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101.
The monophyly and phylogenetic relationships of the subfamily Microweiseinae were investigated. Twenty‐three in‐group taxa, representing all known genera of Microweiseinae (except for Microcapillata Gordon) were included in a cladistic analysis, based on 45 adult morphological characters. The parsimony analysis of the resulting data matrix supported the monophyly of Microweiseinae, Carinodulini, Serangiini and Microweiseini (inclusive of Sukunahikonini). The recognition of Sukunahikonini renders Microweiseini paraphyletic, and consequently both tribes were synonymized, retaining Microweiseini as a senior family‐group name ( syn.n. ). Genera and tribes of Microweiseinae are diagnosed thoroughly, illustrated and keys to their identification are provided. The following nomenclatural changes were made: Hikonasukuna Sasaji and Orculus Sicard are synonymized with Scymnomorphus Weise ( syn.n. ); Gnathoweisea Gordon is synonymized with Microweisea Cockerell ( syn.n. ); Hikonasukuna monticola Sasaji and Orculus castaneus Sicard are transferred to Scymnomorphus ( comb.n. ); Smilia planiceps Casey, Gnathoweisea hageni Gordon, Gnathoweisea ferox Gordon, Gnathoweisea micula Gordon and Gnathoweisea texana Gordon are transferred to Microweisea ( comb.n ). Three new genera are described: Allenius gen.n. for Allenius californianus sp.n. (type species) from Mexico and Allenius iviei sp.n. from U.S.A.; Gordoneus gen.n. (type species Gnathoweisea schwarzi Gordon from U.S.A.); and Cathedrana gen.n. (type species Cathedrana natalensis sp.n. from South Africa). The first African member of Carinodulini, Carinodulina ruwenzorii sp.n. is described. The genera Microweisea, Coccidophilus, Serangium and Delphastus are well‐known predators of sternorrynchous Hemiptera, such as scale insects (Diaspididae) and whiteflies (Aleyrodidae), and play a significant role in agricultural ecosystems as biocontrol agents. Host data and biological records are summarized for each genus. 相似文献
102.
Eleven species of larval digeneans are reported for the firsttime in the UK from the freshwater snail Lymnaea (Radix) auricularia.The latter replaced its congener L. peregra in a gravel pitnear Wraysbury, Berkshire in the Lower Thames Valley and hostedan assemblage of larval digeneans similar to that previouslytransmitted by L peregra. The larval digeneans of L. peregrain small bodies of water in the area were also similar to thosefound in L. auriculania in the gravel pit. This replacementin the role of the host is explained on the basis of morphological,physiological and ecological similarities of the two lymnaeidspecies. (Received 19 February 1992; accepted 27 April 1992) 相似文献
103.
ADAM F. A. PELLEGRINI CONSTANCE M. SOJA CHULUUN MINJIN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(1):46-61
Pellegrini, A.F.A., Soja, C.M. & Minjin, C. 2011: Post‐tectonic limitations on Early Devonian (Emsian) reef development in the Gobi‐Altai region, Mongolia. Lethaia, Vol. 45, pp. 46–61. This study investigates a Lower Devonian (Emsian) carbonate sequence from the Chuluun Formation where it is exposed in the Gobi‐Altai region of southern Mongolia. Quantification of abundance patterns across guild, morphotype and general taxonomic levels was based on stratigraphical and thin‐section analyses. Comparison with other Emsian carbonate platforms allowed the factors that influenced community development in the wake of a tectonic perturbation to be determined. Our evidence reveals that potential reef‐building biotas preserved in the Chuluun Formation experienced rapid colonization of a newly submerged carbonate platform following an episode of tectonic uplift and the development of a coastal alluvial fan. Although critical reef‐building organisms were present, colonial corals and stromatoporoids exhibited limited vertical growth and showed no significant lateral expansion of individuals or biotic assemblages. Nor did those taxa experience significant increases in abundance, density, or size. We conclude that incomplete succession and the lack of reef development occurred most likely because of an unsuitable substrate, limited accommodation space and isolation that reduced colonization potential. □Community succession, Emsian, palaeoecology, reef suppression. 相似文献
104.
