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1.
Summary Interspecific facultative social parasitism is well known in ants and in bumble-bees, but it is rarer in wasps. This form of parasitism is traditionally considered to be an intermediate stage in the evolution of obligate interspecific parasitism, where the parasites are no longer able to nest alone. We report field and experimental observations of a newly discovered facultative parasitic relationship between two closely related free-living Polistes species: P. nimphus and P. dominulus. P. nimphus foundresses sometimes usurp the nests of the larger P. dominulus before worker emergence. The invading queen takes over the nest with abundant abdomen stroking on the nest surface and is accepted by workers if they emerge 6 or more days after usurpation. Morphometric comparisons show that the usurper species, though smaller than its victims, has morphological adaptations consisting of larger heads, mandibles and front femora relative to their body size that may give it an advantage during nest invasion. This strategy is likely to be taken only after the foundress loses her original nest because invading P. nimphus queens have lower reproductive success than they would have had on their own nest. Overall, we found that P. nimphus usurpers use strategies of invasion similar to those of two obligate parasites, suggesting that this may be an example of one of the pathways by which social parasitism evolved.Received 4 April 2003; revised 8 August 2003; accepted 14 September 2003. 相似文献
2.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora:
Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii
,
Rumex densiflorus var. pycnanthus
,
R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage. 相似文献
3.
4.
We analysed the phylogenetic and phylogeographic relationships of four Mediterranean species of the rare slave-making ant
genus Chalepoxenus and eleven of its about 20 Temnothorax host species by sequencing the mitochondrial Cytochrome Oxidase I and II genes. Neighbour-Joining, Maximum Parsimony and
Bayesian analyses based on 1320 bp indicate that the genus Chalepoxenus constitutes a monophylum. In all three analyses, C. kutteri from Southwest Europe and the workerless, “degenerate slavemaker” C. brunneus from North Africa form a monophyletic group. C. muellerianus and C. tauricus, distributed in Southern Europe and Ukraine, respectively, form a monophylum in the Neighbour-Joining and the Maximum Parsimony
analysis. In our limited set of only 11 of several hundred Temnothorax species, T. flavicornis forms the sister group of Chalepoxenus. Our study further indicates paraphyly of the genus Temnothorax with respect to Chalepoxenus. Moreover, the results suggest that speciation in this slave-making genus is possibly caused by the formation of host races
as different Chalepoxenus species use different hosts, and some samples seem to cluster by host species rather than by geographical distance.
Received 5 September 2006; revised 17 March 2007; accepted 23 March 2007. 相似文献
5.
Madeleine M. Ostwald Selina A. Ruzi Kaitlin M. Baudier 《Journal of Insect Behavior》2018,31(5):503-509
Social insect colonies are high-value foraging targets for insectivores, prompting the evolution of complex colony defensive adaptations as well as specialized foraging tactics in social insect predators. Predatory ants that forage on other social insects employ a diverse range of behaviors targeted at specific prey species. Here, we describe a solitary foraging strategy of the ant Ectatomma tuberculatum, on nest guards of the stingless bee Tetragonisca angustula. We observed multiple instances of E. tuberculatum ambushing and successfully capturing the hovering and standing guards of T. angustula near nest entrances. The unique hovering behavior of the guard caste of this bee species, an adaptation to frequent cleptoparasitism by other stingless bees, may make these guards particularly vulnerable to ground-based, ambush attacks by E. tuberculatum. Likewise, the behavior of the foraging ants appears to adaptively exploit the defensive formations and activity patterns of these bees. These observations suggest an adaptive and targeted predatory strategy aimed at gathering external guard bees as prey from these heavily fortified nests. 相似文献
6.
