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1.
Cheilostomatous Bryozoa from Vanuatu   总被引:1,自引:0,他引:1  
The present account of some Bryozoa from Vanuatu is the first study of reef-flat species from the eastern Coral Sea. Based on samples collected from several shallow water localities on the island of Efate, a total of 92 species is described, including a new family, three new genera and 20 new species. Some of the newly recognized species are the result of taxonomic revision stimulated by these new samples, while others are entirely new to science. Of the new taxa described here, 16 are presently known only from Vanuatu. The total number of species recorded does not accurately represent the true taxonomic diversity of the Cheilostomatida of Vanuatu, and further sampling, at other localities and in other habitats, is needed before it can be reasonably estimated. The fauna is predominantly Indo-West Pacific in character with a high proportion of species apparently known only in the Southwest Pacific.  相似文献   

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Social bees generally host fewer nest invaders than do ants and termites. This is potentially explained by the adaptive defensive strategies of host bees when faced with nest invaders exhibiting various levels of colony integration (based on adaptations to the nest habitat and frequency of nest inhabitation). In the present study, experiments are performed to determine the behaviour at the nest entrance of European honeybee guards Apis mellifera L. (Hymenoptera: Apidae) toward beetle invaders of various levels of behavioural integration into colonies. The species used to test this include Aethina tumida Murray (Coleoptera: Nitidulidae), which is regarded as a highly integrated, unwelcome guest (synechthran) or true guest (symphile); Lobiopa insularis Laporte (Coleoptera: Nitidulidae) and Epuraea luteola Erichson (Coleoptera: Nitidulidae) that are accidentals; and Carpophilus humeralis Fabricius (Coleoptera: Nitidulidae), Carpophilus hemipterus L. (Coleoptera: Nitidulidae) and Tribolium castaneum Herbst (Coleoptera: Tenebrionidae), all of which are species that are not integrated into honeybee colonies. The responses of guard bees to a control bead also are noted. In general, bees ignore T. castaneum and E. luteola to a greater extent than other beetle species. Bees make contact with the black glass bead (a non‐aggressive behaviour) more than they do all beetle species. Bees treat A. tumida more defensively than they treat any other beetle species and the level of bee defensiveness varies by colony. These data suggest an adaptive heightened defensive response by bees toward the most integrated colony intruder but a significantly reduced level of response toward invaders representing all other levels of colony integration.  相似文献   

4.
Ichthyological Research - A new species of the genus Acropoma, A. musorstom sp. nov. is described based on four specimens (126.3–143.0 mm in standard length: SL) collected from Vanuatu and...  相似文献   

5.
Two new species of Vellozia from the Espinhaco range in the State of Minas Gerais, Brazil, are described and their taxonomic relationships are considered. A discussion of their geographical distribution and an account of their leaf anatomy is provided.  相似文献   

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Abstract:  Deltamethrin is a commonly used insecticide for controlling its key maize pest, the fall armyworm Spodoptera frugiperda (Lep., Noctuidae). Its toxicological profile is well known, but its impact on arthropods widely reported as bioindicators, mainly springtails (Collembola) and mites (Oribatida), is yet to be assessed in tropical maize fields. The treatments used to circumvent this shortcoming were conventional cultivation and no-tillage cultivation (with a pre-sowing application of 2,4-D and glyphosate) systems with or without deltamethrin spraying. The deltamethrin residue analysis of soil samples by gas chromatography did not detect the insecticide 24 h after it was sprayed on the maize fields. There was no significant overall effect of deltamethrin based on principal component analysis. However, repeated-measures analyses of variance detected significant impact of deltamethrin in a species of Nitidulidae (Coleoptera). The cultivation system also provided significant impact on Oribatida and Gamasida soil mites and on the same Nitidulidae species referred above, which were more abundant in the conventional cultivation system. Springtails were also significantly affected by the cultivation system showing greater abundance in the conventional system, except Podumorpha. Analyses using only high taxonomic levels did not allow the detection of impact in the ant assemblage assessed. The results suggest that the impact of deltamethrin on soil arthropods from tropical fields varies among species and is lower than expected. The cultivation system imposes more drastic effects on arthropod assemblage.  相似文献   

