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1092. A reverse viewpoint on the upper semicontinuity of multivalued maps

Creator:
Fenille, Marcio Colombo
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
multivalued map, power set, upper semicontinuity, and upper semifinite topology
Language:
English
Description:
For a multivalued map ϕ: Y ⊸ (X, τ ) between topological spaces, the upper semifinite topology A(τ ) on the power set A(X) = {A ⊂ X : A ≠ ∅} is such that ϕ is upper semicontinuous if and only if it is continuous when viewed as a singlevalued map ϕ: Y → (A(X), A(τ )). In this paper, we seek a result like this from a reverse viewpoint, namely, given a set X and a topology Γ on A(X), we consider a natural topology R(Γ) on X, constructed from Γ satisfying R(Γ) = τ if Γ = A(τ ), and we give necessary and sufficient conditions to the upper semicontinuity of a multivalued map ϕ: Y ⊸ (X, R(Γ)) to be equivalent to the continuity of the singlevalued map ϕ: Y → (A(X), Γ).
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1093. A review of Dendromonocotyle (Monogenea: Monocotylidae) from the skin of stingrays and their control in public aquaria

Creator:
Chisholm, Leslie A., Whittington, Ian D., and Fischer, Andreas B. P.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Monogenea, Monocotylidae, Dendromonocotyle, aquaria, Dasyatidae, and Taeniura meyeni
Language:
English
Description:
Dendromonocotyle species (Monogenea: Monocotylidae) are the only monocotylids to parasitize the skin of chondrichthyan hosts. Currently 11 species are recorded from the skin of ray species in the Dasyatidae, Myliobatidae and Urolophidae. There have been increasing reports of Dendromonocotyle outbreaks on rays kept in public aquaria. This paper provides a broad review of Dendromonocotyle that should assist taxonomists and aquarists with species identification and help decisions on potential control methods for Dendromonocotyle infections. The taxonomy and host-specificity of Dendromonocotyle are discussed and a key to current species is provided. We summarise what little is known about the biology of Dendromonocotyle including egg embryonation and hatching, feeding, camouflage and reproduction. The efficacy of freshwater baths, chemical treatments and biological control measures such as the use of cleaner fish for Dendromonocotyle is also discussed. We demonstrate that effective control of Dendromonocotyle on captive rays is hampered by the lack of basic biological data on the life cycle of the parasites. A case history is provided outlining the success of a public aquarium (Underwater World, Mooloolaba, Queensland, Australia) in managing D. pipinna infections on captive Taeniura meyeni without chemical intervention simply by taking measures to reduce host stress.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1094. A review of Fennoscandian arthropods living on and in snow

Creator:
Hagvar, Sigmund
Type:
article, model:article, and TEXT
Subject:
Arthropods, winter activity, snow, adaptations, migration, orientation, Fennoscandia, review, Diptera, Hypogastura, Chionea, Trichocera, Mecoptera, Boreus, Araneae, Bolephthyphantes, subnivean, intranivean, and supranivean
Language:
English
Description:
A permanent snow cover for several months is typical for large parts of Norway, Sweden and Finland. Snow layers thicker than about 20 cm insulate the soil surface and stabilize the ground temperature close to 0°C. Many ground-living invertebrates are active at this temperature in the subnivean air space. From this "base camp", some invertebrates migrate upwards to use the snow as a substrate. The intranivean fauna consists of springtails (Collembola) and mites (Acari) that are small enough to move within the narrow pores between snow crystals. The supranivean fauna consists of various invertebrates that are active on the snow surface. Some of them are Collembola that have migrated through the snow layers. However, most of them are larger insects and spiders which migrate between the subnivean and supranivean habitats following air channels which are naturally created along tree stems, bushes etc. penetrating the snow. Likewise, certain Chironomidae and Plecoptera, hatching from winter-open rivers and brooks, are active on the snow surface. The supranivean arthropod fauna has the following characteristics: 1. It is a weather dependent assemblage of species, coming and going with changes in air temperature, cloud cover, and wind. Below ca. -6°C animals are absent, but at temperatures around or above zero, many groups can be simultaneously active on snow. 2. The snow surface fauna shows phenological changes throughout the winter, as certain species and groups are mainly active during certain months. 3. Some invertebrates are highly specialized and take advantage of the snow surface as an arena in their life cycle. Examples are Hypogastrura socialis (Collembola), and the two wingless insects Chionea sp. (Diptera: Limoniidae) and Boreus sp. (Mecoptera). They use the smooth snow surface for efficient migration. Chionea sp. and Boreus sp. lay their eggs during the snow-covered period, while H. socialis migrates to create new colonies. The cold tolerant spider Bolephthyphantes index is unique in constructing webs in small depressions on the snow, to catch migrating Collembola. Various adaptations for using the snow as a substrate are discussed. Besides physiological and morphological adaptations, snow surface arthropods show special behavioural adaptations. Most conspicuous is the ability of several Collembola species to navigate during migration, using the position of the sun for orientation. Furthermore, in Collembola and Mecoptera, jumping as an original mechanism to escape predators has independently evolved into a migrating mechanism. An evolutionary potential exists for more invertebrate groups to take advantage of snow as a substrate in their life cycle. For instance, several more cold tolerant spiders might evolve the ability to catch migrating Collembola on snow.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1095. A review of Palaearctic Gymnophora Macquart (Diptera: Phoridae), with description of new species

