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1.
Diatom communities from the sub-Antarctic Prince Edward Islands: diversity and distribution patterns
During an extensive survey of the freshwater and moss-inhabiting diatoms of the Prince Edward Islands, a total of 214 taxa
belonging to 60 genera were found. Three main communities can be found on the two islands. A large part of the samples was
grouped into an aquatic group, bringing together all samples from lentic and lotic waterbodies. A second, contrasting, group
was formed by all dry samples whereas in a third group all habitats with higher mineral contents were found. The habitats
differed clearly in taxa composition reflecting that way possible environmental differences. Although the diatom composition
between the two islands of this island group (Marion and Prince Edward Island) showed some minor qualitative differences,
no marked quantitative differences have been observed. The diatom flora shows a distinct similarity with the other islands
in the southern Indian Ocean, such as the Crozet archipelago and the Kerguelen Islands forming a biogeographical entity in
this part of the ocean, distinctly separated from the non-marine diatom flora in other parts of the (sub-)Antarctic Region. 相似文献
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Eulerian time-series were completed at three sites on the south eastern shelf of the Sub-Antarctic Prince Edward Islands (PEI),
from 9 to 27 April 2000, to investigate the spatial and temporal variability of mesozooplankton communities in relation to
on-shelf hydrodynamics. Surface temperature and phytoplankton biomass were recorded daily at all three sites, while two Bongo
net tows and vertical temperature profiles were collected daily at two sites. Contrary to predictions of on-shelf water retention
at low ambient current velocities, cross-correlation analysis identified a northward advection of ∼8.23 cm s−1 over the study area. Day to day changes in both physical and biological parameters were associated with cross-shelf advection.
However, sea temperature had a narrow range of 6.2–7.4°C, while average between sample Bray–Curtis similarity in zooplankton
communities was high, exceeding 75%. The relatively consistent average sample biomass amounted to ∼494 tonnes dry weight of
mesozooplankton per day being advected onto the south eastern sector of the PEI shelf. We hypothesise that the observed stability
of both physical and biological parameters was due to the Sub-Antarctic Front, with its high volume transport and steep physical
gradients, being far to the north of the islands. Spatial and temporal variability of hydrodynamics on the PEI shelf, and
particularly its relationship to shifting frontal positions, is highlighted as a future research area necessary to quantify
the gross delivery of allochthonous biomass to the PEI ecosystem. 相似文献
4.
SHAUN A. FORGIE SARA L. GOODACRE MARTIN I. TAYLOR BRENT C. EMERSON 《Molecular ecology resources》2006,6(3):820-822
The Canary Island pine weevil Brachyderes rugatus (Wollaston) consists of four allopatric subspecies that are thought to have arisen from several historic colonization events within the archipelago. We have isolated and optimized seven microsatellite loci from Brachyderes rugatus calvus from Gran Canaria. Six of these loci are polymorphic within B. rugatus (11–22 alleles per locus; heterozygosity between 0.43 and 0.84). There is no evidence for heterozygote deficit within populations or for linkage disequilibrium between pairs of loci. These molecular markers are likely to prove useful tools for quantifying the genetic variability of bottlenecked island populations. 相似文献
5.
Comparative nutritional ecology of bryophyte and angiosperm feeders in a sub-Antarctic weevil species complex (Coleoptera: Curculionidae) 总被引:1,自引:0,他引:1
Abstract.
- 1 Highly productive and st,ructurally diverse angiosperm communities occur on sub-Antarctic Marion Island, yet cryptogams are the main source of energy and nutrients for five of the six native weevil species (Curculionidae: Ectemnorhinini) that occur there.
- 2 Previously it has been hypothesized that low-temperature regimes, during the Pleistocene, precluded angiosperm herbivory. This hypothesis was based, inter alia, on the assumption that at low temperatures feeding on bryophytes is more nutritionally advantageous than feeding on vascular plants.
- 3 This assumption was tested by comparing the consumption rate (CR) and approximate digestibility (AD) (mass and energy) of bryophytes and angiosperms in two Dusmoecetes species indigenous to Marion Island.
- 4 The approximate digestibility of Blepharidophyllum densifolium (Scapaniaceae) energy and dry mass were similar for D.marioni Jeannel adults at 5°C and at 10°C. D.similis (C. O. Waterhouse) adults fed Azorella selago Hook (Apiaceae) leaves also had similar AD for food dry mass and energy at 5°C and at 10°C. However, the performance of D.similis on A.selago leaves and flowers at 5°C was better than that of D.marioni on bryophytes at both temperatures.
