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1.
Four species of Mediorhynchus are identified from Australian birds. New locality records are given for Mediorhynchus alecturae (Johnston and Mawson, 1947) Golvan, 1962 and new host and locality records for M. corcoracis Johnston and Edmonds, 1951. Mediorhychus grandis has been reported from Australian hosts, but this record could not be verified. Two females from Acanthogenys rufogularis and the anterior portion of a single female from a "gull" had characters of proboscis armature, lemnisci, and eggs that precluded them being assigned to any of the presently known species of Mediorhynchus. Mediorhynchus colluricinclae n. sp. was found in pomatostomatids from South Australian localities. A high degree of host specificity is recorded for M. corcoracis and M. colluricinclae. Selection of specific dietary items may be one filter that influences the degree of host specificity encountered.  相似文献   

2.
A biogeographic and phylogenetic study of Cyrtandra (Gesneriaceae) in the Sundaland region (Borneo and Peninsular Malaysia) and the Philippines using nuclear ribosomal (ITS) DNA sequence data reveals a major division between the Cyrtandra floras of Sundaland and the Philippines. Palawan, the most westerly of the Philippine islands, emerges as an area of mixing between these two. The Bornean element in the Cyrtandra flora of Palawan (two species in our sample) appears to result from recent (i.e. Pleistocene) dispersal from Borneo. The remaining seven species sampled from Palawan are most closely related to those from elsewhere in the Philippines. However, the Palawan clade is sister to the other Philippine taxa, suggesting an ancient (possibly Pliocene) vicariance event. Huxley's line–a zoogeographic boundary placing Palawan and Borneo together–receives some support from this study as there is evidence of recent dispersal of Bornean flora into Palawan. However, in terms of more ancient biogeographic patterning of the region, Palawan has stronger links with the other Philippine islands.  相似文献   

3.
Aim Nearly 150 years ago, T. H. Huxley modified Wallace’s Line, including the island of Palawan as a component of the Asian biogeographic realm and separating it from the oceanic Philippines. Although Huxley recognized some characteristics of a transition between the regions, Palawan has since been regarded primarily as a peripheral component of the Sunda Shelf. However, several recent phylogenetic studies of Southeast Asian lineages document populations on Palawan to be closely related to taxa from the oceanic Philippines, apparently contradicting the biogeographic association of Palawan with the Sunda Shelf. In the light of recent evidence, we evaluate taxonomic and phylogenetic data in an attempt to identify the origin(s) of Palawan’s terrestrial vertebrate fauna. Location The Sunda Shelf and the Philippines. Methods We review distributional and phylogenetic data for populations of terrestrial vertebrates from Palawan. Using taxonomic data, we compare the number of Palawan taxa (species and genera) shared with the Sunda Shelf and oceanic Philippines. Among widespread lineages, we use phylogenetic data to identify the number of Palawan taxa with sister relationships to populations or species from the Sunda Shelf or oceanic Philippines. Results Although many terrestrial vertebrate taxa are shared between Palawan and the Sunda Shelf, an increasing number of species and populations are now recognized as close relatives of lineages from the oceanic Philippines. Among the 39 putative lineages included in molecular phylogenetic studies with sampling from the Sunda Shelf, Palawan and the oceanic Philippines, 17 of them reveal sister relationships between lineages from Palawan and the oceanic Philippines. Main conclusions Rather than a simple nested subset of Sunda Shelf populations, Palawan is best viewed as having played multiple biogeographic roles, including a young and old extension of the Sunda Shelf, a springboard to diversification in the oceanic Philippines, and a biogeographic component of the Philippine archipelago. Palawan has a long, complex geological history, which may explain this variation in pattern. Huxley originally noted transitional elements in Palawan’s fauna; we therefore suggest that his modification of Wallace’s Line should be recognized as a filter zone, reflecting both his original intent and available taxonomic and molecular evidence.  相似文献   

