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1.
Nomenclatural benchmarking is the periodic realignment of species names with species theories and is necessary for the accurate and uniform use of Linnaean binominals in the face of changing species limits. Gaining access to types, often for little more than a cursory examination by an expert, is a major bottleneck in the advance and availability of biodiversity informatics. For the nearly two million described species it has been estimated that five to six million name-bearing type specimens exist, including those for synonymized binominals. Recognizing that examination of types in person will remain necessary in special cases, we propose a four-part strategy for opening access to types that relies heavily on digitization and that would eliminate much of the bottleneck: (1) modify codes of nomenclature to create registries of nomenclatural acts, such as the proposed ZooBank, that include a requirement for digital representations (e-types) for all newly described species to avoid adding to backlog; (2) an "r" strategy that would engineer and deploy a network of automated instruments capable of rapidly creating 3-D images of type specimens not requiring participation of taxon experts; (3) a "K" strategy using remotely operable microscopes to engage taxon experts in targeting and annotating informative characters of types to supplement and extend information content of rapidly acquired e-types, a process that can be done on an as-needed basis as in the normal course of revisionary taxonomy; and (4) creation of a global e-type archive associated with the commissions on nomenclature and species registries providing one-stop-shopping for e-types. We describe a first generation implementation of the "K" strategy that adapts current technology to create a network of Remotely Operable Benchmarkers Of Types (ROBOT) specifically engineered to handle the largest backlog of types, pinned insect specimens. The three initial instruments will be in the Smithsonian Institution(Washington, DC), Natural History Museum (London), and Museum National d'Histoire Naturelle (Paris), networking the three largest insect collections in the world with entomologists worldwide. These three instruments make possible remote examination, manipulation, and photography of types for more than 600,000 species. This is a cybertaxonomy demonstration project that we anticipate will lead to similar instruments for a wide range of museum specimens and objects as well as revolutionary changes in collaborative taxonomy and formal and public taxonomic education.  相似文献   

2.
Although three species of the genus Macrourus are recognized in the Southern Ocean, DNA sequencing of the mitochondrial COI gene revealed four well-supported clades. These barcode data suggest the presence of an undescribed species, a conclusion supported by meristic and morphometric examination of specimens.  相似文献   

3.
Two undescribed species of microsporidia were found in mass-reared Phytoseiulus persimilis Athias-Henriot from two commercial sources during a routine examination of these predators for pathogens. Both microsporidian species were described from specimens that had been prepared for transmission electron microscopy; live specimens were unavailable for examination. One microsporidium, identified as Species A, was described from two specimens obtained from a commercial insectary in North America. All observed stages of this microsporidium were uninucleate. Rounded-to-ovoid schizonts appeared to develop in direct contact with the cytoplasm of lyrate organ cells (ovarian tissue). Mature spores of Species A were elongate-ovoid and measured 2.88 x 1.21 microm. A polar filament coiled 7 to 10 times in the posterior half of the spore. Sporoblasts and spores were observed in the cytoplasm of cells of numerous tissues and in developing eggs within gravid females. A second species, identified as Species B, was described from five specimens obtained from a commercial source in Israel. All observed stages of this microsporidium were uninucleate. Schizonts of Species B were observed within the cytoplasm of cecal wall cells and within the nuclei of lyrate organ cells. Mature spores were ovoid and measured 2.65 x 1.21 microm. A polar filament coiled 3 to 4 times in the posterior half of the spore. Densely packed ribosomes often concealed the polar filament and other internal spore characteristics. Spores were observed in the cytoplasm of cells of numerous tissues and occasionally within the nuclei of lyrate organ cells. Numerous spores and presporal stages were observed within the ovary and developing eggs. The development and pathology of Species A and B were compared to those of Microsporidium phytoseiuli Bj?ornson, Steiner and Keddie, a microsporidium previously described from P. persimilis obtained from a commercial source in Europe. The occurrence of three species of microsporidia within P. persimilis from three sources raises questions regarding the origin of these pathogens. Because microsporidia may have profound impact on the performance of P. persimilis, consideration must be given to the identification and exclusion of microsporidia from field-collected specimens or from predators that may be shared among commercial sources.  相似文献   

4.
该文在野外调查、标本采集、标本查阅与鉴定及文献考证的基础上,订正了广西长柱开口箭属(Tupistra Ker-Gawl.)植物,确定广西目前分布有3种,其中红柱开口箭(Tupistra cardinalis Aver.,N. Tanaka&Son)为中国新记录植物。同时,还详细描述了红柱开口箭的形态特征,并提供广西产长柱开口箭属植物照片和地理分布信息以及国产长柱开口箭属的分类检索表,以资鉴定。  相似文献   

