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1.
Wilkinson EB  Feener DH 《Oecologia》2007,152(1):151-161
Species must balance effective competition with avoidance of mortality imposed by predators or parasites to coexist within a local ecological community. Attributes of the habitat in which species interact, such as structural complexity, have the potential to affect how species balance competition and mortality by providing refuge from predators or parasites. Disturbance events such as fire can drastically alter habitat complexity and may be important modifiers of species interactions in communities. This study investigates whether the presence of habitat complexity in the form of leaf litter can alter interactions between the behaviorally dominant host ants Pheidole diversipilosa and Pheidole bicarinata, their respective specialist dipteran parasitoids (Phoridae: Apocephalus sp. 8 and Apocephalus sp. 25) and a single species of ant competitor (Dorymyrmex insanus). We used a factorial design to manipulate competition (presence/absence of competitors), mortality risk (presence/absence of parasitoids) and habitat complexity (presence/absence of leaf litter). Parasitoid presence reduced soldier caste foraging, but refuge from habitat complexity allowed increased soldier foraging in comparison to treatments in which no refuge was available. Variation in soldier foraging behavior correlated strongly with foraging success, a proxy for colony fitness. Habitat complexity allowed both host species to balance competitive success with mortality avoidance. The effect of fire on habitat complexity was also studied, and demonstrated that the immediate negative impact of fire on habitat complexity can persist for multiple years. Our findings indicate that habitat complexity can increase dominant host competitive success even in the presence of parasitoids, which may have consequences for coexistence of subordinate competitors and community diversity in general.  相似文献   

2.
Mathis WN  Sueyoshi M 《ZooKeys》2011,(114):29-40
Two new species of the genus Cyamops (Diptera: Periscelididae), the first from New Zealand, are described. The two newly described species are: Cyamops alessandrae and Cyamops crosbyi. A key to the genera of the subfamily Stenomicrinae and to the species of Cyamops from the Australasian/Oceanian Region and detailed illustrations of structures of the male terminalia are provided.  相似文献   

3.
M. A. Peirce    A. S. Cheke  R. A. Cheke 《Ibis》1977,119(4):451-461
A survey was carried out on the prevalence of blood parasites in birds in the Mascarene Islands. Smears from 357 birds of 25 species in 12 families were examined, of which 150 (42%) were found to harbour blood parasites. The most common parasites were Leucocytozoon ; a new species, L. zosteropis , is described from the Grey White-eye Zosterops borbonica mauritiana. This parasite was observed in smears from 68 birds of three species: Z. borbonica, Z. chloronothos and Z. olivacea. Other species of Leucocytozoon identified were L. fringillinarum from fodies, sparrows and a bulbul and L. marchouxi from two doves.
Haemoproteus was found only in domestic pigeons Columba livia and identified as H. columbae. Plasmodium relictum, P. vaughani and an unidentified species with elongate gametocytes were found in Zosterops , and Plasmodium sp. of low infection observed in other hosts. Trypanosoma mayae is redescribed from the House Sparrow Passer domesticus and the Mauritius Fody Foudia rubra , and considered to be a valid species. A new species of trypanosome, Trypanosoma phedinae , is described from the Malagasy Swallow Phedina b. borbonica. Other birds were found to harbour low infections of unidentified species of trypanosomes. A small number of birds were infected with Atoxoplasma , haemogregarines and Rickettsia-like organisms. An unidentified organism with a predilection for eosinophils was observed in several Mascarene Swiftlets Collocalia francica.
The results are discussed in relation to the possible effects of the parasites on the birds of the Mascarene Islands and comparisons made with the results of similar surveys on other Indian Ocean Islands.  相似文献   

4.
Within the order Mucorales (Zygomycetes), the facultative parasites Parasitella parasitica , Chaetocladium brefeldii , Chaetocladium jonesii and Absidia parricida are known to initiate biotrophic fusion parasitic interactions on a wide variety of other mucoralean hosts. Their phylogenetic relationship within the Mucorales and their ability to form parasitic structures with several known host species was examined. Together with interspecific reactions between the mycoparasites, this study found: (i) no evident differences in the spectrum of non-parasitic hosts tested within the study; (ii) A. parricida parasitises all other fusion parasites; (iii) A. parricida is ancestral to all other parasites; (iv) A. parricida is reported for the first time as phylogenetically basal to all other mucoralean fungi except the Umbelopsidaceae and (v) based on phylogenetic analyses and physiological and morphological characteristics, the slow-growing species A. parricida and Absidia zychae are removed from the genus Absidia and reclassified in the newly described genus Lentamyces .  相似文献   

