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1.
Abstract

Albumin evolution is examined within the anuran genus Leiopelma using the quantitative immunological technique of micro-complement fixation (MC'F). The albumins of L. archeyi and L. hamiltoni are relatively similar to each other, yet both differ greatly from the albumin of L. hochstetteri. Using albumin as a molecular clock, we estimate that L. hochstetteri diverged from the lineage leading to L. archeyi and L. hamiltoni during the Miocene, about 15 million years ago. The divergence of L. archeyi and L. hamiltoni appears to have been a Pliocene event (about 3 million years ago).  相似文献   

2.
Allozyme variation was studied the three living species of Leiopelma. L. hamiltoni and L. archeyi are shown to be closely related to each other although L. hamiltoni is slightly more divergent relative to L. hochstetteri. This parallels previous cytoenetic data. The rarity and insularity of L. hamiltoni enables the calculation of a mutation rate based on genetic variance and population size. A mutation rate per generation of 2.7times 10--6 is sufficient to account for the observed levels of variation. Six populations of L. hochstetteri show a pattern of genetic divergence that also closely parallels previously detected cytogenetic variation. L. hochstetteri is genetically distant from its congeneric species while all species of Leiopelma are at an extreme genetic distance from Ascaphus truei, the only other living amphicoelous fro At the limits of resolution of the allozme technique, Ascaphus clusters with the more morphologically advanced frogs, Discogiossus and Bombina, rather than with Leiopelma. Taken with other evidence, this supports recognition of two families, Leiopelmatidae anl Ascaphidae, with Leiopelma the probable sister group of all other frogs.  相似文献   

3.
Abstract

A reappraisal of the conservation status of the New Zealand frog fauna is presented using the 2008 version of the New Zealand Threat Classification System. Of New Zealand's four extant endemic species, three are judged to be ‘Threatened’ (Leiopelma hamiltoni being ‘Nationally Critical’, and L. pakeka and L. archeyi being ‘Nationally Vulnerable’) and one ‘At Risk’ (L. hochstetteri ‘Declining’). Three Leiopelma species are listed as extinct—they are known from bone deposits in caves throughout the country until some time in the last 1000 years. Three introduced and naturalised Litoria species are abundant in New Zealand although two (L. aurea and L. raniformis) are threatened in their country of origin (Australia). An additional unidentified frog taxon from northern Great Barrier Island is listed as ‘Data Deficient’.  相似文献   

4.
Abstract

A terrestrial endemic frog resembling Leiopelma archeyi was discovered in the Whareorino Forest, northern King Country, New Zealand, in 1991, where it is broadly sympatric with L. hochstetteri. To clarify its taxonomic status, allozyme electrophoresis of toe tissue was used to compare it genetically with four other populations of terrestrial Leiopelma (L. archeyi from Tapu and Tokatea, Coromandel; L. hamiltoni from Stephens Island; L. pakeka from Maud Island). Thirteen presumed genetic (allozyme) loci could be consistently scored for the five populations. At 11 loci, no genetic differences were found between the Whareorino frog and the two Coromandel L. archeyi populations. Allelic frequencies differed slightly at two loci. We therefore conclude that the terrestrial Whareorino frog represents a western population of L. archeyi. L. hamiltoni from Stephens Island is genetically closer to L. archeyi than is L. pakeka from Maud Island. The Whareorino L. archeyi population is morphologically similar to Coromandel L. archeyi populations, although multivariate analysis suggests subtle morphological differences, including the relative position of the nostril. Size comparisons between Whareorino and three Coromandel sites (Moehau, Tapu, Tokatea) show there were more larger frogs (35–38 mm snout‐vent length) at Whareorino and Tokatea compared with Moehau and Tapu, where maximum snout‐vent lengths were 34 and 36 mm, respectively.  相似文献   

