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1.
Among the 13 Mico species recognized by the IUCN Red List of Threatened Species, six are listed as “Data Deficient”. The geographic range of most of the Mico species has been estimated from only a few records. We report new localities and the geographic extension of Mico chrysoleucos. In addition, we confirmed the presence of the species in two distinct protected areas. We modeled the habitat suitability of M. chrysoleucos using the maximum entropy method and including new records obtained by the authors in the state of Amazonas, Brazil. From the total area of occurrence calculated for the species, 22.8% is covered by protected areas and indigenous lands. The annual mean deforestation rate estimated between 2000 and 2015 was 2.95%, and the total area deforested by 2015 was 3354 km2 or 8.6% of the total distribution limits of the species. The habitat lost between 2000 and 2015 was 3.2% (1131 km2) of the total potential distribution, while the habitat loss area legally protected was 31 km2, and the habitat loss in settlements was equal to 691 km2. Our results extend the geographic distribution of the species about 100 km farther south, with the Maracanã River being a possible geographic barrier for the species. The significantly low rate of habitat loss inside protected areas and indigenous land, when compared to unprotected areas, points out the importance of these areas to M. chrysoleucos conservation. The species is relatively wide-ranging, legally protected, and resilient to regional anthropic threats. However, the hydroelectric schemes and the improvement of the road system in southern Amazonia pose an imminent threat to the species.  相似文献   

2.
Loons (family Gaviidae) breed in small ponds and lakes across Arctic landscapes and are high level predators in the lake ecosystems. As such, they may serve as sentinel species, warning humans of alterations in habitat and ecosystem integrity in a region that is undergoing vast change due to climate warming. Here, we characterized the abundance and habitat use of four arctic breeding species of loons in the plains and surrounding mountains of western Chukotka, Russia. Loon surveys were conducted on foot and by boat from 2009–2015. Loon species differed in their use of the four lacustrine habitat types within the study area. In yedoma habitat, the yellow-billed loon (Gavia. adamsii) was the most abundant (0.593 birds/km2); on fluvial plain habitat, Pacific loons (G. pacifica) outnumbered other loons (0.701 birds/km2); mountain valleys were inhabited similarly by pacifica (0.354 birds/km2) and red-throated loons (G.stellata; 0.307); and maritime tundra was used only by pacifica (1.13) and Arctic loons (G. arctica; 0.553). G. adamsii was not observed in mountain valleys or maritime tundra. Mountainous portions of rivers were predominantly occupied by stellata and pacifica, and lowland rivers by stellata, pacifica and arctica. There was a significant difference in the size of lakes occupied by the four congeners. The largest loon, adamsii, occupied the largest lakes (0.69 km2), 80% larger than lakes utilized by pacifica (0.39 km2) and arctica (0.38 km2), and 35 times larger than stellata (0.02 km2). Most lakes were occupied by a single loon species (125/162, 77.2%).  相似文献   

3.
The western Bering Sea is an important region that is used by many nekton species for feeding. From the seasonal aspect, these waters are characterized by pronounced dynamics of the abundance and structure of the nekton community. The pattern of seasonal variations in the total biomass, composition, and structure of nekton in the upper epipelagic layer (0–50 m) of this region are considered based on the data of the complex studies conducted by the Pacific Research Fisheries Center (TINRO Center) in the deep-sea basins of the western Bering Sea and the Navarin area in June–October, 2003–2015. During June–October, the total nekton biomass changed by more than an order of magnitude: from 100 kg/km2 in early June it increased to a maximum of 2700 kg/km2 in the middle of August and then declined significantly, to 200 kg/km2, in late October. The major contribution to the nekton biomass was made by Pacific salmon (Oncorhynchus spp.), mainly O. keta, as well as by the boreopacific gonate squid (Boreoteuthis borealis) and the shortarm gonate squid (Gonatus kamtschaticus). As well, walleye pollock (Theragra chalcogramma), Pacific herring (Clupea pallasii), and capelin (Mallotus villosus) were abundant in waters near the shelf. The dynamics of the species structure can be divided into three periods: (1) early summer, from June to the second 10 days of July, when pre-anadromous pink (O. gorbuscha) and chum salmon predominate and the species diversity is at a medium level (the polydominance index is 3.5–4.0); (2) summer, from the third 10 days of July to the second 10 days of September, when chum salmon becomes dominant (more than 70% of the biomass) and the species diversity is at a minimum (1.5–2.0); and (3) autumn, from the third 10 days of September to October, when common species such as chum salmon, sockeye salmon, and boreopacific gonate squid have relatively equal proportions, the proportion of pink salmon underyearlings is also high, and the species diversity is at a maximum (4.5). The pattern of the spatial distribution in the early summer period is characterized by active formation of the nekton community due to the large-scale migrations from the central and eastern Bering Sea and from the Pacific Ocean. In the summer period, the concentration of the nekton in the western Bering Sea, particularly in the Aleutian Basin, reaches the maximum level and the migratory activity decreases. Reverse migration processes are observed in the autumn period: a major portion of the nekton biomass redistributes to the southeastern Commander Basin for further movement to the ocean and the central Bering Sea.  相似文献   

