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1.
A combined taxonomic, morphological, molecular and biological study revealed that the species presently named Mecinus heydenii is actually composed of five different species: M. heydenii Wencker, 1866; M. raphaelis Baviera & Caldara sp. n., M. laeviceps Tournier, 1873; M. peterharrisi To?evski & Caldara sp. n. and M. bulgaricus Angelov, 1971. These species can be distinguished from each other by a few subtle characteristics, mainly in the shape of the rostrum and body of the penis, and the colour of the integument. The first four species live on different species of Linaria plants, respectively, L. vulgaris (L.) P. Mill., L. purpurea (L.) P. Mill. L. genistifolia (L.) P. Mill. and L. dalmatica (L.) P. Mill., whereas the host plant of M. bulgaricus is still unknown. An analysis of mtCOII gene sequence data revealed high genetic divergence among these species, with uncorrected pairwise distances of 9% between M. heydenii and M. raphaelis, 11.5% between M. laeviceps, M. heydenii and M. raphaelis, while M. laeviceps and M. peterharrisi are approximately 6.3% divergent from each other. Mecinus bulgaricus exhibits even greater divergence from all these species and is more closely related to M. dorsalis Aubé, 1850. Sampled populations of M. laeviceps form three geographical subspecies: M. laeviceps laeviceps, M. laeviceps meridionalis To?evski & Jovi? and M. laeviceps corifoliae To?evski & Jovi?. These subspecies show clear genetic clustering with uncorrected mtDNA COII divergences of approximately 1.4% from each other.  相似文献   

2.
Oriental river prawn, Macrobrachium nipponense, is a commercially important freshwater prawn species in China, Japan, Korea and Vietnam. Due to overfishing for food, the wild stocks M. nipponense are endangered. Twenty microsatellite loci were isolated from the M. nipponense. Twelve of these loci were polymorphic (seven to 16 alleles per locus), with expected heterozygosity ranging from 0.68 to 0.86 (n = 48). These polymorphic loci provide a valuable tool for assessing genetic diversity of wild and cultured populations.  相似文献   

3.
Aim The larval stages of marine taxa are often assumed to have an overriding influence on the phylogeographical structure of a species as well as on rates of speciation. Phylogeographical disjunctions in high‐dispersal marine taxa are generally attributed to historical events or contemporary ecological factors. The lack of genetic structure in low‐dispersal marine taxa is often ascribed to rafting by juveniles, yet few studies discuss the effects of historical conditions. Around peninsular Florida, there are three species of the crown conch, Melongena, which have direct‐developing, crawl‐away larvae. One of these species, M. corona, is subdivided into three subspecies. We refer to these five taxa as the corona complex. We assessed the validity of these taxa and tested for patterns of phylogeographical subdivision. Location Intertidal Florida and eastern Alabama, USA, Mexico and Panama. Methods The mitochondrial DNA cytochrome c oxidase subunit I, and ribosomal DNA 16S genes were sequenced from adult individuals representing all extant taxa of Melongena. Phylogenetic trees were constructed under maximum likelihood analysis (heuristic search with tree bisection–reconnection branch‐swapping) using the program paup *. Results Sequence variability in the complex was low and suggested no systematic or phylogeographical partitioning in the corona complex. The species complex probably consists of a single lineage exhibiting no clear pattern of genetic partitioning over the entire range. Main conclusions The present study supports the designation of only four extant species within the genus: M. corona, M. patula, M. melongena and M. bispinosa. The subspecies M. corona corona, M. c. johnstonei and M. c. altispira, and the species M. sprucecreekensis and M. bicolor, should all be considered to be M. corona. Surprisingly, even with very low larval and adult vagility, no population subdivisions were noted in our genetic analyses. Our analyses also substantiate the paraphyletic status of the family Melongenidae.  相似文献   

