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1.
Summary  A new monotypic genus and a new species of Monimiaceae, Grazielanthus arkeocarpus from the Brazilian Atlantic coastal forest are described, illustrated and compared with morphologically related taxa. The new taxon occurs in the State of Rio de Janeiro in the central coastal plain and was collected in the Po?o das Antas Biological Reserve, municipality of Silva Jardim (22°30′– 22°33′S; 42°14′– 42°19′W). The new taxon is represented by dioecious climbing shrubs of the sub-canopy that have urceolate, four-lobed flowers and a fleshy hypanthium that is closed until the fruit ripens. When ripe, the hypanthium ruptures irregularly and the fruitlets are exposed. The relationships between the new genus and other neotropical (Hennecartia J. Poiss. and Macrotorus Perkins) and paleotropical (Palmeria F. Muell.) genera are discussed.  相似文献   

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3.
In this study the first length–weight relationships are provided for Helcogrammoides cunninghami and Ribeiroclinus eigenmanni inhabiting subtidal rocky areas in northern Patagonia, and for Hypleurochilus fissicornis inhabiting intertidal rocky areas in Buenos Aires Province. Specimens were collected between 2009 and 2016, from seven different locations in northern Patagonia and Buenos Aires Province (Southwest Atlantic Coast; 37°–42°S), using a trawling dredge or a small hand net. New maximum lengths were recorded for R. eigenmanni and H. fissicornis.  相似文献   

4.
Argas neghmei Kohls & Hoogstraal is a Neotropical tick species parasite of poultry and man in the arid western of the southern cone of America in Argentina and Chile. Males, females and nymphs of an argasid were collected from 20 to 22 of June, 2007 in nests of Creamy-breasted Canastero, Asthenes dorbignyi (Reinchenbach) (Passeriformes: Furnariidae) at about 7 km S of La Poma (24°46′S, 66°12′W) and a male tick at 24°48′S, 66°10′W on Nov 27, 2008, Salta province, Argentina. Scanning electron microscope micrographies and sequences of 16S rDNA confirmed that the ticks found were A. neghmei. Development in breeding areas of A. dorbignyi is probably a source of infestation for animal premises and houses. However, the role of other unknown wild birds may also contribute to the invasion of A. neghmei in chicken houses or residences.  相似文献   

5.
The Antarctic fur seal Arctocephalus gazella at Gough Island (40°20′S, 09°54′W) in the South Atlantic Ocean, first seen in October/November 2005, was recorded again in September–October 2009. Up to three different individual Antarctic fur seals were sighted on a single day, on a particular beach. A total of seven different individuals were recorded over a 3-week period, well before the onset of the breeding (pupping) season of the resident population of Subantarctic fur seals A. tropicalis. Positively identified individuals were all male, mostly subadult and lean. Only a fraction (~20%) of the available beaches was searched, and it is unknown if the Antarctic fur seals were still present at Gough Island during the austral summer breeding season of southern fur seals.  相似文献   

6.
Summary  Recently collected material of Sesbania (Leguminosae subfam. Papilionoideae) from western Ethiopia shows variation and character combinations not recorded in J. B. Gillett’s revision of Sesbania from Africa and tropical Arabia from 1963 and combines three taxa in his revision, S. sudanica J. B. Gillett, S. sudanica subsp. occidentalis J. B. Gillett and S. hepperi J. B. Gillett. The three taxa are therefore united into one more variable species, S. sudanica, that can still be distinguished from other Sesbania species with no or hardly any free tips on the appendages on the standard by having the style pilose or tomentose and a long sterile rostrum on a non- or only faintly torulose pod. The amended S. sudanica is distributed throughout the Sudanian woodland zone from near the Atlantic to the foothills of the Ethiopian highlands. The distribution area agrees well with the Sudanian region in Frank White’s classification of African phytochoria.  相似文献   