4.
The Cerrado Biome is the second largest in Brazil covering roughly 2 million km2, with varying features throughout its area. The Biome is endangered but it is also source of animal species for rural, green urban and degraded rainforest areas. Ticks are among Cerrado species that establish at anthropogenic sites and although information about them is steadily increasing, several features are unknown. We herein report tick species, abundance and some ecological relationships within natural areas of the Cerrado at higher altitudes (800–1500 m) within and around Serra da Canastra National Park, in Minas Gerais State Brazil. In total of 1196 ticks were collected in the environment along 10 campaigns held in 3 years (2007–2009). Amblyomma sculptum was the most numerous species followed by Amblyomma dubitatum and Amblyomma brasiliense. Distribution of these species was very uneven and an established population of A. brasiliense in the Cerrado is reported for the first time. Other tick species (Amblyomma ovale, Amblyomma nodosum, Amblyomma parvum, Ixodes schulzei and Haemaphysalis leporispalustris) were found in lesser numbers. Domestic animals displayed tick infestations of both rural and urban origin as well as from natural areas (Rhipicephalus sanguineus sensu lato, Rhipicephalus microplus, Dermacentor nitens, A. sculptum, A. ovale, Amblyomma tigrinum, Argas miniatus). Amblyomma sculptum had the widest domestic host spectrum among all tick species. DNA of only one Rickettsia species, R. bellii, was found in an A. dubitatum tick. Several biological and ecological features of ticks of the studied areas are discussed.  相似文献   

5.
The San Martin titi monkey (Plecturocebus oenanthe) is endemic to a small area of northern Peru and is considered Critically Endangered on the IUCN due to massive habitat loss. Between 1994 and 2005 small scale reforestation efforts in the 23.5 ha area of Pucunucho have led to the recuperation of habitat from an area of pasture and crop lands. The first record of P. oenanthe re-establishment in the area is from 2010, although re-establishment probably began earlier. We carried out short population surveys using triangulation to monitor densities of P. oenanthe in Pucunucho in 2011, 2012 and 2016. We estimate the current population of P. oenanthe in this area at 27 individuals, giving population densities of 35 groups/km2 and 124 individuals/km2. The successful regeneration of habitat and natural re-population of the area by this Critically Endangered species provides evidence of successful reforestation based conservation activities for this and potentially other primate species. Although now protected as a Private Conservation Area, Pucunucho remains threatened.  相似文献   

6.
A study of epibiosis of the brown alga Costaria costata in the sublittoral zone of Vostok Bay, Sea of Japan during the spring and summer of 2016 showed that hermit crabs of the following four species accounted for approximately 85% of the total biomass: Pagurus proximus, P. minutus, P. brachiomastus, and P. middendorffii. Of these, the most abundant one (96.5% of the total number of hermit crabs) was P. proximus, the mean aggregation density of which on C. costata (429 ± 221 ind./m2) was higher by an order of magnitude than that in the adjacent area of the bouldery bottom. The size ranges of males and females of this species in aggregations on boulders and those on C. costata were similar, with a predominance of larger individuals on algae. In the size–frequency distribution, three groups of individuals corresponding to three size–age cohorts were differentiated. The male-to-female ratio was 1 : 1.7. Hermit crab aggregations on C. costata are ephemeral; their existence is determined by the duration of the period of algae development, that is, from late spring to the middle of the summer.  相似文献   

