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1.
Abstract

Morphological and behavioural comparison of Neothyris lentleularis lenticularis with other extant members of its genus shows that N. lentieularis eompressa should be elevated to species rank. Recent species of Neothyris all ottur as free-lying populatrons, and the characters which differentiate N. lenticularis and N. compressa are associated with different methods of orientation. Inferences drawn from the morphology of N. dawsoni indicate that the need for orientation may not exist in the environments it occupies.  相似文献   

2.
Abstract

The gonads of Notosaria nigricans, Terebratella inconspicua, T. ronguinea, Liothyrella neozelanica. and Neothyris ienticuiaris from southern New Zealand are described and their breeding state is determined. Attempts to induce spawning were not successful even with individuals that appdatred ripe. Sinlce normal fertilisation did not take place even with stripped gametes, it is concluded that either the brachiopods examined were not fully ripe or some indeterminate factor was inhibiting normal development of the zygotes.  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

The sequence and timing of events in the emergence of Uropetala carovei carovei (White) are described. Contrary to published opinion, emergence is shown to be of the ‘upright type’ seen also in the petalurids Tanypteryx pryeri (Selys) and Tachopteryx thoneyi (Hagen). The accuracy of accounts of ‘hanging type’ emergence behaviour in Petalura gigantea Leach and Tanypteryx hageni (Selys) is questioned.  相似文献   

5.

Two strophomenid brachiopod shell pavements bearing abundant edrioasteroid epizoans occur stratigraphically within the top 4.5 m of the Corryville Formation (Upper Ordovician, Maysvillian) in Boone County, Kentucky, and Hamilton County, Ohio. Both assemblages are dominated by Isorophus cincinnatiensis and contain Carneyella pilea and Streptaster vorticellatus as lesser constituents. Pedicle exterior valves of Rafinesquina “alternata”; are the preferred substratum for all species at both sites, but the Kentucky population occurs mainly on unabraded, articulated shells and the Ohio population occupies abraded, disarticulated shells. The Kentucky population includes a greater size range of Isorophus (at least three cohorts) than the Ohio population (at least two cohorts), suggesting a greater time span of colonization for the Kentucky site. Host shells from Kentucky have anterior‐posterior axes strongly aligned NE‐SW whereas the Ohio shells are unoriented. Isorophus in Kentucky show a preference for the anterior margin of the Rafinesquina pedicle exterior valve, whereas Isorophus in Ohio show no preferred location on host shells. The Kentucky edrioasteroids are inferred to have attached to mainly live Rafinesquina in brachial‐valve‐up position. Host shells were inverted and oriented by a NE‐SW storm surge, then buried rapidly. Ohio edrioasteroids occupied mainly dead, already inverted host shells not oriented by storm surge possibly because of their more downslope (distal) location. Comparative taphonomic relationships between the two coeval populations are consistent with a model of proximal to distal distribution along a gentle shallow subtidal N‐S paleoslope subject to episodic storm activity.  相似文献   

6.
Abstract

Terebratella sanguinea and T. incollSpicua have been differentiabed on foramen position and ornament. Further comparison shows that the valves of T. sanguinea are more strongly curved than those of T. inconspicua, a condition resulting in a longer pedicile, a larger beak, and hinge plates with greater elevation. The relationship between hinge plate ccndition and shell curvature is evident in other terebratellid genera.  相似文献   

7.
Chromatographic and spectrophotometric methods were used to identify the floral anthocyanins of Broughtonia domingensis, B. negrilensis, B. sanguinea, Brassotonia ‘John Miller,’ Diabroughtonia, Brassavola nodosa, Cattleyopsis lindenii, and Cattleytonia ‘Rosy Jewell’ for the purpose of establishing chemotaxonomic relationships and inheritance patterns. Flowers of Brassavola nodosa were found to contain raphanusin C, an anthocyanin not present in Cattleyopsis lindenii or in any of the Broughtonia species and hybrids. Pelanin is present in flowers of Broughtonia domingensis and B. negrilensis, but not in those of B. sanguinea. Raphanusin B, raphanusin D, and pelargonidin-3-glucoside, 5-sophoroside which are present in B. sanguinea were also found in its intergeneric hybrids with Diacrium and Brassavola. These findings suggest that Cattleyopsis lindenii should not be transferred to Broughtonia and that B. domingensis, B. negrilensis, and B. sanguinea are separate species.  相似文献   

