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1.
Hymenachne panduranganii, a new species of Poaceae collected from a wetland area of Wayanad Wildlife Sanctuary in Kerala, which constitutes the core area of Nilgiri Biosphere Reserve (NBR), is described and illustrated. The new species differs from the related species H. assamica in having 1.0–1.5 m tall culms, 3.7–4.0 mm long spikelets, floret with a distinct lower palea and having only 2 stamens. To further enunciate the differences, an identification key to the Indian species of Hymenachne is provided.  相似文献   

2.
 The more than 200 wild and cultivated species relatives of potato (Solanum sect. Petota) present a valuable germplasm base for cultivar improvement. However, species boundaries and interrelationships within sect. Petota are controversial, inhibiting the efficient organization of the many germplasm collections of these species. One controversy involves questions of species boundaries and interrelationships of S. astleyi and S. boliviense. Solanum boliviense is narrowly endemic to two Departments in southern Bolivia, and S. astleyi is known only from one site entirely within the range of this species, where they co-occur. Both species are diploid and morphologically very similar. Artificial hybrids between them are fully fertile, and the species putatively hybridize naturally. These data have been interpreted to designate them as separate species or as S. astleyi an ecotype of S. boliviense. Putative progenitors of S. astleyi are S. boliviense, S. megistacrolobum subsp. megistacrolobum, and S. megistacrolobum subsp. toralapanum. We evaluated interrelationships among these species with random amplified polymorphic DNA’s (RAPDs) generated for 2 accessions of S. astleyi and 14 accessions of S. boliviense. These represent the entire geographic range of the former species and nearly the entire range of the latter. We also analyzed 1 accession each of S. acaule subsp. acaule, S. acaule subsp. aemulans, S. albicans, S. berthaultii, S. megistacrolobum subsp. megistacrolobum, S. megistacrolobum subsp. toralapanum, S. raphanifolium, S. sogarandinum, and S. sparsipilum. Phenetic analyses of the RAPD data show S. astleyi and S. boliviense to form two distinct groups and to be more similar to each other than to any of the other species investigated, suggesting that S. astleyi and S. boliviense are sister taxa. The divergence of S. astleyi and S. boliviense relative to other species examined suggests that they are worthy of taxonomic recognition at the subspecies, rather than species level, and we propose the new combination S. boliviense subsp. astleyi. Received: 21 November 1996 / Accepted: 18 April 1997  相似文献   

3.
Impatiens quadriloba K. M. Liu et Y. L. Xiang sp. nov. collected from the Siguniang Mountains Nature Reserve in northwestern Sichuan, China, is described and illustrated. The seed‐coat and pollen morphology of the new species are described and diagnostic morphological characters that distinguish the new species from the related I. falcifer Hook. f. are discussed.  相似文献   

4.
Interlocked DNA rings. II. Physicochemical studies   总被引:4,自引:0,他引:4  
J C Wang 《Biopolymers》1970,9(4):489-502
Several species of topologically interlocked λb2b5c DNA rings (catenanes) have been prepared in vitro. The sedimentation behavior of dimeric catenanes containing 0, 1, or 2 covalently closed duplex rings has been studied as a function of the superhelical density of the covalently closed ring or rings. In general, if XtpY represents rings X and Y topologically interlocked, the sedimentation coefficient of this species, SXtpY, is related to the sedimentation coefficients SX and SY of the component rings by the empirical relationship SXtpY/SY = [(MX + MY)/MY] [1 + (MX/MY)1.78(SY/SX)1.78]?0.56 This equation can also be extended to the case where three monomeric rings are topologically linked in a chain. For two topologically interlocked monomeric rings with neither ring covalently closed, the sedimentation coefficient is 1.35 times that of the monomeric ring. This is different from results reported for mitochondrial and P22 catenanes by others. Several possibilities are discussed to account for this discrepancy. The sedimentation coefficient of a species containing one covalently closed duplex ring and a single-stranded ring was also measured in an alkaline medium. This species, which can be easily derived from a dimeric catenane containing two covalently closed duplex rings, is particularly useful for the identification of covalently closed dimeric catenanes. Some electron microscopic studies of these interlocked rings are presented in an accompanying paper.  相似文献   