7.
The species composition, abundance, and vertical distribution of hermit crabs (Decapoda: Paguroidea) were investigated in Vostok Bay, Sea of Japan, from September 2014 to September 2015. A total of seven species from two families were found in the monitoring area of approximately 5000 m2 located on the bottom within a depth range of 0–11 m: Pagurus minutus, P. proximus, P. brachiomastus, P. pectinatus, P. ochotensis, P. middendorffii (Paguridae), and Areopaguristes hirsutimanus (Diogenidae). Their population density varied from 22 ± 13 to 26 ± 2 ind./m2; the biomass varied from 55.76 ± 26.10 to 93.38 ± 27.00 g/m2. The species composition remained invariable throughout the study period. The proportions of species abundance changed between seasons, as this parameter is largely determined by seasonal migrations of hermit crabs. Pagurus minutus predominated in number in winter and spring (up to 71%); P. proximus, in summer and autumn (up to 47%). In autumn and spring, P. ochotensis and P. pectinatus constituted a major part of biomass (18–25% and 19–20%, respectively). The proportion of a previously abundant species, P. middendorffii, was very small (no larger than 1.3%) during the study period. Another four species of hermit crabs occurred in other parts of Vostok Bay; thus, the fauna of the bay currently includes 11 species of this group.  相似文献   

8.
Lake Tanganyika, the second-oldest and second-deepest lake in the world, harbors an impressive cichlid fish fauna counting about 250 endemic species that are characterized by a great level of ecological, morphological, and behavioral specialization. This study describes and compares cichlid fish communities at two rocky shores with differential human impact in the south of Lake Tanganyika. Species inventories and depth-dependent abundances were elaborated. About 41 and 46 sympatric cichlid species were recorded in the two study sites, respectively. Variabilichromis moorii was the most abundant species (29–60% of total number of fishes), followed by Aulonocranus dewindti (3–19%), Tropheus moorii (12%), Ophthalmotilapia ventralis (4–10%), Eretmodus cyanostictus (6–11%), and Cyathopharynx furcifer (0.01–9%). All other species had abundances below 5%. It further emerged that large cichlids such as Petrochromis species, Cyathopharynx furcifer, and Lobochilotes labiatus were very rare at one location, with frequencies of 0.55% or less. Territorial sizes of three particularly abundant species, Variabilichromis moorii, Aulonocranus dewindti, and Tropheus moorii, were assessed by behavioral observations. We distinguished between territorial core areas and total defended area, yielding average core areas between 0.4 (V. moorii) and 1.6 m2 (T. moorii), and total defended areas averaging for each species between 1.6 (V. moorii) and 5.0 m2 (A. dewindti) with no significant differences between the two study sites. The data on individual densities are also relevant for evolutionary studies, in that they allow more accurate calculations of effective population sizes.  相似文献   

9.
Spadicoides lushanensis sp. nov., S. multiseptata sp. nov. and S. rostrata sp. nov. are described and illustrated from specimens collected on dead branches of unidentified plants in Lushan Mountain, China. Spadicoides lushanensis is characterized by obclavate, rostrate, pale brown, 40–65?×?4.5–5.5 μm, smooth, 6–8-euseptate conidia. Spadicoides multiseptata is easily distinguished by obclavate, smooth, 11–15-euseptate, 65–115?×?11.5–13 μm, brown to pale brown conidia with a subacute apex. Spadicoides rostrata differs from other described Spadicoides species by obclavate, rostrate, pale brown, 40–65?×?10.5–12.5 μm, smooth, predominantly 5-euseptate conidia. A dichotomous key to Spadicoides species is provided.  相似文献   

10.
The muscles of the male genitalia were studied for the first time in two species endemic to the Oriental zoogeographical region, namely Curetis bulis from the subfamily Curetinae (Lycaenidae) and Paralaxita damajanti from the tribe Abisarini (Riodinidae). Both taxa possess a common plan of musculature reflected in the positions of muscles m1, m2(10), m5(7), m7(6), m21, and m28. Two new autapomorphies of Curetis bulis were discovered: the splitting of m4 into two muscles and a shift of the attachment site of one of these muscles onto the dorsal area of the anellus. Apomorphic differences in the position of the genital muscles were found between Paralaxita damajanti and the previously studied Polycaena tamerlana from the family Riodinidae. A new synapomorphy between the latter two species, namely splitting of the aedeagus protractors m6(5), was also found.  相似文献   