8.
Abstract

Ibla idiotica, Lepas australis, Calantica villosa, Chamaesipho columna, Tetraclitella purpurascens, Notobalanus vestitus, and Notomegabalanus campbelli are reported for the first time from The Snares. The occurrence of Calantica spinosa and Epopella plicata is confirmed. Habitat information and recorded distribution in New Zealand are given for each species. The Snares barnacle fauna is restricted both in diversity and in numbers of individuals. This may be due to high wave energies, strong winds which aid desiccation, and counter-flow of currents, which might disrupt larval dispersal from the north and north-west.  相似文献   

9.
The feeding of five terrestrial planarians found in New Zealand on European lumbricid earthworms was studied. Under laboratory conditions between 60–83% of Artioposthia spp. fed in the first 24 h compared with 21–40% of Australoplana spp. The mean percentage weight gain varied from 31% for Australoplana sanguinea var. alba to 113% for Artioposthia sp. 1. Analysis of the weights of the planarian species showed a mean 11-fold difference between Australoplana sanguinea and Artioposthia triangulata and that these body weights were not related to mean percentage weight gains after feeding. The relationship between the weights of egg capsules and pregnant female planarians was similar for Australoplana sanguinea var. alba (11%), Artioposthia triangulata (12%) and Artioposthia testacea (13%). This study confirms that there are terrestrial planarians in New Zealand which have the potential to prey upon European lumbricid earthworms but which have not been detected in Europe. Greater knowledge of their biology is necessary to control the spread and impact of these organisms around the world.  相似文献   

10.
Morphometric data and general observations of habitat conditions, feeding behaviour and reproductive biology are presented for the land planarian Australoplana sanguinea var. alba, based upon a population established at a garden centre in Alexandra, South Island, New Zealand. The flatworm species considered in this study appears to be identical to an alien flatworm initially referred to as Geoplana sanguinea (Moseley) var. alba (Dendy) which has successfully colonised areas of the British Isles over the past few decades. The study also highlights the importance of garden centres and nurseries as modified habitats that provide favourable conditions for terrestrial planarians, implying that exotic flatworm species have the potential to spread and exist in pockets world-wide.  相似文献   

11.
I present a simulation model on vital statistics, absolute abundance (N, total number of individuals that ever lived) and preservation rate (p, minimum number of fossils known divided by N) of Tyrannosaurus rex. It is based on a published age-structured population model that assumes a reptile or bird-like reproduction for T. rex to estimate its age-specific survival rates. My model applies input variables and equations from a recently published model on N and p. This model yielded 2.5 billion T. rex individuals (N) and one fossil per 80 million individuals (p). The average N values calculated by my model were at minimum 27.6% and p values at maximum 361.5% that of a previous model and uncertainties in all output variables were always larger in my model. The equation on output variable ‘population density’ introduced the largest uncertainty to N and p. The output variable ‘generation time’ differed the most between models, but for N and p, the huge size of the input area modelled and geological longevity minimized this difference. Unlike my model, the generation time as well as life expectancies, gross reproduction rates, and reproductive values of individuals calculated from the previous model all strongly contradicted our current understanding of the biology of T. rex and of other theropods. Their values also disagreed with those of large extant reptiles, birds and mammals. All of these shortcomings of the previous model favour the assessment of individual and population characteristics of T. rex and of other extinct species using my model.  相似文献   

12.
Phylogenetic reconstructions using parsimony, maximum likelihood (ML), and Bayesian relaxed molecular clock analyses of ~2850 nucleotides of nuclear‐encoded small and large subunit ribosomal DNAs (SSU and LSU rDNAs) from 14 long‐looped (terebratelloid) ingroup and four short‐looped (terebratulidine) outgroup brachiopod taxa, together with ML analyses of ~663 nucleotides of mitochondrial cytochrome oxidase subunit 1 (cox1) from 12 terebratelloid taxa, show that deep divergence separates taxa endemic to waters in the vicinity of New Zealand from those with a Magellanic distribution around South America and Antarctica. This deep divergence also separates Magellanic Terebratella dorsata from New Zealand Terebratella sanguinea, showing that they are not congeneric. Instead, they belong to separate ‘Magellanic’ (MAG) and ‘New Zealand’ (NZ) clades that first diverged about 82 Mya (95% highest posterior density, 48–120 Mya), correlating with separation between the NZ and Antarctic tectonic plates. Sequence analyses also reveal (1) that the Antarctic endemic taxa Magellania fragilis and Magellania joubini are not congeneric with Magellania venosa, suggesting that their previous placement in Aerothyris should be restored, and (2) that divergence between Antarctic and NZ species of the terebratulide Liothyrella occurred much later than plate separation, perhaps because of continuing gene flow caused by long‐lived larvae. The topology of the rDNA and cox1 gene trees implies that radial ornament of the shell (‘ribbing’) has been gained (and/or lost) independently within the MAG and NZ clades. Radial ribs are widespread in articulate brachiopods throughout the Phanerozoic, but no comparisons of brachiopod rib morphology and morphogenesis have been published. Our comparisons of transverse shell mid‐sections in the scanning electron microscope reveal no obvious evidence of differences in morphology between independently gained ribs. We also consider several ways in which ribs may affect fitness, including effects on hydrodynamics. Only scanty and inconclusive evidence is available, but we suggest that effects (if any) are likely to be of small magnitude; adaptive value of brachiopod shell ribs remains to be demonstrated. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 631–645.  相似文献   

