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《Journal of Natural History》2012,46(37-40):2425-2451
A century ago Bürger described the species Drepanophorus valdiviae from a single specimen taken from 155 m off the southern tip of Africa by the research vessel Valdivia during the German Deep Sea Expedition. Stiasny-Wijnhoff in 1923 Stiasny-Wijnhoff, G. 1923. On Brinkmann's system of the Nemertea Enopla and Siboganemertes weberi n. g. n. sp. Q J Microsc Sci., 67: 627669.  [Google Scholar] transferred this species along with Amphiporus stannii (sensu Bürger 1895 Bürger, O. 1895. Die Nemertinen des Golfes von Neapel und der angrenzenden Meeres-Abschnitte. Fauna und Flora des Golfes von Neapel, 22: 1743.  [Google Scholar]) to a new genus Valdivianemertes but did not mention a family affiliation. In 1993 Crandall transferred this genus to the family Cratenemertidae. During the Spanish Antarctic Expedition BENTART 2003, carried out on board the RV Hespérides, we found one specimen identified with certainty as Valdivianemertes valdiviae, at 602 m depth in the Bellingshausen Sea (Antarctica). As there is no extant holotype, we here redescribe this species from this new specimen and designate it the neotype of this species; photomicrographs of the different regions of the body and the proboscis structure are provided for the first time.  相似文献   

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《Journal of Natural History》2012,46(41-44):2551-2567
In the framework of the international project called “Conservation and Sustainable Management of Below‐Ground Biodiversity”, soil macrofauna collections were carried out in the Centre‐West Ivory Coast. Altogether, 13 earthworm species were recorded, of which four belonged to the family Eudrilidae and nine to the family Acanthodrilidae. From the species collected, two, Dichogaster (Dichogaster) eburnea sp. nov. and Dichogaster (Dichogaster) mamillata sp. nov., proved to be new to science. To accommodate the enigmatic eudrilid earthworm species Scolecillus compositus Omodeo, 1958 Omodeo, P. 1958. Oligochetes. In, La reserve naturelle integrale du Mont Nimba.. Memoire de la Institut Francais Afrique Noire, 53: 9109.  [Google Scholar], a new genus, Lavellea gen. nov., is proposed.  相似文献   

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The brown bear (Ursus arctos) in Greece is considered endangered but little is known about the genetic status and the exact size of local populations. Non-invasive genetic sampling was used in this study to investigate the genetic diversity and genetic structure of the brown bear population in the Kastoria region (northwest Macedonia, Greece) and to estimate its population size. Estimation of demographic parameters was based on innovative, well-evaluated methods that can provide estimates from a single sampling session. DNA was extracted from hairs, scat and blood samples and subsequent amplification of 10 microsatellite loci allowed the identification of a minimum number of 75 living bears in the study area while the mark–recapture-based analysis resulted in a point estimation of 219 individuals. Relatively high diversity values, lack of heterozygosity deficiency as well as estimated effective population size, support the Kastoria bear population having good conservation status.  相似文献   

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A new introduced species, Otala punctata (Müller, 1774) and new records in Chile for Cornu aspersum (Müller, 1774) and Deroceras laeve (Müller, 1774) are documented based on surveys carried out in northern and central areas of the country. The presence and distribution of these alien species are complemented with a comprehensive compilation of all 34 non-indigenous species of marine, freshwater and terrestrial Mollusca in Chile; until 1999, only 16 alien species were known in Chile. Most of these alien species are found exclusively in transformed habitats, few exist in natural environments. The mechanism of introduction for the majority of these non-indigenous species is unknown; however, horticultural development, urban and suburban transformation of original natural habitats, and the aquarium trade are the most likely pathways of introduction. The highest threat of alien species is direct competition and predation of native molluscs, especially the small native land gastropods. Education and continuous field surveys are vital to detect and prevent their propagation as well as to avoid introduction of additional alien taxa.  相似文献   

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《Journal of Natural History》2012,46(7-8):465-479
This study compares the diets of the giant otter and the Neotropical otter, two Lutrinae species which feed mainly on fish. The study was carried out through the analyses of faecal samples collected between 2006 and 2008 (82 giant otter and 75 Neotropical otter) in the Jaú National Park. The giant otter feeds mainly on Cichlidae, Erythrinidae and Characidae, while the Neotropical otter consumes Doradidae, Loricariidae and Cichlidae. The two otter species had low diet similarity (Pianka’s Index = 0.16). The giant otter consumed larger fish than the Neotropical otter, which probably explores shallow river parts in search of small catfish. Prey other than fish were more frequent in the diet of the Neotropical otter, whereas giant otters ate a greater diversity of fish families. Increasing knowledge of the feeding habits and interactions of these two top-order predators is vital to determine appropriate protection and management policies.  相似文献   

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《Journal of Natural History》2012,46(25):2339-2354
The parasitoid complex of spiders was studied in three different sites of a forest and, for comparison, in open habitats in north‐western Lower Saxony (Germany). Qualitative data and, for four spider species, detailed quantitative rearing data were obtained. At least 25 parasitoids of spiders were recorded (23 species of Hymenoptera and two species of Diptera). External parasitoids of spiders were rare in the woodlands; only up to 1% of the spiders collected by hand searching and sweep netting had ectoparasitoids. During the investigation 23 parasitoid species were reared from spider egg masses, 10 of them occurring in woodlands. Two species were secondary parasitoids. Several parasitoid–host relationships were recorded for the first time. Egg masses of Floronia bucculenta were parasitized up to 5% by two species of the genus Gelis. Up to 10% of the egg masses of Linyphia hortensis were parasitized by Aclastus species. Egg masses of the spider genus Ero were parasitized by three species, causing an overall mortality of 40%. For egg masses of Agroeca spp. parasitization at some locations was up to 60%. An overview of the Central European parasitoid complex of spiders is provided.  相似文献   