4.
《Comptes rendus biologies》2019,342(1-2):45-53
The study of an important collection of scorpions, belonging to the genus Chaerilus, recently collected from a cave in the Palawan Island, Philippines, allows the clarification of the identity of this population, often misidentified with Chaerilus chapmani Vachon & Lourenço, 1985 known from caves in the Gunong Mulu National Park in Sarawak (Borneo). Chaerilus agnellivanniorum sp. n. is described from the Puerto Princesa Underground River Cave in Palawan Island based on 14 specimens, males, females, and juveniles. The new species is totally distinct morphologically from Chaerilus chapmani, a true troglobitic species. Chaerilus agnellivanniorum sp. n. may also be a true troglobitic element, but with a less marked degree of regression for several characters. Some comments on the ecology of the new species and on regional biogeography of Borneo and Palawan islands are also proposed.  相似文献   

5.
A new species of Nepenthes L., N. attenboroughii (Nepenthaceae), from Palawan Island in the Philippines, is described and illustrated. It is restricted to rocky, ultramafic soils that comprise the summit region of Mount Victoria, Municipality of Narra, where it occurs in isolation from other members of the genus. On the basis of the morphological features, this new taxon appears to be related to both N. mira Jebb & Cheek of Palawan and N. rajah Hook.f. of Borneo. Its substantial size places it among the largest of known pitcher plants. The diagnostic morphological characters are discussed and an updated key is provided for a revised complex of Nepenthes species from the Palawan and North Borneo phytogeographical region. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 195–202.  相似文献   

6.
The taxonomy of treeshrews (Order Scandentia) has long been complicated by ambiguous morphological species boundaries, and the treeshrews of the Palawan faunal region of the Philippines are no exception. Four named forms in the genus Tupaia Raffles, 1821, have been described from four island groups based on subtle qualitative morphological characters, and as many as three distinct species have been recognized. A recent molecular phylogenetic study of relationships among Tupaia species suggests that the two currently-recognized treeshrew species from the Palawan faunal region diverged very recently relative to other sister-species divergences within the genus and may not represent species-level taxonomic entities. Here we review the taxonomic and biogeographic histories of the Tupaia taxa from this region. We also collected craniodental data from 133 skulls of all four named forms, representing five island populations, and conducted univariate and multivariate analyses on these data. Our morphometric results are consistent with molecular results, further suggesting that there is insufficient evidence to recognize T. moellendorffi Matschie, 1898, as a separate species from T. palawanensis Thomas, 1894. Our analyses also revealed a craniodentally divergent population from the island of Balabac, which has never been considered a distinct subspecies (or species) from the population on Palawan. These results have conservation implications for the island populations in our analyses, but additional surveys and molecular evidence will be required to fully assess conservation priorities for the treeshrews of the Palawan faunal region.  相似文献   

7.
Native wild pigs of the Philippines are now in grave danger of extinction. Study of available material indicates that three species are present: Sundaland Sus barbatus on Palawan, and two endemic species, Sus philippensis (with three subspecies, one of them here described as new) on Luzon, Mindanao, Basilan, Leyte, Samar, Catanduanes and Mindoro, and Sus cebifroms on Negros, debit and Panay. Specimens from Jolo. Masbale and Bohol presently remain unallocated to species, and may reflect the occurrence of hybridization.  相似文献   

8.
S. H. Tan  P. K. L. Ng 《Hydrobiologia》1998,379(1-3):93-96
A new genus and new species of terrestrial potamid crab ( Carpomon pomulum) is described from the island of Palawan in the Philippines. This new genus can easily be distinguished from all other Philippine potamids in its smooth and inflated carapace, no trace of an epibranchial tooth, extremely low postorbital cristae, and stout and twisted male first gonopod. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

9.
During an acanthocephalan epizootic at the Pittsburgh aviary, an intermediate host for Mediorhynchus orientalis was found for the first time and 2 new potential intermediate hosts for the genus Mediorhynchus were noted. The cockroaches Pycnoscelis surinamensis and Periplaneta americana were found infected with acanthellae and appear to be suitable intermediate hosts.  相似文献   