5.
Endemic New Zealand frogs of the genus Leiopelma are from a basal lineage of extant anurans that release defensive secretions onto their skin when disturbed. Here, we characterize the gross anatomy and microscopic structure of the skin of L. archeyi, L. hochstetteri, and L. pakeka using stereoscopic, light and transmission electron microscopy. The terrestrial L. archeyi and L. pakeka possess dimorphic granular glands, categorized as type I and II, based on their frequency and morphological traits, whereas the semi‐aquatic L. hochstetteri lacks type I glands. This is the first report of differential dimorphism in anurans of the same genus. This dimorphism could be interpreted as an adaptation to different physiological or ecological needs of these species. However, species within this ancient genus share similar general gland morphology with other anurans, namely, a secretory unit containing storage granules ensheathed by myoepithelial cells. Type I glands are ellipsoid, large and contain a homogeneous mass of electron‐dense granules (1.8 ± 0.08 μm in diameter). Type II glands are round and contain larger heterogeneous granules (4.06 ± 0.16 μm) of varying densities. Exposure to noradrenaline causes the contraction of myoepithelial cells, resulting in bulk discharge of type I glands through the epidermal duct onto the skin surface. Differential release of secretions from dimorphic glands may be indicative of their functional specialisation in antipredatory or regulative roles. Mass spectrometric techniques were used to de novo sequence peptides present in the skin secretions of Leiopelma species. A total of 30 previously undescribed peptides from Leiopelma species were fully or partially sequenced. These peptides exhibited no similarity to any known compounds. J. Morphol. 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

6.
Abstract

A new population of terrestrial Leiopel‐matid frog was discovered in the Whareorino Forest, northern King Country, New Zealand, in 1991. Searches were carried out from June 1991 to December 1993 to determine the species present and to document variation in external morphology, habitat, and local distribution. These confirmed that a terrestrial frog resembling L. archeyi is present in the area, as well as Hochstetter's frog Leiopelma hochstetteri and the introduced Australian hylid frog Litoria aurea.

In Whareorino Forest, the terrestrial Leiopelma was mostly above 500 m altitude and L. hochstetteri above 350 m. The terrestrial Leiopelma occupies sites under rocks and logs in forest. It also occurs in vegetation, such as crown fern Blechnum discolor, tree fern Cyathea smithii, hook grass Uncinia uncinata, and rice grass Microlaena avenacea. Egg clusters of this frog were found in crown fern and tree fern, as well as under stones.

The terrestrial Leiopelma is susceptible to predation by Litoria aurea and rats. This is the first documented evidence of predation on Leiopelma on the New Zealand mainland. The future of this small remnant Leiopelma population is uncertain, and further investigation of the impact of anuran and mammalian predators is needed.  相似文献   

7.
Abstract

Leiopelma hochstetteri, the most widespread of New Zealand's native frogs, is recognised as threatened, and is fully protected by legislation. As a first step to characterise the diet and trophic level of L. hochstetteri within streams in the Waitakere Ranges, Auckland, stable carbon and nitrogen isotope analyses were undertaken on a variety of sympatric terrestrial and aquatic plant and animal species, including adult frogs. These results show that: (1) aquatic and terrestrial food webs are linked by terrestrial inputs into the stream; (2) invertebrate and vertebrate predators separate well into distinct trophic groups, and (3) L. hochstetteri occupies an intermediate trophic position among predators, with a diet, at least as an adult, comprising terrestrial invertebrates. Shortfin eels and banded kokopu are identified as potential predators of L. hochstetteri, but data for rats are inconclusive. These results have important implications for the conservation of New Zealand native frog species and riparian stream habitat.  相似文献   

8.
List of Members     
Abstract

Bazzania okaritana, a new species from South Island, New Zealand, is described and illustrated, and a comparison with similar species is made. The new species is most similar to Bazzania hochstetteri (Reichardt) E.A. Hodgs. and Bazzania exempta J.J. Engel, but differs in several respects from both these species.  相似文献   

9.
Leiopelma hochstetteri belongs to a singular anuran lineage endemic to New Zealand that diverged from other frogs about 200 million years ago. The species now is reduced to a series of isolated populations in the northern half of the North Island and Great Barrier Island. We have used mitochondrial and nuclear sequence data to examine the genetic affinities of extant populations of L. hochstetteri. Phylogenetic reconstructions reveal that populations are highly structured. Each of the geographically isolated populations harbours independent mtDNA lineages as well as different degrees of nuDNA differentiation. Moreover, molecular dating reveals that this structure originated in the early Pleistocene. This pattern of genetic structure likely results from unfavourable climatic conditions during the Pleistocene combined with the low dispersal ability of the species. Isolated populations in forested refugia existed even in the southern part of the distribution of the species during glacial cycles. Previously published variation in chromosome numbers and isozyme data are consistent with the new evidence. We identified 13 evolutionary significant units (ESUs) that should serve as the focus for future management and conservation of this species.  相似文献   

