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11.
The taxonomic status of previously misplaced species of an ant-like stone beetle from Spanish amber (Albian) is clarified. Specimens of Kachinus magnificus (originally placed as incertae sedis within Scydmaenitae) were re-examined and their characters were found different from those of the type species of Kachinus from Myanmar amber. Consequently, Archeutheia gen. nov. is proposed to accommodate the Spanish species, resulting in Archeutheia magnifica comb. nov. Moreover, in a comprehensive phylogenetic analysis Archeutheia was placed as a sister group to extant Eutheia, within the tribe Eutheiini of Cephenniitae. A specimen of an undetermined genus from Myanmar amber clearly belonging in Cephenniini is also recorded. Both taxa represent the first definite Cretaceous Cephenniitae, a supertribe whose recent members are distributed on all continents but are especially diverse in the Oriental and East Palaearctic regions. This finding demonstrates a diversification of two presently most species-rich tribes of Cephenniitae already in Early Cretaceous. Archeutheia is strikingly similar to the extant species of Eutheia and Veraphis, showing male dimorphic characters (modified protrochanters) and antennal cavities characteristic of Palaearctic Eutheiini. This fact suggests a long morphological stability in the supertribe. A previously proposed hypothesis of an early presence of the Cephenniitae in the Northern Hemisphere is for the first time supported by the fossil record, and the palaeolocalities (western Europe and Southeast Asia) demonstrate a wide distribution of Cephenniitae in the Cretaceous and an early split of its ancestral lineage.  相似文献   
12.
为探讨DNA条形码基因COⅠ序列在石鲈亚科鱼类物种鉴定的有效性,本研究分析了印度-太平洋区域的石鲈亚科7个属29种鱼类9个个体长度为651 bp的COⅠ基因序列,利用MEGA 5.0计算石鲈亚科种内与种间的遗传距离,并基于最大简约法与最大似然法构建了其分子系统进化关系。结果显示:石鲈亚科鱼类种间遗传距离在0.021—0.240之间,平均遗传距离0.184;种内遗传距离在0.000—0.009之间,平均0.004。其中种间平均遗传距离(0.184)显著大于种内平均遗传距离(0.004),种间遗传距离是种内的46倍。同时,各物种间遗传距离均大于Hebert推荐区分物种的最小种间遗传距离0.02(2%)。基于COⅠ序列构建的系统进化树,同一物种不同个体间均能聚成独立的单系,表明COⅠ基因可作为石鲈亚科物种准确鉴定的有效条形码基因。同时,系统进化树上,石鲈属是非单系类群,主要形成5个分支,而不同分支的种类与其地理分布存在一定的相关性,与近年部分分子系统地理学的研究观点一致。  相似文献   
13.
A study was undertaken to investigate the heterotrophic bacterial flora associated with the sea anemones. Samples of the sea anemones Anthopleura midori were collected from the coast of Weihai and bacteria were isolated from these samples. Additionally, high numbers of viable bacteria were obtained from the celom wall and surface of anemone, the community of cultivable bacteria was very diverse. As a result of this isolation, 60 strains were obtained, 56 of them were selected for identification and characterization by 16S rRNA gene sequence analysis and limited phenotypic testing. Among these isolates, 16 strains were phylogenetically related to members of the genus Pseudoalteromonas and neighboring taxa. Other isolates included members of the genera Colwellia, Vibrio, Acinetobacter, Pseudomonas, Endozoicomonas, Roseovarius, Paracoccus, Loktanella, Leisingera, Sulfitobacter, Bacillus, Staphylococcus, Plantibacter, Microbacterium, Micrococcus, Joostella, Psychroserpens, Cellulophaga, Krokinobacter, Polaribacter and Psychrobacter. Seven potential novel species were found. Among 60 strains, 17 of them can produce proteolytic exoenzyme, 20 can produce lipolytic exoenzyme. Strain NQ8 has strong antagonistic effects on some Vibrio strains. This study demonstrates that the culturable fraction of bacteria from the sea anemones Anthopleura midori is diverse and appears to possess much potential as a source for the discovery of novel bioactive materials.  相似文献   
14.
Four new, monotypic genera of Aleyrodidae from the Lower Cretaceous Lebanese amber are described: Shapashe aithiopa gen. sp. nov.; Milqartis azari gen. sp. nov.; Aretsaya therina gen. sp. nov.; and Yamis libanotos gen. sp. nov. All new taxa represent subfamily Aleurodicinae. The key for identification of genera of Aleurodicinae from the Lebanese amber is provided. The morphological features of newly established taxa are discussed. The importance of the fossils for phylogenetic, evolutionary and ecological studies is presented.  相似文献   
15.
正1 Introduction Many soda and salt lakes are characterized by the formation of the meromictic conditions under which a part of the water column is not involved in the annual process of mixing(Mac Intyre,Melack,1982).This creates an  相似文献   
16.
正A Dunaliella strain was isolated from Yuncheng Salt Lake,Shanxi,China(111.05°E,35.03°N).Morphological characteristics and molecular data were used to evaluate the relationship of this algal strain to other Dunaliella  相似文献   
17.
18.
The new genus and species Angustaeshna magnifica of Burmaeshnidae is described on the basis of a new fossil from Burmese amber. The genus Cretaeshna from the same amber is transferred from the Telephlebiidae into the Burmaeshnidae. We redefine this last family, no longer considered as the sister group of the Late Cretaceous Enigmaeshnidae, but as putative sister group of the Telephlebiidae in the Aeshnoidea. No known fossil belongs to the Telephlebiidae.  相似文献   
19.
Eight hundred and thirty eight base pair fragment of mitochondrial COI gene of wild and cultured populations (CP1, CP4, CP5 and CP6) of Fenneropenaeus chinensis was amplified and sequenced. The A, T, G and C contents of the sequence were 235 bp (28.0%), 307 bp (36.6%), 138 bp (16.5%) and 158 bp (18.9%), respectively. Furthermore, 556 bp fragment of the sequence was used to discuss the phylogenetic relationship among 14 Penaeidae species using Alpheus armillatus as the outgroup. From the molecular phylogenetic tree constructed by neighbor-joining method, we obtained three large shrimp groups: Farfantepenaeus, Litopenaeus and Fenneropenaeus group. The results also indicated that there were a closer genetic relationships between F. aztecus and F. paulensis, L. schmitti and L. setiferus, F. indicus and F. merguiensis, and the genus Farfantepenaeus was closer to Litopenaeus.  相似文献   
20.
Two new genera and species belonging to the family Scolebythidae are described from mid-Cretaceous amber of Myanmar, Cursoribythus silvestris and Siccibythus musculosus. These taxa are introduced into the current phylogenetic tree of the family, in order to analyze their relationships and observe their impacts on our understanding of the family. The implication of the findings (this is the first record of the family in the Cretaceous amber deposits of Myanmar) are discussed.  相似文献   
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