4.
The perennial grass triploid Miscanthus × giganteus is a promising renewable bioenergy feedstock in the United States and Europe. Originating from eastern Asia, this species is a sterile hybrid cross between M. sinensis and M. sacchariflorus. While research has begun to examine the impacts of M. sinensis and triploid M. × giganteus on the landscape, M. sacchariflorus has been largely overlooked in the peer‐reviewed literature. This review article discusses the origin, uses, distribution, and invasive potential of M. sacchariflorus. M. sacchariflorus is capable of producing high yields (10.7 t DM ha?1 yr?1), generally does not reproduce by seed, and can be challenging to establish due to poor cold tolerance, likely due to the limited germplasm used in evaluations. However, M. sacchariflorus has abundant and aggressively spreading rhizomes, which underscores its invasive risk. In the United States, it is listed as escaped from cultivation in at least eight states, primarily in the Midwest, although it is likely that not all populations have been reported. As such, it is essential to generate a comprehensive dataset of all known M. sacchariflorus populations and monitor any continued spread of this species.  相似文献   

5.
Abstract This paper deals with the genus Mindam Koch from China. The phylogeny of the genus is discussed. M. keteleerifoliae is regarded as the most advanced species, M. obliquus and M. piceasuc-tus are more advanced than M. abietinus, M. japonicus and M. victoria. The origin centre of the genus may be in Europe and the differentiation centre of the genus may be in Hengduan Mountains Region of China. Geological distribution of the genus shows island-shaped pattern. Five species from China was described in this paper, including one new species, M. piceasuctus Zhang and Qiao, one new subspecies, M. abietinus triprimesensori Zhang and Qiao and one newly recorded species, M. abietinus abietinus Koch 1856. A key to the Chinese species of Mindarus is given. The specimens of five species from China are deposited in the Institute of Zoology, Academia Sinica.  相似文献   

6.
The development of second‐generation energy crops on marginal land relies on the identification of plants with suitable physiological properties. In this study, we measured and compared leaf photosynthesis and water use efficiency of 22 populations from three Miscanthus species, M. lutarioriparius, M. sacchariflorus, and M. sinensis, planted in two experimental fields located in Qingyang of the Gansu Province (QG) and Jiangxia of the Hubei Province (JH) in China. QG is located in the Loess Plateau, one of the world's most seriously eroded regions particularly abundant in semiarid marginal land. At both locations, M. lutarioriparius produced the highest biomass and had the highest photosynthetic rates (A), with the growing‐season average of A reaching nearly 20 μmol m?2 s?1. Native to JH, M. lutarioriparius maintained a relatively high photosynthetic rate into the late growing stage in QG, for example, 15 μmol m?2 s?1 at temperature as low as 11.6 °C in October. All three species had higher water use efficiency (WUE) in semiarid QG than in warmer and wetter JH. In the late growing stage of M. lutarioriparius, instantaneous WUE (A/E) of the species nearly tripled in QG comparing to JH. Being able to maintain remarkably high photosynthetic rates when transplanted to a colder and drier location, these M. lutarioriparius populations serve as suitable wild progenitors for energy crop domestication in the Loess Plateau and other areas with the similar climates.  相似文献   

7.
A complex of closely related Mallomonas taxa belonging to the section Papillosae, M. kalinae ?ezá?ová and M. rasilis Dürrschmidt, has been studied in detail by molecular and morphometric methods. Our investigations uncovered the existence of a new species found in water bodies in Vietnam, which we describe here as Mallomonas furtiva sp. nov. This taxon is morphologically very similar to M. kalinae , from which it differs by minute, but statistically significant morphological differences on the structure of silica scales. Indeed, the principal component analysis of morphological traits measured on silica scales significantly separates all three species in the complex. Mallomonas kalinae and M furtiva differ by number of papillae on the shield and the dome, as well as by the scale sizes. Likewise, Mallomonas rasilis and M. furtiva are primarily differentiated by the absence of submarginal anterior ribs on silica scales of the former species. Phylogenetic analyses showed that Mallomonas furtiva is closely related to M kalinae , with which it formed a highly supported lineage. Distribution patterns of all three studied taxa are further discussed.  相似文献   