13.
Abstract. Age-states, population structure, and seedling regeneration of the grass Chionochloa pallens were investigated in eight alpine grassland stands representing the range of canopy cover (ca. 5–75 %) and basal area (112 - 3889 m2/ha-1) in the headwaters of the Avoca catchment, Canterbury, New Zealand. In open-canopy stands (< 50 % canopy cover, < 2000 m2/ha-1 basal area) C. pallens individuals were clearly distinguishable. Rela-tionshipsbetweenbasal diameter, number of tillers, height, and % crown death suggested four putative age-states: ‘seedlings‘, ‘juvenile tussocks’, ‘mature tussocks’ and ‘senescent tussocks’. Four types of population structure were identified depending onthe proportions of seedlings and juvenile and mature tussocks. C. pallens seedlings were present in seven stands at densities ranging from 0.6 to 123.4 / m2. They were most frequent on microsites protected from frost-heave by short herbaceous vegetation or litter, but with little competition from taller vegetation. Differences in seedling densities between stands partly reflected the proximity and abundance of seed sources and degree of protection from frost-heave. C. pallens population structures appear to be influenced by the frequency and magnitude of geomorphic disturbances and browsing by introduced animals.  相似文献   

14.
Abstract

The phylogenetic history, paleontological implications, and ecology of larger New Zealand Recent species of Neilo (sensu stricto) are discussed. N. wairoana delli, N. blacki, and N. (Pseudomalletia) aoteana are described as new. The following taxa are reduced to chronosubspecies: N. jugifera Marwick - of N. australis (Quoy & Gaimard); N. annectens Powell and N. rugata Dell - of N. sublaevis Marwick; N. sinangula Finlay - of N. awamoana Finlay.  相似文献   

15.
《Journal of bryology》2013,35(3):369-375
Abstract

T. bealeyensis R. Br. ter, is reduced to synonymy with T. anderssonii Ångstr. and T. paehyneura Dix. to synonymy with Barbula ealobolax C. Müll.B. calobolax and B. calobolax var. angustinervia C. Müll. are transferred to the genus Willia. T. petriei Broth. is reduced to a subspecies of T. arenae (Besch.) Broth. Differences between this taxon and the ssp. arenae are outlined and T. arenae ssp. arenae is reported for the first time from the Auckland Islands. A lectotype is chosen for T. rubra Mitt, and T. subantaretiea Sainsb. is reduced to a variety of T. rubra. New Zealand plants referred to T. serrulata Hook. et Grev. are more correctly assigned to T. serrata Dix., which is endemic to New Zealand.  相似文献   

16.
Abstract

Rectal body temperatures (BTs) of tuataras (Sphenodon punctatus) and of endemic, ovoviviparous gekkonid lizards—mainly Hoplodactylus maculatus (=H. pacificus) and Heteropholis manukanus—were taken together with ambient temperatures during early summer 1970 in areas of central New Zealand. The results, combined with earlier data, enable a number of conclusions to be drawn. (a) The preferred body temperature of heliotherm reptiles is best deduced from the mode of rectal BTS taken in the field, but that of non-heliotherms, when unimodal, from the median or mean. (b) Among Gekkonoidea, specific thermal relations are highly variable in several ways. (c) Sphenodon foraged on cool nights at BTs of 10.5–12.5°c, yet basked in the forest by day at BTs up to 24°c; in pasture it apparently basks within the burrow entrance. (d) Similarly, H. maculatus foraged at night at BTs of 10–13°c, but by day thermoregulated at BTs up to 33°c by ‘indirect basking’ (under thin cover) or ‘protected basking’ (in crevices penetrated by solar radiation). The average BT of females was 2°c higher than that of males, presumably because many females were gravid. (e) H. manukanus is (tertiarily) diurnal, and thermoregulated by basking up to a BT of 31 °c. Towards evening it apparently cooled down voluntarily. (f) Whereas a high daytime BT probably assists digestion in nocturnal foragers, a voluntary low night-time BT in diurnal reptiles may help to conserve energy.  相似文献   