7.
Invasive epiphyte Lophocladia lallemandii macroalga induces changes in the erect bryozoan Reteporella grimaldii at shallow Posidonia oceanica meadows at a Mediterranean pristine location. Bryozoan densities at noninvaded seagrass plots (88.32 ± 3.11 colonies m−2) are higher than those at invaded plots (13.39 ± 1.09 colonies m−2) with a fourfold decrease in number of colonies. Activation of enzymatic pathways (catalase, superoxide dismutase, glutathione peroxidase) and increase in lipid peroxidation malondialdehyde (MDA) [0.80 ± 0.06 nmol/mg prot at Posidonia oceanica plots to 1.08 ± 0.04 nmol/mg prot at L. lallemandii (P < 0.05)] is observed on sessile bryozoans as response to anoxia caused by L. lallemandii. δ13C of bryozoan isotopic composition differed among treatments, covering a broad range (−19.30‰ invaded to −2.84‰ at noninvaded plots), suggesting modification of food sources. Induced shifts of a filter-feeding erect bryozoan by dense algal turfs at invaded seagrasses are demonstrated, highlighting the need to further address interaction across natural communities and alien species invaded systems before further cascade effects are driven.  相似文献   

8.
A growing body of knowledge on the diversity and evolution of intertidal isopods across different regions worldwide has enhanced our understanding on biological diversification at the poorly studied, yet vast, sea–land interface. High genetic divergences among numerous allopatric lineages have been identified within presumed single broadly distributed species. Excirolana mayana is an intertidal isopod that is commonly found in sandy beaches throughout the Gulf of California. Its distribution in the Pacific extends from this basin to Colombia and in the Atlantic from Florida to Venezuela. Despite its broad distribution and ecological importance, its evolutionary history has been largely neglected. Herein, we examined phylogeographic patterns of E. mayana in the Gulf of California and the Caribbean, based on maximum‐likelihood and Bayesian phylogenetic analyses of DNA sequences from four mitochondrial genes (16S rDNA, 12S rDNA, cytochrome oxidase I gene, and cytochrome b gene). We compared the phylogeographic patterns of E. mayana with those of the coastal isopods Ligia and Excirolana braziliensis (Gulf of California and Caribbean) and Tylos (Gulf of California). We found highly divergent lineages in both, the Gulf of California and Caribbean, suggesting the presence of multiple species. We identified two instances of Atlantic–Pacific divergences. Some geographical structuring among the major clades found in the Caribbean is observed. Haplotypes from the Gulf of California form a monophyletic group sister to a lineage found in Venezuela. Phylogeographic patterns of E. mayana in the Gulf of California differ from those observed in Ligia and Tylos in this region. Nonetheless, several clades of E. mayana have similar distributions to clades of these two other isopod taxa. The high levels of cryptic diversity detected in E. mayana also pose challenges for the conservation of this isopod and its fragile environment, the sandy shores.  相似文献   

9.
The study of the subfamily Cytheropterinae from the southern Brazilian continental shelf reveals the presence of four genera and nine species, including two newly described (Cytheropteron sudatlanticum sp. nov., Loxoreticulatum pulchrum sp. nov.) and two left in open nomenclature (Cytheropteron sp. and Kangarina sp.). All of these species are restricted to the southern part of the Southwest Atlantic Ocean and do not extend beyond the coast of Rio de Janeiro, Brazil. Three of these species (Oculocytheropteron micropunctatum, O. reticulatum, Omacropunctatum) extend beyond the southern limit of the Brazilian Province (36°S), while the others occur inside the limits of the Brazilian Province (36°S–22/21°S). The genus Loxoreticulatum, a well-known ostracod taxon from the Antarctic Peninsula, southern Argentina and Falkland (= Malvinas) Islands, is herein reported for the first time from offshore Brazil.  相似文献   

10.