5.
The cyamids collected from a True's beaked whale (Mesoplodon mirus), a common dolphin (Delphinus delphis), and a harbour porpoise (Phocoena phocoena) stranded in Galicia (NW Spain) were identified as Isocyamus deltobranchium, extending the range of this species to the Atlantic Ocean. The three cetacean species examined are new hosts for this parasite. The microscopic examination of female specimens reveals that certain important taxonomic characters can be present or absent depending on the maturation stage, an aspect which should be considered in future studies describing cyamid species.  相似文献   

6.
The taxonomy ofGentiana (Gentianaceae), sect.Pneumonanthae, in eastern North America is reviewed. Two species and one variety recognized in recent literature are reduced to synonymy, while one overlooked variety is restored to recognition. Distributional data include several reductions in range resulting from examination of previously misidentified specimens. Thirteen species are native to eastern North America; all are restricted to it. Of these, three are primarily prairie species; three, Appalachian; three, coastal plain; two, southern plateau; one, eastern boreal; and one, Great Lakes region to central boreal. Interfertility and occasional natural hybridization are present even among the most morphologically diverse species.  相似文献   

7.
A survey of xeniid octocorals was carried out in the waters off Southwestern Thailand in September, 2007. Microscopic investigation of the colonies revealed that three specimens belonged to the genus Ovabunda. Gross morphological examination is presented here accompanied by scanning electron micrographs of the sclerites. Molecular phylogenetic analysis showed identical genotypes at mtMutS, COI, and 28S rDNA for all three specimens and supports their generic assignment. Colony size and shape, sclerite size, and pinnule arrangement differ from nominal species of Ovabunda and thus a new species, O. andamanensis is introduced here. This work also presents a new eastern geographical record for the genus Ovabunda.  相似文献   

8.
Sushil Kumar Parai  Tarunendu Ghose 《CMAJ》1985,132(12):1381-1384
Laboratory examination of specimens from 123 consecutive renal biopsies performed at Victoria General Hospital, Halifax revealed six cases of mesangial deposition, predominantly of IgA, unassociated with systemic disorders. Immunohistologic examination showed deposits of only IgA in one specimen, IgA and IgG in two and IgA, IgG and IgM in three. Glomerular deposits of C3 were seen in five of the specimens, and properdin was seen in three. Glomeruli in all the specimens showed increased matrix and increased numbers of cells in the mesangium. Electron microscopy revealed deposits in the mesangium or capillary wall in all five of the specimens so studied. All six patients had proteinuria, four had microscopic hematuria, and three had hypertension; in one patient the disease progressed to renal failure.  相似文献   

9.
Palaeocastorine beavers were diverse members of the burrowing fauna of the Oligocene of North America best known from the Great Plains and the Great Basin. Palaeocastorines are also found in the northern Rocky Mountains. Several specimens of Capacikala, Euhapsis, and Palaeocastor have been reported from Montana within the Cabbage Patch beds fauna. New occurrences of palaeocastorine beavers from the Fort Logan Formation of central Montana show that the fauna there included Palaeocastor fossor, Capacikala sp., Palaeocastor sp., and three specimens of a species previously known only from the John Day Formation of Oregon: Palaeocastor peninsulatus. The three specimens include crania and associated postcrania forming an ontogenetic series from a juvenile to a mature adult. Careful examination of these specimens shows that morphological changes throughout ontogeny are associated with increased burrowing ability in adults. Palaeocastor peninsulatus is a scratch-digger with few cranial adaptations to burrowing susceptible to change with maturity. Dental characters, however, are modified with wear and vary greatly across individuals of similar wear stage. Cranial morphology thus appears to be a reliable source of taxonomic information in palaeocastorines unlike dental material. These new specimens provide evidence for increased chisel-tooth digging in adults compared to juveniles as is observed throughout the evolution of palaeocastorines. This study demonstrates the need for future work focusing on intraspecific variation to help better define species boundaries among palaeocastorines and improve phylogenetic analyses.  相似文献   