5.
The recent worldwide effort to transfer all non‐Australian taxa of Acacia s.l. mostly to the genera Senegalia and Vachellia follows the acceptance of the proposed re‐typification of the genus with an Australian species. The Madagascan species have, as yet, not been included in phylogenetic studies of Acacia s.l. and their position in the new generic classification of Acacia s.l. is therefore still unclear. In this study, plastid DNA sequence data were generated for seven Madagascan species, included in existing matrices for Acacia s.l. and analysed to assess the placement of these species. The results indicate that the Madagascan species are placed either in Senegalia or Vachellia and conform to the morphological characters used to distinguish these genera, despite some taxa having unusual red flowers. New combinations are formalized for Senegalia baronii , S . hildebrandtii , S . kraussiana ssp. madagascariensis , S . menabeensis , S . meridionalis , S . pervillei , S . pervillei ssp. pubescens , S . polhillii , S . sakalava , S . sakalava ssp. hispida , V achellia bellula , V . myrmecophila and V . vigueri . Nomenclatural errors are also corrected for three African taxa and, as such, new combinations are provided for Senegalia fleckii , S . hamulosa and V achellia theronii . © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 288–294.  相似文献   

6.
The alderfly genus Sialis is the most species‐rich group of the family Sialidae. However, discovery of new Sialis species is becoming difficult because of previous good faunal exploration. In this paper, we describe two new Sialis species from the southern part of East Asia, S. australis and S. jiyuni, based on materials from historical and recent collections. These two species are closely related to the insular species S. kumejimae and are among the early diverged species within Sialis. Presently, 32 species of Sialis are recorded from Asia. A key to all the Sialis species from Asia is provided.  相似文献   

7.
New collections from the Yangambi Biosphere Reserve (YBR) and Okapi Wildlife Reserve (OWR) revealed the presence of two groups of specimens similar to, but different from Marcusenius moorii. To study both these groups, an integrated morphological and genetic (mtDNA, cytb) approach was used. This study revealed that one of the two groups is conspecific with Marcusenius lambouri, a junior synonym of M. moorii, which is herein revalidated, with M. moorii longulus as its junior synonym. Marcusenius lambouri differs from M. moorii by a higher number of lateral line scales (44–46 vs. 40–43), a shorter pectoral-fin length (14.6–19.9 vs. 20.3–25.2% standard length; LS) and a more elongated body due to a usually shallower middle body depth (19.8–26.5 vs. 26.3–35.9% LS). The other group revealed to be a new species for science, Marcusenius verheyenorum, which can be distinguished from its congeners with eight circumpeduncular scales by the following unique combination of characters: a rounded head with a terminal mouth; a short and deep caudal peduncle (middle caudal-peduncle depth, 44.9–54.6% caudal-peduncle length; LCP), a deep body (middle body depth, 27.7–34.2% LS), 38–43 scales on the lateral line, 40–41 vertebrae, 20–21 dorsal-fin rays and 26 anal-fin rays. Some specimens previously attributed to M. moorii were examined and reassigned to M. lambouri or M. verheyenorum. As a result, M. moorii and M. lambouri occur in sympatry in the middle Congo Basin, with the distribution area of M. moorii still further extending into the lower Congo Basin. Instead, the distribution of M. verheyenorum is limited to some right bank tributaries of the upstream part of the middle Congo Basin. Two museum records from the Lilanda River (YBR), collected in the 1950s and previously identified as M. moorii, were re-identified as belonging to the new species, M. verheyenorum. However, the species now seems locally extinct in that region, which reflects the significant anthropogenic effects even within this reserve.  相似文献   

8.
The freshwater red algal genus Batrachospermum has been shown to be paraphyletic since the first molecular studies of the Batrachospermales. Previous research, along with this study, provides strong support for the clade Batrachospermum section Helminthoidea. This study has found that heterocortication, the presence of both cylindrical and bulbous cells on the main axis, is an underlying synapomorphy of this clade. Based on support from DNA sequences of the rbcL gene, the COI barcode region and the rDNA ITS 1 and 2, along with morphological studies, the new genus Sheathia is proposed. Seven heterocorticate species were recognized from the molecular clades. Sheathia boryana and S. exigua sp. nov. appear to be restricted to Europe, whereas S. confusa occurs in Europe and New Zealand. Sheathia involuta is widespread in the USA and reported for the first time from Europe. Sheathia americana sp. nov., has been collected in the USA and Canada, and S. heterocortica and S. grandis sp. nov. have been collected only in the USA. Sheathia confusa and S. grandis can be distinguished based on morphological characters, whereas DNA sequence data are required to conclusively distinguish the other species. Sheathia fluitans and S. carpoinvolucra also are placed within this genus based on the presence of heterocortication. These data also hint at greater diversity among non‐heterocorticate Sheathia than is recognized by the single species name S. arcuata.  相似文献   