- 5 Bryophyte feeding does not appear to be nutritionally more advantageous at low temperatures in the sub-Antarctic, nor does angiosperm herbivory appear to be comparatively disadvantageous at low temperatures, although D.similis does not feed on Acaena magellanica (Lam.) (Rosaceae) at 5°C. It seems likely that moss-feeding evolved in response to an absence of angiosperms during glacial periods, rather than because of a nutritional advantage associated with bryophagy at low temperatures.
6.
Karyotypes of three species, Brachyderes incanus, Brachysomus setiger and Paophilus afflatus, belonging to the tribe Brachyderini, were studied using C-banding technique. The species share the same chromosome number 2n = 22 and meioformula n = 10+Xy(p) at all metaphase 1 plates of spermatid division. Some differences between karyotypes were observed in terms of centromere positions and C-band sizes. Most chromosomes are meta- or submetacentric and form a graded series in respect to length. The chromosomes resemble one another in having a rather small amount of heterochromatin restricted to the pericentromeric region and visible as dark stained blocks mainly during early stages of nuclear division. Only in Brachyderes incanus do larger bands occur at mitotic metaphase and diakinesis. These cytogenetic data are in agreement with karyological findings obtained in other species of Brachyderini so far examined. 相似文献
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Roman Borovec Fabrizio Menardo Massimo Meregalli 《Zoological Journal of the Linnean Society》2013,167(2):243-258
The genus Holcophloeus gen. nov. is here proposed to include Trachyphloeus cruciatus Seidlitz, 1868, and two new species native to North Africa, based on a phylogenetic analysis and an evaluation of the diagnostic characters. The taxonomic position of Holcophloeus in relation to the tribes Trachyphloeini Lacordaire, 1863, and Holcorhinini Desbrochers, 1898, is discussed, and the new genus is attributed to the Holcorhinini. Holcophloeus laurae sp. nov. from south‐eastern Morocco and Holcophloeus weilli sp. nov. from northern Libya are described and illustrated and a key to the species of the new genus is given. The lectotype of Trachyphloeus cruciatus Seidlitz, 1868, is designated. The genus Massimiellus Borovec, 2009, is transferred from Trachyphloeini to Holcorhinini. © 2013 The Linnean Society of London 相似文献
8.
CLAUDE MASSIN 《Zoologica scripta》1992,21(3):311-324
Two new species Mesothuria edwardensis sp.n. and Paradota marionensis sp.n., and four little-known species Cucumaria kerguelensis Théel, 1886, Cladodactyla crocea croceoides (Vaney, 1908), Psolidium incertum (Théel, 1886) and Synallactes challengeri (Théel, 1886) of holothurians are described from Marion and Prince Edward Islands. 相似文献
9.
Two curculionid weevils, Orthochaetes setiger (Beck, 1817) and Exomias pellucidus (Boheman, 1834) are recorded in New Zealand for the first time. The former has a wide distribution through the eastern South Island, while the latter has so far only been located in a single suburban garden in Dunedin. Both species are polyphagous and flightless. Although neither is expected to cause notable economic damage, their potential to invade native ecosystems makes them worthy of further investigation. 相似文献
10.
KYUNGDUKHAN RUN-ZHIZHANG YOUNG-GUNPARK 《Insect Science》2005,12(3):217-223
Two new species of the genus Eumyllocerus Sharp, 1896, of the subfamily Entiminae Schoenherr, 1823, are described from China. Eumyllocerus longisetus sp. n. may be distinguished from other species of the genus by its long bristle-like, erect setae on the intervals, each of which is longer than the width of the second interval, the setae arrangedin double rows, and its shell-like, shiny, dense, metallic green scales. Eumyllocerus rotundicorpus sp. n. may be distinguished from any other Eumyllocerus species by its oval and inflated elytral shape, short stout metepisternum, small humeri, elytral setae shorter than 0.5 times the width of the second interval, the setae arranged in double rows, and its golden copper and pearl gray scales. The taxonomy of the genus is discussed. The two new species are described and habitus photographs and figures of diagnostic characters are provided. The type specimens of the new species are deposited in the Institute of Zoology, Chinese Academy of Sciences, Beijing, China (holotype and paratypes) and the Korean Entomological Institute, Korea University, Seoul, Korea (paratypes). 相似文献
11.
Mahmut Erbey 《Zoology in the Middle East.》2013,59(3):241-245
A new species, Rhytideres evrani Erbey sp. n., is described from Inner Anatolia (Turkey), which is closely related to R. plicatus Olivier, 1790.http://www.zoobank.org/urn:lsid:zoobank.org:pub: AF936EEE-D6F2-4830-9D42-35CEF250E066 相似文献
12.