5.
Madathamugadia hiepei n. sp., Splendidofilariinae, a parasite of a South African gecko Pachydactylus turneri is described together with its development obtained experimentally in Phlebotomus duboscqi (Diptera: Psychodidae: Phlebotominae). This new species differs from the two small, more highly evolved groups with a short tail and atrophied postcloacal papillae, the first group consisting of two Madagascan species, M. zonosauri and M. hopluri, parasites of the Gerrhosauridae and Iguanidae, and the second containing three species from the Ethiopian Region, M. huambensis, M. versterae and M. bissani, parasites of the Scincidae. It also differs from M. ineichi, the most primitive species of the genus (cuticularised buccal capsule, no atrophy of head papillae and largest number of precloacal papillae), a parasite of the Cordylidae in South Africa. M. hiepei is close to the two species parasitic in the Gekkonidae of the Mediterranean subregion, M. ivaschkini and M. wanjii, all three of which have a post-oesophageal vulva. However, the new species can be distinguished from the Mediterranean parasites by (a) the shorter oesophagus, (b) the number and position of the cloacal papillae and (c) the microfilaria. The three filariae of this group and M. ineichi, the only ones of which aspects of the life-cycles are known, experimentally develop in phlebotomine sand flies.  相似文献   

6.
Hymenopterous parasitoids of grass flies of the family Chloropidae from the Palaearctic and Nearctic regions are reviewed. These parasitoids belong to four superfamilies and 16 families of Hymenoptera and were reared from 39 species of Chloropidae in the Palaearctic (less than 6% of the fauna) and only from 10 species in the Nearctic Region. The majority of parasitoids are oligo-or polyphagous species. To a certain degree, the parasitoids are specialized on one of the three host groups: (1) species developing in shoots of cereal and meadow grasses; (2) forest species developing in cones of coniferous trees; and (3) species associated with the common reed, Phragmites australis. In the Palaearctic Region, the majority of parasitoids (91 species) were reared from Oscinella frit L. s. 1.; a significantly smaller number of these parasites is known from this host in the Nearctic Region, nearly half of the parasitoids being common for both regions. The next large group of parasitoids is associated with gall-inducing species of the genus Lipara Meigen (59 species) developing in the common reed. By contrast with two other groups of parasitoids, this one includes many species of the family Ichneumonidae. It should be noted that taxonomic diversity at the third trophic level is markedly greater than at the second level.  相似文献   

7.
Anilocra pilchardi n. sp. is described from several specimens collected mainly from clupeiform fishes from off Lebanon. Various stages of the parasite are considered: ovigerous and non-ovigerous females, male and intramarsupial larvae. Taxonomic comments on the relationship of A. pilchardi to other congeneric species are given. A. pilchardi belongs to a particular group of Anilocra species previously known only from the Indo-Pacific Region.  相似文献   

8.
Adults of the Argas subgenera Secretargas (3 species) and Ogadenus (1 species) were studied by scanning electron microscopy. In each species, the anterior pit and Haller's organ are situated in a large dorsal hump of Tarsus I and the 9 setae of the anterior pit are characteristic of the genus Argas in structure and numbers. In A. (S.) transgariepinus, an Ethiopian-Palearctic crevice-dwelling parasite of bats, the Haller's organ capsule roof is solid with a slitlike transverse aperture. In A. (S.) hoogstraali and A. (S.) echinops, Malagasy soil-dwelling parasites of Oplurus (Varanidae) lizards and the hedgehog-tenrec (Insectivora: Tenrecidae), respectively, the Haller's organ is virtually unroofed but partially screened by arborescent dorsal projections from the posterior wall of the capsule, and the open capsule contains numerous fine pleomorphs. In A. (O.) brumpti, a soil-dwelling parasite of the hyrax (Procavia), other terrestrial mammals, and lizards in the Ethiopian Region, the capsule is also virtually unroofed and contains numerous fine pleomorphs. The unroofed capsule is probably phylogenetically primitive and occurs only in these 3 and 2 other Argas species. The soil microhabitat (in Argas confined to 3 of the 4 species recorded here), and the reptile or ancient mammal hosts of these 3 species, as well as the zoogeographical isolation of 2 of the species in the Malagasy Region, are distinctive in this genus of 56 species. The interrelationships between an unroofed Haller's organ capsule and unusual biological properties remain to be determined.  相似文献   

