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1.
Pathogen-mediated changes in host behaviour can result from hosts altering their habitat preferences. Although infection risk with pathogenic fungus Batrachochytrium dendrobatidis in amphibians is associated with environments favouring its growth, the relationship with microhabitat use has not been examined. Here, we aim to determine if microhabitats used by frogs during their nocturnal activity predict B. dendrobatidis prevalence and infection intensity. Our focal host, Eleutherodactylus coqui, is a habitat generalist that uses multiple habitats from the forest floor to the canopy. We analysed data on B. dendrobatidis occurrence in 157 adults and 122 juveniles at El Yunque National forest in Puerto Rico. We categorized each individual’s nocturnal microhabitat as forest floor, curled palm fronds in the floor, arboreal bromeliads and foliage or tree trunks 50 cm to 2.5 m above ground. We found that frogs on the forest floor had the greatest B. dendrobatidis prevalence (73%), compared with those active in vegetation above ground (55%). Overall, the probability of B. dendrobatidis infection in frogs using microhabitats on the forest floor was twice as great as for those on arboreal substrates. Differences in B. dendrobatidis prevalence and intensity in E. coqui may be explained by specific abiotic conditions of microenvironments (temperature and humidity) affecting both pathogen and host, and by the age-specific ecological requirements of hosts. Adults were found to be most active in microhabitats where individuals had lower infection burdens, suggesting pathogen-modulated habitat choice. This work has important implications for the evolutionary dynamics of enzootic diseases and provides data that may inform potential mitigation strategies against a generalist amphibian pathogen.  相似文献   

2.
ABSTRACT

In the Cerrado, native grasslands have been dramatically lost, leading to an alarming decline in populations of bird species that require these vegetation physiognomies. Species such as the Black-masked Finch Coryphaspiza melanotis (Gray, 1840) are vulnerable to extinction and remain poorly studied. The objective of this study was to examine home ranges of the Black-masked Finch at the Parque Nacional da Chapada dos Veadeiros, central Brazil. Ten males were studied in a patch of shrubby grassland (campo sujo) between February and December 2008. The mean sizes of home ranges were 4.47 ± 1.49 ha (Minimum Convex Polygon) and 3.48 ± 1.44 ha (Kernel 95%), and this varied significantly between seasons. Home ranges were significantly larger in the non-breeding dry season than during other periods, and significantly smaller in the breeding season than during other periods. Core areas (Kernel 50%) had a mean of 0.46 ± 0.26 ha. A large overlap of home ranges was observed. The home ranges of all banded males overlapped those of at least three co-specifics, and most had an area overlap of more than 50%. A nest containing an egg and a nestling was found in November. Small and largely overlapped home ranges can be considered as positive for the conservation of the Black-masked Finch. This is because both small grassland fragments and conservation units can substantially contribute to the conservation of its populations through the Cerrado extension.  相似文献   

3.
The annual range of Balkan chamois (Rupicapra rupicapra balcanica) in Giona mountain was found to be 5502 ha, with a low population density (2 individuals/100 ha). Seasonal range patterns varied significantly, with a minimum extent in summer and a maximum in winter (30% and 79% of the annual range, respectively). Summer stress and the rutting period might be associated with the observed aggregated distributions during the summer and autumn (core areas of 28% and 22% of seasonal ranges, respectively, defined after the Fixed Kernel Density Estimator). Chamois were found to use significantly lower altitude habitats in winter (1212 m) than in summer (2223 m), and significantly steeper slopes in winter (35°); aspect was not found to have a significant effect on habitat use. Population structure consisted of kids (21%), yearlings (8%), females (35%) and males (36%). Conservation management for the species should consider poaching, livestock competition and global warming.  相似文献   

4.
《Journal of Natural History》2012,46(31-32):2115-2124
We studied a leaf-litter frog community from an Atlantic Rainforest area in the state of Espírito Santo, south-eastern Brazil. Frogs were sampled using 4 × 4-m plots. We recorded 348 individuals from 13 species. The estimated overall density of leaf-litter frogs in the study area was 6.6 frogs/100 m2 with an estimated overall frog biomass of 0.04 g/ha. Brachycephalus didactylus was the species with the highest estimated density and highest abundance. Five of the litter frog species recorded are considered endemic to the Atlantic Forest and two species are endemic to the state of Espírito Santo, including Euparkerella robusta, which is considered threatened as the result of habitat loss. The overall abundance of leaf litter was positively related to relative humidity and depth of the leaf litter. The relationship between frog body mass and frog abundance was significant, suggesting that a general biological trend in this relationship occurs in our study area.  相似文献   

