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The two pentastomid species currently included in the genusLeiperia Sambon, 1922 (family Sebekidae Fain, 1961) are re-assessed. Measurements of chitinous structures, notably the hooks, fulcra and oral cadre of three adult females of the otherwise well-characterised speciesL. cincinnalis Sambon, 1922, from the bronchi of the Nile crocodileCrocodylus niloticus, exhibit a degree of variation that is usual in pentastomid morphometrics. Similar measurements of six nymphs from the aorta and heart of two other crocodiles, although equally variable, do not differentiate these from infective nymphs removed from cysts within the body cavity of a South African fish (Pelamatachromis robustus) intermediate host. Adult females of another species,L. australiensis n. sp., from the bronchi of the Indopacific crocodileCrocodylus porosus from Northern Australia are described. Females (N=3) are smaller and more slender than their African counterparts, and their chitinous structures, although equally variable, are correspondingly smaller. A mature male, from the lung of Johnston's crocodileC. johnsoni, is also allocated to this species because the ranges and diet of the two crocodilian hosts overlap. Also, this zone of syntopy is sufficient to maintain populations of two other species belonging to the family Sebekidae (Sebekia spp.) in both hosts. This male is the first of the genusLeiperia to be fully described, and its copulatory spicules are quite distinctive. Three other immature specimens ofL. australiensis from the lung, or near to the lung, of the definitive host are also described. In the light of these findings the literature is re-appraised, and it is evident that at least two moreLeiperia spp. exist in South America, and that presently these are known only as nymphs. The existing South American species,L. gracilis Heymons & Vitzthum, 1935 (=Pentastoma gracile Diesing, 1835) was established only on the basis of immature or nymphal forms, almost certainly encompassing several genera. Despite claims to the contrary in the literature, this ‘species’ should be regarded as aspecies inquirenda. Aspects of the life-cycle ofLeiperia spp., from the infective stage in fish and the subsequent instars, are also discussed.  相似文献   

3.
The pentastomid genus Alofia Giglioli, 1922 (Porocephalida: Sebekidae), which is exclusively parasitic in the bronchioles of crocodiles, is reviewed. The type-species of the taxon, A. ginae Giglioli, 1922 from an unknown host allegedly taken in Samoa, had very distinctive, fine hooks with long slender blades bent at right angles. I describe a single female with identical hooks from the Philippines which was almost certainly derived from the marine crocodile Crocodylus porosus. This same host harboured two specimens of another Alofia species, tentatively identified as A. merki Giglioli, 1922, a species originally described with A. ginae (and, in all probability, from the same (unknown) host). Additional male and female specimens of A. merki, from several specimens of Australian C. porosus, re-affirm the characteristics of this species. Another new Alofia species, A. simpsoni, from an unknown host in Ghana, is established from measurements of two slide-mounted specimens (previously labelled Sebekia) from The Natural History Museum. There can be little doubt that its host is also a crocodile. A new monotypic genus Selfia is described, based on a type-series of 14 female and one male pentastomids dissected from the bronchioles of five specimens of C. porosus, all taken in Australia. Of the genera comprising the family Sebekidae (Alofia, Sebekia, Diesingia and Leiperia) Selfia is closest to the first, and its main diagnostic characteristics include a massive Alofia-like body, but with a markedly tapered, bluntly-rounded tail, and small, smooth ‘linear’ hooks with minute blades. The rear part of the anterior hooks are enveloped by a soft, cowl-like extension to the fulcrum, covered by small spines. The oral cadre is not U-shaped as in Alofia, but is more like that of Sebekia, whereas by contrast the male copulatory spicules of Selfia porosus and Alofia spp. are virtually identical, except in size. One previously described Alofia sp. from South American crocodilians is well characterized and valid, but two others are considered species inquirendae.  相似文献   

4.
Microsatellite DNA loci have emerged as the dominant genetic tool for addressing questions associated with genetic diversity in many wildlife species, including crocodilians. Despite their usefulness, their isolation and development can be costly, as well as labour intensive, limiting their wider use in many crocodilian species. In this study, we investigate the cross-species amplification success of 82 existing microsatellites previously isolated for the saltwater crocodile (Crocodylus porosus) in 18 non-target crocodilian species; Alligator sinensis, Caiman crocodylus, Caiman latirostris, Caiman yacare, Melanosuchus niger, Paleosuchus palpebrosus, Crocodylus acutus, Mecistops cataphractus, Crocodylus intermedius, Crocodylus johnstoni, Crocodylus mindorensis, Crocodylus moreletii, Crocodylus niloticus, Crocodylus novaeguineae, Crocodylus palustis, Crocodylus rhombifer, Crocodylus siamensis, and Osteolaemus tetraspis. Our results show a high level of microsatellites cross-amplification making available polymorphic markers for a range of crocodilian species previously lacking informative genetic markers.  相似文献   