8.
Otolith shape analysis has been used in a number of studies as an inexpensive and powerful method for categorising fish in individual stocks. Elliptical Fourier analysis was used on three different amphidromous Sicyopterus species. Sicyopterus lagocephalus is a widespread species while the other two have a limited distribution area, Sicyopterus aiensis being endemic to Vanuatu, and Sicyopterus sarasini to New Caledonia. Both endemics live in sympatry with the widespread species. The otolith shape of all fish sampled was a clear species differentiator, thereby demonstrating that otolith shape is species-specific. At an intraspecific level there are different river populations within samples from Vanuatu, indicating a western group and an eastern “central” group.These results are congruent both for the endemic species, S. aiensis and for the cosmopolitan species. Finally, we found that, for S. lagocephalus, the cosmopolitan species, New Caledonian samples are close to western Vanuatu samples, the latter two being well differentiated from the eastern “central” Vanuatu samples. The explanation for these results may lay either in the influence of environmental factors on the otolith shape, or in the influence of common early life history thus reflecting genetic factors, or a combination of both.  相似文献   

9.
We examined variation in mitochondrial control region (Domain I) sequences in three distantly related species of birds found on multiple islands in Vanuatu: the Buff-banded Rail Gallirallus philippensis (n=21, 433bp), the Emerald Dove Chalcophaps indica (n=21, 513bp), and the Streaked Fantail Rhipidura spilodera (n=17, 326bp). Nucleotide and haplotype diversity were similar in all three species and showed little to no geographic structure within Vanuatu. Estimates of demographic parameters, tests for excess rare alleles, and the structure of both haplotype networks and pairwise mismatch distributions support a hypothesis of recent colonization and subsequent expansion in C. indica and R. spilodera but not in G. philippensis. Phylogenetic analyses suggest that G. philippensis samples from Vanuatu are polyphyletic, and further indicate that this species has had a more complex history of colonization than do the other two species. Estimated divergence times of alleles sampled in Vanuatu suggest there may be slight differences among species in the timing of colonization of Vanuatu despite differences in flight ability and presumed dispersal ability. In all three species, current populations probably derive from colonists that arrived several million years after the islands formed. Our comparisons illustrate the potential of direct genetic analyses of to highlight historical differences among co-distributed species with similar levels of phenotypic variation.  相似文献   

10.
During expeditions to Santo and the Torres islands belonging to the Vanuatu archipelago in 2006 and 2007, ten new species of tateid gastropods confined to springs, the upper most, slowly flowing regions of streams or the groundwater had been discovered. These species were now described based on shell morphology and anatomy. In accordance with geography, these characters placed the species from Vanuatu between those from New Caledonia and Fiji, suggesting a stepping stone-like dispersal across the Pacific with an origin in New Zealand and the far end on the Austral islands. We also assessed the threat status of the new species according to the IUCN Red List criteria and concluded that they should be amended by explicit incorporation of the scale of potential human impact or stochastic natural events relative to the size of the habitat of organisms.  相似文献   

11.
A key is provided to the New World genera of Thripidae with nine-segmented antennae. Psydrothrips kewi gen. et sp. nov. is described, a discussion is given of the morphology of the Neotropical genera which it resembles, and keys to species are provided.  相似文献   

12.
A new species belonging to the Dothideomycete genus Acanthostigma is described from bark of two Nothofagus species from Argentina. Its identity as a new species is based on both morphology and molecular sequence data. Acanthostigma patagonica differs from other species in the genus by having larger ascomata and setae and wider, asymmetrical ascospores. An amended key to Acanthostigma species is provided along with a discussion of other species previously described from South America.  相似文献   

13.
Abstract. The genus Bitheca is described for a distinctive clade of small Limosininae whose range extends from Canada south to Ecuador. The following twelve species are described as new: agarica, boleta, caballa, dispar, ejuncida, fundata, grossa, horrida, involuta, jubilata, kappa and lambda. A key to the species of Bitheca is provided and their phylogeny is discussed. Pterogramma steyskali Deeming and Minilimosina masoni Marshall are moved into the genus Bitheca. A cladogram is provided and its derivation explained in detail, with a discussion of the use of character weighting in cladistics.  相似文献   

14.
Euglossa williamsisp. n. is here described from the lowland Amazonian region in Ecuador and Peru, and as part of a small species assemblage within Euglossa consisting of Euglossa dodsoni Moure and Euglossa obtusa Dressler. An identification key to the males of the group is provided plus detailed figures of the new species and representative illustrations for the others. A brief discussion of the taxonomic and biogeographical implications of the new species is provided. New records in Honduras and Nicaragua are provided for the related Euglossa dodsoni.  相似文献   

15.
A review of the Afrotropical genus Stephanospathius Belokobylskij is provided. A new species Stephanospathius benoitisp. n. from the Republic of Congo, and the male and, for the first time, the female of Stephanospathius ornatipes (Kieffer) are described. A discussion of the status and composition of the tribe Stephaniscini is given and a new name for this tribe, Leptospathiini, nom. n., is proposed. A key to the included genera and a key to species of Stephanospathius are provided.  相似文献   

