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1.
Gayon's recent claim that Buffon developed a concept of species as physical individuals is critically examined and rejected. Also critically examined and rejected is Gayon's more central thesis that as a consequence of his analysis of Buffon's species concept, and also of Darwin's species concept, it is clear that modern evolutionary theory does not require species to be physical individuals. While I agree with Gayon's conclusion that modern evolutionary theory does not require species to be physical individuals, I disagree with his reasons and instead provide logical rather than historical reasons for the same conclusion.  相似文献   

2.
Kengyilia longiaristata , a new species of Gramineae from Qinghai Province , is described .  相似文献   

3.
About 300 “species” names of Athyrium from China were published. They are preliminarily treated as 117 species with a number of varieties and hybrids. The complete enumeration will be reported in four parts. The present paper is part one, a key to the species.  相似文献   

4.
5.
The treatment of materials collected in Srednyaya Bight (Peter the Great Bay) revealed in a sample taken on December 3, 1986, a female Lamprops pumilioZimmer with oostegites (3.5 mm long). The sample was obtained using an Okean bottom sampler (with the mouth area of 0.25 m2), at a depth of 10 m, from fine sand, at a temperature of –1.5°C.  相似文献   

6.
The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes (2 females, 1 male) were sampled in Shangri-La, northern Yunnan, China, thus expanding their known distribution region towards the southeast. This site is the southeastern-most corner of the Tibetan Plateau and the southernmost tip of the Hengduan Mountains (Mts.). Phylogenetic analysis of mitochondrial (mt) and nuclear (n) DNA segments suggested that the three specimens belong to the genus ofThermophis. Morphologically, the new species is more similar toT. zhaoermii. However, it is distinguished fromT.zhaoermiiin the number of maxillary teeth (15), distance between the two eyes/head width, rostral width/height, mental width/height, in one character limited to female: head width/length, and in four characters restricted to male: occurrence of the reduction from 10 to 8 (8 to 6, 6 to 4) scales in each dorsal row on the tail. There are differences in morphology, genetics (mtDNA, nDNA), and geography between the putative new species andT.zhaoermii,the new species meets our proposed eclectic and feasible "four-differences" rule.  相似文献   

7.
A new species of the ant genus Aenictus Shuckard, A. henanensis, sp. nov., was collected from Yichuan County, Henan Province. The new species is close to A. lifuiae Terayama, but in profile view dorsum of propodeum straight, dorsum of petiolar node roundly convex, dorsum of propodeum entirely microreticulate. This new species is also close to A. ceylonicus (Mayr), but mandible with a large apical tooth, a small preapical tooth and followed by 5 indistinct minute denticles, subpetiolar process low and rounded, anterior half of pronotum microreticulate.  相似文献   

8.
We describe a new species from the family Salamandridae from northeastern Hunan Province of China based on morphological and molecular genetic evidences.The new species,Tylototriton liuyangensis,is a member of the T.asperrimus group,and shares a number of similarities with T.wenxianensis and T.broadoridgus.The dorsal surface of the new Tylototriton species is completely black,with nodule-like warts distributed evenly along the lateral margin of dorsal body,and there is no transverse striae between the warts.There are several diagnostic characters of the new species that differ from those of T.wenxianensis and T.broadoridgus as follows:(1)the interorbital space(IOS)is comparatively wide;(2)there is a bony ridge present on the dorsal head surface,running along the upper eyelids;(3)the space between axilla and groin(AGS)is comparatively large,with the mean male AGS approximately equal to 50%of the snout-vent length(SVL)and the mean female AGS being 53%of SVL;and(4)there is a small genital armature on the anterior angle of labial folds present inside the anal fissure of adult males during the breeding season.The result from the molecular phylogenetic analysis of the genus Tylototriton(including the type specimen of the new species)based on the complete DNA sequence of the mitochondrial ND2 gene(1035 bp)indicated that the new species was similar to T.wenxianensis,T.dabienicus,and T.broadoridgus,but formed an independent clade.This result was consistent with the morphological analysis above,supporting that the Liuyang Population represented a distinct species.  相似文献   