5.
Invasive species can have dramatic and detrimental effects on native species, and the magnitude of these effects can be mediated by a plethora of factors. One way to identify mediating factors is by comparing attributes of natural systems in species with heterogeneity of responses to the invasive species. This method first requires quantifying impacts in different habitats, ecosystems or geographic locations. We used a long-term, before-and-after study to quantify the impacts of the invasive and toxic cane toad (Rhinella marina) on two predators in a highly modified ecosystem: an irrigation channel in an agricultural landscape. Survey counts spanning 8 years indicated a severe population-level decline of 84 % in Merten’s Water Monitor (Varanus mertensi) that was coincident with the arrival of cane toads. The impact of cane toads on V. mertensi was similar to that found in other studies in other habitats, suggesting that cane toads severely impact V. mertensi populations, regardless of habitat type or geographic location. In contrast, a decline was not detected in the Freshwater Crocodile (Crocodylus johnstoni). There is now clear evidence that some C. johnstoni populations are vulnerable to cane toads, while others are not. Our results reinforce the need for the replication of impact studies within and among species; predicting impacts based on single studies could lead to overgeneralizations and potential mismanagement.  相似文献   

6.
The following rodents and marsupials from the Western Highlands of Papua New Guinea have been examined for helminths: Anisomys imitator, Melomys spp., Pogonomelomys ruemmleri, Rattus spp., Echymipera kalubu and Peroryctes raffrayanus. Two new species and a number of new host records are reported. Echinostoma echymiperae n. sp., a digenean from the intestine of Echymipera kalubu, is characterised by the number of collar spines, the body armature and the shape and position of the gonads. Vampirolepis peroryctis n. sp., a cestode from the intestine of Peroryctes raffrayanus, is characterised by the length of the rostellar hooks, the shape of the ovary, the arrangement of the testes in a triangle and the extent of the cirrus-sac. Hymenolepis aklei, H. bradleyi, H. antechini, H. bettongiae, H. cercarteti, H. isoodontis and H. potoroi are transferred to Vampirolepis as new combinations. E. kalubu is a new host for Linstowia semoni and Pogonomelomys ruemmleri is a new host for Hymenolepis diminuta. V. peroryctis is the first platyhelminth to be reported from Peroryctes raffrayanus and Raillietina (Raillietina) sp. the second to be reported from the genus Melomys.  相似文献   

7.
Three new species of the sciaenid genusAtrobucca are described:A. kyushini from off Borneo, differs from all known congeners in having no swimbladder appendages enveloplng the bladder, no forward directed branches from the ventral limbs of the appendages, a long tube-like last appendage parallel to the bladder wall and a pale mouth lining;A. brevis from off northern Australia and Papua New Guinea, is distinguished by its short pectoral fin (less than 23% SL) and pleural rib on the 11th vertebra;A. adusta from Papua New Guinea, is distinctive in having a low dorsal soft ray number (23–24) and long caudal peduncle (27–30% SL).Atrobucca Chu, Lo et Wu is redefined to accommodate the new species: the genus is principally characterized by the swimbladder appendages divided into developed dorsal and ventral limbs, and the only slightly curved sulcus tail of the sagitta. A key and diagnoses are provided for all known species ofAtrobucca.  相似文献   

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The estuary of the Limmen Bight River in Australia's Northern Territory is home to an unusual salt water-adapted population of the Australian `freshwater' crocodile, Crocodylus johnstoni. Crocodiles were captured from tidal reaches of the estuary ranging in salinity from 0.5–24‰ and from several permanent fresh water reaches more or less remote from saline waters. C. johnstoni is an effective osmoregulator in moderately saline waters and has osmoregulatory mechanisms very similar to its more marine-adapted relative, the estuarine crocodile Crocodylus porosus. Fasted C. johnstoni in brackish water appear to lose little sodium in cloacal urine, relying on their lingual salt glands for excretion of excess sodium chloride. The lingual glands show clear evidence of short-term and long-term acclimation to salt water. Like estuarine crocodiles, C. johnstoni drinks fresh water and will not drink sea water. Gross sodium and water fluxes in brackish water are very similar to those in other crocodilians, suggesting differences in integumental permeability are not a major influence on osmoregulatory differences between crocodilians. The data reinforce the hypothesis that crocodylids differ fundamentally from alligatorids in the structure and function of the renal-cloacal-salt gland complex and are of interest in current debate over the evolutionary and zoogeographical history of the eusuchian crocodilians. Accepted: 25 February 1999  相似文献   

10.
Rhodocybe pulchrisperma is described as a new species of Agaricales from North America. It belongs in section Rhodocybe due to the brightly colored pseudocystidia and lack of clamp connections. The very large, handsomely ornamented basidiospores distinguish this species from others in the section. A key to taxa from Florida, Papua New Guinea, and India that exhibit similar features is presented.  相似文献   