9.
Pseudostellaria tianmushanensis G. H. Xia & G. Y. Li, collected from the Tianmu Mountains Nature Reserve in northwestern Zhejiang, China, is described and illustrated. This new species is similar to P. rupestris Pax., but differs by having a string of fusiform or ovoid‐globose tubers, leaves that are narrow elliptic‐lanceolate, glabrous, with cuneate base with scattered multi‐nodulate hairs, papillate margins and basipetalous variation in floral morphology. Moreover, the seed tubercle ornamentation also supports the recognition of the new species. A key to the species of Pseudostellaria in Zhejiang province is provided.  相似文献   

10.
The Malay civet (Viverra tangalunga) is found throughout Southeast Asia, but there have been very few studies on its natural history and ecology. We present here the results from the first radio telemetry study of this species on Peninsular Malaysia and compared our findings to similar studies on Borneo and Sulawesi. From August 2004 to August 2006, we captured 11 Malay civets in Krau Wildlife Reserve and radio-tracked seven adults (four males and three females). The mean weight of males (6.6 kg) was significantly higher than females (5.8 kg). Both sexes on Peninsular Malaysia were larger than their counterparts on Borneo and Sulawesi. There was no significant difference between the mean sizes of male and female home ranges on Peninsular Malaysia; the mean home range size for both sexes was 143 ha (95% MCP), which was larger than the mean range size recorded on Borneo and Sulawesi. We found that the Malay civet is a solitary, territorial species on Peninsular Malaysia: mean range overlap was 15% for males and 0% for females, and the home range of each male overlapped one or two females. Malay civets were mainly nocturnal, with some periods of rest during the night; daytime rest sites were within dense ground cover. Lowland forest is an essential habitat for this species; although Malay civets were sometimes found in plantations, they did not venture far from forested habitat.  相似文献   

11.
12.
In 1970 and 1973, during studies of primates in the Krau Game Reserve, Pahang, Peninsular Malaysia, experimental playbacks of tape recorded group calls of siamangSymphalangus syndactylus, resulted in increased activity in this forest-dwelling ape.  相似文献   

13.
Saussurea baoxingensis Y. S. Chen (Compositae, Cardueae), a new species of snow lotus from the Sichuan province, China is described and illustrated. It belongs to subgenus Amphilaena and is allied to S. muliensis. Morphological characteristics that distinguish the new species from S. muliensis are presented and discussed.  相似文献   

14.

The systematics of the Old World Spiranthes sinensis (Pers.) Ames species complex (Orchidaceae) has been complicated by its wide distribution and morphological variations. Within the species complex, S. australis Lindl. has been generally accepted as the only Spiranthes Rich. species distributed on the Japanese mainland. The present study provides morphological, phylogenetic, and ecological evidence for the recognition of S. hachijoensis Suetsugu as a new species of the S. sinensis species complex on the Japanese mainland. Spiranthes hachijoensis is morphologically similar to S. hongkongensis S.Y. Hu & Barretto and S. nivea T.P. Lin & W.M. Lin, sharing a degenerated rostellum, pollinia without a viscidium, and distinctly trilobed stigma. However, the taxon can be morphologically distinguished from S. hongkongensis by its glabrous rachis, ovaries, and sepals, and from S. nivea by its papillate labellum disc, larger papillate basal labellum callosities, and glabrous rachis, ovaries, and sepals. The autogamy and flowering phenology (i.e., earlier flowering) of S. hachijoensis are most likely responsible for premating isolation from the sympatric S. australis. A MIG-seq-based high-throughput molecular analysis indicated that the genetic difference between S. hachijoensis and its putative sister species S. sinensis is comparable to, or even greater than, the genetic difference between pairs of other species within the S. sinensis species complex. Our multifaceted approach strongly supports the recognition of S. hachijoensis as a morphologically, phenologically, phylogenetically, and ecologically distinct species.