17.
The Balanophoraceae is a unique angiosperm family that fully parasitizes the roots of trees. Although the pollination systems of several genera in this family have been reported, little is known of their diversity. In the present study, we investigated the pollination biology of Thonningia sanguinea (Balanophoraceae) in the tropical rainforests of Guinea, West Africa. Female flies of the families Muscidae and Calliphoridae as well as Technomyrmex ants frequently visited flowers to consume nectar secreted from inflorescences. While feeding, their bodies attached to anthers or pollen grains. The most abundant flower‐visiting fly, Morellia sp. (Muscidae), was observed laying eggs on T. sanguinea, and the larvae fed only on the vegetative tissue of decaying male inflorescences. Our findings provide a new candidate of pollination mutualism involving plants that provide brood sites for their pollinators.  相似文献   

18.
Abstract

Opportunistic sightings and strandings of Caperea marginata (n=196) from the vicinity of Australia and New Zealand (1884 to early 2007) were used to relate geographic and temporal patterns to oceanographic and broad-scale climatic variability. Records were not uniformly distributed along the coast and more (69%) were from Australia than New Zealand. Seven coastal whale ‘hotspots’ were identified which accounted for 61% of records with locality data. Half of the hotspot records were from southeast (37) and northwest (20) Tasmania—others each had 9–15 events. Upwelling and/or high zooplankton abundance has been documented near all whale hotspots. Records of C. marginata occurred in all months, with 75% in spring and summer. Inter-annual variability showed broad agreement between increased whale records (usually in spring/summer) and strongly positive ‘Niño 3.4’ during 1980–1995 but not thereafter. Coastal upwelling and productivity increase during climatic phenomena such as El Niño and are likely to be quickly beneficial to plankton-feeding whales such as C. marginata.  相似文献   

19.
The wild relatives of bread wheat ( Triticum aestivum ) are valued by plant breeders for their genetic diversity. However, increasing levels of nitrogen (N) deposition and ground‐level ozone (O3) threaten plant biodiversity in the Mediterranean and Near‐East, a hotspot for many crop wild relatives. Knowledge of the effect of these air pollutants in combination is still limited, but early indications are that effects vary depending on the level of pollutants, and on the sensitivity of the species to N and O3. This study examined the responses of four important wheat wild relatives ( Aegilops tauschii , Aegilops speltoides , Triticum dicoccoides and Triticum monococcum ) and one modern wheat cultivar ( T. aestivum ‘Cadenza’) to treatments of N (equivalent to 50 kg ha?1 year?1 ammonium nitrate) and O3 (100 ppb for 21 days), alone and in combination. Measurements included root, shoot and seed biomass, and electrolyte ratios. The O3 sensitivity of A. tauschii and T. aestivum ‘Cadenza’ were exacerbated by the addition of N, while A. speltoides was found to be nitrophilous, with N ameliorating the negative effect of O3. Both T. aestivum ‘Cadenza’ and T. dicoccoides produced immature seed heads, with the cultivar's seed head biomass reduced in response to O3 and N + O3 while that of T. dicoccoides was largely unaffected. These data suggest that all four wild relatives are likely to be affected when N and O3 air pollutants co‐occur, and there in situ populations may therefore be at risk. Equally, the results of this study can inform use of their beneficial traits by wheat breeders, and alert them to the inadvertent inclusion of N and O3 sensitivity.  相似文献   

20.
《Journal of bryology》2013,35(1):12-19
Abstract

Scotland’s mountains are home to a rare and unique liverwort community, ‘the oceanic-montane liverwort-rich heath’, but its component species are absent from regions where they could potentially thrive. Many biological characteristics of these species are unknown, making it impossible to explain the reasons for their rarity; however, they have not been observed to produce sporophytes within Britain. We use ex situ cultivation of whole liverworts and fragments, and in situ cultivation of fragments, to assess the growth rate and the potential for vegetative reproduction of several species. Most of the species grew from both fragments and as whole plants, indicating that the rarity of the liverwort heath is not due to poor powers of regeneration. We propose that growth rate and the potential to regenerate from fragments are important factors structuring the liverwort heath community, at least locally. Furthermore, this study demonstrates that there is potential for ex situ conservation of rare liverwort species, in situ enhancement of existing populations, and creation of new ones.  相似文献   

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