The phylogeny of the 'higher' temnospondyls (Vertebrata: Choanata) and its implications for the monophyly and origins of the Stereospondyli 总被引:1,自引:1,他引:0
A parsimony analysis of 'higher' temnospondyls (all temnospondyls descended from the common ancestor of Eryops and Parotosuchus ) was performed using 37 terminal taxa and 121 osteological characters. Bremer support values for each internal node were calculated as a measure of clade strength. Additionally, the shortest trees that conformed to some alternative hypotheses were searched for. The following new taxa are established on the basis of the results: Euskelia (the clade containing the Eryopoidea and Dissorophoidea), Limnarchia (the clade containing Trimerorhachidae, Dvinosauroidea, Archegosauroidea and Stereospondyli), Dvinosauria (the clade containing Trimerorhachidae and Dvinosauroidea), Stereo-spondylomorpha (the clade containing Archegosauroidea and Stereospondyli), Capitosauria (the clade containing Lydekkerina and 'capitosauroids'), and Trematosauria (the clade containing Trematosauroidea, Rhytidosteidae, Plagiosauroidea, Metoposauroidea and Brachyopoidea). The monophyly of the assemblage of Mesozoic families called the Stereospondyli by Romer is supported. The dominance of the Stereospondyli in the Mesozoic and its rarity in the Palaeozoic is discussed. It is suggested that the radiation of the diverse stereospondyl clades, the Capitosauria and Trematosauria, began in the Late Permian of Gondwana, in a 'safe haven' that was less severely affected by the Late Permian extinction event. It is further speculated that the 'safe haven' was located in Antarctica, or possibly Australia. 相似文献
105.
ADAM URBANEK PIOTR MIERZEJEWSKI BARRIE RICKARDS 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1986,19(2):97-107
Graptoblasts are redefined as widenings of the sealed terminal portions of graptolite stolothecae resulting in ovoid bodies composed of an outer fusellar layer, named here as blastotheca, and an inner secondary layer of electron dense material, named the blastocrypt. In their proximal portion a number of graptoblasts display a scar with fuselli stripped and the crassal material of the blastotheca exposed and displaying a rough and dull surface. The boundary of this area, termed the talus, is edged by a distinct escarpment, probably the margin of the preserved part of the blastotheca. The outer wall of the talus is usually abruptly terminated. Only exceptionally is the outer wall conical and gradually widening. Thus the transverse partition between the parental stolotheca and the graptoblast was produced by the blastocrypt without fusellar covering. It seems, therefore, that graptoblasts were most probably lacking any internal portion of their blastothecae which could possibly be compared with the internal parts of a dendroid auto-theca. It is concluded that graptoblasts housed a zooid that never functioned as an autozooid, but suffered arrested development and encystation. The biological role of graptoblasts as dormant bodies is discussed. 相似文献
106.
ADAM T. FORD ANTHONY P. CLEVENGER ANDREW BENNETT 《The Journal of wildlife management》2009,73(7):1213-1222
ABSTRACT Wildlife crossing-structures (e.g., underpasses and overpasses) are used to mitigate deleterious effects of highways on wildlife populations. Evaluating performance of mitigation measures depends on monitoring structures for wildlife use. We analyzed efficacy of 2 noninvasive methods commonly used to monitor crossing-structure use by large mammals: tracking and motion-activated cameras. We monitored 15 crossing-structures every other day between 29 June and 24 October 2007 along the Trans-Canada Highway in Alberta, Canada. Our objectives were to determine how species-specific detection rates are biased by the detection method used, to determine factors contributing to crossing-event detection, and to evaluate the most cost-effective approach to monitoring. We detected 3,405 crossing events by tracks and 4,430 crossings events by camera for mammals coyote-sized and larger. Coyotes (Canis latrans) and grizzly bears (Ursus arctos) were significantly more likely to be detected by track-pads, whereas elk (Cervus elaphus) and deer (Odocoileus sp.) were more likely to be detected by cameras. Crossing-event detection was affected by species, track-pad length, and number of animals using the crossing structure. At the levels of animal activity observed in our study our economic analysis indicates that cameras are more cost-effective than track-pads for study durations >1 year. Understanding the benefits and limitations of camera and track-pad methods for monitoring large mammal movement at wildlife crossing-structures will help improve the efficiency of studies designed to evaluate the effectiveness of highway mitigation measures. 相似文献
107.
108.