5.
《Journal of Natural History》2012,46(19-20):1139-1145
Many epiphytic ferns in tropical forest canopies have domatia that provide habitat for arboreal arthropods such as ants. Two species of fern that were predominantly occupied by Crematogaster difformis ants were collected from the canopy of a forest in Borneo. In the fern domatia, two cockroach species, Pseudoanaplectinia yumotoi and Blatta sp., were found to live with C. difformis. Pseudoanaplectinia yumotoi were found in large numbers and accounted for approximately 20% of the total arthropod population, while Blatta sp. comprised only 1% of the arthropods living in the domatia. Behavioural experiments were conducted to evaluate the response of C. difformis workers to newly introduced cockroaches of each species and to allospecific ant workers. Crematogaster difformis workers were highly aggressive and quickly attacked allospecific workers. Both cockroach species could fend off ant attacks; however, dead Blatta sp. were often attacked by the ants while dead P. yumotoi were infrequently bothered.  相似文献   

6.
Phylogenetic relationships of the Aegean Helix cincta and Helix nucula with congeneric species found in Greece were inferred using mitochondrial DNA sequence data. Twenty-three specimens from mainland Greece, Aegean Islands, Cyprus and North Africa were analysed, revealing that (1) H. nucula is monophyletic, (2) H. cincta from Greece and Cyprus is paraphyletic, and so questions arise regarding the taxonomy of this species, and (3) H. cf. cincta from Tunisia might be considered as a distinct evolutionary lineage. Moreover Helix valentini, an endemic species of Kalymnos Island group, is clustered within the lineage of H. c. anatolica, so supporting the synonymy of the two ‘species’, and the elevation of H. c. anatolica to species level. Hence, our results stress the need for a taxonomic reconsideration of H. cincta in the Aegean Sea, indicating that sequence data can prove useful in overcoming taxonomic issues at both species and subspecies level.  相似文献   

7.
《Journal of Natural History》2012,46(23-24):1501-1510
Arboreal species of the family Succineidae (Gastropoda: Pulmonata) eat fungi, algae and diatoms and use plants as microhabitats. However, the specific plant taxa that arboreal succineids use have not been thoroughly examined. In this study, plant species used as microhabitats by two succineid species, Boninosuccinea ogasawarae (Pilsbry) and Boninosuccinea punctulispira (Pilsbry), were examined on the oceanic Ogasawara (Bonin) Islands in the western Pacific Ocean. Boninosuccinea ogasawarae and B. punctulispira were recorded on 23 (four introduced and 19 native) and 37 (four introduced and 33 native) plant species, respectively. More individuals of B. ogasawarae and B. punctulispira were found on abundant plant species than on rare plant species. No significant difference in snail density was found between the introduced (Bischofia javanica) and native (Ardisia sieboldii) tree species. Therefore B. ogasawarae and B. punctulispira may use introduced plants as well as native plants as microhabitats.  相似文献   

8.
Environmental and isolation variables relating to abundance of breeding amphibians, species richness and community structure at different spatial scales were examined in the Dadia-Lefkimi-Soufli Forest National Park, Evros, Greece. Logistic regression and a generalized linear model were used to relate several habitat characteristics to species occurrence and species richness. The community structure responses to breeding-pond features were examined at four spatial scales using canonical correspondence analysis (CCA). The richest communities live in low-altitude ponds, with stony or clay bottoms, high solar exposure and abundant submerged and floating vegetation. The CCA models were significant (p < 0.005) and revealed the influence of altitude, percentage of field and broadleaf forest coverage, and number of water bodies on amphibian species assemblages at all four spatial scales. There is a specific need for holistic management of amphibians that will consider habitat connectivity, particularly between aquatic and terrestrial habitats, at a larger, more interconnected scale.  相似文献   