8.
In natural systems, pre‐adult stages of some insect herbivores are known to be attacked by several species of parasitoids. Under certain conditions, hosts may be simultaneously parasitized by more than one parasitoid species (= multiparasitism), even though only one parasitoid species can successfully develop in an individual host. Here, we compared development, survival, and intrinsic competitive interactions among three species of solitary larval endoparasitoids, Campoletis sonorensis (Cameron) (Hymenoptera: Ichneumonidae), Microplitis demolitor Wilkinson, and Microplitis croceipes (Cresson) (Hymenoptera: Braconidae), in singly parasitized and multiparasitized hosts. The three species differed in certain traits, such as in host usage strategies and adult body size. Campoletis sonorensis and M. demolitor survived equally well to eclosion in two host species that differed profoundly in size, Pseudoplusia includens (Walker) and the larger Heliothis virescens (Fabricius) (both Lepidoptera: Noctuidae). Egg‐to‐adult development time in C. sonorensis and M. demolitor also differed in the two hosts. Moreover, adult body mass in C. sonorensis (and not M. demolitor) was greater when developing in H. virescens larvae. We then monitored the outcome of competitive interactions in host larvae that were parasitized by one parasitoid species and subsequently multiparasitized by another species at various time intervals (0, 6, 24, and 48 h) after the initial parasitism. These experiments revealed that M. croceipes was generally a superior competitor to the other two species, whereas M. demolitor was the poorest competitor, with C. sonorensis being intermediate in this capacity. However, competition sometimes incurred fitness costs in M. croceipes and C. sonorensis, with longer development time and/or smaller adult mass observed in surviving wasps emerging from multiparasitized hosts. Our results suggest that rapid growth and large size relative to competitors of a similar age may be beneficial in aggressive intrinsic competition.  相似文献   

9.
Infochemicals are the most important cues used by parasitoids for host location. The attractiveness of infochemicals in a tritrophic context is expected to be determined by the degree of specialization of the parasitoid and its host(s). Microctonus hyperodae Loan (Hymenoptera: Braconidae) is an oligophagous parasitoid that attacks adult Curculionidae of the Brachycerinae subfamily, especially Listronotus bonariensis Kuschel, on Gramineae. In 1996, a new host–parasitoid association between the carrot weevil Listronotus oregonensis LeConte and M. hyperodae was created in the laboratory. In this study, the infochemicals used by M. hyperodae when searching for its adult weevil hosts were determined using a Y‐shaped olfactometer. Three curculionid species (L. oregonensis, Listronotus sparsus Say, and Neydus flavicaudis Boheman) and one bruchid species [Callosobruchus maculatus (Fabricius)], and their feces, were tested. It was expected that hosts phylogenetically and ecologically close to L. bonariensis would be more attractive than species less related but in fact, M. hyperodae responded only to L. oregonensis and its feces. When feces and host insects were tested separately, M. hyperodae responded to the odors emitted by L. oregonensis adults but not to their feces, suggesting that most of the kairomones came from the host itself. Host plants were also tested, but M. hyperodae responded neither to Lolium multiflorum Lamark (Gramineae) nor to Daucus carota L. (Umbelliferae) leaves.  相似文献   