9.
金道超 《昆虫学报》2001,44(2):231-234
报道了湿螨总科Hygrobatoidea, 阿土水螨科Aturidae的中国一新纪录亚科暨属及其一新种,模式标本保存于贵州大学昆虫研究所。  相似文献   

10.
Abstract. Taxonomic notes and a key are provided for the eleven species of Achrysocharoides found in Britain including A.carpini sp.n. Several forms of undetermined specific status are also described. Two species-groups are erected: the latreillii group and the aty s group. All British species have been reared as parasites only of leaf-mining larval Gracillariidae (Lepidoptera); one brood is here recorded from Caloptilia on Quercus; all other rearings are from Phyllono-rycter species. Parasite—host associations and speciation within the genus are discussed.  相似文献   

11.
Honey bee colonies are subject to numerous pathogens and parasites. Interaction among multiple pathogens and parasites is the proposed cause for Colony Collapse Disorder (CCD), a syndrome characterized by worker bees abandoning their hive. Here we provide the first documentation that the phorid fly Apocephalus borealis, previously known to parasitize bumble bees, also infects and eventually kills honey bees and may pose an emerging threat to North American apiculture. Parasitized honey bees show hive abandonment behavior, leaving their hives at night and dying shortly thereafter. On average, seven days later up to 13 phorid larvae emerge from each dead bee and pupate away from the bee. Using DNA barcoding, we confirmed that phorids that emerged from honey bees and bumble bees were the same species. Microarray analyses of honey bees from infected hives revealed that these bees are often infected with deformed wing virus and Nosema ceranae. Larvae and adult phorids also tested positive for these pathogens, implicating the fly as a potential vector or reservoir of these honey bee pathogens. Phorid parasitism may affect hive viability since 77% of sites sampled in the San Francisco Bay Area were infected by the fly and microarray analyses detected phorids in commercial hives in South Dakota and California's Central Valley. Understanding details of phorid infection may shed light on similar hive abandonment behaviors seen in CCD.  相似文献   

12.
A new species of Glypthelmins (Trematoda: Macroderoididae) is described from the intestine of Bufo marinus and Leptodactylus melanonotus from several localities of the Neotropical Region of Mexico. Glypthelmins poncedeleoni n. sp. can be differentiated from other species of the genus by having extracecally distributed vitellaria, ovary always larger than testes, and vitelline follicles grouped in 7 post-testicular, nonoverlapping, rosette-like clusters and 5 pretesticular overlapping clusters.  相似文献   

13.
1. The work reported here tested experimentally whether specialisation in Apocephalus paraponerae was due to physiological interactions that limit the parasitoid to the host ant Paraponera clavata. The suitability of other ant species as hosts was tested, and behavioural traits that may promote a high degree of specificity within this host–parasitoid system are discussed. 2. Data for development time, number of puparia, and adult eclosion success for A. paraponerae ovipositing in the regular host P. clavata are provided. A new method for testing host suitability in parasitoids of ants is described. Eggs of A. paraponerae were transferred directly into potential ant hosts. The development time, number of puparia, and adults eclosed for the eggs transferred into other ant host species are compared with comparable data from P. clavata. 3. Seven ant species within the Ponerinae are suitable for the development of A. paraponerae. The potential host range is greater than the actual host range of A. paraponerae. Flies are not limited solely by host suitability of related ant species for the development of larvae. Host location and acceptance behaviours are proposed as the primary reasons for host specialisation. The large size of the primary host P. clavata, and the ability of multiple females to raise many offspring successfully from those hosts may influence the specialisation of A. paraponerae on P. clavata.  相似文献   