Background  

Chromobacterium violaceum is a free-living bacterium able to survive under diverse environmental conditions. In this study we evaluate the genetic and physiological diversity of Chromobacterium sp. isolates from three Brazilian ecosystems: Brazilian Savannah (Cerrado), Atlantic Rain Forest and Amazon Rain Forest. We have analyzed the diversity with molecular approaches (16S rRNA gene sequences and amplified ribosomal DNA restriction analysis) and phenotypic surveys of antibiotic resistance and biochemistry profiles.  相似文献   

11.
The tomato red spider mite Tetranychus evansi Baker et Pritchard occurs on solanaceous plants, and causes serious damage to a variety of crops in Africa and Europe. In 2001 this species was also found in Japan, on nightshade (Solanum nigrum L.), and its invasion to solanaceous of agricultural importance is feasible. To evaluate its potential severity as a pest, the present study assessed the life-history parameters, such as the rate of development and the intrinsic rate of natural increase (r m), on S. nigrum for T. evansi collected on seven sites worldwide. Increasing temperatures between 15 and 32.5°C significantly increased the developmental rate of the seven strains while immature developmental duration was about the same at 32.5–40°C. The rate of egg-to-adult development [(% hatch) × (% survival)] exceeded 88% at temperatures between 15 and 37.5°C. The lower thermal thresholds (LT) were 11.9–12.5°C for both egg-to-adult and egg-to-egg development. The optimum developmental temperatures ranged from 36.7 to 43.8°C and the upper developmental threshold (UT) ranged from 45.2 to 59.4°C. The r m-values became higher with temperature increasing from 15 to 35°C. The r m-values at 25°C ranged from 0.265 to 0.277 which are relatively high for species of the genus Tetranychus. These results indicate that T. evansi after invasion into Japan has the potential to become a serious pest on solanaceous crops, just the same as in Africa and Europe.  相似文献   

12.
Vagrant Antarctic pinnipeds at Gough Island   总被引:1,自引:1,他引:0  
Opportunistic sightings of Antarctic fur seals Arctocephalus gazella and a leopard seal Hydrurga leptonyx at Gough Island (40°20′S, 09°54′W) in the South Atlantic Ocean represent the northernmost island records for vagrant Antarctic fur seals, and only the second for a vagrant leopard seal at Gough Island. Some ten different individual Antarctic fur seals were sighted on a single day, up to seven on a single beach. An overall total of 18 individuals were recorded over a 7-week period in October/November 2005, before the onset of the breeding (pupping) season of the resident population of Subantarctic fur seals Arctocephalus tropicalis. Most were immature, male and mostly in good condition (n = 11, 61%); one mature male and six putative females were also present. All had departed after 23 November, although only a fraction of the available beaches was searched.  相似文献   

13.
Life‐history traits of exotic species are important to understand the process involved in their settlement and their potential impact on native biodiversity. In this context, the seasonal density, the population structure and the reproductive patterns of exotic and native peracarid species of two natural marine environments of Southwestern Atlantic were studied in order to determine the traits that favour the invasion success of exotic species. Five samples, consisted of algal patches (0.20 × 0.20 m quadrants), were collected seasonally from 2016 to 2017 in two intertidal environments (La Estafeta and Cerro Avanzado). Both environments presented high richness of cryptogenic and exotic species (Tanais dulongii, Monocorophium insidiosum, Ampithoe valida, Melita palmata and Jassa marmorata), and only two native species were recorded (Apohyale grandicornis and Exosphaeroma lanceolatum). The comparison of life‐history traits suggested that the distribution, dominance and the highest densities of some exotic species are closely related to their continuous reproductive and recruitment periods, their capability to adapt their life‐history strategies to different environmental conditions and to a more efficient distribution of resources during reproduction; however, in native species, only A. grandicornis registered similar life‐history traits than exotic populations, suggesting that their distribution could be limited by a latitudinal gradient. We expect that these results provide essential information to understand the invasion pattern of exotic species and their potential impact on native biodiversity in Southwestern Atlantic.  相似文献   