10.
The genus Peganum (Zygophyllaceae) consists of six species and one subspecies; three of which are distributed in China, P. harmala Linn, P. nigellastrum Bunge and P. multisectum (Maxim.) Bobr. A probable new or intermediate species, Peganum sp., has been suggested in the wild in northwest China. Traditional classification in genus Peganum has focused on hairs on the plant surface. In this study, seed coat characteristics of Peganum species were investigated using light and scanning electron microscopy, demonstrating clear differences in morphology between species. In addition, DNA sequence data from two sequences (chloroplast: trnL‐F, psbA‐trnH) were used to differentiate Peganum sp. and study polygenetic relationships. Diversity in DNA sequences among Peganum species was found, with inter‐specific sequence divergence ranging from 0.6% to 5.6% in psbA‐trnH, and 0.0% to 1.8% in trnL‐F. The variations within species were low: from 0.0% to 0.4% in psbA‐trnH and 0.0% to 0.4% in trnL‐F. Therefore, Peganum species can now be easily identified as separate entities based on variations in DNA sequences. Phylogenetic trees were constructed from the combined data set for the two gene fragments, and the results indicate that Peganum sp. is monophyletic and sister to P. harmala and P. nigellastrum, while P. multisectum is also monophyletic. DNA data further confirmed that P. multisectum is an independent species and that a new species, Peganum sp., exists within the genus Peganum growing wild in China.  相似文献   

11.
Haukisalmi, V., Wickström, L. M., Henttonen, H., Hantula, J. & Gubányi, A. (2004). Molecular and morphological evidence for multiple species within Paranoplocephala omphalodes (Cestoda, Anoplocephalidae) in Microtus voles (Arvicolinae). —Zoologica Scripta, 33, 277–290. The present study was designed to test the hypothesis that the anoplocephalid cestode Paranoplocephala omphalodes (Hermann, 1783), a Holarctic parasite of Microtus voles, is a complex of host‐specific species, rather than a single host‐generalist species, using uni‐ and multivariate morphometrics and DNA sequence data from the mitochondrial cytochrome oxidase I gene. The phylogenetic methods applied to the mtDNA sequence data showed consistently that the cestodes morphologically recognizable as P. omphalodes include four well‐supported monophyletic groups, representing at least three distinct, largely host‐specific species. Multivariate morphometrics (discriminant analysis) successfully distinguished the four main mtDNA clades of P. omphalodes‐like cestodes. The true P. omphalodes is shown to be a parasite of Microtus arvalis, M. agrestis and Clethrionomys glareolus in Europe. Microtus oeconomus harbours two host‐specific, allopatric and possibly conspecific clades, one with a Holarctic and another with an (eastern) Beringian (Alaskan) distribution. The eastern Beringian endemic M. miurus is also parasitized with a host‐specific, morphologically divergent species of Paranoplocephala. The cestode clades recognized in M. oeconomus and M. miurus represent 2–3 undescribed species. Molecular phylogenetic analyses supported the monophyly of the ‘northern clade’ of Paranoplocephala spp., an assemblage including P. kalelai from Clethrionomys spp., P. macrocephala from Microtus spp. and all clades of P. omphalodes‐like cestodes except those representing the true P. omphalodes from Europe. The intra‐ and interspecific phylogeny within the northern clade is compared tentatively with the known evolutionary history of the hosts.  相似文献   

12.
We investigated interspecific competition between Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae) and Microplitis mediator (Haliday) (Hymenoptera: Braconidae) in their host, the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) under laboratory conditions. Cotton bollworm larvae were allowed to be parasitized by both wasp species simultaneously or sequentially at different time intervals. When host larvae were parasitized simultaneously by both parasitoids, the majority of the cocoons produced were of M. mediator. When host larvae were parasitized initially by M. mediator followed by C. chlorideae at 12 or 24 h, parasitoids emerging from the multiparasitized hosts were mainly M. mediator. In contrast, when host larvae were parasitized initially by C. chlorideae, followed by M. mediator 12 or 24 h later, parasitoids emerging from the multiparasitized hosts were mainly C. chlorideae. Dissections of host larvae at various time intervals after parasitization by the two parasitoids showed that first instars of M. mediator could physically attack the larvae of C. chlorideae, but not the eggs of C. chlorideae. When a host was parasitized by both wasp species sequentially, more host larvae died and the number of wasp offspring was significantly reduced compared to a host parasitized by only one wasp. Conversely, in simultaneous multiparasitism, the host mortality and wasp offspring production were not significantly different from those parasitized by single wasp species.  相似文献   