In order to understand better non-target effect and potential uses, the host specificity of two parasitoid species (Anagyrus sp. nov. nr. sinope Noyes & Menezes and Leptomastix dactylopii Howard) (both Hymenoptera: Encyrtidae) for six mealybug species [Ferrisia virgata (Cockerell), Phenacoccus madeirensis Green, Phenacoccus solani Ferris, Planococcus citri (Risso),Pseudococcus longispinus (Targioni-Tozzetti) and Pseudococcus viburni (Signoret)] (all Hemiptera: Pseudococcidae) was studied through behavioral observations and laboratory rearing. The selected
mealybug species represent major subfamilies and tribes of Pseudococcidae. Except for F. virgata, all mealybug species induced examinations by Anagyrus sp. nov. nr. sinope and L. dactylopii. Anagyrus sp. nov. nr. sinope was specific to P. madeirensis, which was the only mealybug species selected for oviposition and suitable for complete development of the parasitoid. No
encapsulation of Anagyrus sp. nov. nr. sinope in P. madeirensis was observed. Leptomastix dactylopii accepted multiple species for oviposition, with the ranking of species preference as P. citri > P. viburni > P. longispinus > P. solani > P. madeirensis. Only P. citri, P. longispinus and P. viburni supported the development of L. dactylopii. Parasitoids developing in P. longispinus and P. viburni suffered from high encapsulation rates, while no encapsulation was observed when developing in P. citri. The results of this study suggest that Anagyrus sp. nov. nr. sinope is highly host specific. Leptomastix dactylopii, on the other hand, has a wider host range. The use of Anagyrus sp. nov. nr. sinope in a mealybug biological control program is limited to P. madeirensis and L. dactylopii to P. citri. The results presented in this study also lead us to question the accuracy of the reported host range of L. dactylopii, which include all six mealybug species tested. 相似文献
7.
We describe the extraordinary nesting habits of the fungus-growing ant Cyphomyrmex cornutus (Formicidae, Myrmicinae, Attini) and the natural history of Megalomyrmex mondabora (Formicidae, Myrmicinae, Solenopsidini), a social parasite that inhabits nests of C. cornutus and other small attine ants. The study was carried out at two sites on the Atlantic slope of Costa Rica. The C. cornutus nest is an oblong mass of accreted soil, attached to or suspended from low vegetation in wet forest understory. Less than
a fourth of the nest volume has chambers and is inhabited by C. cornutus; the remainder is a semi-solid mass of accreted soil often housing a variety of arthropods, including other unspecialized
commensal ant species. Five C. cornutus colonies examined were parasitized by M. mondabora. Colonies of M. mondabora inhabited chambers very near those of the host. In laboratory observations, M. mondabora and C. cornutus workers interacted with little aggression despite the consumption of C. cornutus larvae and fungi by M. mondabora. During most interactions, C. cornutus workers responded submissively, whereas M. mondabora appeared indifferent or nonresponsive. Megalomyrmex mondabora parasitizes several other attine species (Cyphomyrmex costatus, Cyphomyrmex salvini, and Apterostigma goniodes), and it appears therefore a relatively unspecialized social parasite with broad attine hostassociation. The size of M. mondabora workers vary with host species, suggesting M. mondabora sensu lato comprises either cryptic species or the host environment affects worker size.
Received 14 September 2006; revised 1 February 2007; accepted 6 February 2007. 相似文献
8.
A pea rust fungus, Uromyces viciae-fabae, has been classified into two varieties, var. viciae-fabae and var. orobi, based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of urediniospores and teliospores of 94 rust specimens from Vicia, Lathyrus, and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia, Lathyrus, and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae-fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum. These results suggest that U. viciae-fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.Contribution no. 184, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan 相似文献
9.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan. 相似文献
10.
M. E. Cocom Pech W. de J. May-Itzá L. A. Medina Medina J. J. G. Quezada-Euán 《Insectes Sociaux》2008,55(4):428-433
Euglossa viridissima is an orchid bee that forms both solitary and multiple female nests, making it a suitable species for the study of factors
leading to diverse degrees of sociality in Euglossines. We conducted observations in eight reused nests (where a first generation
of bees had been produced) kept in artificial boxes from the Yucatan Peninsula, Mexico. Five nests were reused (reactivated)
by a single female (SFN), two nests reused by a mother and one daughter (MFN1) and one nest reused by the mother and two daughters
(MFN2). No single nest was reactivated by unrelated females. The number of foraging trips, their duration and the duration
of cell provisioning was not different between SFN and MFN. The overall production of cells per female was not different either
between both types of nest. However, in MFN although all females did lay eggs, there was a reproductive skew in favor of the
mother (95 and 45% of the brood produced in MFN1 and MFN2 respectively). She showed reproductive control of her daughters
through oophagy and displaying threatening behavior when the daughters tried to open a cell where she had laid an egg. Brood
losses to parasites (Anthrax sp. (Bom-byliidae) and Hoplostelis bivittata (Megachilidae)) were only found in SFN which possibly reflects and advantage of MFN in this respect. Our results coupled
with other studies in Euglossa, reveal that a wide range of social behaviors occur in this genus, from solitary and communal to primitive reproductive division
of labor. Multiple factors involving different levels of pressure imposed by food availability and parasites may favor such
a diverse range of nesting behaviors. Interestingly, female associations in E. viridissima seem a result of kin selection that is enforced by coercion from mother females on their daughters. More studies are needed
to shed light upon the social organization of Euglossa and other Euglossines and on their phylogenetic relationships in order to trace the origins of eusociality in Apidae.