9.
Parisotoma notabilis is the most common species of Collembola in Europe and is currently designated as ubiquist. This species has been extensively used in numerous studies and is considered as well characterized on a morphological ground. Despite the homogeneity of its morphology, the sequencing of the barcoding fragment (5′ end of COI) for several populations throughout Europe and North America revealed four distinct genetic lineages. The divergence found between these lineages was similar to the genetic distance among other species of the genus Parisotoma included in the analysis. All four lineages have been confirmed by the nuclear gene 28S. This congruence between mitochondrial and nuclear signals, as well as the geographical distribution pattern of lineages observed in Europe, supports the potential specific status of these lineages. Based on specimens from the type locality (Hamburg), the species name was successfully assigned to one of these lineages. This finding raises several problems as Parisotoma notabilis has been widely used in many ecological studies. Accumulation of new data for the different lineages detected, especially ecological information and life history traits, is needed to help resolve this situation.  相似文献   

10.
The Cyclophragma undans nucleopolyhedrovirus(Cyun NPV), a potential pest control agent, was isolated from Cyclophragma undans(Lepidoptera: Lasiocampidae), an important forest pest. In the present study, we performed detailed genome analysis of Cyun NPV and compared its genome to those of other Group Ⅰ alphabaculoviruses. Sequencing of the Cyun NPV genome using the Roche 454 sequencing system generated 142,900 bp with a G + C content of 45%. Genome analysis predicted a total of 147 hypothetical open reading frames comprising 38 baculoviral core genes, 24 lepidopteran baculovirus conserved genes, nine Group Ⅰ Alphabaculovirus conserved genes, 71 common genes, and five genes that are unique to Cyun NPV. In addition, the genome contains 13 homologous repeated sequences(hrs). Phylogenetic analysis groups Cyun NPV under a distinct branch within clade ‘‘a' of Group Ⅰ in the genus Alphabaculovirus. Unlike other members of Group Ⅰ, Cyun NPV harbors only nine of the 11 genes previously determined to be specific to Group Ⅰ viruses.Furthermore, the Cyun NPV lacks the tyrosine phosphatase gene and the ac30 gene. The Cyun NPV F-like protein contains two insertions of continuous polar amino acids, one at the conventional fusion peptide and a second insertion at the pretransmembrane domain. The insertions are likely to affect the fusion function and suggest an evolutionary process that led to inactivation of the F-like protein. The above findings imply that Cyun NPV is a distinct species under Group Ⅰ Alphabaculovirus.  相似文献   

11.
This paper describes a new microstrobilus of palaeozoic Cycadaceae collected from the upper part of Lower Shihezi Formation, Dongshan Mine, Taiyuan, Shanxi, China and named it as Cycadostrobilus paleozoicus Zhu, gen. et sp. nov. This new cycad is the oldest microstrobilus to our knowlege of cycads. In the same locality and layer, there are Primocycas chinensis Zhu et Du, Sphenophyllum emarginatum Brongn. , S. costae Sterz. , S. verticallatum (Schloth.) Brongn. , S. oblongifolium (Germ. et Kaulf. ) Ung. , Tingia carbonica (Schenk.) Halle, T. hamaguchii Kon’no, Macrostachys huttoniformis Halle, Sphenopteris norinii Halle, S. firmata Sze, S. gothanii Halle, Sphenopteridium pseudogermanicum (Halle) Gu et Zhi, Pecopteris feminaeformis (Schloth.) Sterz. , P. wongii Halle, P. tuberculata Halle, P. unita Brongn. , P. taiyuanensis Halle, Emplectopteris triangularis Halle, Taeniopteris norinii Halle, T. spp. , Cordaites principalis (Germ.) Gein. , Cornucarpus patulus Halle, Radicites spp. and a few taxa unknown to palaeobotanical data. The authors consider that Cycadostrobilus paleozoicus is the same species as Primocycas chinensis, and its veg.etative leaves are similar to those of the genus Taeniopteris, e.g.T. norinii Halle.  相似文献   

12.
13.
Twelve species of the genus Cecidomyia have been reported from North America andEurasia. They are known as pine resin midges inhabiting mainly the pines, also spruce andfir. The larvae fecd on pitch and cause extensive primary damage to the hosts. The new res-in midge species here dealt with is known so far only from Jiangbian Forestry Bureau dis-trict, Yunnan.  相似文献   

