叶蝉科昆虫分子系统发育的研究进展

从基因组DNA的提取、研究的基因片段、PCR引物选用、扩增条件以及叶蝉科不同阶元的分子系统发育分析等方面,综述叶蝉科(半翅目:叶蝉科)昆虫分子系统发育的研究进展。目前角顶叶蝉类的研究成果相对较多,大叶蝉亚科次之,其余类群的研究较少或无。线粒体基因与核基因序列联合分析以及线粒体全序列分析以及基因序列与形态数据相结合分析,分子鉴定叶蝉与共生菌之间的协同进化的研究,将是叶蝉分子系统学未来发展的主要研究手段。     

Evolutionary divergence in Dolichopoda cave crickets: A comparison of single copy DNA hybridization data with allozymes and morphometric distances

In this paper we attempt to investigate relationships between the amount of genetic divergence in nuclear genes and the degree of morphological differentiation for different sets of characters in Dolichopoda cave crickets. Six populations representing five Dolichopoda species from Central and Southern Italy have been studied. The overall genetic divergence at nuclear genes was estimated both by single copy DNA-DNA hybridization and allozyme frequencies at 26 loci. Euclidean distances for two multivariate sets of morphometric variables: one describing body and appendage morphology, the other male epiphallus shape. Results showed a close agreement between the branching patterns of ΔTm values from DNA hybridization and Nei's allozyme distance values. On the other hand, patterns of morphological divergence revealed independent trends, although the branching pattern based on epiphallus morphology matched to some extent the phylogenies inferred from molecular data. The relative value of molecular and morphological characters as reliable phylogenetic tracers was evaluated in relation to their dependence on evolutionary factors. Implications of these findings on the calibration of molecular clocks are also discussed. The absolute rate of molecular change based on scDNA was estimated to be at least 0.98% divergence/my/lineage. This result is in agreement with calibrations attempted on other insects. Estimates of time of divergence based on allozymes (Nei's D) were highly consistent with the estimate from geological data.     

A phylogenetic analysis of subtribe Pleurothallidinae (Orchidaceae)

A cladistic analysis of subtribe, Pleurothallidinae (Orchidaceae) is based on 45 anatomical/ morphological characters. The ingroup members comprise 24 genera; the large genus Pleurothallis consists of two subgenera and ten species complexes. Three taxa representing subtribes Laeliinae and Arpophyllinae are designated as outgroup. Eight most parsimonious trees were discovered using computer assisted software (length = 230; CI = 0.27). The hypothesis that subtribe Pleurothallidinae has undergone a unilinear reduction in the number of pollinia is not supported by this study. Although the eight-pollinia state as represented by Octomeria apparently is plesiomorphic, the two-pollinia and four-pollinia states arose early in the phylogeny of the subtribe. Both two-and four-pollinia states subsequently reappeared as parallelisms. The six-pollinia state exhibited in Brachionidium is autapomorphic. This cladistic analysis suggests that Pleurothallis is not a natural genus and, perhaps may be divided into several discrete genera.     

A phylogenetic analysis of subtribe Pleurothallidinae (Orchidaceae)

A cladistic analysis of subtribe, Pleurothallidinae (Orchidaceae) is based on 45 anatomical/ morphological characters. The ingroup members comprise 24 genera; the large genus Pkurothallis consists of two subgenera and ten species complexes. Three taxa representing subtribes Laeliinae and ArpophyUinae are designated as outgroup. Eight most parsimonious trees were discovered using computer assisted software (length = 230; CI = 0.27). The hypothesis that subtribe Pleurothallidinae has undergone a unilinear reduction in the number of pollinia is not supported by this study. Although the eight-pollinia state as represented by Octomeria apparently is plesiomorphic, the two-pollinia and four-pollinia states arose early in the phytogeny of the subtribe. Both two-and four-pollinia states subsequently reappeared as parallelisms. The six-pollinia state exhibited in Brachionidium is autapomorphic. This cladistic analysis suggests that Pkurothallis is not a natural genus and, perhaps may be divided into several discrete genera.     

The Impact of Molecular Methods on the Systematics of Angiosperms

A comparison is made between the systematics of selected orders and families based on morphology and other “classical” characters on the one hand, and the results of molecular methods on the other hand. It can be shown that taxa defined by a broad array of characters from morphology, anatomy, embryology and phytochemistry usually are confirmed by molecular results. On the other hand a family like the Saxifragaceae s.l. delimited solely on the basis of floral morphology has been shown to be grossly polyphyletic. Some quite surprising results of the molecular analyses usually agree with some embryological or phytochemical characters, and sometimes even with characters of vegetative morphology and anatomy. As a special case “unequal ancient splits” are discussed, where one clade contains few genera and species usually retaining many primitive characters, and the other shows great diversity and contains the more advanced members.     