Received 12 February 2008; revised 25 June 2008; accepted 17 July 2008. 相似文献
11.
Fitness and life table parameters of two endoparasitoids of the obscure mealybug Pseudococcus viburni (Signoret), the solitary Leptomastix epona (Walker) and the gregarious Pseudaphycus flavidulus (Brèthes), were examined in relation to temperature and host size with a view to determine the efficacy of the parasitoids
as biocontrol agents of the pest. Three temperature levels (21°C, 26°C and 31°C) and two host sizes classes (small, which
mostly comprised third instar nymphs and large, which consisted of female adults) were studied. The lower developmental threshold
and thermal constant of the host and the parasitoids were found similar so the coincidence of pest and parasitoids is likely.
The rate of development of the parasitoids increased with a linear trend as the temperature increased from 21°C to 31°C. Temperature
had a significant effect on mummification in both parasitoid species and on successful parasitism by P. flavidulus. Host size had a significant effect on the mummification caused by L. epona and on the proportion of the male offspring which emerged as well as on the successful parasitism by P. flavidulus. Life table parameters of the parasitoids were estimated in small and large hosts at 26°C in the laboratory. Both parasitoids
achieved a greater intrinsic rate of natural increase and gross reproductive rate in addition to a shorter generation and
doubling time in large mealybugs compared with small ones. Consequently, large hosts are expected to have a higher impact
on the rise of the parasitoids population and the potential of the parasitoids to control the mealybug population improves
with the increase of host size.
Handling Editor: Torsen Meiners. 相似文献
12.
Zhengfang Zhang Yanming Sheng Keyi Jiang Zhao Wang Yuguo Zheng Qing Zhu 《Biotechnology letters》2010,32(4):513-516
A newly isolated Bacillus megaterium with epoxide hydrolase activity resolved racemic glycidyl (o, m, p)-methylphenyl ethers to give enantiopure epoxides in 84–99% enantiomeric excess and with 21–73 enantiomeric ratios. The (S)-enantiomer was obtained from rac-glycidyl (o or m)-methylphenyl ether while the (R)-epoxides was obtained from glycidyl p-methylphenyl ether. The observations are explained at the level by enzyme-substrate docking studies. 相似文献
13.
Esteban Paredes-Osses Katia Sáez Enrique Sanhueza Sonja Hebel Carlos González Carlos Briceño Apolinaria García Cancino 《Folia microbiologica》2017,62(5):437-444
In addition to the already known cagA gene, novel genetic markers have been associated with Helicobacter pylori (H. pylori) virulence: the dupA and vacAi genes. These genes might play an important role as specific markers to determine the clinical outcome of the disease, especially the vacAi gene, which has been expected to be a good marker of severe pathologies like gastric adenocarcinoma. In the present study, the association of cagA, dupA, and vacAi genes with gastroduodenal pathologies in Chilean patients was studied. One hundred and thirty-two patients positive for H. pylori were divided into two groups—non-severe and severe gastric pathologies—and investigated for the presence of cagA, dupA, and vacAi H. pylori virulence genes by PCR. The cagA gene was detected in 20/132 patients (15.2%), the vacAi1 gene was detected in 54/132 patients (40.9%), the vacAi2 gene was detected in 26/132 patients (19.7%), and the dupA gene was detected in 50/132 (37.9%) patients. Logistic regression model analysis showed that the vacAi1 isoform gene in the infected strains and the severity of the diseases outcome were highly associated, causing severe gastric damage that may lead to gastric cancer (p < 0.0001; OR = 8.75; 95% CI 3.54–21.64). Conversely, cagA (p = 0.3507; OR = 1.62; 95% CI 0.59–4.45) and vacAi2 (p = 0.0114; OR = 3.09; 95% CI 1.26–7.60) genes were not associated with damage, while the dupA gene was associated significantly with non-severe clinical outcome (p = 0.0032; OR = 0.25; 95% CI 0.09–0.65). In addition, dupA gene exerts protection against severe gastric pathologies induced by vacAi1 by delaying the outcome of the disease by approximately 20 years. 相似文献
14.
15.
16.