16.
Aethina tumida Murray (Coleoptera: Nitidulidae) is an invasive parasite species in populations of honey bees, Apis mellifera L. Aiming toward substitution of chemical control, we here identified a naturally occurring fungal pathogen of adult A. tumida from its endemic range in South Africa [Metarhizium anisopliae (Metschnikoff) Sorokin variety anisopliae strain FI-203]. The susceptibility of adult beetles (n = 400) to this fungus and to three other generalist entomopathogenic fungal isolates [Metarhizium anisopliae, Beauveria bassiana (Balsamo) Vuillemin, and Hirsutella illustris Minter & Brady] was assessed using spore suspension bioassays. The data revealed significantly increased mortality in the B. bassiana (74.00 +/- 8.94%) and M. anisopliae variety anisopliae (28.00 +/- 16.43%) tests but not in the H. illustris (2.00 +/- 4.47%) and M. anisopliae (12.00 +/- 8.37%) groups. The results indicate a potential for entomopathogenic fungi as an alternative control of A. tumida.  相似文献   

17.
Firewood can serve as a vector in the transport of non-native species, including wood-boring insects that feed within the wood and thus can be transported accidentally. Governments have enacted limitations on the movement of firewood in an effort to limit the anthropogenic movement of non-native species through, for example, recreational camping. Although the movement of invasive species through firewood is a documented invasion pathway, it is not trivial for governments to determine a "safe" allowable distance for moving firewood. We were motivated by this challenge and developed a theoretical simulation to determine the campgrounds that could be potentially exposed to infested firewood based upon the hypothetical distribution of an invasive species and the allowable distance for moving firewood. We extend this concept to the known distributions of emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) and Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) Coleoptera: Cerambycidae). We illustrate, based upon theoretical and empirical observations, that as the distribution of an invasive species increases, more rigid constraints on the movement of firewood would be required relative to those species that are distributed over a smaller scale. Also, on the level of management within a state, smaller states have far less margin for error than larger ones, as even extremely rigid restrictions on the movement of firewood could have little management effect unless the infested area is spatially limited. These results collectively suggest the potential for a dynamic management strategy that adjusts allowable distances for firewood movement based upon the distribution of the non-native species.  相似文献   

18.
Emerging pathogens are a growing threat to human health, agriculture and the diversity of ecological communities but may also help control problematic species. Here we investigated the diversity, distribution and consequences of emerging fungal pathogens infecting an aggressive invasive grass that is rapidly colonising habitats throughout the eastern USA. We document the recent emergence and accumulation over time of diverse pathogens that are members of a single fungal genus and represent multiple, recently described or undescribed species. We also show that experimental suppression of these pathogens increased host performance in the field, demonstrating the negative effects of emerging pathogens on invasive plants. Our results suggest that invasive species can facilitate pathogen emergence and amplification, raising concerns about movement of pathogens among agricultural, horticultural, and wild grasses. However, one possible benefit of pathogen accumulation is suppression of aggressive invaders over the long term, potentially abating their negative impacts on native communities.  相似文献   

19.
One island group suggested to be an exception to the species–area Relationship is the Vanuatu Archipelago, a group of 13 large and 80 small islands in the southwest Pacific Ocean. To test the hypothesis that the lizard fauna of the Vanuatu Archipelago does not meet the predictions of the species-area relationship, and thus is depauperate, we compare diversity among several island groups in the southwest Pacific: Fiji, the Loyalty Islands, New Caledonia, Samoa, the Solomon Islands, Tonga, and Vanuatu. We found that the lizard diversity of Vanuatu meets the pattern of diversity predicted by the species-area relationship. The Solomon Islands, the largest and least isolated oceanic archipelago considered, has the greatest species diversity and endemism of the oceanic islands. Inclusion or exclusion of island groups based on factors such as geologic history or faunal source affects the strength of the relationship between diversity, area, and history of emergence, and influences perceptions of diversity within individual archipelagos. In addition to island size, factors such evolutionary time scale, speciation, and archipelago complexity influence species richness on islands.  相似文献   

20.
Cochemiea pondii subsp. maritima is illustrated, the species and all three subspecies described, each provided with a full synonymy, statements on distribution, habitat and ecology, etymology, phenology, and conservation status. A commentary is given on the re‐acceptance of Cochemiea, separated from Mammillaria. Cultivation notes are provided; the species, and in particular subspecies maritima, is far from common in cultivation and not widely available. The discussion covers aspects of recognition of the subspecies, type collections, related taxa, and comments on the addition of several more species to the genus by Doweld.  相似文献   

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