9.
《Journal of Natural History》2012,46(39-40):2493-2529
The genus Apochinomma Pavesi, 1881 is revised in the Afrotropical Region. The male and female of the type species, A. formicaeforme Pavesi, 1881, are redescribed. Five new species are described: A. malkini sp. nov. (♂ ♀) from Nigeria, A. parva sp. nov. (♂) from Guineé, and A. tuberculata sp. nov. (♀) from the Ivory Coast in the A. formicaeforme species group, and A. decepta sp. nov. (♂ ♀) from South Africa and Mozambique, and A. elongata sp. nov. (♂) from Botswana, Malawi and Tanzania in the A. decepta species group. Another undescribed species, known only from juveniles, belongs to the latter species group. Members of the A. formicaeforme species group mimic Polyrhachis ants and are thought to be primarily arboreal, whereas the A. decepta species group has ground-dwelling or grass-dwelling representatives that mimic large ground-dwelling ponerine ants. A single case of A. formicaeforme feeding on its model, Polyrhachis gagates, is noted. http://www.zoobank.org/urn:lsid:zoobank.org:pub:04116235-B195-48B0-B27E-076DAF4F51FD  相似文献   

10.
《Journal of Natural History》2012,46(11-12):641-666
Three new troglobitic species of rhagidiid mites of the genus Troglocheles – two from northern Italy, Troglocheles quinquesolenidiata sp. nov. and T. lanai sp. nov., and T. christiani sp. nov. from Austria – are described. A key to adults of the known species of the genus Troglocheles Zacharda of the world is given. In these vicariant species the different apomorphic morphological traits, troglomorphisms, are discussed in aspects of allopatric speciation, climatic relict hypothesis and evolutionary processes of adaptation to specific niches and time of occupation of the subterranean habitat. All new taxa are authored by M. Zacharda only.  相似文献   

11.
《Journal of Natural History》2012,46(29-30):1891-1910
One hundred and ninety-one frogs collected in Papua New Guinea from 10 species of the genus Litoria, namely, L. angiana, L. arfakiana, L. caerulea, L. congenita, L. eurynastes, L. gasconi, L. infrafrenata, L. iris, L. kumae and L. modica, were examined for helminths. Eighteen species of helminths were found: one species of Monogenea, Parapolystoma bulliense; three species of Digenea, Diplodiscus amphichrus, Halipegus zweifeli and Mesocoelium monas; 13 species of Nematoda, gravid specimens of Aplectana macintoshii, Cosmocerca novaeguineae, Falcaustra papuensis, Maxvachonia adamsoni, Maxvachonia flindersi, Maxvachonia ingens, Meteterakis crombiei, Moaciria moraveci, Parathelandros mastigurus, Physalopteroides milnensis, Pseudorictularia dipsarilis, Seuratascaris numidica, and larvae (in cysts) of Abbreviata sp. and, one species of Acanthocephala, Pseudoacanthocephalus bufonis. Mean number of helminth species per host species was 3.0 ± 1.4 SD (range 1–5), mean number of helminth species per infected frog was 1.1 ± 0.4 SD (range 1–2), and mean number of helminths per infected host was 33.3 ± 5.8 SD (range 1–36). Twenty-eight new host records and two new locality records are reported. The biogeography of the recovered helminths is discussed.  相似文献   

12.
Water accumulations in vegetal structures, known as phytotelmata, serve as aquatic habitats for many insects, including mosquitoes. Among them, Culex (Phytotelmatomyia) is composed by a few species that are highly specialized and poorly known. The objective of this study was to evaluate the association between sunlight conditions and the abundance of immature stages of Culex (Phytotelmatomyia) species in the axils of Eryngium pandanifolium. A forest patch with a dense population of E. pandanifolium in the Lower Delta of the Paraná River (Entre Ríos province, Argentina) was sampled twice a month between December and May. A total of 880 plants were inspected in 220 sample zones defined by a combination of location within the patch and sunlight condition. All individuals collected (n = 521) belonged to Culex (Phytotelmatomyia) hepperi (56%), Culex (Phytotelmatomyia) castroi (40%), and Culex (Phytotelmatomyia) renatoi (4%). According to generalized linear models, the habitat availability (i.e. water presence) was positively associated with sun exposure, but not with the location within the patch. Mosquito presence and abundance were positively related only to water volume. Coexistence of C. hepperi and C. castroi was more frequent than would be expected by chance. Further studies to understand the effects of sunlight and plant architecture on water dynamics are needed.  相似文献   

13.
《Journal of Natural History》2012,46(35-36):2215-2230
Four new species of Smicridea (Rhyacophylax) are described from Argentina and Bolivia. Smicridea (Rhyacophylax) bifida sp. nov., S. (R.) elisae sp. nov. and S. (R.) valeni sp. nov. are described from the male; S. (R.) thermophyla sp. nov. is described as the first species of Smicridea from thermal springs. The larva and pupa of S. (R.) thermophila were associated using the metamorphotype method. New distributional records of S. (R.dithyra, S. (R.atrobasis, S. (R.peruana and S. (R.pampeana are included. Morphological characters of male S. (R.) peruana that were not mentioned before are included. Illustrations of all taxa named in this paper are included.  相似文献   