10.
《Journal of Asia》2014,17(3):333-338
Graphium butterflies are famous in Peninsular Malaysia for their colourful wings, yet their taxonomy remains unresolved. The popular guides to Malaysian butterflies, place the species in one, two or three genera and identification to species using obscure morphological characters can be difficult, especially for the closely related species, G. bathycles bathycloides and G. chironides malayanum. We sequenced the COI mtDNA barcode for Graphium specimens in the Museum of Zoology, University of Malaya to test the utility of DNA barcoding for the identification of Graphium species. Additionally, we sequenced 28S rRNA to examine, in conjunction with COI, the phylogenetic relationships of these species and investigate the validity of Pathysa and Paranticopsis as distinct genera. We found that all species of Graphium possessed a distinctive cluster of DNA barcodes with the exception of specimens originally identified as G. bathycles bathycloides and G. chironides malayanum which shared DNA barcodes. On further examination we found that the morphological determinations were ambiguous as the specimens overlapped for diagnostic characters reported for each species. The COI and 28S rRNA phylogenetic trees showed a similar topology with Paranticopsis species forming a clade nested within a larger clade also comprising Pathysa species. Based on this topology, in order for Pathysa to be a valid genus, at least three other clades within Graphium s.l. would also have to be raised as genera.  相似文献   

11.
12.
基于对国内外大量文献研究以及对国内外多个标本馆的植物标本的广泛检视,同时针对2个物种开展了分子系统发生分析。根据形态学与分子系统学证据,报道了发现于新疆阿勒泰地区的2种中国新分布记录被子植物,分别为蒙古水毛茛[Ranunculus mongolicus(Krylov)Serg.]和山地柳叶菜(Epilobium montanum L.)。凭证标本保存于北京林业大学标本馆(BJFC)、中国科学院植物研究所标本馆(PE)和中国科学院昆明植物研究所标本馆(KUN)。  相似文献   

13.
蓟马(昆虫纲:缨翅目)是昆虫纲中有重要经济意义的目之一,由于个体微小,因此需要制作成高质量的玻片在高倍显微镜下观察和研究。如果玻片标本质量欠佳,常常导致无法鉴定其种类。不同的研究中处理蓟马标本的技术和方法各异。本文介绍一种新的制片方法,这一方法需要更少的化学药品,且适合处理深颜色的标本。而且,用这个方法处理的标本清晰,保持其自然体色,这些特征在鉴定种类时是十分必要的。本方法处理标本包括4个步骤:氢氧化钾透明(一般5%一10%KOH溶液中,常温放置1~2d或者100℃水浴加热1~2h,处置时间随材料大小和颜色的深浅有所变化)、纯酒精脱水(材料透明后转移到纯酒精中浸泡4—5min)、Hoyer's介质装片(滴一滴Hoyer's介质于载玻片中央,而后将脱水后的材料转移至介质中,用细拨针小心整翅、足以及触角的姿态,盖上盖玻片)和干燥贴标签(装片后放置在35~45℃烘箱中2~3d或者室温下放置1星期,然后将采集信息、寄主信息以及鉴定表格制成标签,贴于玻片两侧),与其它制片方法相比,此法最简洁。文末对不同的制片方法作了比较和讨论。  相似文献   

14.
Critical examination of the literature and specimens of the three described species of Euthora indicates that the acceptance of the northern species E. cristata (C. Ag.) J. Ag. and E. fruticulosa (Rupr.) J. Ag. has been based on lack of familiarity with the degree of variation normal within one species, and these two species should be united. The carpogonial branch system of this combined species is typical of that found in the genus Callophyllis within which it should therefore be included as Callophyllis cristata (C. Ag.) Kütz. The taxonomic position of the only other species of Euthora, E. tristanensis Baardseth, cannot be determined until information on the carpogonial structure is available.  相似文献   

15.
Zhou LW  Dai YC 《Mycologia》2012,104(4):915-924
During the examination of specimens of Theleporus and Grammothele (Polyporales, Basidiomycota) from tropical China, three new species, Theleporus membranaceus, T. minisporus and Grammothele denticulata, were identified based on both morphological and phylogenetic analyses. They are described and illustrated. T. membranaceus is characterized by its extremely thin basidiocarps (0.12 mm), small pores (7-10 per mm) and ellipsoid to broadly ellipsoid basidiospores. T. minisporus has the smallest basidiospores among the species in the genus. Grammothele denticulata is distinguished in the genus by gray pores, continuous hymenia over dissepiment edge and cylindrical basidiospores with tapering apex. Two annotated identification keys are provided for species thus far accepted in Theleporus and Grammothele. The phylogenetic relationships of Theleporus and Grammothele were inferred based on nITS sequences and are briefly discussed. The molecular evidence showed that Theleporus and Grammothele belong to the core polyporoid clade.  相似文献   