14.
Sharks of the genus Rhizoprionodon are among the most important predators along the coastal marine ecosystems, and they represent an important economic resource for the small-scale fisheries. To properly manage and conserve exploited shark species, detailed analyses of their population structure are needed. To evaluate the gene flow and levels of the genetic diversity among populations of the Caribbean sharpnose shark R. porosus, we identified the nucleotide sequence based on collections (n = 321 specimens) from 10 different areas, including the Caribbean Sea and several locations along the entire Brazilian coast. The analysis of 802 nucleotides from the mitochondrial DNA control region revealed 53 distinct haplotypes. The majority of these haplotypes were restricted to their collection locales with a significant genetic structure detected among the overall populations (Φ ST  = 0.237, P < 0.0001). The data suggest a population division with two distinct management units in the western Atlantic. These management units are likely separated by the Equatorial Current. The strong population structure in R. porosus indicates that regional populations, if depleted, will not recover swiftly through immigration.  相似文献   

15.
Ipecac (Psychotria ipecacuanha) is a perennial, medicinal herb that grows in the understory of semi-deciduous tropical forests in the Neotropics. Ipecacs present a widely disjunct distribution, with two of its three ranges occurring in Brazil. The Amazonian populations are at least 1600 km from the nearest Atlantic populations. This work used ISSR markers to compare the genetic diversity and structure of populations from the two Brazilian ranges. Lower genetic diversity in Amazon populations (P = 60.11%, Hs = 0.18) and higher genetic diversity in Atlantic populations (P = 73.94%, Hs = 0.20) were detected. Differentiation between ranges were high (θ B = 0.6838, GST-B = 0.6665). AMOVA revealed that 65.3% of the total molecular variance can be attributed to regional differences between the two ranges. Principal coordinate analyses and cluster analyses organized ipecacs at either individual or population level into two exclusive groups that correspond each to one of the two disjunct ranges, without exception. The results do not support a scenario that postulates human-mediated, long-distance dispersal events as a plausible origin for the distribution of the Brazilian ipecacs, but indicate geographic isolation as a long-standing barrier to genetic exchange and connectivity among populations from different ranges. Conservation implications are discussed.  相似文献   

16.
The aim of this paper was to explore egg-laying areas of oviparous chondrichthyans occurring in the northern part of the Southwest Atlantic Ocean (36°S–41°S) at between 50 and 200 metres depth and the Mar del Plata Canyon (from 200 to 3447?m). A total of 515 capsules were collected corresponding to 10 species. Four species accounted for 87.6% of the total catch: Psammobatis normani, Bathyraja macloviana, Amblyraja doellojuradoi and Bathyraja brachyurops. The remaining corresponded to Schroederichthys bivius, Psammobatis rudis, Zearaja chilensis, Bathyraja albomaculata, Psammobatis lentiginosa and Bathyraja sp. Most hauls were monospecific and relatively few hauls contained four or five species (southern part of the area, in sites located at 75 and 94–105?m depth). No egg capsules were recorded between 1712?m and 3447?m. Highest densities (>3000 capsules/km2) were mainly found between 39°46.2′ and 40°29.9′S from 85 to 105?m and they were also recorded near the Mar del Plata Canyon at 37°59.7′S and at 852?m. The highest value recorded was 12,326 capsules/km2 (located at 40°18.9′S and 85.4?m). The highest densities for each of the most abundant species are discussed. The finding of high densities of egg cases near the Argentine shelf-break front indicates that many skate species use this area as a nursery site. The egg-laying areas explored here are the first reported sites of this kind in the Southwest Atlantic Ocean. Recognizing and protecting egg-laying habitats may be important steps to a long-term conservation of oviparous chondrichthyan populations.  相似文献   