ADAM SHUTTLEWORTH STEVEN D. JOHNSON 《Botanical journal of the Linnean Society. Linnean Society of London》2012,168(3):278-299
Pollinator‐mediated convergence in floral traits is the fundamental basis for pollination syndromes, but it has seldom been rigorously analysed. Here we synthesize information on a guild of South African plants that are pollinated by functionally similar pompilid wasps in the genus Hemipepsis and investigate the extent of trait convergence in guild members. The guild includes members from three plant families (Apocynaceae, Orchidaceae and Asparagaceae subfamily Scilloideae) and contains remarkably high levels of functional specialization with 18 of the 23 known guild members being pollinated exclusively by Hemipepsis wasps. The distribution of the guild is centred in the moist upland grasslands of eastern South Africa. Qualitative similarities among guild members include dull greenish‐ or brownish‐white flowers, often with purple blotches, mid‐summer flowering, sweet spicy scent and exposed nectar. To assess the extent of convergent evolution within the guild, we compared floral traits of guild members with those of congeneric non‐wasp‐pollinated species. Guild members typically produce moderate volumes (> 4 µL per flower per day) of concentrated (> 50% sugar by weight) sucrose‐dominant nectar. The nectar properties of guild members did not, however, differ significantly from those of congeneric species pollinated by other vectors. Non‐metric multidimensional scaling of scent data for 15 guild members and 17 congeners (obtained through gas chromatography–mass spectrometry of headspace samples and supplemented with published data) yielded little evidence for convergent evolution in the overall scent composition of guild members. However, convergence in floral spectral reflectance was evident in the guild members; in particular, loci for colours of guild members were significantly closer to the guild centroid than loci for colours of congeners, and they formed a distinct cluster in the blue to blue–green region of the hymenopteran colour hexagon. The colours of guild members were also significantly closer to the colour of background vegetation than those of congeneric species, suggesting a role for cryptic colouring in this system. These results confirm convergence in the floral colours of plants that are pollinated by Hemipepsis spider‐hunting wasps, but also suggest that other traits, such as nectar properties, do not necessarily evolve during shifts between pollination systems. Identification of particular scent compounds and non‐sugar nectar constituents that influence wasp behaviour will be essential for illuminating the extent of biochemical convergence in the guild members. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 278–299. 相似文献
109.
Species-richness (recorded as number of species in 16 m2 quadrats), in more than 60 coastal sites developed over various substrata, exhibited a significant non-linear relationship with soil total phosphorus extracted from associated soil samples. Although the general form of this relationship is not incompatible with a resource competition model, the significant proportion of the total variance accounted for by the species-richness/phosphorus relationship suggests that a more detailed examination of phosphorus use at a community level will be profitable. 相似文献
110.
Testing Tropiduchini Stål 1866 (Hemiptera: Tropiduchidae) monophyly,a young inter‐tropical taxon of mainly insular species: taxonomy,distribution patterns and phylogeny,with the description of a new genus from Papua New Guinea 下载免费PDF全文
RONG‐RONG WANG XIN‐YU LI JACEK SZWEDO ADAM STROIŃSKI AI‐PING LIANG THIERRY BOURGOIN 《Systematic Entomology》2017,42(2):359-378
A morphological phylogenetic analysis of the tribe Tropiduchini (Hemiptera: Tropiduchidae) is provided for 21 genera among the 26 recognized, including the new genus Oechalinella Wang gen.n. , with a new species Oechalinella bifasciata Wang sp.n. Monophyly of the tribe is well supported by synapomorphies derived from the male genitalia. The strict consensus supports two subclades: ((Montrouzierana + Thymbra) + Thaumantia+) as sister to the clade (Leptovanua + (Vanua + Varma+) + Daradacella+). In the first subclade, the clade (Montrouzierana + Thymbra), distributed in New Caledonia and Papua New Guinea, is well supported by three synapomorphies based on the tegmina, while the Thaumantia+ group is characterized by the conformation of the anal tube and male gonostyli, and distributed from Malesia to Papuasia and in Central Africa. The second subclade is largely distributed from China to Malesia, Papuasia, Southwestern and the Northwestern Pacific islands. The position of the genus Leptovanua remains uncertain. The Varma+ clade is recovered in all analyses. Implied weighting analysis placed the Varma+ lineage as sister to all other genera forming a new group (Leptovanua+ + ((Montrouzierana + Thymbra) + Thaumantia+)). Fennah's definition of Tropiduchini is reviewed according to the phylogenetic results and an identification key to all genera is provided with a referenced synopsis of their distribution. Globally, Tropiduchini exhibits an inter‐tropical latitudinal distribution and a paradoxical bimodal longitudinal distribution pattern in continental Africa, South‐east Asia and the Pacific islands. Distribution data concern nearly 80% of insular taxa. The phylogenetical results suggest that: (i) the tribe originates from continental China; (ii) it evolved mainly from Papuasia by stepping‐stone colonization events, promoting subsequent insular speciation; and (iii) its evolution has mainly been directed by dispersion versus vicariance. 相似文献