B. A. Korotyaev 《Entomological Review》2017,97(1):90-115
Thirteen new species of the weevil subfamily Ceutorhynchinae are described from the Russian Far East, Azerbaijan, Kazakhstan, Turkmenistan, Uzbekistan, Tajikistan, and Nepal. A new subgen. n. is erected in Oprohinus for O. oxyanus sp. n. (type species) and O. maior sp. n. from Tadzhikistan and Turkmenistan. Ceutorhynchus neophytus Fst. is resurrected from synonymy with C. arator Gyll. Ceutorhynchus gandoni Hoffm. is transferred to Sirocalodes Voss. Rhinoncus fukienensis Wagn. is recorded for the first time from Taiwan, and Oprohinus libanoticus (Schze.)—from Syria. 相似文献
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A molecular phylogeny and lineage age estimates are presented for the Macaronesian representatives of the weevil subfamily Cryptorhynchinae, using two mitochondrial genes (cytochrome c oxidase subunit 1 and 16S). The Bayesian reconstruction is supplemented by observations on morphology, ecology, and reproductive biology. The present study often corroborates the groups previously outlined in higher‐level informal taxonomies. These and further groups are now assigned new taxonomic status. The following genera and subgenera are described (formerly Acalles): Aeoniacalles gen. nov. , Canariacalles gen. nov. , Ficusacalles gen. nov. , Madeiracalles gen. nov. , Silvacalles gen. nov. (with Tolpiacalles subgen. nov. , Tagasastacalles subgen. nov. ), Sonchiacalles gen. nov. , Echiumacalles gen. nov. (monotypic), Lauriacalles gen. nov. (monotypic), and Pseudodichromacalles gen. nov. (monotypic; formerly Dichromacalles). For the western Palaearctic genus Acalles Schoenherr, 1825 the first subgenus Origoacalles subgen. nov. is described and for the genus Onyxacalles Stüben, 1999 the first subgenus Araneacalles subgen. nov. ; Paratorneuma Roudier 1956 resyn. Except for one species of Acalles (Origoacalles), all of these new higher taxa are endemic to the Macaronesian Islands. All new taxa are presented, together with their host plants and further data, in a synoptic tabular overview. Based on the results of our phylogenetic analysis, we advocate the hypothesis that the evolution of the species in the new genera (of which most group into a ‘Macaronesian clade’) began in the comparatively arid succulent bush zone and that the shady and humid laurel forest of the thermo‐Canarian and thermo‐Madeiran zone was entered much later. Our reconstruction implies that the Canarian and Madeiran archipelagos were colonized by Cryptorhynchinae at least seven times from the continent but saw only one considerable adaptive radiation. It also becomes apparent that it is the ancestor species of the genus Canariacalles– and not Pseudodichromacalles– that features a close connection to the south‐western European and north‐western African species of Dichromacalles s.s. Finally, a key is presented for all genera and subgenera of the Macaronesian Cryptorhynchinae. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 40–87. 相似文献
15.
The white-chinned petrel (Procellaria aequinoctialis) is the seabird most often killed on longlines in the Southern Ocean and is listed as vulnerable to extinction. We estimated the population breeding at the Prince Edward Islands, the last breeding site for the nominate subspecies that lacks a recent population estimate. White-chinned petrel burrows are largely confined to deep, muddy soils, usually on slopes below 200?m, but locally up to 420?m. After correcting for count bias, Marion Island has an estimated 29,900 nests (95?% CI 27,700–32,400). Burrow occupancy rates at the start of the incubation period were 65?% during one-off surveys, but repeat surveys found that at least 73?% of burrows were occupied and 87?% of burrows showed signs of occupancy. This suggests that there were roughly 24,000 occupied nests on Marion Island (95?% CI 20,000–28,000). A more cursory survey on Prince Edward Island yielded 14,700 burrows, suggesting that there are 9,000–15,000 occupied nests. The nominate subspecies of white-chinned petrel occupies approximately 974,200 nests (95?% CI 678,000–1,286,000), with the Prince Edward Islands, the third most important breeding site, after South Georgia and Kerguelen. Assuming that populations breeding at islands in the Atlantic and Indian Oceans winter in different regions, the impact of fishery bycatch is likely to have had a greater impact on the Indian Ocean population. The Marion Island survey provides a baseline against which future population changes can be assessed. 相似文献
16.