11.
Ömer Çelebi  Elif Sevim  Ali Sevim 《Biologia》2014,69(10):1365-1375
Eurygaster integriceps (Hemiptera: Scutelleridae) is one of the most serious pest of wheat and other cereal crops throughout the Near and Middle East including Turkey. To contribute biological control of this pest, we investigated the culturable bacterial flora of E. integriceps and their virulence against it. We also tested different entomopathogenic fungi (Isaria fumosorosea ARSEF8356, Beauveria bassiana ARSEF8356, Metarhizium brunneum ARSEF8671 and Nomurae rileyi ARSEF1670) against this pest under laboratory conditions. Bacterial isolates were characterized based on morphological, biochemical, physiological and molecular characteristics (16S rRNA sequencing). The isolates were identified as Pantoea sp. (S1, S5, S7, S8, S10 and S11), P. agglomerans (S2, S3 and S4), Pseudomonas sp. S6 and Micrococcus luteus S9. The highest mortality within bacterial isolates was observed from Pantoea sp. S1, P. agglomerans S4 and Pantoea sp. S7 with 100%. Mortality of other bacterial species ranged from 33% to 88%. The highest mortality among the tested entomopathogenic fungi was obtained from Isaria fumosorosea ARSEF 8333 with 100%. Mortality of other fungi ranged from 33% to 50%. Consequently, Pantoea sp. S1, P. agglomerans S4, Pantoea sp. S7, Beauveria bassiana ARSEF 8356 and Isaria fumosorosea ARSEF 8356 seem to be promising candidates in the control of E. integriceps.  相似文献   

12.
The Gidra-speaking Papuans of the Oriomo Plateau, lowland Papua New Guinea, consume ash of two tree species (Melaleuca sp. andAcacia mangium) as a native salt. The ashes contain 100–200 mg sodium/g ash, which is very much higher than the sodium levels in native plant ashes (except for the swamp herbEriocaulon australe) collected in other regions of the world.  相似文献   

13.
Analyses of nearly 3000 hr of hunting for mammals by Etolo people of Papua New Guinea reveal that older hunters were more successful than younger hunters, that increased success was due, in large part, to higher rates of capture for only two of 24 prey species, and that access to a good hunting dog accounted for the increase in rate of capture for one of these two species. A comparison of Gadio Enga and Rofaifo mammal hunting with that of Etolo reveals a marked decline in energy and protein yields with increase of altitude. This is attributed to altitudinal changes in the composition of the available fauna within Papua New Guinea and to reinforcing effects from increased human population density.  相似文献   

14.
Three species of lepidopterous larvae were collected fromAmaranthus hybridus L. growing in field corn during 1975 and 1976 at Hastings, Florida.Spodoptera exigua (Hubner) was the predominant species in May.Spodoptera eridania (Cramer) was predominant in June andHerpetogramma bipunctalis (F.) in July and August. Nine native species of parasites, representing theBraconidae, Eulophidae, Ichneumonidae andTachinidae, emerged from these larvae.Meteorus autographae Muesebeck emerged from bothS. exigua andS. eridania. TheTachinidae, Winthemia rufopicta (Bigot),Eucelatori rubentis (Coquillett) andLespensia sp., emerged from mixtures ofS. exigua andS. eridania. Apanteles marginiventris (Cresson),Temelucha sp., andChelonus texanus Cresson emerged from bothS. exigua andH. bipunctalis larvae, andEuplectrus platyhypenae Howard andOphion sp. emerged fromS. eridania. All the species of parasites from the lepidopterous larvae that feed onAmaranthus hybridus are also reported as parasites ofS. frugiperda, a serious pest of corn. Therefore these larvae onA. hybridus may be a source of the parasites found attackingS. frugiperda.  相似文献   

15.
Pandanus is well represented in Papua New Guinea with over 66 species growing from sea level to 3,000 m. The territory of the Wopkaimin, who live at the headwaters of the Ok Tedi in the Star and Hindenburg Mountains, is particularly rich in wild and domesticated species ofPandanus. Detailed analysis of the species in classification, ecology, subsistence, ritual and material culture not only establishesPandanus as a locally significant plant resource but also contributes to the comparative understanding of ethnobiological systems. A close correspondence with botanical taxa of generic and specific rank and an absence of the most inclusive taxon term for plant are 2 cross-culturally important findings substantiated in WopkaiminPandanus taxonomy.  相似文献   

16.