11.
12.
Populational parameters of primates in the remaining southeastern Brazilian Atlantic Forest have been estimated, but investigations are biased to coastal evergreen sites. In this study density of three primate species was assessed through line-transect surveys in four semi-deciduous forest fragments (240 to 1450 ha) in Fazenda Barreiro Rico, eastern range of central Plateau of São Paulo state, Brazil. A total of 274 km was surveyed from January to October 2000. I estimated densities via DISTANCE software. Two of the largest fragments contained five primate species while two of the smallest ones harboured, respectively, four and two species. Densities of Cebus apella (15.34–47.92 ind./km2), Alouatta guariba (8.32–34.61), and Brachyteles arachnoides (19.92–35.11) were considerable. Differently from C. apella and A. guariba, B. arachnoides presented a density higher than previously estimated for the largest patch. The hypothetical minimum total population of B. arachnoides (601) may be the largest in semi-deciduous sites. This reinforces the value of the area in terms of its relative contribution for conservation of this endangered species. The narrow spatial scale distribution of forest fragments at Barreiro Rico and its proximity to academic institutions make the site suitable for programs of forest connectivity, studies on conservation biology, and wildlife management endeavours.  相似文献   

13.
A new species of Magnolia is described for the flora of Brazil, based on material from Bahia and Minas Gerais states. This species represents the first record of Magnoliaceae in the Northeastern region of Brazil. Magnolia brasiliensis differs from all other Brazilian species of Magnolia by having adaxially glossy leaves and differs from M. ovata by having a lower number of stamens and carpels. Despite its large extent of occurrence, the conservation status attributed to the new species is Endangered, mainly based on the low number of mature individuals in each subpopulation (< 50) and an area of occupancy of less than 16 km2.  相似文献   

14.
Antarctica is a remote and isolated biotope which makes it an ideal location for studying new and endemic species. Since there is little literature available on the diversity of ciliates in this area, a taxonomic survey of ciliates from melt-water of Collins glacier, King George Island, was carried out from January to March 2006. As a result, the morphology and infraciliature of five ciliates, including one new species, are described using live observations and silver staining: Gastronauta multistriata nov. spec., Neokeronopsis asiatica Foissner et al., 2010, Paraholosticha muscicola Kahl, 1932, Oxytricha sp., and Cyclidium glaucoma Müller, 1786. Gastronauta multistriata nov. spec. is distinguished from its congeners by the following combination of characters: cell size in vivo on average 80 × 40 μm; 5–9 kineties in left ciliary field; 18–23 kineties in right ciliary field, including 10–12 postoral kineties; 7–10 preoral kineties; dorsal brush along anterior dorsal margin, consisting of 5–8 groups of basal bodies. The only minor differences between the current population of N. asiatica and a previously described Antarctic population are the numbers of caudal cirri (6–10 vs. 8–15) and dorsal kineties (11–13 vs. 12–18). Paraholosticha sterkii is synonymised with P. muscicola. The Antarctic population of C. glaucoma corresponds well with a former population from China, the only difference being the number of kinetids in SK n (11–17 vs. 9–11). This work will contribute to the understanding of ciliate diversity in this little studied area.  相似文献   

15.
16.
Taxonomic and phylogenetic studies of Haploporus were carried out. Three species in Haploporus, H. cylindrosporus, H. septatus and H. subpapyraceus, are described as new based on morphological differences and molecular phylogenetic analyses inferred from the internal transcribed spacer (ITS), the large subunit nuclear ribosomal RNA gene (nLSU), the small subunit mitochondrial rRNA gene (mtSSU), the second subunit of RNA polymerase II (rpb2) and the translation elongation factor 1-α gene (TEF1) sequences. Haploporus cylindrosporus is characterized by big irregular crystals occasionally present in the subiculum, an abundant oily substance among hyphae and typically cylindrical basidiospores 10–11.5?×?4.5–5 μm; H. septatus differs from other species in the genus by its leathery to corky basidiomata when dry, small round pores (5–6 per mm), simple septate skeletal hyphae at the edge of the dissepiments, and oblong to ellipsoid basidiospores 8.5–11?×?5–6 μm; H. subpapyraceus is separated by white to cream basidiomata, numerous apically simple septate cystidioles and ellipsoid basidiospores 9–12?×?5.5–8 μm. An identification key to accepted species of Haploporus is provided.  相似文献   

17.
18.
This paper examines the influence of the location of settlements, railroads, and highways on the spatial structure of the Otis tarda population in the Trans-Volga region that was studied in the years 1998–2016 in a model area of 12000 km2 that is located in the southern part of the Saratov Trans-Volga region. The zone of the impact made by our estimated disturbance factor due to the movement of people and a variety of ground vehicles along various-purpose roads on the territorial distribution of bustards in autumn can be denoted as a 300–500 m width band on both sides of the transport communications. Shelterbelts that were created along transport communications render a beneficial effect on the distribution of O. tarda and reduce the influence of the disturbance factor. Furthermore, crop rotation fields with side sizes of more than 1 km can be considered a factor that compensates for the anxiety of birds. We have found that in the Saratov Trans-Volga region, because of the large size of crop rotation fields and significant development of roadside and shelter belts, no special measures are required to protect O. tarda such as restrictions on the movement of people and vehicles over the territory where this species lives.  相似文献   