14.
A fraction of magnetotactic bacteria was isolated by magnetic separation from the water and silt samples collected from the Ol’khovka River (Kislovodsk, Russia). A 16S rRNA clone library was obtained from the total DNA of the fraction by PCR amplification and molecular cloning. Phylogenetic analysis of 67 16S rRNA gene sequences of randomly selected clones demonstrated that two phylotypes of magnetotactic bacteria were present in the library: the first phylotype consisted of 42 sequences and the second one included only one sequence. The remaining 24 sequences belonged to non-magnetotactic bacteria. According to the results of phylogenetic analysis, both phylotypes were magnetotactic cocci; the predominant sequences were almost identical to the 16S rRNA sequence of the freshwater coccus TB24 (X81185.1) identified earlier among the magnetotactic bacteria isolated from Lake Chiemsee (Bavaria). The phylotype represented by a single sequence formed a separate branch in the dendrogram, with 97% similarity between its sequence and that of TB24. The discovered phylotypes formed with the sequences of uncultured freshwater magnetotactic cocci a separate branch within the class Alphaproteobacteria and presumably belonged to a separate family within the recently described order Magnetococcales. Despite the fact that phylogenetic analysis of the 16S rRNA clone library did not reveal any phylotypes of magnetotactic spirilla, after the secondary enrichment of the fraction of magnetotactic bacteria using the “race track” technique, a new strain of magnetotactic spirilla, Magnetospirillum SO-1, was isolated. The closest relative of strain SO-1 was the previously described magnetotactic spirillum Magnetospirillum magneticum AMB-1.  相似文献   

15.
Exceptionally well-preserved skulls and postcranial elements of a new species of the plesiomorphic stem macropodiform Balbaroo have been recovered from middle Miocene freshwater limestone deposits in the Riversleigh World Heritage Area of northwestern Queensland, Australia. This constitutes the richest intraspecific sample for any currently known basal “kangaroo”, and, along with additional material referred to Balbaroo fangaroo, provides new insights into structural variability within the most prolific archaic macropodiform clade – Balbaridae. Qualitative and metric evaluations of taxonomic boundaries demonstrate that the previously distinct species Nambaroo bullockensis is a junior synonym of B. camfieldensis. Furthermore, coupled Maximum Parsimony and Bayesian phylogenetic analyses reveal that our new Balbaroo remains represent the most derived member of the Balbaroo lineage, and are closely related to the middle Miocene B. camfieldensis, which like most named balbarid species is identifiable only from isolated jaws. The postcranial elements of Balbaroo concur with earlier finds of the stratigraphically oldest balbarid skeleton, Nambaroo gillespieae, and suggest that quadrupedal progression was a primary gait mode as opposed to bipedal saltation. All Balbaroo spp. have low-crowned bilophodont molars, which are typical for browsing herbivores inhabiting the densely forested environments envisaged for middle Miocene northeastern Australia.  相似文献   

16.
For over a century it has been believed that Alfred Russel Wallace and Henry Walter Bates set out for the Amazon in 1848 with the aim of “solving the problem of the origin of species”. Yet this enticing story is based on only one sentence. Bates claimed in the preface to his 1863 book that Wallace stated this was the aim of their expedition in an 1847 letter. Bates gave a quotation from the letter. But Wallace himself never endorsed or repeated this story. Many writers have acknowledged that this letter still survives. Yet the wording is different from that quoted by Bates and the letter says nothing of an expedition. It is argued that the sentence given by Bates is not a genuine quotation from this or any other Wallace letter but was modified by Bates to promote his own reputation. More significantly, this leads to the conclusion that there was a very sudden and dramatic shift in the way species were thought of and discussed after Darwin’s Origin of species appeared. Something called “the problem of the origin of species” (and similar variants) never occurred before Darwin’s book but exploded in frequency immediately after it. A profound change in how species origins were discussed happened which no one seemed to notice.  相似文献   

17.
The concept of species is one of the core concepts in biology and one of the cornerstones of evolutionary biology, yet it is rife with conceptual problems. Philosophers of biology have been discussing the concept of species for decades, and in doing so they sometimes appeal to the views of biologists. However, their statements as to what biologists think are seldom supported by empirical data. In order to investigate what biologists actually think about the key issues related to the problem of species, we have conducted a survey on the sample of 193 biologists from the population of biologists from over 150 biology departments at universities in the US and the EU. This article presents and discusses the results of the survey. Some results confirm and others falsify the reiterated statements of philosophers of biology as to what biologists think, but all results we obtained should be informative and relevant for future discussions of the problem of species.  相似文献   

