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1.
A freshwater fish Roeboides loftini n.sp. is described from the Río Coclé del Norte drainage of the Atlantic versant of Panamá. The new species differs from other species of the Roeboides guatemalensis-group by the number of perforated scales on the lateral line (83-100), body depth (31.8-36.1%), predorsal distance (49.1-51.9%) and the shape of the humeral spot.  相似文献   

2.
We report the comparative proteomic characterization of the venoms of two related neotropical arboreal pitvipers from Costa Rica of the genus Bothriechis, B. lateralis (side-striped palm pit viper) and B. schlegelii (eyelash pit viper). The crude venoms were fractionated by reverse-phase HPLC, followed by analysis of each chromatographic fraction by SDS-PAGE, N-terminal sequencing, MALDI-TOF mass fingerprinting, and collision-induced dissociation tandem mass spectrometry of tryptic peptides. The venom proteomes of B. lateralis and B. schlegelii comprise similar number of distinct proteins belonging, respectively, to 8 and 7 protein families. The two Bothriechis venoms contain bradykinin-potentiating peptides (BPPs), and proteins from the phospholipase A 2 (PLA 2), serine proteinase, l-amino acid oxidase (LAO), cysteine-rich secretory protein (CRISP), and Zn (2+)-dependent metalloproteinase (SVMP) families, albeit each species exhibit different relative abundances. Each venom also contains unique components, for example, snake venom vascular endothelial growth factor (svVEGF) and C-type lectin-like molecules in B. lateralis, and Kazal-type serine proteinase inhibitor-like proteins in B. schlegelii. Using a similarity coefficient, we estimate that the similarity of the venom proteins between the two Bothriechis taxa may be <10%, indicating a high divergence in their venom compositions, in spite of the fact that both species have evolved to adapt to arboreal habits. The major toxin families of B. lateralis and B. schlegelii are SVMP (55% of the total venom proteins) and PLA 2 (44%), respectively. Their different venom toxin compositions provide clues for rationalizing the distinct signs of envenomation caused by B. schlegelii and B. lateralis. An antivenomic study of the immunoreactivity of the Instituto Clodomiro Picado (ICP) polyvalent antivenom toward Bothriechis venoms revealed that l-amino acid oxidase and SVMPs represent the major antigenic protein species in both venoms. Our results provide a ground for rationalizing the reported protection of the ICP polyvalent antivenom against the hemorrhagic, coagulant, defibrinating, caseinolytic and fibrin(ogen)olytic activities of Bothriechis ( schlegelii, lateralis) venoms. However, these analyses also evidenced the limited recognition capability of the polyvalent antivenom toward a number of Bothriechis venom components, predominantly BPPs, svVEGF, Kazal-type inhibitors, some PLA 2 proteins, some serine proteinases, and CRISP molecules.  相似文献   

3.
Vadell EM  Cavender JC 《Mycologia》2007,99(1):112-124
Thirteen new species and varieties of dictyostelid cellular slime molds (csm) were isolated from soils of the Atlantic Subtropical Rain Forest at the Iguazú Falls, Northeastern Misiones Province, Argentina. Seven new species are described herein, one of them is a Polysphondylium, while the rest of the species belong to the genus Dictyostelium. Also, six taxa are new varieties of Dictyostelium and Acytostelium, which will be reported later. Fourteen Northern Hemisphere (Tikal) species have also been isolated from Iguazú soils, some of them new records for Southern South America. This csm community, when compared with others from forests of the Northern Hemisphere, particularly Tikal, Guatemala, give some insight into a possibly different evolutionary history and/or natural selection in the two areas.  相似文献   