14.
Home range size and foraging habitat use in breeding lesser kestrels (Falco naumanni), a bird species of conservation concern, were investigated during the breeding season of the species in 2008 in an intensively cultivated area of central Greece, using radio-tracking. Grasshopper (the main prey) densities were measured at the most important habitats (cotton, cereals, grasslands and margins). Home ranges were not significantly different between sexes either as overall means or during incubation and nestling periods. Movements of both sexes were non-random during incubation but random during the nestling period. Habitats used by males during incubation ranked as: margins > other > cotton > corn > cereals and during nestling period as: cereals > margins > grasslands > corn > cotton. Female habitat use greatly differed ranking as cereals > cotton > grasslands during incubation and as grassland > cotton > corn > cereals > margins during nestling period. Female habitat use seemed to be in disagreement with the conditions generally favouring prey availability, probably for reasons associated with low and uniform distribution of grasshopper densities over the habitats.  相似文献   

15.
《Journal of Natural History》2012,46(9-10):565-598
Thirteen new species of the genus Helina are described: H. briaroacantha sp. nov., H. corrugicerca sp. nov., H. cuneicauda sp. nov., H. curvoifemoralisa sp. nov., H. deqinensis sp. nov., H. dianibrunneigena sp. nov., H. kytososurstylia sp. nov., H. mesolobata sp. nov., H. nigrointermedia sp. nov., H. nudusimacula sp. nov., H. spinusiabdomena sp. nov., H. tigrisipedisa sp. nov., and H. yanzigouensis sp. nov.  相似文献   

16.
Egg deposition by the soil mites Lasioseius ometes (Oudemans, 1903) and Hypoaspis kargi Costa, 1968 was observed using continuous video-monitoring. The process in both species was found to consist of four distinct phases. In Phase 1, both species engage in pre-ovipositional activity prior to the egg being extruded from the genital opening. In L. ometes, the female often selects a substrate depression for egg laying and examines the depression carefully with the gnathosoma and legs I before oviposition. In H. kargi, egg deposition sites are chosen without regard for substrate depressions. Phase 1 lasted approximately 3 minutes for both species. Phase 2 involved egg extrusion and holding of the egg beneath the gnathosoma. Phase 2 lasted approximately 20 times longer in L. ometes (5 minutes) than in H. kargi. Alteration of the egg surface in the form of thorn-like outgrowths was recorded in L. ometes. Egg deposition occurs in Phase 3, and in L. ometes the egg is generally placed at the deposition site using the chelicerae. Hypoaspis kargi also uses the chelicerae for egg manipulation, but also adjusts orientation of the egg with legs I. The sticky nature of egg surface in H. kargi may provide a means for the female to effectively cover the exposed egg with a protective layer of soil particles. Egg deposition in both species occurred in less than 90 seconds. Phase 4 involves egg covering, but behaviour of the female during this last phase differs markedly between the two species. In L. ometes, the female tends to remain close to the egg, whereas in H. kargi the female moves away from the egg to search for substrate particles appropriate for its covering. The average time for Phase 4 in H. kargi was approximately four times longer (80+ minutes) than in L. ometes.  相似文献   

17.
There is a general lack of information concerning the diversity of bees belonging to the Euglossini tribe in Cerrado areas closest to the Brazilian Amazon. The state of Maranhão is situated in the northeast Brazilian Cerrado and has become the agricultural frontier of the country due to the advancement of monoculture and cattle farming. These activities have suppressed animal and plant populations in large areas of the Cerrado remnants, for which we have not yet obtained adequate scientific knowledge of local species. The objective of this study was to conduct a survey of Euglossini fauna in the northeast Cerrado. We evaluated the variation in species richness, composition and abundance between two distinct vegetation types: Cerrado sensu stricto (s.s.) and gallery forest. Male bees were captured from 7:00 a.m. to 5:00 p.m. over two consecutive days. Captures were carried out once per month from July 2012 to December 2013, using a combination of passive and active collection techniques, including baited traps, as well as a collector with an entomological net to collect bees near traps. We collected a total of 766 Euglossini males belonging to 24 species and five genera. The most abundant species were Eulaema bombiformis, Eulaema nigrita and Eulaema cingulata for the gallery forest site, whereas Eulaema nigrita, Euglossa melanotricha and Euglossa cordata were more abundant in the Cerrado s.s. The gallery forest yielded a higher number of male Euglossini (n = 503, 21 species) compared with the Cerrado s.s. (n = 263, 16 species). The presence of seven exclusive species in the gallery forest and three in the Cerrado s.s. indicated that both environments are important for the maintenance of Euglossini species in this region and highlight the increasing need for conservation programmes for the protection of Cerrado environments.  相似文献   