10.
Abstract

An alternative classification of the New Zealand rhytidid genus Powelliphanta O'Connor, 1945 is presented. P. gilliesi (Smith, 1880) and P. hochstetteri (Pfeiffer, 1862) are recognised as species, and the following subspecies are recognised within hochstetteri: h. superba (Powell, 1930); h. lignaria (Hutton, 1880); h. rossiana (Powell, 1930); h. fiordlandica (Climo, 1971). A model is explained which suggests that all described species and subspecies of Powelliphanta are part of a complex ring species. This developed as a result of glacial disjunction of South Island populations and hybridisation across a Cook Strait land bridge formed during the last Pleistocene glaciation.  相似文献   

11.
《Journal of bryology》2013,35(2):101-103
Abstract

Photosynthetic responses to light intensity were studied under laboratory conditions in seven bryophyte species from evergreen laurel forest, a threatened habitat, on Terceira island in the Azores. Four mosses (Andoa berthelotiana, Echinodium prolixum, Fissidens serrulatus, Myurium hochstetteri) and three liverworts (Bazzania azorica, Frullania tamarisci, Lepidozia cupressina) were selected to encompass a range of potential responses to variations in the forest light environment. Carbon dioxide exchange measurements were made, using an infra-red gas-analyser, at photosynthetic photon flux densities (PPFD) of 0-900 µmol m-2 s-1 and a mean temperature of 21°C in fully hydrated shoots. Most species achieved light saturation of photosynthesis below 30 µmol m-2 s-1, the lowest value being for A. berthelotiana (20 µmol m-2 s-1) and the highest for M. hochstetteri (68 µmol m-2 s-1). The liverwort F. tamarisci had the highest maximum photosynthetic rate (Pmax, 23 µmol CO2 g-1 h-1) whereas Pmax was lowest in the mosses E. prolixum and M. hochstetteri (10 µmol CO2 g-1 h-1). Dark respiration rate, a critical factor in toleration of shade by forest floor plants, was highest in the species with the highest values for Pmax. Compensation point was extremely low (7 µmol photons m-2 s-1) in Fissidens serrulatus, a species found in the deep shade of forest ravines and caves, and highest in M. hochstetteri a moss restricted to better illuminated habitats within and outside the forest. No photoinhibition was detected during the relatively short exposures to high irradiances. Comparison of these responses with data on the forest light environment indicates that, despite the possession of considerable shade adaptations, during winter in the evergreen laurel forest, low light levels may often limit photosynthetic rates of the bryophytes.  相似文献   

12.
Analysis of morphological and phenological data for determining the genetic variation within sevenLolium species led to the recognition of two groups within this genus. One group, containing the two inbreeding speciesL. temulentum andL. persicum, was clearly distinct from all other species. Strong morphological and phenological intergradation was found between both species. The cross-breeding species,L. perenne, L. rigidum, andL. multiflorum, formed another group. Little differentiation was found between these species, though they were distinct. Two inbreeding species,L. loliaceum andL. remotum, were clearly distinct from each other and the two groups.L. loliaceum had an isolated position and was most related toL. rigidum. L. remotum had an intermediate position between the cross-breeding and inbreeding species, and was almost equally distant from all three cross-breeding species.Genetic variation inLolium spp. I.  相似文献   

13.
The species Proconsul (Xenopithecus) hamiltoni was based on two weathered molars in a maxillary fragment from the Erageleit beds, Lothidok, Turkana District, Kenya. New fossils from Lothidok show a unique suite of features indicating generic distinction of this taxon from other known large early catarrhines. A new generic diagnosis is given. The new genus, although still poorly known, may be the first Oligocene hominoid from East Africa. It retains many primitive features, but the few derived ones hint that it may be related to the Afropithecus group.  相似文献   

14.
Six New Zealand species are treated. 1. The correct basionym reference forBazzania hochstetteri (Reichardt) Hodgson is Reichardt (1866). A key to the New Zealand vittate species ofBazzania is included. 2. The correct citation forBazzania mittenii (Stephani) Stephani is given. 3.Lepidozia leptodictyon Herzog is placed in the synonymy ofPseudocephalozia lepidozioides R. Schuster. 4.Metahygrobiella chilensis Engel & Schuster is a new name forCephalozia heteroica Schuster & Engel. 5.Metzgeria alpina Schuster & Engel is described as new. 6. The correct citation forPachyglossa Herzog is Herzog (1952).  相似文献   