Background

Crocodilians (Order Crocodylia) are an ancient vertebrate group of tremendous ecological, social, and evolutionary importance. They are the only extant reptilian members of Archosauria, a monophyletic group that also includes birds, dinosaurs, and pterosaurs. Consequently, crocodilian genomes represent a gateway through which the molecular evolution of avian lineages can be explored. To facilitate comparative genomics within Crocodylia and between crocodilians and other archosaurs, we have constructed a bacterial artificial chromosome (BAC) library for the Australian saltwater crocodile, Crocodylus porosus. This is the first BAC library for a crocodile and only the second BAC resource for a crocodilian.

Results

The C. porosus BAC library consists of 101,760 individually archived clones stored in 384-well microtiter plates. Not I digestion of random clones indicates an average insert size of 102 kb. Based on a genome size estimate of 2778 Mb, the library affords 3.7 fold (3.7×) coverage of the C. porosus genome. To investigate the utility of the library in studying sequence distribution, probes derived from CR1a and CR1b, two crocodilian CR1-like retrotransposon subfamilies, were hybridized to C. porosus macroarrays. The results indicate that there are a minimum of 20,000 CR1a/b elements in C. porosus and that their distribution throughout the genome is decidedly non-random. To demonstrate the utility of the library in gene isolation, we probed the C. porosus macroarrays with an overgo designed from a C-mos (oocyte maturation factor) partial cDNA. A BAC containing C-mos was identified and the C-mos locus was sequenced. Nucleotide and amino acid sequence alignment of the C. porosus C-mos coding sequence with avian and reptilian C-mos orthologs reveals greater sequence similarity between C. porosus and birds (specifically chicken and zebra finch) than between C. porosus and squamates (green anole).

Conclusion

We have demonstrated the utility of the Crocodylus porosus BAC library as a tool in genomics research. The BAC library should expedite complete genome sequencing of C. porosus and facilitate detailed analysis of genome evolution within Crocodylia and between crocodilians and diverse amniote lineages including birds, mammals, and other non-avian reptiles.
  相似文献   

17.
We examined agonistic behaviour in seven species of hatchling and juvenile crocodilians held in small groups (N = 4) under similar laboratory conditions. Agonistic interactions occurred in all seven species, typically involved two individuals, were short in duration (5–15 seconds), and occurred between 1600–2200 h in open water. The nature and extent of agonistic interactions, the behaviours displayed, and the level of conspecific tolerance varied among species. Discrete postures, non-contact and contact movements are described. Three of these were species-specific: push downs by C. johnstoni; inflated tail sweeping by C. novaeguineae; and, side head striking combined with tail wagging by C. porosus. The two long-snouted species (C. johnstoni and G. gangeticus) avoided contact involving the head and often raised the head up out of the way during agonistic interactions. Several behaviours not associated with aggression are also described, including snout rubbing, raising the head up high while at rest, and the use of vocalizations. The two most aggressive species (C. porosus, C. novaeguineae) appeared to form dominance hierarchies, whereas the less aggressive species did not. Interspecific differences in agonistic behaviour may reflect evolutionary divergence associated with morphology, ecology, general life history and responses to interspecific conflict in areas where multiple species have co-existed. Understanding species-specific traits in agonistic behaviour and social tolerance has implications for the controlled raising of different species of hatchlings for conservation, management or production purposes.  相似文献   

18.
Two new genera of Chrysobalanaceae are described.Hunga distributed in New Caledonia, the Loyalty Islands and Papua and New Guinea, contains eight species, three new, and five formerly placed in the generaAngelesia, Licania andParinari.Kostermanthus is described to accommodate two species with united filaments formerly placed inParinari andAcioa. Both new genera are quite as distinct as others of the family and have been overlooked by undue emphasis placed on the single character of a bilocular ovary.Licania palawanensis Prance is also described; it is the second species of its genus from Malesia.  相似文献   

19.
Scavenging is an important component to the overall ecology of consumers in virtually all ecosystems on Earth. Given the energetic benefits of foraging on these resource subsidies, opportunistic predators will adjust their behaviors accordingly to maximize access. One of the many consequences of large-scale scavenging opportunities is species interactions that are rarely observed in nature. Here we describe the first published record of predatory sharks (tiger sharks, Galeocerdo cuvier) and saltwater crocodiles (Crocodylus porosus) foraging together in space and time, as documented on a large whale carcass off Western Australia. We report on and discuss the behaviors of the sharks and crocodiles in the hope of shedding new light on the interactions between apex predators that are rarely seen together, but may overlap under specific contexts.  相似文献   

20.
A new species of tongue sole,Paraplagusia longirostris, is described from 59 specimens (83.0– 276.2 mm SL) collected off the northern coast of Australia and southern coast of Papua New Guinea.P. longirostris is easily distinguishable from otherParaplagusia by its long, obtusely pointed snout and its high counts for dorsal and anal fin rays, caudal vertebrae and mid-lateral line scales.  相似文献   

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