  相似文献   

15.
Saussurea xinjiangensis Y. S. Chen, a new species from Xinjiang, China, is described and illustrated. It was first found during a field expedition by the author in 2014. It belongs to S. subgen. Saussurea sect. Laguranthera because its root and caudex split fibrously and it has numerous capitula in a corymbiform synflorescence. The new species is similar to S. mucronulata in its habit, strongly fibrous rootstock and caudex, sessile linear leaves and capitula shortly pedunculated in a corymbiform synflorescence. However, it differs from S. mucronulata by its usually branched stems (versus usually simple or apically few-branched), lower leaf blade 8–12 cm long and 0.5–1.8 cm wide (versus 3–5 cm long and 0.2–0.5 cm wide), leaves abaxially sparsely arachnoid tomentose (versus densely arachnoid tomentose), phyllary white arachnoid tomentose and green to brown (versus glabrous and blackish purple).  相似文献   

16.
报道了浙江省乌岩岭国家级自然保护区12种凤尾藓属(Fissidens)植物,其中内卷凤尾藓济州岛变种(F.involutus Wilson ex Mitt.var.jejuensis Y.-J.Yoon,B.C.Tan&B.-Y.Sun)为中国首次报道,该变种此前只分布在日本和韩国,其特征是背翅基部明显下延,鞘部细胞的...  相似文献   

17.
Stenomitos terricola FBCC-A190 was collected from soils around the trees of Mt. Gwanggyo, located in Yeongtong-gu, Suwon-si, Gyeonggi-do. S. terricola FBCC-A190 is a thin and simple filament with a cell length that is longer than its width. It has a thin and firm sheath, exhibiting a blue-green color. Species belonging to genus Stenomitos is semi-cryptic species with slight morphological differences from each other. They were confirmed as Stenomitos species by analysis using 16S rRNA and 16S–23S ITS. A monophyletic cluster was formed with the previously reported genus Stenomitos, with 16S rRNA gene sequences sharing similarities of 95.9–97.9% except for S. pantisii TAU-MAC 4318. In addition, 16S–23S ITS gene sequencing showed tRNAAla, tRNAIle and V2, similar to the previously reported genus Stenomitos. From these results, Stenomitos terricola sp. nov. was proposed as a new species belonging to genus Stenomitos.  相似文献   

18.
19.
Baudinella Thiele, 1931, Retroterra Solem, 1985 and Molema Köhler, 2011 are three genera of camaenid land snail endemic to coastal regions of the Western Australian Kimberley. Each of these genera has fairly distinct shells, but all exhibit a rather similar configuration of the reproductive system, which is characterized by lack of a penial sheath and presence of an elongated and coiled bursa copulatrix. By combining comparative morphology of shell and penial anatomy with analyses of the mitochondrial DNA fragments 16S rRNA (16S) and cytochrome c oxidase subunit 1 (COI), the phylogenetic relationships amongst representative species of these genera are addressed to test the monophyly of taxa and to identify new species. Our results show that all three genera are members of a single camaenid radiation. Five new species are described: two new species of Baudinella, B. magna n. sp. from the Institute and Montesquieu Archipelagos and B. margaritata n. sp. from Pitta Gorge in the Prince Regent Reserve, one new species of Molema, Molema tenuicostata n. sp., from near Talbot Bay, and two new species of Retroterra, R. dichroma, and R. nana, from the Prince Regent Reserve.  相似文献   

20.
The genus Stephanus Jurine (in Panzer) is newly recorded from Japan and is represented by a new species. S. anijimensis sp. nov. from Anijima Island of the Ogasawara Islands. This species resembles S. tridentatus van Achterberg & Yang from the Oriental part of China, but can be distinguished by the combination of following characters: pronotum with a cavity under pronotal fold (cavity absent in S. tridentatus); hind femur comparatively slender, 4.8–5.1 times as long as maximum width (about 4.1 times in S. tridentatus); apical 0.5 of hind femur black or blackish‐brown (more or less yellowish in S. tridentatus). This new species was not found from other islands of the Ogasawara Islands, in which fauna is being severely endangered mainly due to predation by the introduced green anoles. Recently, it was introduced into Anijima Island in March 2013 and thus the extinction risk of this species is very high on this island.  相似文献   

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