14.
Infusions of Aspidosperma nitidum (Apocynaceae) wood bark are used to treat fever and malaria in the Amazon Region. Several species of this family are known to possess indole alkaloids and other classes of secondary metabolites, whereas terpenoids, an inositol and the indole alkaloids harmane-3 acid and braznitidumine have been described in A. nitidum . In the present study, extracts from the wood bark, leaves and branches of this species were prepared for assays against malaria parasites and cytotoxicity testing using human hepatoma and normal monkey kidney cells. The wood bark extracts were active against Plasmodium falciparum and showed a low cytotoxicity in vitro, whereas the leaf and branch extracts and the pure alkaloid braznitidumine were inactive. A crude methanol extract was subjected to acid-base fractionation aimed at obtaining alkaloid-rich fractions, which were active at low concentrations against P. falciparum and in mice infected with and sensitive Plasmodium berghei parasites. Our data validate the antimalarial usefulness of A. nitidum wood bark, a remedy that can most likely help to control malaria. However, the molecules responsible for this antimalarial activity have not yet been identified. Considering their high selectivity index, the alkaloid-rich fractions from the plant bark might be useful in the development of new antimalarials.  相似文献   

15.
通过对西藏夜蛾科标本的研究发现委夜蛾属2新种,墨脱委夜蛾Athetis motuoensis sp.nov.和汉密委夜蛾Athetis hanmiensis sp.nov.。文中提供西藏地区委夜蛾属的分种检索表和新种特征图及新种的详细描述。模式标本保存在东北林业大学标本室。墨脱委夜蛾,新种Athetis motuoensis sp.nov.(图1,3,5,7)本种外部形态上与条委夜蛾相似,仅前翅基部、内横线区、外横线区、外缘区和中横线暗褐色。主要区别于外生殖器上:爪形突宽短;抱器端窄而圆;抱器背延伸发达,超过抱器腹缘,末端较细;抱器内突在距抱握器基部3/4处出发,可达抱握器顶端;阳茎轭片脊部短而宽,中部平滑,下端部宽圆;囊形突较窄,略呈V形;阳茎逐渐弯曲,在末端着生有硬化的齿,龙骨稍硬化且细而长;阳茎端膜基囊中等大小,在角状突带的起始部位着生有5个长而粗大的角状突。正模雄性,西藏墨脱,海拔2100m,2005-08-24~26,黄灏、周达康、唐亮采,玻片编号HHL-1012。副模:5♂♂,3♀♀,其它采集资料同正模,雌性玻片编号HHL-1011。词源:以新种模式产地命名。汉密委夜蛾,新种Athetis hanmiensis sp.nov.(图2,4,6,8)本种外部形态上与A.suffusa(Yoshimoto,1994)相似,仅前翅红褐色明显。主要区别于外生殖器上:爪形突相对大一些;抱器端宽而平直;抱器背延伸发达,末端较细,在抱器腹缘末端伸出;抱器内突在距抱握器基部3/5处出发,可达抱握器顶端;阳茎轭片较大,脊部长而宽,中下端部宽圆;囊形突较窄,呈明显的V形;阳茎逐渐变细,龙骨硬化重且细而长;阳茎端膜基囊中等大小,具有1个小角状突,在角状突带的起始部位着生有6个长而粗大的角状突。正模雄性,西藏汉密,海拔2000m,2005-08-19~23,黄灏、周达康、唐亮采,玻片编号HHL-1017。副模:4♂♂,6♀♀,其它采集资料同正模,雌性玻片编号HHL-1016。词源:以新种模式产地命名。  相似文献   