13.
该文描述了罂粟科绿绒蒿属三新种。(1)自四川西北部发现的二新种:肋蕊绿绒蒿,此种可能与拉萨绿绒蒿近缘,区别特征为此种叶片较狭,全缘,子房具4条纵肋;狭瓣绿绒蒿,此种可能与川西绿绒蒿近缘,区别特征为此种叶片较小,无毛,花瓣呈条状倒披针形。(2)自青海南部发现的一新种:短丝绿绒蒿,此种可能隶属于琴叶绿绒蒿亚属、滇西绿绒蒿组、滇西绿绒蒿系,与此系其他种的区别在于此种的披针状条形花瓣和较少、较短的雄蕊(花丝长1~5 mm)以及无花柱的雌蕊和被具短毛的硬毛子房。  相似文献   

14.
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   

15.
Two species of the genus Brachionycha Hübner –B. nubeculosa (Esper) and B. albicilia Sugi – are recorded for the first time from China. The adults and genital characteristics of the species are briefly redescribed with illustrations, and their distributions are given.  相似文献   

16.
Barth, D. Bernhard, D. Fritzsch, G. & Fritz, U. (2004): The freshwater turtle genus Mauremys— a textbook example of an east–west disjunction or a taxonomic misconcept? —Zoologica Scripta, 33, 213–221. We compare 1036 bp of the mitochondrial cytochrome b gene (cyt b) from all six Mauremys species with 16 other taxa, representing both currently recognized subfamilies of the Geoemydidae (Geoemydinae and Batagurinae) to contribute a comprehensive dataset towards resolving the conflicting Mauremys taxonomy and phylogeography. Mauremys, a representative of the Geoemydinae, is thought to be an example of a taxon with an east–west disjunction due to Pleistocene glacial extinction, with species occurring in the western Palearctic and species in the eastern Palearctic and Oriental regions. Our results contradict this traditional zoogeographical scheme and the current taxonomy of the Geoemydidae. Mauremys is paraphyletic with respect to two East Asian genera belonging to the Batagurinae: Chinemys and Ocadia. Therefore, Mauremys, as currently understood, clearly represents a taxonomic misconcept. Mauremys+Chinemys+Ocadia contains four well supported clades, two of which —M. japonica+Chinemys+Ocadia and M. annamensis+M. mutica— are confined to eastern Asia. The other two —M. caspica+M. rivulata and M. leprosa— occur in the western Palearctic. Mauremys leprosa may represent an ancient lineage which differentiated before the split between the other western and eastern species occurred. The patchy distribution of the four clades is likely the result of several ancient radiations rather than of a Pleistocene extinction. The sister‐group of Mauremys+Chinemys+Ocadia is Cuora, a morphologically highly specialized genus with a complicated shell hinging mechanism.  相似文献   

17.
Guo  Xiaoming 《Hydrobiologia》2000,429(1-3):115-131
Two new Mesocyclops species, M. mariae n. sp. and M. shenzhenensisn. sp., are described from southern China, the former species from Guangxi province, the latter from Guangdong province. Both species have setules on the medial margin of the caudal rami. Compared with each other, there are some conspicuous differences, such as the spinule pattern of the antenna basipodite, the structure of receptaculum seminis, the armature of coxopodite and basipodite of P4 and the armature of the caudal rami. The paper also compares the two new species with their supposedly closest relatives, M. pseudospinosus Dussart & Fernando, 1988, M. leuckarti(Claus, 1857) and M. pehpeiensisHu, 1943. In addition, other species of Mesocyclops in China are discussed and a key to 10 Chinese species of Mesocyclops is provided.  相似文献   

