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51.
通过形态特征的测量和线粒体DNAcyt b基因序列分析,发现了弹涂鱼属的1个中国新纪录种,大鳍弹涂鱼Periophthalmus magnuspinnatus.新纪录种与中国近缘种弹涂鱼P.modestus的主要形态区别为:第1背鳍大而高,第1鳍棘呈丝状延长,各鳍棘尖明显伸出鳍膜;第2背鳍各鳍棘中部以下颜色均一,无黑斑;第1背鳍和第2背鳍基部之间间距较小;左右腹鳍基部愈合处凹陷较浅.序列分析表明,新纪录种与形态近似种弹涂鱼P.modestus的cyt b基因全序列平均K 2-P遗传距离高达17.3%,在分子系统树上也聚为分别属于两个不同的支序,证实了新纪录种的有效性.新纪录种在中国的渤海、黄海、东海和南海的沿海都有分布记录. 相似文献
52.
A set of 154 accessions of nine wild Lycopersicon spp. and five accessions of three closely related Solanum spp. were tested for resistance to tomato powdery mildew ( Oidium lycopersici ). Screening revealed valuable sources of resistance, mainly among L. hirsutum, L. pennellii, L. cheesmanii, L. chilense, L. peruvianum and L. parviflorum. L. esculentum (all ssp.) and L. pimpinellifolium expressed high susceptibility to O. lycopersici inoculation. Results of variance and cluster analysis of responses to O. lycopersici coincide with recent taxonomic classification and genetic relationships within genus Lycopersicon . 相似文献
53.
中国斑粉蝶属分类研究(鳞翅目:粉蝶科) 总被引:2,自引:0,他引:2
系统地整理了中国斑粉蝶属DeliasHübner,1819的全部种类,共11种31亚种,包括3个中国
新记录亚种:倍林斑粉蝶指名亚种D. berinda berinda Moore、洒青斑粉蝶不丹亚种D.Sanaca bhutya Talbot和侧条斑粉蝶帕瓦亚种D. lativitta parva Talbot。提出将D.Lativitta tai Yoshino作为侧条斑粉蝶云南亚种D. lativitta yunnana Talbot的同物
异名,D. patrua guiyangensis Zhou et Zhang作为Delias berinda adelma
Mitis的同物异名。阐述了各亚种的主要识别特征及其地理分布,分析了区系成分,并提供了分
种检索表及全部种类的雄外生殖器和大部分种类的雌性外生殖器特征图。附有3新记录亚种和国
内未见标本记载的2种的成虫彩色照片 相似文献
54.
55.
The tarsus of erythrosuchid archosaurs, and implications for early diapsid phylogeny 总被引:1,自引:0,他引:1
DAVID J. GOWER 《Zoological Journal of the Linnean Society》1996,116(4):347-375
The morphology of the erythrosuchid ankle joint is reassessed. Two specimens, recently thought to have been incorrectly referred to Erythrosuchus africanus , are shown without doubt to belong to this taxon. Furthermore, the morphology is essentially similar to that of other early archosaurs. The tarsus of Erythrosuchus is poorly ossified and consists of a calcaneum, astragalus, and two distal tarsals. The calcanea of Erythrosuchus, Vjushkovia triplicostata , and Shansisuchus shansisuchus are all similar in being dorsoventrally compressed, possessing a lateral tuber, and lacking a perforating foramen. The astragalus of V. triplicostata is currently unknown. The astragalus of Shansisuchus is apparently unique in form. The erythrosuchid pes is therefore more derived than has been recently proposed. The tarsal morphology of several other archosauromorph taxa is reviewed and many details are found to be at variance with the literature. The plesiomorphic condition for the Archosauromorpha consists of four distal tarsals and a proximal row of three elements; two of which articulate with the tibia. These proximal elements are interpreted as the astragalus, calcaneum, and a centrale, and the same pattern is retained in the earliest archosaurs. This reassessed tarsal morphology has implications for the homology of the centrale and reconstruction of early diapsid phylogeny. 相似文献
56.
水分对有机基质栽培番茄生理特性、品质及产量的影响 总被引:6,自引:0,他引:6
以"齐粉"番茄品种为试材,研究了不同相对含水量对有机基质栽培番茄生长、生理特性、产量、品质和水分利用率的影响.结果表明:随着有机基质相对含水量的升高,番茄株高、茎粗、节间长和单株叶面积极显著增加,叶片色素含量、水势、渗透势及根系活力和果实产量显著增加,而番茄果实品质和水分利用率显著降低.从果实产量、品质和水分利用率方面综合考虑,80%基质相对含水量处理的果实产量达26 kg.m-2以上,可作为番茄有机基质栽培水分管理的量化指标;如果仅考虑果实品质,则50%基质相对含水量可以作为水分管理指标. 相似文献
57.
Phenotypic plasticity is the environmental modification of genotypic expression
and an important means by which individual plants respond to environmental heterogeneity.
The study of phenotypic plasticity in the genus Adenophora, which is very complicated taxo nomically because of great morphological variation, proves to be helpful in both investigating
the phenotypic variation so as to evaluate potential taxonomic value of their characters and
providing important sources of information on the variation, adaptation and evolution of the
genus. Twenty-three populations representing all the six species in Adenophora potaninii
complex were transplanted into the garden. Of them six populations were selected for study ing their performance in the field and in the garden, in addition to cultivation experiment
under different treatments. The results show that there exists considerable developmental
plasticity in some leaf, floral and capsule characters. In particular, the leaf shape and length
of calyx lobe display significant developmental variation with the maximum being three times
as great as the minimum, which is noteworthy because they were previously considered as
diagnostic. The characters of root, caudex, stem and inflorescence are found to be very
plastic, especially the root diameter, the number of stems, stem height and inflorescence
length with great environmental plasticity. In addition, the populations from different habi tats show distinct amounts of plasticity. On the contrary, the characters of leaf, floral, cap sule and seed are less influenced by environments. It seems that the considerable variation in
the characters of leaf is attributed mainly to genetic differences. Finally, the phenotypic
plasticity of morphological characters of A. potaninii complex and its taxonomic significanceis discussed. 相似文献
58.
59.
Mark N. Puttick 《Biology letters》2016,12(8)
Ancestral state reconstruction of discrete character traits is often vital when attempting to understand the origins and homology of traits in living species. The addition of fossils has been shown to alter our understanding of trait evolution in extant taxa, but researchers may avoid using fossils alongside extant species if only few are known, or if the designation of the trait of interest is uncertain. Here, I investigate the impacts of fossils and incorrectly coded fossils in the ancestral state reconstruction of discrete morphological characters under a likelihood model. Under simulated phylogenies and data, likelihood-based models are generally accurate when estimating ancestral node values. Analyses with combined fossil and extant data always outperform analyses with extant species alone, even when around one quarter of the fossil information is incorrect. These results are especially pronounced when model assumptions are violated, such as when there is a trend away from the root value. Fossil data are of particular importance when attempting to estimate the root node character state. Attempts should be made to include fossils in analysis of discrete traits under likelihood, even if there is uncertainty in the fossil trait data. 相似文献
60.
中国蟾蚱属分类研究(蚱总科,短翼蚱科) 总被引:1,自引:0,他引:1
系统研究了分布于我国的蟾蚱属种类,共计10种,其中有2新种,即贵州蟾蚱Hyboella guizhouensis sp.nov.及长翅蟾蚱Hyboella longipennis sp.nov.,并列出我国蟾蚱属分种检索表.模式标本保存于陕西师范大学动物研究所. 相似文献