16.
The purpose of this study was to verify the occurrence of parasitism in Atta laevigata (Smith) by phorids in Porto Nacional, Tocantins, Brazil and to evaluate some biological characteristics of those flies. From October/2002 to September/2003, at 15-day intervals, 22 samplings were carried out (149.5 +/- 82.9 workers each) comprising 3,704 ants. In the laboratory, the ants were distributed in groups of five individuals per petri dish and maintained at temperature of 25 +/- 1 masculineC and 80 +/- 5% of RH. They were fed daily with a 50% honey solution until death. The total of 106 workers (2.8%), collected with or without load (plant fragment), were parasitized by phorids: 72 workers (68%) were parasitized by Apocephalus vicosae Disney, 28 individuals (26.4%) by Neodohrniphora erthali Brown, and six (5.6%) by Apocephalus attophilus Borgmeier. The higher parasitism rates by A. vicosae (3.9-5.4%) were observed during the dry season (June-August), while the parasitism by N. erthali was lower than 2.3% throughout the year. The bigger workers were parasitized by bigger parasitoid N. erthali or by parasitoid with larger number of larvae A. attophilus. The occurrence of three phorid species in Tocantins broadens the distribution of these flies in Brazil. The development of A. vicosae larva within the thorax of the host as well as the rupture between the ant pronotum and propleuron so that the emergence of the fly can take place are characteristics not yet described on parasitism of leaf-cutting ants by phorids.  相似文献   

17.
Taeniacanthodes dojirii n. sp. (Copepoda: Poecilostomatoida: Taeniacanthidae) is described from adult female specimens collected from the body surface of Cortez electric rays Narcine entemedor (Torpediniformes, Narcinidae), captured at several locations in the Gulf of California. Taeniacanthodes dojirii is distinguished from its congeners, as well as from other members of Taeniacanthidae, by possessing unimerous fifth legs. A cladistic analysis of the 3 known species of Taeniacanthodes resulted in a single most parsimonious tree (tree length = 18 steps, consistency index = 1) demonstrating that T. gracilis and T. haakeri, both parasites of benthic teleosts, are more closely related to each other than to the new species.  相似文献   

18.
The paper reports the results of eight-year investigations on the ectoparasites of rodents and insectivores carried out in southern taiga of the Ilmen-Volkhov lowland (Novgorod Region) and Kurgolovsky reserve (Leningrad Region). Twelve species of small mammals were captured including three dominate species--bank vole Clethrionomys glareolus (2722 specimens), common shrew Sorex araneus (1658 specimens), and wood mouse Apodemus uralensis (367 specimens). Parasite community of the bank vole comprises 34 species of mites, ticks, and insects, the community of common shrew comprises 25 species, and the community of A. uralensis includes 28 species. Taxonomic diversity of the ectoparasite communities was shown to be based on the diversity of types of parasitism and ecological nishes of the host body. Permanent ectoparasites are found to be represented by 2 species of lie and 14 species of acariform mites. The group of temporary parasites includes 13 species of fleas, 10 species of gamasid mites. 3 ixodid species and 1 Trombiculidae. There is a common pool of temporary parasites of small mammals in the ecological system of taiga. Significance of different shrew and rodent species as hosts were found to be dependent on the population density in possible hosts and many other factors. Species diversity in the parasite communities of different small mammal species is dependent on the number of possible ecological nishes in the host body. Actual infill of these nishes by ectoparasites is usually lesser than potential one. Species composition of temporary parasites, their occurrence and abundance changes according to season. Interspecific competition in the temporary parasite species can decrease because of the seasonal disjunction of their population peaks. Diversification of the ecological niches of ectoparasites allow simultaneous feeding of more parasite individuals on one host, than in the case of parasitising of single species or several species with similar ecological nishes. The distribution of parasites on their hosts was also studied. The aggregative distribution has been found in ixodid larvae only, and the distribution of fleas was close to the Poisson distribution. Deviations from the aggregative distribution can be an effect of several independent factors, including limited ability of small mammals for providing numerous parasites with food. On the most part of hosts simultaneous parasitizing of no more than 1-3 individuals of each tick, mite, and flea species was registered. Excessive infestation by ectoparasites may probably be limited by effective reactions of self-purification in the mammal hosts.  相似文献   

19.
20.
以种类名录报道广东鼎湖山自然保护区的土壤甲螨58种,并记述新种巨杆棱甲螨Mochlozetes grandis sp.nov.此外还对该地区甲螨区系的特点作了初步分析。  相似文献   

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