4.
5.
The systematics and distribution of the cirrate octopod genus Grimpoteuthis in the north-east Atlantic are reviewed. Three new species are described and Grimpoteuthis wuelkeri (Grimpe, 1920) is redescribed. A new generic diagnosis is proposed. Five species of Grimpoteuthis are recognized in the north-east Atlantic. The type species, G. umbellata (Fisher, 1883) is known only from the type specimen, which is in such poor condition that comparison with recently captured material was not possible. G. wuelkeri is a large, slope species, caught between 1600 m and 2200 m in the north-east and north-west Atlantic. Of the three new species, both G. boylei and G. challengeri are large abyssal species. G. boylei is found in the north-east Atlantic at the Porcupine Abyssal Plain (PAP) and the Madeira Abyssal Plain and may be found at abyssal depths throughout the north-east Atlantic. G. challengeri is known from the PAP, with a single specimen from the north-west Atlantic. G. discoveryi is a small, lower slope and abyssal species found in the north-east Atlantic. The Grimpoteuthis species can be separated based on shell form, presence of a radula and posterior salivary glands, arrangement of suckers and cirri and gill morphology. Two species, G. megaptera Verrill and G. plena Verrill, have been described from the north-west Atlantic, but the types are either lost ( G. megaptera ) or in poor condition ( G. plena ), hindering comparisons. Material examined from the north-west Atlantic included G. wuelkeri , G. challengeri and at least two other species.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139 , 93−127.  相似文献   

6.
A new species of Araceae, Rhodospatha arborescens, was found in two preservation areas in Minas Gerais state, Brazil, Caratinga Biological Station and Rio Doce State Park, both located in a semideciduous seasonal forest (Interior Atlantic Rainforest). The new species is helophytic and arborescent. It is described, illustrated, and compared with Rhodospatha species that occur in the Atlantic Rainforest, using a dichotomous key. Information is also presented on the geographic distribution, ecology, and phenology these species.  相似文献   

7.
Robert D. Dorn 《Brittonia》1998,50(2):193-210
Salix section Longifoliae occurs from Alaska to Guatemala and from the Atlantic to the Pacific. Nine taxa are here accepted as five species with one of the species including two subspecies and four varieties. the holotype of Salix taxifolia Humb., Bonpl. & Kunth represents the same taxon as the lectotype of Salix microphylla Schltdl. & Cham. Material recently called S. taxifolia is given a new name. Salix exilifolia Dorn. The name Salix fluviatilis Nutt is considered to be synonymous with S. melanopsis Nutt. One new variety is described and two new combinations are made under Salix exigua Nutt.  相似文献   

8.
Members of the Cryptotis goldmani group of small‐eared shrews (Mammalia, Soricomorpha, Soricidae) represent a clade within the genus that is characterized by modifications of the forelimb that include broadened forefeet, elongated and broadened foreclaws, and massive humeri with enlarged processes. These modifications are consistent with greater adaptation to their semifossorial habits than other members of the genus. The species in this group occur discontinuously in temperate highlands from southern Tamaulipas, Mexico, to Honduras. In Guatemala, there are three species: the relatively widespread Cryptotis goodwini and two species (Cryptotis lacertosus, Cryptotis mam) endemic to highland forests in the Sierra de los Cuchumatanes of western Guatemala. Ongoing studies focusing on the relationships of variation in cranial and postcranial skeletal morphology have revealed a fourth species from remnant cloud forest in the Sierra de Yalijux, central Guatemala. In this paper, I describe this new species and characterize its morphology relative to other species in the C. goldmani group and to other species of Cryptotis in Guatemala. In addition, I summarize available details of its habitat and ecology. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1267–1288.  相似文献   

9.
The geographical and vertical distribution of Boroecia borealis was studied based on literature data and materials collected by Soviet and Russian expeditions in the Arctic Ocean and adjacent waters of the Atlantic during the period from 1929 to 1993. In the region of study, this species occurs at a temperature from 0.5 to 17.7°C. In the Arctic basin, B. borealis is predominantly found in the warm deep Atlantic layer. The central Arctic region is not a zone of exclusion of this species, but is a part of the species’ range, where its apparently dependent populations occur. In the northern Atlantic, B. borealis can reach into the low latitudes as far as 30°N.  相似文献   

10.
Collecting reef-fish specimens using a manned submersible diving to 300 m off Curaçao, southern Caribbean, is resulting in the discovery of numerous new fish species. The new Liopropoma sea bass described here differs from other western Atlantic members of the genus in having VIII, 13 dorsal-fin rays; a moderately indented dorsal-fin margin; a yellow-orange stripe along the entire upper lip; a series of approximately 13 white, chevron-shaped markings on the ventral portion of the trunk; and a reddish-black blotch on the tip of the lower caudal-fin lobe. The new species, with predominantly yellow body and fins, closely resembles the other two “golden basses” found together with it at Curaçao: L. aberrans and L. olneyi. It also shares morphological features with the other western Atlantic liopropomin genus, Bathyanthias. Preliminary phylogenetic data suggest that western Atlantic liopropomins, including Bathyanthias, are monophyletic with respect to Indo-Pacific Liopropoma, and that Bathyanthias is nested within Liopropoma, indicating a need for further study of the generic limits of Liopropoma. The phylogenetic data also suggest that western Atlantic liopropomins comprise three monophyletic clades that have overlapping depth distributions but different depth maxima (3–135 m, 30–150 m, 133–411 m). The new species has the deepest depth range (182–241 m) of any known western Atlantic Liopropoma species. Both allopatric and depth-mediated ecological speciation may have contributed to the evolution of western Atlantic Liopropomini.  相似文献   