18.
Voracity and prey preference were evaluated for adult females of the predatory bugs Anthocoris nemorum (L.) and Anthocoris nemoralis (Fabricius) (Heteroptera: Anthocoridae) preying upon five species of aphids (Homoptera: Aphididae), of which Myzus persicae Sulzer, Aulacorthum solani (Kaltenbach), Macrosiphum euphorbiae (Thomas), and Aphis gossypii Glover are common pests in Danish glasshouse crops. Aphis fabae Scopoli was included to determine the influence of food quality on the preference of the predators, since A. fabae has proved to be of poor nutritional value to Anthocoris spp. The experiments were carried out over 24 h in climate cabinets at 20 °C, 60–70% r.h., L18:D6. The aphids were offered in equal amounts in combinations of two species in instars of comparable size. Myzus persicae served as a reference species in all combinations. Both predators accepted all five species of aphids as prey. The numbers of aphids killed per 24 h period varied between 3.7 and 18.0 for A. nemorum and between 3.6 and 12.7 for A. nemoralis. Field collected A. nemorum females, presumably in a state of reproductive diapause, killed in three of four prey combinations significantly more aphids than did ovipositing A. nemoralis females which originated from a commercial rearing. When A. nemorum females had terminated their reproductive diapause and commenced oviposition, voracity increased approximately threefold. When prey preferences were evaluated as a total number of killed prey, no difference in preference was found between the two Anthocoris species. Both predatory bugs preferred M. persicae to the other species, the most accepted alternative prey were A. gossypii, A. fabae, A. solani, and M. euphorbiae, in descending order. However, evaluating preference by number of aphids consumed, A. nemoralis showed a more pronounced preference for M. persicae, especially when combined with A. fabae. In nearly every case, A. nemoralis rejected A. fabae as a food item after killing the aphid. Thus, A. nemoralis exhibited a more specific food choice than A. nemorum. By killing and consuming different aphid species found in glasshouse crops – particularly M. persicae– both A. nemorum and A. nemoralis showed preliminary qualities as agents for the biological control of aphids.  相似文献   

19.
Larval growth and hatching days of lanternfishes Diogenichthys laternatus and Myctophum nitidulum (Myctophidae) collected in September 2012 in nearshore waters (<1 km offshore) at Mejillones Bay, northern Chile, were estimated on the basis of microstructure analyses of sagitta otoliths, to establish potential differences in early traits of both species from the productive coastal waters of the Humboldt Ecosystem. Growth increments were well defined, and no accessory primordia were observed in the analyses of the largest individuals in either species (8.61 and 9.17 mm BL, respectively). Both larval species displayed slow and similar growth rates: 0.057 ± 0.016 mm day?1 for D. laternatus, and 0.061 ± 0.005 mm day?1 for M. nitidulum. A large variability in the size‐at‐age in larvae of both species was detected. However, a recent otolith growth index showed all M. nitidulum in similar condition 5 days before capture, but with three D. laternatus in better condition and only one in a poorer condition than the other D. laternatus individuals. Growth trajectories estimated by the microincrement width of sagitta otoliths, indicated the presence of fast‐ and slow‐growing larvae for both species. Also, the back‐calculated ‘birth’ days suggest a large hatching pulse for D. laternatus near the third‐quarter moon. The small sampling size of M. nitidulum precluded a robust conclusion on hatching patterns, although most individuals were hatched between the third quarter and the new moon. It is suggested that the slow growth rates estimated for both larval species might be caused by cold waters from upwelling events and/or allometric growth during early development of these lanternfish.  相似文献   

20.
The Macrophya formosana group is reviewed and six species are recognized from Europe and East Asia, among them two new species, M. brevispuralis Li, Liu & Wei sp. nov. and M. pseudoformosana Li, Liu & Wei sp. nov. from China, and four known species, M. crassula (Klug 1817), M. dolichogaster Wei & Ma, 1997, M. formosana Rohwer 1916 and M. liukiuana Takeuchi 1926. A key to all known species of the Macrophya formosana group is provided.  相似文献   

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