Kurtzman CP 《Antonie van Leeuwenhoek》2011,100(3):455-462
Ogataea
parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida
parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. O. parapolymorpha is closely related to Ogataea
angusta and Ogataea
polymorpha. The three species can be resolved from gene sequence analyses but are unresolved from fermentation and growth reactions
that are typically used for yeast identification. On the basis of multiple isolates, O. angusta is known only from California, USA, in association with Drosophila and Aulacigaster flies, O. parapolymorpha is predominantly associated with insect frass from trees in the eastern USA but O. polymorpha has been isolated from various substrates in the USA, Brazil, Spain and Costa Rica. 相似文献
17.
Three mitosporic fungi, i.e., Ardhachandra cristaspora, Dicyma pulvinata, and Sibirina gamsii from basidiomata of Aphyllophorales (Basidiomycetes), are described and illustrated. These fungi have not been previously reported in Japan. 相似文献
18.
19.
Seishi Kimura Daniel Golani Yukio Iwatsuki Motohiko Tabuchi Tetsuo Yoshino 《Ichthyological Research》2007,54(2):145-159
The Indo-Pacific marine atherinid fishes Atherinomorus forskalii (Rüppell, 1838), Atherinomorus lacunosus (Forster, 1801), and Atherinomorus pinguis (Lacepède, 1803) are redescribed as valid species based on the types and non-type specimens collected throughout the Indo-Pacific.
They are similar to each other chiefly in having a wide midlateral band (almost the same or greater than the midlateral scale
width), large mouth (posterior tip of upper jaw reaching to or beyond a vertical through anterior margin of pupil), and no
distinct tubercle at the posterior end of the dentary. All three species are distinguishable from congeners by those characters.
The three species have long been confused with each other or synonymized erroneously as a single species. Atherinomorus forskalii, known from the Red Sea and eastern Mediterranean, differs from Atherinomorus lacunosus and Atherinomorus pinguis in having conspicuous, large endopterygoid teeth, forming obvious tooth ridges. Atherinomorus lacunosus, widely distributed in almost the entire Indo-Pacific, from East Africa to Tonga, north to southern Japan, and south to northern
Australia, differs from Atherinomorus pinguis in having a wider midlateral band (the lower margin reaching to almost the center of the fourth scale row at level of the
anal fin origin vs. the lower margin reaching to the ventral end of the third scale row in Atherinomorus pinguis) and more numerous midlateral scales (40–44 vs. 38–41 in Atherinomorus pinguis). Atherina morrisi Jordan and Starks, 1906, Hepsetia pinguis mineri Nichols and Roemhild, 1951, Pranesus capricornensis Woodland, 1961, Pranesus maculatus Taylor, 1964, and Pranesus pinguis ruppelli Smith, 1965, are regarded as junior synonyms of Atherinomorus lacunosus. Atherinomorus pinguis is also widely distributed in the Indo-West Pacific, from East Africa to northern Australia and north to southern Japan.
Atherina pectoralis Valenciennes, 1835, is considered a junior synonym of Atherinomorus pinguis.
Supplementary material to this paper is available in electronic format at 相似文献
20.
Marta Herreros-Villanueva Maximiliano Rodrigo Manuel Claver Pilar Muñiz Enrique Lastra Carlos García-Girón Maria Jesus Coma del Corral 《Molecular biology reports》2011,38(2):1315-1320
To evaluate the KRAS, BRAF, EGFR, and HER2 gene status in colorectal cancer by novel techniques and evaluate whether anti-HER2 therapies could be offered in the treatment
of these patients. There are conflicting data on the prevalence of BRAF mutations and EGFR and HER2 gene amplification in colorectal KRAS wild type patients. In our study we tried to evaluate these expressions and their relationship to future treatment assays.
Clinical–pathological data and paraffin-embedded specimens were collected from 186 patients who underwent colorectal resections
at General Yagüe Hospital in Burgos, Spain. KRAS and BRAF status was analyzed by real-time PCR in all patients. EGFR and HER2/NEU gene amplification was detected using fluorescent in situ hybridisation technique (FISH) in 38 KRAS and BRAF wild type patients. KRAS mutations were present in 48% of the colorectal cancer patients. BRAF mutations were present in 6.25% of the KRAS wild type patients. EGFR and HER2 gene amplification was observed in 5.3% and 26.3%, respectively, of KRAS and BRAF wild type colorectal cancer patients. HER2, but not EGFR gene amplification, was frequently observed in KRAS and BRAF wild type colorectal cancer patients. These data indicate that HER2 amplification could be one of the genes to be considered in the therapeutic management of colorectal cancer. 相似文献