Arostropsis groehnigen. et sp. n. is described from Baltic amber and temporarily placed in the tribe Naupactini. It differs from all recent Naupactini genera with open corbels by very short and flattened scape, distinct lateral carina of the pronotum and elytra, and the rostrum distinctly narrower than the head capsule. The shape of head in the extinct genus is somewhat similar to that of the extant Naupactini genera with enclosed corbels (Platyomus Sahlberg, 1823 and Aptolemus Schoenherr, 1842), but differs in the slender body, open corbels, very short antennal scape and epifrons without a median sulcus (only a longitudinal depression is slightly visible). It is also similar to the Tanymecine genus Pandeleteius Schoenherr, 1834 in general appearance, but distinct by the straight anterior edge of the pronotum, lack of postocular spurs, lobes, and vibrissae, a slightly sloping elytral declivity, lateral ridges on the pronotum, subflattened antennal scape, elongate rostrum, and sparsely setose epistome. A new synonymy of the generic names Protonaupactus Zherikhin, 1971 and Sucinophyllobius Wanat & Borowiec, 1986, syn. n., is established. The Madagascan genus Corecaulus Fairmaire, 1903 is transferred from the tribe Naupactini to the Brachyderini because of its connate claws and the similarity in chaetotaxy of the epistomal area with African and Madagascar Brachyderini genera. A key to the identification of known Baltic amber genera of Entiminae is proposed. A checklist of the prepleistocene fossil Entiminae, based on V.V. Zherikhin's data, with remarks and corrections, is presented. 相似文献
17.
ASTRID PIZZO ANGELA ROGGERO CLAUDIA PALESTRINI PIERO CERVELLA MASSIMILIANO DEL PERO ANTONIO ROLANDO 《Biological journal of the Linnean Society. Linnean Society of London》2006,89(2):197-211
The present study investigated the morphological and genetic differentiation pattern between two sympatric dung beetle sister species, Onthophagus taurus and Onthophagus illyricus . The geometric morphometric approach coupled with the use of molecular markers allowed examination of the nature of interspecific relationships and an outline of the evolutionary and geographical processes that might have led to interspecific differentiation and the present-day partial sympatric and syntopic pattern of distribution. Geometric morphometrics failed to discrimininate the two species on the ground of external morphological traits, but revealed interspecific differences when the shape of the primary sexual traits was taken into account. The use of two different molecular markers (cytochrome oxidase subunit I gene and amplified fragment-length polymorphism) demonstrates that the two species are genetically well differentiated, forming two distinguishable lineages probably diverged during the Pliocene by allopatric speciation. No evidence of past or recent introgression and no support for hybridization were found, suggesting that sympatry was established subsequently, when speciation was accomplished. Both molecular markers and genital shape indicate that phenotypically intermediate individuals, despite their ambiguous appearance, are members of O. illyricus species rather than hybrids. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 197–211. 相似文献
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Geometric morphometric and phylogenetic analyses of Arizona Sky Island populations of Scaphinotus petersi Roeschke (Coleoptera: Carabidae) 下载免费PDF全文
Scaphinotus petersi Roeschke, 1907 (Carabidae) is a ground beetle endemic to Sky Islands in south‐eastern Arizona. Previous taxonomic studies described several subspecies with morphological differences inhabiting geographically isolated mountain ranges. We combined molecular sequence data and morphometric data, especially head and pronotum shape analyses, to examine the variation and divergence in subspecies and isolated montane populations. In this study, we employ a combination of distance morphometrics as well as geometric morphometrics to quantify the level of morphological variation, and to test the hypothesis that geographically distinct populations of S. petersi are phenotypically distinct. Results suggest that these isolated populations have diverged morphologically and genetically. Phylogenetic analyses identified two monophyletic lineages within the species that correspond generally to pronotum shape. We observed significant morphological variation among most montane populations in of S. petersi, with the pronotum shape as the clearest delimiting trait. © 2015 The Linnean Society of London 相似文献
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21种植物提取物对玉米象的生物活性 总被引:31,自引:3,他引:31
为了筛选对粮库安全的植物源杀虫剂,研究了21种植物的4种溶剂(无水乙醇、丙酮、乙酸乙酯和石油醚)提取物对玉米象Sitophilus zeamais Motschulsky的驱避和触杀作用。结果表明,高良姜Alpinia officinarum石油醚提取物、黄姜Curcuma longa丙酮提取物和山鸡椒Litsea cubeba石油醚提取物对玉米象成虫的驱避作用显著,处理60 h平均驱避等级均达到Ⅴ级,平均驱避率分别为80.02%、80.60%和81.70%。在21种植物中,石菖蒲Acorus gramineus和巴豆Croton tiglium的4种溶剂提取物均对玉米象成虫的触杀作用明显,7.86 mg/cm2的剂量处理4天后的校正死亡率均达到90%以上。 相似文献
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