10.
The establishment of environmental management zones is an important strategy for biodiversity conservation. However, identifying and assigning appropriate zones is a challenging task that is critical to the management’s success. The Environmentally Critical Areas Network (ECAN) of the Palawan province is among the management strategies being implemented in the western Philippines. Under this strategy, natural resources needing the highest degree of protection are designated as core zones (CZ). Our study revisited this strategy to assess the current placement of the core zones with respect to species distributions and vegetation types. We conducted a series of field surveys in four municipalities of Palawan to assess the status of biodiversity. Gathered data was used to identify potential critical habitats by generating species distribution models and performing vegetation analysis using land satellite images. The placement of the CZ was evaluated using the identified critical habitats. Our assessments show that many Palawan endemic species persist despite increasing pressures from anthropogenic activities. We also found that a considerable extent of natural forest remains, generally confined in high elevations and steep terrains. The assessment of critical habitats and CZ revealed vital gaps in protection, suggesting that a revision is necessary to accommodate important habitats of threatened and endemic species. Overall, our study highlights the significance of integrating biodiversity data in improving conservation and management strategies, which has been overlooked in the current ECAN zones.  相似文献   

11.
Two new subgenera and eight new species of the subfamily Phalangopsinae are described from Sulawesi, Supiori, Mindoro, Palawan, Sumatra, and Cousin islands. Two former subgenera, Longizacla and Brevizacla, are considered as genera. The new synonymy for a subgenus of the genus Luzonogryllus is established. Diagnostic characters and systematic position of some taxa are discussed.  相似文献   

12.
Average size frequency distributions of Tridacna squamosa, T. gigas, Hippopus hippopus and H. porcellanus harvested from the Sulu Archipelago and Southern Palawan areas from 1978–1985 were derived from export records and a warehouse inventory of giant clam shells. Average species mortality rates (Z) were estimated and were used to approximate average fishing mortality rates (F) over the period 1978–1985. Crude estimates of exploitation rates (F/Z) indicate that populations of these species are already overexploited. These findings have serious implications in view of the fact that the Sulu Archipelago and Southern Palawan are thought to be the last strongholds of giant clams in Philippine waters.  相似文献   

13.

Background

The complex history of Southeast Asian islands has long been of interest to biogeographers. Dispersal and vicariance events in the Pleistocene have received the most attention, though recent studies suggest a potentially more ancient history to components of the terrestrial fauna. Among this fauna is the enigmatic archaeobatrachian frog genus Barbourula, which only occurs on the islands of Borneo and Palawan. We utilize this lineage to gain unique insight into the temporal history of lineage diversification in Southeast Asian islands.

Methodology/Principal Findings

Using mitochondrial and nuclear genetic data, multiple fossil calibration points, and likelihood and Bayesian methods, we estimate phylogenetic relationships and divergence times for Barbourula. We determine the sensitivity of focal divergence times to specific calibration points by jackknife approach in which each calibration point is excluded from analysis. We find that relevant divergence time estimates are robust to the exclusion of specific calibration points. Barbourula is recovered as a monophyletic lineage nested within a monophyletic Costata. Barbourula diverged from its sister taxon Bombina in the Paleogene and the two species of Barbourula diverged in the Late Miocene.

Conclusions/Significance

The divergences within Barbourula and between it and Bombina are surprisingly old and represent the oldest estimates for a cladogenetic event resulting in living taxa endemic to Southeast Asian islands. Moreover, these divergence time estimates are consistent with a new biogeographic scenario: the Palawan Ark Hypothesis. We suggest that components of Palawan''s terrestrial fauna might have “rafted” on emergent portions of the North Palawan Block during its migration from the Asian mainland to its present-day position near Borneo. Further, dispersal from Palawan to Borneo (rather than Borneo to Palawan) may explain the current day disjunct distribution of this ancient lineage.  相似文献   

14.
We collected 153 northern bobwhites (Colinus virginianus) over a 10-mo period from Tall Timbers Research Station near Tallahassee, Florida, USA. Five species of gastrointestinal helminths were encountered commonly (greater than 30% prevalence): Cyrnea colini, Raillietina cesticillus, R. colinia, Heterakis isolonche, and Trichostrongylus tenuis. Other helminths included Brachylaima sp., Rhabdometra odiosa, Mediorhynchus papillosis, Cheilospirura spinosa, Dispharynx nasuta, Gongylonema ingluvicola, and Tetrameres pattersoni. During the intervening 15 yr since the last year-round study of this population of birds, C. spinosa and T. pattersoni have declined markedly, and Strongyloides sp. probably has become extinct locally. Prevalence and intensity seem more likely to fluctuate in parasite species that have complex life cycles.  相似文献   