11.
Cano EB  Schuster JC 《ZooKeys》2012,(194):81-87
Oileus gasparilomisp. n. is described from nine specimens from the mountains of Quiché in Guatemala, from cloud forest at 1795 m elevation. This represents the second species of the genus for Guatemala, differing from the closely related Mexican species Oileus rimator (Truqui) in having a straight anterior clypeal border, the postocular sulcus divided by a keel and the pronotum almost straight (not clearly bilobed). A key to the species of Oileus is given.  相似文献   

12.
Listroscelidinae (Orthoptera: Tettigoniidae) are insectivorous Pantropical katydids whose taxonomy presents a long history of controversy, with several genera incertae sedis. This work focused on species occurring in the Brazilian Atlantic Forest, one of the world''s most threatened biomes. We examined material deposited in scientific collections and visited 15 conservation units from Rio de Janeiro to southern Bahia between November 2011 and January 2012, catching 104 specimens from 10 conservation units. Based on morphological and molecular data we redefined Listroscelidini, adding a new tribe, new genus and eight new species to the subfamily. Using morphological analysis, we redescribed and added new geographic records for six species, synonymized two species and built a provisional identification key for the Atlantic Forest Listroscelidinae. Molecular results suggest two new species and a new genus to be described, possibly by the fission of the genus Hamayulus. We also proposed a 500 bp region in the final portion of the COI to be used as a molecular barcode. Our data suggest that the Atlantic Forest Listroscelidinae are seriously endangered, because they occur in highly preserved forest remnants, show high rates of endemism and have a narrow geographic distribution. Based on our results, we suggest future collection efforts must take into account the molecular barcode data to accelerate species recognition.  相似文献   

13.
Seguin  Gérard  Errhif  Ahmed  Dallot  Serge 《Hydrobiologia》1994,(1):369-377
During the oceanographic campaign, ALMOFRONT I (April 24–May 26, 1991) a total of 50 vertical zooplankton hauls was carried out in the Alboran Sea using a triple net. Leg A (18 stations; 18 hauls) described a widely spaced grid in the region of the Atlantic current and some northern eddies, while Leg B (16 stations; 32 hauls, 6 hydrodynamically characterized sites sampled during a two day period) covered a more restricted area in the frontal zone. Ninety-one species of copepods were found in 100 samples collected by either 200 µm or 500 µm mesh size nets, including 32 genera and 26 families. Copepod abundance, structure indexes (species richness, evenness, Shannon species diversity index, standardized for unequal sample counts) and species abundance patterns (as rank-frequency diagrams) are presented and compared among the sites of leg-B. Copepod abundance was found to be the highest in the more productive sites of the Atlantic current. Structure indexes values and the changing shape of rank-frequency diagrams give a coherent view of the ecological succession stages of the copepod community. Juvenile stage (1) develops from the Atlantic divergence zone, left side of the jet. More mature stages (1 and 2) occur on the right side of the jet influenced by cross frontal flow. Both abundance and structure indexes decrease within an anticyclonic gyre south to the current. A situation more influenced by oligotrophic conditions was observed in a Mediterranean anticyclonic gyre north of the current. The importance of lateral displacement and meandering of the Atlantic current across the Alboran Sea to the community structure is discussed.  相似文献   

