochondrial and nuclear species delimitation analyses, and estimated divergence times. In general, our results support previous molecular studies and uncover the presence of cryptic diversity within Pseudotrapelus. The phylogenetic structure of the genus is of two major clades and within them seven distinct, delimited phylogenetic groups belonging to the six recognised species and the seventh to the individuals from Riyadh. The Riyadh specimens were distinct in all analyses performed. We suggest that the new specimens from the Riyadh area are a distinct lineage, forming a clade with their phylogenetic relatives, P. sinaitus and P. chlodnickii. The clade formed by these three species diverged during the Late Miocene around 6.4 Ma, with cladogenesis possibly facilitated by vicariance and isolation caused due to climatic fluctuations and the progression of sandy areas. Our results suggest further morphological research is necessary to revise the taxonomic status of this lineage and of the entire genus.  相似文献   

14.
15.
A new species of Trichoderma, Trichoderma guizhouense, isolated from soil in Guizhou Province, is described based on morphology and phylogenetic analyses. This species exhibits characteristic Trichoderma morphology but is distinct from related species based on characters of phialides and conidia. Two DNA markers, the translation elongation factor 1 alpha (tef1) and RNA polymerase II subunit b (rpb2) were used for phylogenetic analyses. The correlation between morphological and molecular-based clustering demonstrated two studied isolates are a new species.  相似文献   

16.
The leafcutter ants, which consist of Acromyrmex and Atta genera, are restricted to the New World and they are considered the main herbivores in the neotropics. Cytogenetic studies of leafcutter ants are available for five species of Atta and 14 species of Acromyrmex, both including subspecies. These two ant genera have a constant karyotype with a diploid number of 22 and 38 chromosomes, respectively. The most distinct Acromyrmex species from Brazil is A. striatus, which is restricted to the southern states of Santa Catarina and Rio Grande do Sul. Several cytogenetic and phylogenetic studies have been conducted with ants, but the karyotypic characterization and phylogenetic position of this species relative to leafcutter ants remains unknown. In this study, we report a diploid number of 22 chromosomes for A. striatus. The phylogenetic relationship between A. striatus and other leafcutter ants was estimated based on the four nuclear genes. A. striatus shared the same chromosome number as Atta species and the majority of metacentric chromosomes. Nuclear data generated a phylogenetic tree with a well-supported cluster, where A. striatus formed a different clade from other Acromyrmex spp. This combination of cytogenetic and molecular approaches provided interesting insights into the phylogenetic position of A. striatus among the leafcutter ants and the tribe Attini.  相似文献   

17.
In eastern North America, the field milkweed, Asclepias syriaca L. (Asclepiadaceae), is used in planting schemes to promote biodiversity conservation for numerous insects including the endangered monarch butterfly, Danaus plexippus (Linnaeus) (Nymphalidae). Less is known about its pollinators, and especially in urban habitats where it is planted often despite being under increasing pressure from invasive plant species, such as the related milkweed, the dog‐strangling vine (DSV), Vincetoxicum rossicum (Kleopow) Barbar. (Asclepiadaceae). During the A. syriaca flowering period in July 2016, we surveyed bees in open habitats along a DSV invasion gradient and inspected 433 individuals of 25 bee species in 12 genera for pollinia: these were affixed to bees that visited A. syriaca for nectar and contain pollen packets that are vectored (e.g., transferred) between flowers. Of all bees sampled, pollinia were found only on the nonindigenous honeybee, Apis mellifera (43% of all bees identified), as well as one individual bumblebee, Bombus impatiens Cresson. Pollinia were recorded from 45.2% of all honeybees collected. We found no relationship between biomass of DSV and biomass of A. syriaca per site. There was a significant positive correlation between A. syriaca biomass and the number of pollinia, and the proportion vectored. No relationship with DSV biomass was detected for the number of pollinia collected by bees but the proportion of vectored pollinia declined with increasing DSV biomass. Although we find no evidence of DSV flowers attracting potential pollinators away from A. syriaca and other flowering plants, the impacts on native plant–pollinator mutualisms relate to its ability to outcompete native plants. As wild bees do not appear to visit DSV flowers, it could be altering the landscape to one which honeybees are more tolerant than native wild bees.  相似文献   

18.
19.
Thirteen drosophilid species belonging to seven genera and two subfamilies are reported from three coral islands (namely Europa, Juan de Nova and Glorioso) that belong to the Scattered Islands in the Indian Ocean. Five species are cosmopolitan and five are African. Three are endemic to the insular Western Indian Ocean, including a presumably new Scaptodrosophila species. On the island of Juan de Nova, most captured flies had pollinia attached to the bases of their proboscis. DNA analysis using the rbcl gene revealed that these pollinia belong to the genus Leptadenia (Apocynaceae), of which a single species L. madagascariensis, endemic in Madagascar and Comoros, is present in this island. This is the first reported association between this plant and drosophilids.  相似文献   

20.
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