18.
ABSTRACT

We evaluated the activity period, thermal ecology, habitats, and preference for microhabitats of the skink Mabuya arajara in a humid forest environment on the slope of the Araripe Plateau, Brazil. A total of 283 lizards were observed. The lizards were found to be diurnally active (unimodal type pattern), with peak activity during the hottest hours of the day (1100 to 1200). About habitat use, the majority of individuals (73.8% N = 209) were recorded in the narrow transitional area, in the edges of the forest; while 26.4% of individuals were observed in open areas and no observations were made in dense forest. Seven different types of microhabitats were used, with fallen palm leaves (Arecaceae) being the preferred (47.7% N = 135). Considering all lizards, microhabitat niche breadth was 3.27. Males and females presented a high overlap (0.95) in microhabitat use. The average Tc recorded for M. arajara was 32.06 ± 2.72°C. Body size (SVL) did not influence body temperature (F = 0.51, P = > 0.05). Most of the animals were observed with their bodies completely exposed (67.84%, N = 192), 18.37% (N = 52) were semi-exposed and 13.79% (N = 39) were in shelters. Among animals with some degree of sunlight exposure, 57.59% (N = 163) were in shadows, 25.10% (N = 71) were under sunlight filtered by vegetation, and 17.31% (N = 49) were under direct sunlight.A review of the ecology of Mabuya spp. shows that several features appear to be conserved among members of the genus.  相似文献   

19.
The use of space by animals is determined by environmental conditions, biological and ecological adaptations and interactions and mostly by resource availability. We sampled two species of Neotropical mammals to investigate their use of different strata in Atlantic Forest habitat in Brazil, as well as the home range sizes and movements of both sexes of each species. We found no difference in home ranges and movements between the sexes and species, but we found differences in the use of strata, with Gracilinanus microtarsus mostly using the canopy and Marmosops incanus using the ground. Gracilinanus microtarsus males mostly use the understorey in the wet season and the canopy in the dry season. We believe that these patterns of strata use reflect intrinsic characteristics of the species; and the shifts in resources and interspecific competition, which are lower in the dry season, seem to be responsible for the shifts in space use observed for G. microtarsus males. We recommend studies with spool-and-line techniques or radio tracking to further test refined hypotheses regarding the use of space, including the role of territoriality in females.  相似文献   

20.
《Journal of Natural History》2012,46(23-24):1441-1465
In Argentina, five genera and 34 species are recorded, in the subfamilies Rhopalinae and Serinethinae. Harmostes apicatus Stål; H. brevispinus Blöte; H. corazonus Distant; H. corizoides Jensen-Haarup; H. dorsalis Burmeister; H. gravidator (Fabricius); H. imitabilis Harris; H. insitivus Harris; H. marmoratus (Blanchard); H. minor (Spinola); H. parafraterculus Göllner-Scheiding; H. petulans Harris; H. procerus Berg; H. prolixus Stål; H. reflexus viscens (Dallas); H. serratus (Fabricius); H. signoreti Reed; Jadera aeola aeola (Dallas); J. choprai Göllner-Scheiding; J. decipiens Göllner-Scheiding; J. golbachi Göllner-Scheiding; J. haematoloma (Herrich-Schaefer); J. obscura (Westwood); J. parapectoralis Göllner-Scheiding; J. sanguinolenta (Fabricius); Niesthrea agnes Chopra; N. josei Göllner-Scheiding; N. pictipes (Stål); N. similis Chopra; N. vincentii (Westwood); Liorhyssus hyalinus (Fabricius); L. lineatoventris (Spinola); Xenogenus gracilis Berg; X. picturatum Berg; and X. extensum Distant. New locality records are given for Buenos Aires; Catamarca; Corrientes; Córdoba; Chaco; Entre Ríos; Jujuy; La Pampa; Mendoza; Misiones; Neuquén; Río Negro; Salta; San Juan; San Luis; Santiago del Estero; Tierra del Fuego.  相似文献   

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