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《Journal of Natural History》2012,46(19-20):1421-1434
We studied a population of Crossodactylus bokermanni in a stream at the Reserva Particular do Patrimônio Natural, Santuário do Caraça, south‐eastern Brazil, with respect to microhabitat use and diet. We characterized microhabitats based on substrate, distance to water and exposure level of the occupying individual (exposed or sheltered), and adjacent aquatic microhabitats (evaluated as potential nesting sites based on observed nests), according to water current (absent, slow or fast), substrate and depth. Calling males, silent males, ovigerous females, non‐ovigerous females and juveniles showed spatial niche overlap higher than that expected by chance, with calling males showing the strongest preference for microhabitats close to potential nesting sites (with intermediate depths, fast current and sandy bottom). Only 14 males out of 48 individuals examined for stomach contents had prey in their stomachs. The food items with the highest electivity values were Coleoptera and Diptera, but preys with both high and low mobility were exploited.  相似文献   

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There are no published studies on the diet of Mogollon voles ( Microtus mogollonensis ) although this species occurs throughout the Southwest in montane forestlands. Mogollon voles are believed to be herbivorous, selecting the vegetative portion of grass as their dominant food source. Herbivores frequently select more easily digested C 3 plants over C 4 plants; we thus expected Mogollon voles would feed primarily on C 3 plants. We collected hair samples from Mogollon voles captured in northern Arizona between 1967 and 2003 and plant samples from some capture sites. Then we compared stable carbon (δ 13 C) and nitrogen (δ 15 N) isotope ratios to investigate dietary preferences for C 3 or C 4 plants. Mean isotope ratios for C 3 plants we sampled were –26.84‰ ( s = 0.17) for δ 13 C and –0.02‰ ( s = 0.32) for δ 15 N. For C 4 plants, mean isotope ratios for δ 13 C and δ 15 N were –15.04 ‰ ( s = 0.38) and –0.74‰ ( s = 0.55), respectively. Mogollon voles were largely herbivorous based on δ 15 N (mean and standard error: 3.77 ± 0.17‰) and used C 3 plants more than C 4 based on δ 13 C (–24.21 ± 0.14‰). Activities that lead to changes in plant species composition or reduction in C 3 plants in montane grasslands and forests (e.g., excessive ungulate grazing) may reduce habitat quality for Mogollon voles.  相似文献   

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A recently published paper on some Helix species from the East Mediterranean basin is briefly reviewed. Parts of the results of the authors of that study are erroneous because they are based on a misinterpretation of some of the taxa involved. An analysis of the actually studied taxa is presented, and the essential consequences for nomenclature and phylogeny are discussed.  相似文献   

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Ecological data directly from the field are important in understanding the life history strategies of kinosternid species in the tropics. Herein we summarize the basic population ecology and life history of Kinosternon integrum in the municipality of Tonatico (southeastern Estado de México, México). From October 2003 to November 2004, we marked a total of 204 turtles and recaptured 118 of them. Mean population size using the Jolly-Seber model was 197 (95% CI 128–416) individuals, with a sex ratio of 1:1.7, biased to females. Males were larger than females in carapace length and plastron length. The reproductive season starts in late June and finishes in late October. The smallest female with oviductal eggs was 122 mm in carapace length. Mean clutch size was 4 eggs ( s = 1.77, range 1–8) and was significantly and positively related to body size. Mean egg length was 30.43 mm ( s = 2.24, range 23.92–35.96), mean width was 16.35 mm ( s = 1.01, range 12.99–18.30), and mean weight was 5.14 g ( s = 0.60, range 3.41–6.57). Mean egg length was significantly and inversely related to clutch size. Relative clutch mass (reproductive effort) was 0.043 ( s = 0.017, range 0.017–0.071), which is the smallest value reported for the genus Kinosternon. Additionally, there was no evidence of a pelvic restriction on egg size in this population. This is the first study that documents basic population ecology and reproductive characteristics for a single population of the most widespread freshwater turtle in Mexico.  相似文献   

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This paper presents the results of a study performed in eight caves located in the area of the Kraków-Cz?stochowa Upland. In total, 586 samples (400 cm3 each) were taken from the caves and sites located up to one metre from the main entrances of the caves. Of 109 species belonging to 13 families that were identified, four were species new for Polish fauna. In this study, cluster analysis and correspondence analysis were used to compare the species composition of mite communities living in the caves and their immediate surroundings. We also examined the possibility of isolating troglophilic species based on IndVal analysis. Those results showed distinct differences between Gamasina mites living in two distinct habitats. We also established indicator species for the examined caves.  相似文献   

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《Journal of Natural History》2012,46(39-40):2573-2590
ABSTRACT

Biotic or abiotic factors responsible for temporal or spatial variation in metazoan parasite communities of the green jack Caranx caballus were studied over a nine-year period using samples collected at locations along the south-central Pacific coast of Mexico. A total of 708 fish were collected from six locations between December 2009 and October 2017. Thirty-two parasite species were identified: three Monogenea, nine Digenea, two Cestoda, five Nematoda, eight Copepoda, and three Isopoda. At the component community level, parasite species richness varied significantly from seven (Zihuatanejo 2016) to 18 (Acapulco Bay 2011). The component communities and infracommunities of C. caballus exhibited a similar pattern: low species numbers, low diversity, and dominance by a single species (mainly the monogenean Pseudomazocraes selene or the digenean Bucephalus varicus). Parasite community structure and species composition varied between locations and/or sampling years. The main factors responsible for these variations were host traits such as feeding behaviour and body size, the occurrence of a set of distinctive parasite species, and possible variations in the availability of infected prey between locations.  相似文献   

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