17.
The changes in foliar concentrations of volatile terpenes in response to water stress, fertilization and temperature were analyzed in Pinus halepensis and Quercus ilex. The most abundant terpenes found in both species were α-pinene and Δ3-carene. β-Pinene and myrcene were also abundant in both species. P. halepensis concentrations were much greater than those of Q. ilex in agreement with the lack of storage in the latter species (15205.60 ± 1140.04 vs. 0.54 ± 0.08 μg g−1 [d.m.]). The drought treatment (reduction to 1/3 of full watering) significantly increased the total terpene concentrations in both species (54% in P. halepensis and 119% in Q. ilex). The fertilization treatment (addition of either 250 kg N ha−1 or 250 kg P ha−1 or both) had no significant effects on terpene foliar concentrations. The terpene concentrations increased from 0.25 μg g−1 [d.m.] at 30°C to 0.70 μg g−1 [d.m.] at 40°C in Q. ilex (the non-storing species) and from 2,240 μg g−1 [d.m.] at 30°C to 15,621 μg g−1 [d.m.] at 40°C in P. halepensis (the storing species). Both species presented negative relationship between terpene concentrations and relative water contents (RWC). The results of this study show that higher terpene concentrations can be expected in the warmer and drier conditions predicted for the next decades in the Mediterranean region.  相似文献   

18.
This paper presents the results of the first field study of the Brazilian endemic damselfish Stegastes rocasensis. Underwater data were collected at the Fernando de Noronha Archipelago (NE Brazil), where four sites were visually assayed for local territorial and feeding behaviors, as well as habitat use. S. rocasensis preferentially fed on turf and macroalgae, and during the afternoon period. Its territory size ranged from 0.26 to 13.86 m2 (1.61 ± 0.23 m2). Our findings suggest that adults preferably inhabit shallow, turf-rich areas, while sub-adults and juveniles occupy deeper areas with higher percent cover of invertebrates and hard corals, respectively. With regards to agonistic behaviors, pursuit of intruders was the most frequent reaction recorded (p < 0.001); the highest level of aggression was elicited by territorial herbivores (p < 0.001). Nevertheless, analysis of attacks elicited by different fish species within S. rocasensis’ territory showed that more attacks were launched on conspecifics than on other fish species.  相似文献   

19.
The vertical distribution of the richness, abundance, and composition of epiphytic bryophytes was studied in a matrix of fragmented habitats in the Brazilian Atlantic rainforest of the Murici Ecological Station (9°11′05″–9°16′48″ S, 35°45′20″–35°55′12″ W), northeastern Brazil. The aim was to compare the horizontal (between sites) and vertical (between phorophyte heights) turnover to test a hypothesis based on niche width vulnerability. There was a highly significant decreasing of richness accompanying the loss of habitat, and the most conserved fragment housed a total richness more than 10 times higher than the less conserved fragment. Epiphytes failed to colonize lower trunks (2.1–10 m) and higher zones in most of the non-conserved fragments; they were restricted to the base (0–2 m) and displayed a clear altered floristic composition. The species with restricted ecological amplitudes such as sun and shade tolerant taxa were more negatively affected by habitat loss than generalists. Although the mean richness of generalists decreased in non conserved fragments, the proportional contribution of this guild increased, proving that these taxa are the ones which persist in disturbed sites. The forest fragments capable of harboring rich epiphyte flora in the area studied are over 300 ha in size, which is far from being a common size among Brazilian Atlantic rainforest fragments. Hence, our results highlight the need of conserving the few large remnants in this ecosystem.  相似文献   

20.
Stolephorus teguhi sp. nov. is described from the holotype and 14 paratypes, 49–77 mm in standard length, collected from North Sulawesi, Indonesia. The species is characterized by having numerous gill rakers (31–35 + 41–46 = 72–82) and a short upper jaw, its posterior tip reaching to or extending slightly beyond the anterior margin of the preopercle. Stolephorus pacificus and S. multibranchus also have relatively numerous gill rakers for species of this genus (21–27 + 29–36 = 53–61 and 21–28 + 30–35 = 54–60, respectively), but counts for S. teguhi exceed those for the two species. Although S. advenus also has a short upper jaw similar to that of S. teguhi, the former has far fewer gill rakers (19 + 24 = 43) than the latter.  相似文献   

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