18.
Genetic variability and structure of nonindigenous vs native populations are compared for the Eurasian round goby Neogobius melanostomus and the tubenose goby Proterorhinus marmoratus, which both invaded Lake St. Clair of the North American Great Lakes about 1990. The round goby spread rapidly to all of the Great Lakes and the tubenose goby largely has been restricted to Lake St. Clair, with some recent range extension into western Lake Erie. Risk analyses may indicate whether genetic variability of colonizers is predictive of their relative invasive and establishment successes. The present investigation examined DNA sequence variation across the left domain of the mitochondrial DNA cytochrome b gene in round and tubenose gobies from Eurasian and Great Lakes locations. We also sequenced six additional Neogobius species (including the monkey N.␣fluviatilis, racer N. gymnotrachelus, and bigheadN. kessleri gobies that have been ‘on the move’ in Europe) and the knout goby Mesogobius batrachocephalus from the Black Sea in order to develop diagnostic genetic characters to identify them in case of future and/or undetected invasions and to delineate their phylogenetic relationships. Results show that a diverse number of haplotypes characterize round and tubenose goby populations from both North America and Eurasian sites, fitting a risk analysis prediction of high genetic variability in their successful introductions. Phylogenetic results indicate that the current genus Neogobius is paraphyletic and that the subgenusApollonia thus should be elevated to the level of genus, containingApollonia (N.) melanostomus (the round goby) andA. (N.) fluviatilis (the monkey goby). In addition, there appear to be two separate species of Proterorhinus marmoratus, a marine P. marmoratus Pallas 1814 in the Black Sea (matching the original type locality), and a ‘cryptic’ freshwater species in the Danube and Dnieper Rivers and probably other Eurasian freshwater habitats, as well as invasive in the Great Lakes. We suggest resurrecting the name P. semilunaris Heckel 1837 for the freshwater species (a taxon that was originally described from rivers draining into the Aegean Sea and the Danube River, but was later placed in synonymy with P. marmoratus). An erratum to this article is available at .  相似文献   

19.
Exotic macrophytes, invertebrates and fish are found in most coastal habitats in the Mediterranean Sea. The Mediterranean Sea has been subjected to introductions of non-indigenous species by ship traffic since the opening of interoceanic maritime routes five centuries ago. The Sea, a hub of shipping, is exceptionally susceptible to invaders that arrive in fouling communities or ballast. The Suez Canal has been the largest pathway for the entry of these species: more than 300 Erythrean species – principally molluscs, fish, decapod crustaceans, polychaetes and algae – have become established in the eastern Mediterranean, primarily along the Levantine coasts. Mariculture of nonindigenous shellfish predominates in the northern Mediterranean lagoonar environments. Unrestricted transport of commercially important exotic shellfish has resulted in numerous unintentional introductions of pathogens, parasites and pest species. Some invaders have outcompeted or replaced native species locally, severely reducing biodiversity; some other invaders are so abundant they are exploited commercially. The rate of these biotic invasions has increased in recent decades, and they collectively have significant ecological and economic impacts in the Mediterranean Sea. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
This study presents the current knowledge on chemical composition, biological activity, and possible medicinal applications of Phellinus igniarius, Phellinus pini, Phellinus pomaceus, and Phellinus robustus. These inedible arboreal species are phytopathogens that cause the enzymatic decomposition of wood. These species belong to the medicinal mushrooms and have been known for centuries in the traditional medicine of the Far East. They have been used as an effective remedy for stomach and intestinal ailments, diarrhea, and hemorrhages. Mycochemical studies have proved the presence of polysaccharides, phenolic compounds, and terpenoids. These compounds show biological activities such as anticancer, antioxidant, antiangiogenic, and antiviral. Research studies conducted using modern analytical methods have advanced the knowledge on the potential therapeutic use of compounds isolated not only from the fruiting bodies but also from biomass obtained with in vitro biotechnological methods.  相似文献   

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