16.
The presence of the opal chimaera, Chimaera opalescens, is reported for the first time in the deep waters of the Azores, with the capture of four specimens by fishermen and the video recording of an additional five individuals. Species identification was supported by the 646 bp sequenced fragment of the mitochondrial gene cytochrome oxidase subunit I. Because C. opalescens is a recently recognised species that had been recurrently misidentified as rabbitfish, Chimaera monstrosa, the historical data of C. monstrosa in the Azores were reviewed to assess the possible presence of both Chimaera species in the region. Although several authors have reported the occurrence of C. monstrosa in the Azorean waters since the 1800s, the majority of these are based on only three specimens caught during the late 1800s. The investigation performed using literature and examination of the museum specimens still available concluded that the most likely scenario is that C. monstrosa is absent from the Azores and past records of that species in the region are most likely misidentifications of C. opalescens.  相似文献   

17.
研究了青藓科的7种1变种(Brachythecium planiusculum,Eurhynchium coarctum,E.serricuspis,Rhynchostegium leptomitophyllum,R.longirameum,R.pallenticaule,R.subspeciosum和R.subspeciosum var.filiforme)的模式标本。提出了3个新组合(E urhynchium longirameum,E.filiforme,Bryhnia serricuspis),  相似文献   

18.
Based on critical examination of both fresh and dried specimens and a morphometric analysis of herbarium specimens we performed a comparative study of the three closely related Gastridium (Poaceae, Tribe: Poeae, Subtribe: Agrostidinae) species G. ventricosum, G. phleoides and G. scabrum collected in Italy. The study aimed to provide new diagnostic tools to improve the taxonomy of the genus and confirm species delimitation. Variation in floral morphology in the three species was explored using seven quantitative and ten qualitative characters measured on 318 spikelets, both awned and unawned. Statistical methods, including principal components analysis (PCA) and non‐metric multidimensional scaling (NMDS), were used. Numerical analyses showed a general distinctness of spikelets and florets, consistent with the three studied species, and revealed among and within species variation patterns in both spikelet types. Accordingly, the most informative quantitative characters appeared to be the width and length of glumes and the length of awns, useful to distinguish G. phleoides which has the narrowest glumes and longer awns than the other species, while G. scabrum has the widest glumes. The most informative qualitative characters appeared to be the presence/absence of thick hairs or minute tubercles on the upper side of the lemma. The autonomy of the three studied species was confirmed. The taxonomic significance of the results is briefly discussed, and notes on the species distribution are included. Some nomenclatural and taxonomic notes on G. scabrum, of which literature still showed evidence of a general unawareness, are provided.  相似文献   

19.
Polydactylus konadaensis Mishra and Krishnan, 1993 was described on the basis of two specimens from Konada, Andhra Pradesh, east coast of India. Although the new species was placed in the genus Polydactylus, our examination of the type specimens of the species showed them to represent a species of Filimanus. Furthermore, the characters of those specimens were consistent with those of the lectotype, paralectotype, and other specimens of F. xanthonema (Valenciennes in Cuvier and Valenciennes, 1831). Accordingly, Polydactylus konadaensis is herein regarded as a junior synonym of F. xanthonema. Received: July 2, 2000 / Revised: November 2, 2000 / Accepted: January 12, 2001  相似文献   

20.
The only previously known Mesozoic fossils of the chilopod order Geophilomorpha are two species from the Late Jurassic and Late Cretaceous, both known from single specimens that cannot be assigned with precision to a family. Four specimens from the Late Cretaceous (earliest Cenomanian) amber of Burma include three that can be identified as conspecific, described here as Kachinophilus pereirai gen. nov. sp. nov. These specimens preserve greater morphological detail in comparison with other fossil geophilomorphs: the form and fine features of the head, the maxillary complex, the trunk sternites with associated glandular pores and the ultimate pair of legs defend the assignment of the species to the extant family Geophilidae, and most probably to a derived subgroup including well‐known extant genera such as Ribautia Brölemann, 1909. Confocal laser scanning microscopy supplements examination under incident and transmitted light to document details of high taxonomic relevance in the head and the forcipular segment. The modern appearance of this species and its membership among deeply nested extant clades are consistent with molecular estimates that most of the diversity of crown‐group Geophilomorpha originated before the Late Cretaceous.  相似文献   

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