15.
Acid phosphatases (APases) play a role in the release of phosphate in organic complexes in soil. We investigated tissue- and isoform-specific responses of APases to phosphorus (P) deficiency in three rice genotypes; Dasan-byeo, Sobi-byeo, and Palawan. The levels of shoot APase activity per protein were similar in the three genotypes. They significantly decreased with P deprivation that was longer than seven days. Root APase activity per protein was two- to three-fold higher in Dasan than in Sobi and Palawan. In all genotypes the APase activity increased in P-deficient plants, but the increase was higher in Sobi and Palawan. After 21 days of P deprivation, secreted APase activity increased more than eight-fold in Dasan and two-fold in Sobi and Palawan. Isoform profiles of shoot and root APases were most diverse in Dasan. The activities of the major isoforms in P-deficient shoots decreased in all three genotypes. Depending on the genotypes, further increases in constitutive isoforms and new induction of one to four isoforms occurred in P-deficient roots. The results indicate that tissue and genotype differences in the response of APase to P deficiency are primarily facilitated by the different responses of the isoforms.  相似文献   

16.
The agamid lizardDraco volans from Palawan, Republic of the Philippines, was found to be parasitised by threePlasmodium species:P. draconis n. sp.,P. volans n. sp. andP. vastator, Laird 1960. BothP. draconis andP. volans, but notP. vastator, were also present inD. volans from Sarawak. The species are readily distinguished by schizont size, merozoite number, and gametocyte size and shape.P. volans has schizonts approximately one-half the size of those ofP. draconis and produces 4–6 merozoites in comparison to 4–16 in the larger species. Gametocytes of both new species are predominantly oval in the Palawan sample and elongate in that from Sarawak.P. draconis gametocytes are approximately twice the size ofP. volans gametocytes, but on average no more than one-half the size of gametocytes ofP. vastator.  相似文献   

17.
Limited quantitative research has been conducted on coral disease in the Philippines and baseline data are much needed. Field surveys for prevalence and distribution patterns were conducted from November 2002 to August 2003. Sites included the islands of Negros, Cebu, Siquijor, Panglao, Olango, Sumilon, Bantayan, Pescador, Balicassag and Palawan. In 154 belt transects, 10 026 Porites colonies were examined at 28 sites covering 3080 m2. Two syndromes, Porites ulcerative white spot (PUWS) and coral tumors, occurred at high prevalence. Tumors as high as 39.1% occurred among massive Porites, and PUWS was as high as 53.7% among massive and branching Porites. In 8 mo, 116 tagged colonies showed slow progression and low mortality. Along a 41 km human impact gradient centered on Dumaguete City (Negros), 15 sites were examined. Correlation analyses linked higher disease prevalence to anthropogenic influence (Spearman's rank correlation coefficient [r(s)] = -0.54, p = 0.04 for tumors and r(s) = -0.69, p = 0.005 for PUWS). In most sites disease prevalence was lower than in the sites near Dumaguete. High PUWS prevalence near uninhabited Sumilon Island appeared to be linked to the highly diseased reefs near Dumaguete City due to transmission of disease along a cross-shelf front formed between the Ta?on Strait and Bohol Sea. Other observations included 12 potential new host species for PUWS (4 new genera and 1 octocorallia) and 5 likely new hosts for black band disease (BBD) in the Philippines, and a relatively high prevalence (7.8%) of BBD in 1 site in western Palawan.  相似文献   