14.
The deep sea is a vast and essentially continuous environment with few obvious barriers to gene flow. How populations diverge and new species form in this remote ecosystem is poorly understood. Phylogeographical analyses have begun to provide some insight into evolutionary processes at bathyal depths (<3000 m), but much less is known about evolution in the more extensive abyssal regions (>3000 m). Here, we quantify geographical and bathymetric patterns of genetic variation (16S rRNA mitochondrial gene) in the protobranch bivalve Ledella ultima, which is one of the most abundant abyssal protobranchs in the Atlantic with a broad bathymetric and geographical distribution. We found virtually no genetic divergence within basins and only modest divergence among eight Atlantic basins. Levels of population divergence among basins were related to geographical distance and were greater in the South Atlantic than in the North Atlantic. Ocean‐wide patterns of genetic variation indicate basin‐wide divergence that exceeds what others have found for abyssal organisms, but considerably less than bathyal protobranchs across similar geographical scales. Populations on either side of the Mid‐Atlantic Ridge in the North Atlantic differed, suggesting the Ridge might impede gene flow at abyssal depths. Our results indicate that abyssal populations might be quite large (cosmopolitan), exhibit only modest genetic structure and probably provide little potential for the formation of new species.  相似文献   

15.
Based on materials obtained during Soviet and Russian expeditions to the Arctic basin and adjacent Atlantic waters during the period from 1929–1993, as well as data from the literature, we examined the distribution range of the common deep-sea ostracod Boroecia maxima. This species occurs throughout the pelagic water column (down to 3000 m depth and below) and prefers low water temperatures (surface Arctic and intermediate water masses). During the year, at all depths, the ratio between age groups of B. maxima remains virtually unchanged. Breeding apparently continues year-round. During the polar night, B. maxima makes no migration into warm Atlantic water, where wintering predatory zooplankton occur in large numbers, and thus avoids grazing pressure.  相似文献   

16.
To determine the spatial dynamics of Neotropical lotic insect species, specimens were collected from 41 streams on the eastern and western flanks of the Andes Mountains in Ecuador. We examined the manner in which taxonomic richness and composition differed with elevation, latitude, and versant. Statistical analyses were limited to 5 families (Ephemeroptera: Baetidae, Leptohyphidae, Oligoneuriidae; Heteroptera: Naucoridae; Coleoptera: Elmidae), comprising 32 genera and 85 species, for which identifications or morphospecies assignments were reliable. Assessment of taxonomic diversity was based on the richness of genera and species at each site. In addition, each site was characterized by species richness within each of 4 families with more than 10 species. The effects of versant and transect on composition and structure were family‐specific. Mean site differences between versants in elmid richness at generic and specific levels depended on transect. Only baetid richness was affected by versant and transect in a consistent manner. Variation among sites in composition based on all genera and species was captured using multidimensional scaling (MDS). Subsequent MANOVAs based on scores from MDS axes revealed that differences between versants were much stronger in the southern transect, although transects differed from each other at specific and generic levels. A Jaccard's similarity matrix was computed for each family to reflect the spatial organization of taxonomic composition. Mesogeographic patterns of species composition for each of the four families were correlated (Mantel analysis) at both the regional level and at the level of the entire study area. At the regional level, the only pair of families to exhibit correlated patterns of species composition was elmids and naucorids in the southwestern region. The pattern of species composition for each family was correlated with the patterns for one or more other families at the level of the entire study area. Thus, spatial dynamics of species composition was similar for the families examined, suggesting that the Andes exert a consistent influence on species distributions within families, regardless of ordinal affiliation. At a local scale, however, the way in which taxonomic composition changed with latitude and versant was family‐specific. Mayflies, the most vagile of the taxa studied, had the highest percentage of species overlap between versants. Of three genera of Naucoridae collected, species of Ambrysus, of probable Mexican origin, were found only on the eastern versant, corroborating other evidence that the genus is recent in South America. Moreover, dispersion by Ambrysus across the Andes Mountains may not have occurred, as it has for Cryphocricos and Limnocoris, which are of probable South American origin.  相似文献   