19.
Morphological and molecular characterisation of echinostome specimens (Digenea: Echinostomatidae) recovered in one Anas platyrhynchos L. and one Cygnus atratus (Latham) (Anseriformes: Anatidae) from New Zealand revealed the presence of two known species, Echinostoma miyagawai Ishii, 1932 and Echinoparyphium ellisi (Johnston & Simpson, 1944) and two species new to science. Comparative morphological and phylogenetic analyses supported the distinct species status of Echinostoma novaezealandense n. sp. ex Branta canadensis (L.), A. platyrhynchos and C. atratus, and Echinoparyphium poulini n. sp. ex C. atratus. Echinostoma novaezealandense n. sp., a species of the “revolutum” species complex characterised by the possession of a head collar armed with 37 spines, keyed down to E. revolutum but was distinguished from the latter in having a much narrower body with almost parallel margins, longer oesophagus, wider cirrus-sac, larger seminal vesicle, much smaller ventral sucker, ovary, Mehlis’ gland and testes, more anteriorly located ovary and testes, and distinctly smaller eggs (81–87 × 42–53 vs 106–136 × 55–70 µm). This new species appears similar to Echinostoma acuticauda Nicoll, 1914 described in Australia but differs in having a longer forebody, more posteriorly located ovary and testes, and much smaller eggs (81–87 × 42–53 vs 112–126 × 63–75 µm). Echinoparyphium poulini n. sp. is differentiated from the four species of Echinoparyphium possessing 37 collar spines considered valid as follows: from E. chinensis Ku, Li & Chu, 1964 in having a much smaller body, four (vs five) angle spines and simple seminal vesicle (vs bipartite); from E. schulzi Matevosyan, 1951 in having a less robust body at a comparable body length, much smaller ventral sucker, ovary and testes, and longer but narrower eggs (87–109 × 50–59 vs 70–85 × 60–84 µm); and from the two smaller forms, E. serratum Howell, 1968 and E. aconiatum Dietz, 1909, in a number of additional metrical features correlated with body size and especially in the possession of much larger collar spines. Partial fragments of the mitochondrial nad1 and 28S rRNA genes were amplified for representative isolates of the four species and analysed together with sequences for Echinostoma spp. and Echinoparyphium spp. available on GenBank. Phylogenetic analyses based on the mitochondrial nad1 gene revealed congruence between the molecular data and species identification/delineation based on morphology; this was corroborated by the 28S rDNA sequence data.  相似文献   

20.
New and rare liparid fishes (Liparidae, Scorpaeniformes) are found and described. Careproctus armatus Andriashev, 1991 sampled off the South Sandwich Islands (at a depth 2281–2369 m); it is the second record of the species. Four species are collected in the vicinity of the South Shetland Islands: Careproctus parini Andriashev et Prirodina, 1990 (off King George Island, 573–861 m), Paraliparis meganchus Andriashev, 1982 (off Elephant Island, 559 m), P. monoporus Andriashev et Neyelov, 1979 (off Elephant Island, 559 m) and Paraliparis specimens, most similar to P. tompkinsae Andriashev, 1992 (off King George Island, 766–861 m). Paraliparis charcoti Duhamel, 1992 recorded at the eastern part of the Weddell Sea (475–633 m). Paraliparis, most similar to P. tetrapteryx Andriashev et Neelov, 1979, found in the Southwestern Atlantic (1200 m). Four new species are described. Paraliparis porcus sp. nov. based on one male SL 85 mm from off the South Shetland Islands (Elephant Island, 332–374 m). Paraliparis acutidens sp. nov. described from the juvenile SL 115 mm, sampled in the western part of the Scotia Sea (3721–3723 m). Paraliparis kocki sp. nov. known from 3 adults caught in the depression of the Bransfield Strait (1914–1920 m), isolated from the Weddell Sea by shallower waters. The only specimen of the Paraliparis mexicanus sp. nov. collected in the tropical Pacific off Mexico at depth not more than 900 m.  相似文献   

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