18.
Aim We examine the genetic diversity within the lizard genus Gekko in the Philippine islands to understand the role of geography and geological history in shaping species diversity in this group. We test multiple biogeographical hypotheses of species relationships, including the recently proposed Palawan Ark Hypothesis. Location Southeast Asia and the Philippines. Methods Samples of all island endemic and widespread Philippine Gekko species were collected and sequenced for one mitochondrial gene (NADH dehydrogenase subunit 2) and one nuclear gene (phosducin). We used maximum likelihood and Bayesian phylogenetic methods to derive the phylogeny. Divergence time analyses were used to estimate the time tree of Philippine Gekko in order to test biogeographical predictions of species relationships. The phylogenetic trees from the posterior distribution of the Bayesian analyses were used for testing biogeographical hypotheses. Haplotype networks were created for the widespread species Gekko mindorensis to explore genetic variation within recently divergent clades. Results Both maximum likelihood and Bayesian phylogenetic analyses indicated that Philippine Gekko species are a diverse clade with a long history in the archipelago. Ancestral range reconstruction and divergence time analyses suggest a Palawan microcontinental origin for this clade, coinciding with Palawan’s separation from Asia beginning 30 Ma, with subsequent diversification in the oceanic Philippine islands. The widespread species G. mindorensis and G. monarchus diversified in the late Miocene/early Pliocene and are potentially complexes of numerous undescribed species. Main conclusions The view of the Philippine islands as a ‘fringing archipelago’ does not explain the pattern of species diversity in the genus Gekko. Philippine Gekko species have diversified within the archipelago over millions of years of isolation, forming a large diverse group of endemic species. Furthermore, the Philippine radiation of gekkonid lizards demonstrates biogeographical patterns most consistent with stochastic colonization followed by in situ diversification. Our results reveal the need to consider deeper time geological processes and their potential role in the evolution of some Philippine terrestrial organisms.  相似文献   

19.
Allelic diversity of the Plasmodium falciparum merozoite surface protein 1 gene (msp1) is mainly generated by meiotic recombination at the mosquito stage. We investigated recombination-based allelic diversity of msp1 in a P. falciparum population from Palawan Island, the Philippines, where malaria transmission is moderate. We identified the 5' recombinant types, 3' sequence types and msp1 haplotypes (unique combinations of 5' recombinant type and 3' sequence type), and compared them with those of P. falciparum from the Solomon Islands, where malaria transmission is high. The mean number of 5' recombinant types per patient in Palawan was 1.44, which is comparable to the number for the Solomon Islands (1.41). The Palawan parasite population had 15 msp1 haplotypes, whereas the Solomon Islands population had only 8 haplotypes. The Palawan population showed strong linkage disequilibrium between polymorphic blocks/sites within msp1, which is comparable to the results for the Solomon Islands. These findings support our hypothesis that the extent of allelic diversity of msp1 is determined not only by the transmission intensity but also by the number of msp1 alleles prevalent in the local parasite population and the extent of mixed-allele infections. Contribution of a high prevalence of the chloroquine (CQ)-sensitive allele of P. falciparum CQ resistance transporter (pfcrt) to the relatively high msp1 diversity in the Palawan population is discussed.  相似文献   

20.
Although recent molecular studies have clarified the phylogeny of mongooses, the systematics of the Southeast Asian species was incomplete as the collared mongoose Urva semitorquata and some debatable taxa (Hose's mongoose, Palawan mongoose) were missing in the analyses. We sequenced three mitochondrial (cytochrome b, ND2, control region) and one nuclear (beta‐fibrinogen intron 7) fragments of the Southeast Asian mongooses to clarify the systematic position of the different species and populations occurring in this region. Our results showed that the collared mongoose is closely related to the crab‐eating mongoose Urva urva, these two species forming a sister‐group to the short‐tailed mongoose Urva brachyura. Despite Sumatran collared mongooses having a peculiar orange phenotype, we showed that they exhibited very little genetic divergence to individuals from Borneo. In contrast, the populations of the short‐tailed mongoose from Borneo were strongly divergent to those from Peninsular Malaysia and Sumatra, and these might represent separate species. Within the crab‐eating mongoose, we observed little geographical genetic structure. Our study suggests that Hose's mongoose is not a valid species. The Palawan mongooses did not cluster with the other populations of the short‐tailed mongoose; they were closer to the collared mongoose and should be included in this species. © 2014 The Linnean Society of London  相似文献   

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