17.
The wreckfish Polyprion americanus , a large [>1 m total length ( L T)] demersal teleost, is distributed globally in temperate waters, including both sides of the North and South Atlantic Oceans, the Mediterranean, the western South Pacific, and the southern Indian Ocean. Wreckfish spawn off the south-eastern U.S. on an area of the Blake Plateau (the Charleston Bump) characterized by an extensive ridge having approximately 100 m relief, in 450–600 m depths. Juvenile wreckfish (<60 cm L T) are pelagic and, in the North Atlantic, are not reported from the Blake Plateau fishing area, but occur in by-catch and fishery landings in the eastern Atlantic. Analysis of nine restriction fragment length profiles from a PCR-amplified fragment (∼1.5 kb) of the ND1 mitochondrial gene indicated no stock separation between eastern North Atlantic (Azores, Majorca, Madeira), and western North Atlantic (Blake Plateau) wreckfish. Restriction site differences separate western South Atlantic wreckfish from the North Atlantic; however, South Atlantic wreckfish share restriction-site similarities with western Pacific wreckfish that are not shared with North Atlantic wreckfish. North Atlantic circulation provides a mechanism for a long-lived pelagic stage to be dispersed from Blake Plateau spawning grounds to the eastern North Atlantic. Global circulation patterns may explain both the dispersal of mtDNA haplotypes and the disjunct distribution of wreckfish body lengths in a temperate, deep-water vagile species with an extended pelagic juvenile stage such as wreckfish.  相似文献   

18.
Triatoma nitida was found in 14 (0.4%) out of 3,726 houses located in six departments across Guatemala, which were surveyed from 1994 to 1998 by the man-hour collection method. Compared to previous information, the distribution of T. nitida in Guatemala has increased from five to nine departments; the species is present in mild climates at altitudes from 960 to 1,500 m. Fourteen percent of the intradomestic T. nitida were infected with Trypanosoma cruzi. The species was often found in conjunction with other triatomines (T. dimidiata and Rhodnius prolixus). The domestic and peridomestic presence of T. nitida in Guatemala was rare, but occasionally this species was colonizing human-made constructions. T. nitida appears to have a low importance as Chagas disease vector in Guatemala, as indicated by its scarce presence in the domestic habitats and defecation patterns. However, it clearly has potential to become a Chagas vector so we recommend an on-going study of the intradomestic presence of T. nitida following the control programs in Guatemala. Morphometric analysis of 47 T. nitida males from three localities showed quantitative differences between the populations, which indicates that geographic distance is an important factor in the structuring of T. nitida populations.  相似文献   

19.
One hundred and eighty-two new specimens of Parabrotula and 52 Leucobrotula are reported. Generic separation is confirmed. although premaxillary dentition no longer distinguishes the two. Two species of Parabrotula (one yet to be described) and one of Leucobrotula are strongly indicated from meristic data. Breeding biology is considered, with comment upon sexual dimorphism in size, size at maturity and possible breeding period. Parabrotulu plagiophthalmus Zugmayer, 1911 is shown to be a midwater non-migrant species (range 76@1500 m) with a temperature preference in the eastern North Atlantic of 9.0–5.0° C. Leucobrotulu udipatus Koefoed, 1952 exhibits a depth range of 61–1290 m and a temperature range of 9.0–4.2° C. Geographically it is evidently restricted to the North Atlantic and endemic to the eastern side. Most specimens were caught pelagically in the northwest African upwelling area in slope waters. Parabrotulaplagiophthalnius is distributed worldwide, although 89% came from the eastern North Atlantic.  相似文献   

20.
The systematics of the eelpout genus Bothrocara Bean 1890 is reviewed on the basis of 941 specimens. Eight mostly eurybathic, demersal species are recognized, distributed mainly along the continental slopes of the North and South Pacific oceans, with one species entering the South Atlantic. Distributions are: B. brunneum ranges from the Sea of Okhotsk to the Gulf of Panama at depths of 199–1,829 m; B. elongatum ranges from the Gulf of Panama to Chile at depths of 720–1,866 m; B. hollandi ranges from the Sea of Japan to the southeastern Bering Sea at depths of 150–1,980 m; B. molle ranges from the western Bering Sea to the South Atlantic at depths of 106–2,688 m; B. nyx is known only from the eastern Bering Sea at depths of 790–1,508 m; B. pusillum ranges from the northern Bering Sea to British Columbia, Canada, at depths of 55–642 m; B. tanakae is found along the northern coasts of Honshu and Hokkaido islands, Japan, at depths of 274–892 m; B. zestum ranges from the Izu Islands, Japan, and central Honshu, Japan, to the Gulf of Alaska at depths of 199–1,620 m (an unidentifiable specimen from off Taiwan may be B. zestum). The species are distinguished from one another mainly on the basis of head pore patterns, gill raker morphology, coloration and various meristic and morphometric values. A determination key to the species is provided.  相似文献   

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