Creator:
Mostovski, Mikhail B. and Mikhailovskaya, Marina V.
Type:
article, model:article, and TEXT
Subject:
Taxonomy, Phoridae, Gymnophora, Palaearctic, new species, new synonymy, lectotypes, and distribution
Language:
English
Description:
Palaearctic species of the genus Gymnophora are reviewed. Four new species, G. amurensis sp. n., G. gornostaevi sp. n., G. perpropinqua sp. n., and G. victoria sp. n., are described from the European Russia, Middle Asia, and Russian Far East. Females of two other species from the Far East are described under code letters. G. laciniata Michailovskaya, 1997 is synonymised under G. prescherweberae Disney, 1997. Lectotypes of G. arcuata (Meigen, 1839) and G. verrucata (Schmitz, 1929) are designated. The latter species is redescribed. Palaearctic females of G. nigripennis demonstrate wide variation of taxonomically important features and may, in fact, represent a group of closely related species. One female of G. nigripennis, which has been caught alive, is recorded to be infected with fungi.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1096. A review of picobiine mites (Acari: Syringophilidae: Picobiinae) parasitising African birds

Creator:
Skoracki, Maciej and Hromada, Martin
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
ectoparasites, taxonomy, quill mites, Lawrencipicobia, and Gunabopicobia
Language:
English
Description:
A fauna of quill mites of the subfamily Picobiinae (Acari: Syringophilidae) associated with African birds is revised. Two new monotypic genera are proposed, Gunabopicobia gen. n. for Picobia zumpti Lawrence, 1959 and Lawrencipicobia gen. n. for Picobia poicephali Skoracki et Dabert, 2002. These new genera differ from other genera of the subfamily by the following features: in females of Gunabopicobia, propodonotal setae vi are situated anterior to the level of setae ve; the narrow lateral propodonotal shields bear bases of setae vi, ve, si and se; the bases of setae 1a-1a are coalesced; the genital setae and the opisthosomal lobes are absent; the leg I with full set of solenidia and apodemes I are devoid of the thorn-like protuberances in the middle part. In females of Lawrencipicobia, the bases of setae 1a-1a are not coalesced; the propodonotal shield is entire; the genital setae are present; legs I are with full set of solenidia. Additionally, two new species belonging to Picobia Haller, 1878 are described, Picobia illadopsae sp. n. parasitising Illadopsis rufipennis (Sharpe) (Passeriformes: Pellorneidae) in Kenya and Picobia phoenicuri sp. n. infecting Phoenicurus moussieri (Olphe-Galliard) in Tunisia. The following species are redescribed, Columbiphilus alectoris (Fain, Bochkov et Mironov, 2000), Lawrencipicobia poicephali (Skoracki et Dabert, 2001) comb. n. and Picobia phoeniculi (Fain, Bochkov et Mironov, 2000). The key to the genera of the Picobiinae is provided.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1098. A review of spotted hyaena population estimates highlights the need for greater utilisation of spatial capture-recapture methods