15.
Different species of the bristletail genus Lepismachilis were collected in 14 localities in Italy and Spain and an allozyme electrophoretic survey was carried out to estimate the degree of genetic variability and differentiation at intra- and interspecific levels. Four morphological species were initially identified (L osellai, L. y-signata, L. affinis, L. targionii), but the electrophoretic analysis demonstrated the presence of two additional species among the individuals of L. targionii (Lepismachilis spl and sp2). The validity of these species and their differentiation from L targionii were demonstrated by the fixation of alternative allelic patterns at several loci (7 in Lepismachilis spl and 8 in Lepismachilis sp2), coupled with fixed, previously undetected, morphological differences. In addition, Lepismachilis sp2 was sympatric with L. targionii in three collecting sites, where the fixation of alternative allelic patterns unequivocally demonstrated reproductive isolation. Genetic variability did not seem to be correlated with local ecological factors, and differences between species should rather be explained by different historical factors. Low levels of gene flow, estimated with two different indirect methods, were observed in L. targionii and L. y-signata, and were due to high levels of structuring among populations. Genetic differentiation among conspecific populations was not correlated to their geographical arrangement and the presence of loci fixed for different alleles among them suggested that stochastic factors (such as genetic drift) may have played a role in determining genetic differentiation of geographically isolated populations. Genetic divergence values indicated that the six species are well differentiated and allozyme profiles were diagnostic for all of them. On the other hand, allozyme data did not provide adequate information to resolve evolutionary relationships among the species, nor did they confirm the validity of the two subgenera (Lepismachilis and Berlesilis) in which the genus Lepismachilis is traditionally divided.  相似文献   

16.
17.
Electrophoretic surveys of 13 enzyme-coding loci distinguished unambiguously five morphologically defined species of Porites and two species of Goniopora. Each species was identifiable solely by unique, qualitative banding patterns at 1–6 loci. Genetic distances give preliminary estimates that these Porites species diverged from common ancestors 8–22 Ma during the Miocene, and that the two Goniopora species diverged about 3.5 Ma in the Pliocene, assuming Porites evolved from Goniopora 55 million years ago (Ma). Correspondence to: R. L. Garthwaite  相似文献   

18.
Characters used un specific identification of Zoraptera are briefly discussed. A list of Neotropical species is given, and the difficulties of associating sexes of some species outlined. Two new species are described and figured (Zorotypus weidneri sp.n., ♂, ♀, Brazil; Z.hamiltoni sp.n., ♂, ♀, Colombia) and additional records and information given on Z.shannoni Gurney (♂, Brazil) and Z.huxleyi Bolivar y Pieltain & Coronado G (♂, ♀, recorded from Brazil for the first time).  相似文献   

19.

Plesiochorus Looss, 1901 is a genus of Gorgoderidae infecting the urinary bladders of marine turtles globally. Currently, just two morphologically similar species are recognised, Plesiochorus cymbiformis (Rudolphi, 1819) Looss, 1901 and Plesiochorus elongatus Pigulevsky, 1953, which have been distinguished by molecular data and subtle morphological differences. Here we describe a new species, Plesiochorus irwinorum n. sp., infecting hawksbill turtles (Eretmochelys imbricata (L.)), which is primarily distinguished from the other two species of Plesiochorus on the basis of ITS2, cox1 and 28S sequence data. Morphometric data for specimens examined during this study overlap between P. cymbiformis and P. irwinorum n. sp. for every measured feature, rendering them functionally cryptic. However, principal components analysis clearly distinguishes the two species. Additionally, we report new specimens of P. cymbiformis, and provide new sequence data for specimens from Australian loggerhead (Caretta caretta (L.)) and hawksbill turtles. There is little understanding of the host-specificity or geographical distribution of the three species of Plesiochorus, and it remains possible that some of the previously reported sequences have been attributed to the wrong species.

  相似文献   

20.
The presented contribution concerns the study of several samples of Microcoryphia and of Zygentoma obtained in Israel; an up to date of the species of these insect Orders reported from Palestine is also presented. Genus Hyperlepisma (Lepismatidae: Ctenolepismatinae) is reported for the first time from the country and one new species H. palaestinensis n. sp., is described from the northern Negev. Another new species this one of the genus Lepidospora s. s. (Nicoletiidae: Coletiniinae), L. (L.) ayyalonica n. sp., is described from the Ayyalon Cave in Western Central Israel, from where several other terrestrial and aquatic endemic arthropods were already known.  相似文献   

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