Creator:
Davis, Robert S., Gentle, Louise K., Stone, Emma L., Uzal, Antonio, and Yarnell, Richard W.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
call-in survey, density, population monitoring, survey methods, and track counts
Language:
English
Description:
As apex predators with a regulating effect on interspecific competitors and prey demographics, monitoring of spotted hyaena (Crocuta crocuta) population trends can provide a reliable indicator of ecosystem health. However, the ability of current survey techniques to monitor carnivore densities effectively are increasingly questioned. This has led recent studies to advocate increased application of spatial capture-recapture (SCR) methods to estimate population density for large carnivores. We reviewed the literature regarding methods used to estimate population density for spotted hyaena since 2000. Our review found that SCR methods are underutilised for estimating spotted hyaena density, with only eight published studies (13% of articles assessed) using an SCR approach. Call-in surveys were the most frequently used method, featuring in 47% of studies. However, 63% of studies that used call-in surveys could not estimate a site-specific calibration index. The calibration index estimates the distance and rate at which the focal species responds to audio lures and, as response rates are impacted by site-specific ecological and environmental factors, studies that could not calibrate this index are likely inaccurate. Further application of SCR techniques will allow more robust estimation of spotted hyaena density, reducing uncertainty and potential overestimation that limit inference from existing survey methods.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1099. A review of taxonomy and flower-breeding ecology of the Colocasiomyia toshiokai species group (Diptera: Drosophilidae), with description of a new species from Indonesia

Creator:
Shi, Tao , Toda, Masanori J. , Takano, Kohei Takenaka, Yafuso, Masako , Suwito, Awit , Wong, Sin Yeng, Shang, Su-Qin , and Gao, Jian-Jun
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
Diptera, Drosophilidae, Colocasiomyia toshiokai species group, DNA barcoding, species delimitation, taxonomy, Araceae, Homalomena, Aglaonema, flower-breeding ecology, Malaysia, and Indonesia
Language:
English
Description:
Flies of the Colocasiomyia toshiokai species group depend exclusively on inflorescences/infructescences of the aroid tribe Homalomeneae. The taxonomy and reproductive biology of this group is reviewed on the basis of data and samples collected from Southeast Asia. The species boundaries are determined by combining morphological analyses and molecular species delimitation based on sequences of the mitochondrial COI (cytochrome c oxidase subunit I) gene. For the phylogenetic classification within this species group, a cladistic analysis of all the member species is conducted based on 29 parsimony-informative, morphological characters. As a result, six species are recognised within the toshiokai group, including one new species, viz. C. toshiokai, C. xanthogaster, C. nigricauda, C. erythrocephala, C. heterodonta and C. rostrata sp. n. Various host plants are utilised by these species in different combinations at different localities: Some host plants are monopolized by a single species, while others are shared by two or three species. C. xanthogaster and C. heterodonta cohabit on the same host plant in West Java, breeding on spatially different parts of the spadix. There is a close synchrony between flower-visiting behaviour of flies and flowering events of host plants, which indicate an intimate pollination mutualism.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1100. A review of the currently recognised zoogonid cercariae, including the identification and emergence ecology of Cercaria capricornia XI (Digenea: Zoogonidae) from Nassarius olivaceus (Gastropoda: Nassariidae) in Central Queensland, Australia

Creator:
Barnett, Leonie J., Miller, Terrence L., and Cribb, Thomas H.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Capricornia, ITS2, Trematoda, internal transcribed spacer 2, and Platyhelminthes
Language:
English
Description:
In the present study, we review the known zoogonid cercariae, summarise their life-cycles and first intermediate host distributions, and present a new cercaria, Cercaria capricornia XI (Digenea: Zoogonidae), which was found in one of three nassariid gastropods, Nassarius olivaceus (Bruguière), surveyed in the intertidal zone in the Capricornia region of Central Queensland, Australia. Morphological data and molecular analysis of the ITS2 rDNA region support placement of this cercaria in the family Zoogonidae but do not allow any further resolution of its identity. There are now fifteen cercariae described as belonging to the Zoogonidae; thirteen of these, including the present species, infect neogastropods as first intermediate hosts and two use vetigastropods. This study reinforces the pattern that the Nassariidae is by far the most commonly reported family for the Zoogonidae. Given its richness we predict that the Nassariidae will prove to harbour many more zoogonid species.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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