Intergeneric phylogenetic relationships in catfishes of the Loricariinae (Siluriformes: Loricariidae), with the description of Fonchiiloricaria nanodon: a new genus and species from Peru

Recent investigations in the upper Río Huallaga in Peru revealed the presence of an intriguing species of the Loricariinae. To characterize and place this species within the evolutionary tree of the subfamily, a molecular phylogeny of this group was inferred based on the 12S and 16S mitochondrial genes and the nuclear gene F-reticulon4. The phylogeny indicated that this distinctive species was a member of the subtribe Loricariina. Given its phylogenetic placement, and its unusual morphology, this species is described as a new genus and new species of Loricariinae: Fonchiiloricaria nanodon. This new taxon is diagnosed by usually possessing one to three premaxillary teeth that are greatly reduced; lips with globular papillae on the surface; the distal margin of lower lip bearing short, triangular filaments; the premaxilla greatly reduced; the abdomen completely covered by plates, with the plates between lateral abdominal plates small and rhombic; a caudal fin with 14 rays; the orbital notch absent; five lateral series of plates; dorsal-fin spinelet absent; preanal plate present, large and solid, and of irregular, polygonal shape, the caudal peduncle becoming more compressed posteriorly for the last seven to 10 plates.     

Examination of subfamilial phylogeny in Bromeliaceae using comparative sequencing of the plastid locus ndhF

Parsimony analysis of 31 sequences of the chloroplast locus ndhF was used to address questions of subfamilial phylogeny in Bromeliaceae. Results presented here are congruent with those from chloroplast DNA restriction site analysis in recognizing a clade containing Bromelioideae and Pitcairnioideae, and in resolving Tillandsioideae near the base of the family. Placements of several taxonomically difficult genera (e.g., Glomeropitcairnia and Navia) corroborate those of traditional treatments; however, these data suggest that Brocchinia (Pitcairnioideae) is the sister group to the remainder of Bromeliaceae. Further evidence for the paraphyly of Pitcairnioideae includes the resolution of Puya as the sister group to Bromelioideae. Implications for taxonomic realignment at the subfamily level are considered.     

Comprehensive gene and taxon coverage elucidates radiation patterns in moths and butterflies

Lepidoptera (butterflies and moths) represent one of the most diverse animals groups. Yet, the phylogeny of advanced ditrysian Lepidoptera, accounting for about 99 per cent of lepidopteran species, has remained largely unresolved. We report a rigorous and comprehensive analysis of lepidopteran affinities. We performed phylogenetic analyses of 350 taxa representing nearly 90 per cent of lepidopteran families. We found Ditrysia to be a monophyletic taxon with the clade Tischerioidea + Palaephatoidea being the sister group of it. No support for the monophyly of the proposed major internested ditrysian clades, Apoditrysia, Obtectomera and Macrolepidoptera, was found as currently defined, but each of these is supported with some modification. The monophyly or near-monophyly of most previously identified lepidopteran superfamilies is reinforced, but several species-rich superfamilies were found to be para- or polyphyletic. Butterflies were found to be more closely related to ‘microlepidopteran’ groups of moths rather than the clade Macrolepidoptera, where they have traditionally been placed. There is support for the monophyly of Macrolepidoptera when butterflies and Calliduloidea are excluded. The data suggest that the generally short diverging nodes between major groupings in basal non-tineoid Ditrysia are owing to their rapid radiation, presumably in correlation with the radiation of flowering plants.     

关于节肢动物系统分类与进化的分子佐证

从分子系统学方面就了肢动物系统进化及高级阶元分类研究中争论的关键问题进行比较分析。综述了该领域所取得的新进展,着重从分子水平来探讨节肢动物的起源与进化。     

A unifying theory for methods of systematic analysis

A unifying theory for systematic analysis states that a number of methods should be used jointly to cope with various kinds of data; also that groups should be as consistent as possible, be made with least information loss, and where needed, be polythetic. A test of relationship, homogeneity, can use various kinds of data. It can take account of the internal variation of aggregate items such as genera. It can give due emphasis to smaller clusters that have likely important contexts of external items. It helps in analysing trends, cores and hazes in dendrograms. A proposed detector for formal groups can be based on measures of isolation, identifiability and inclusiveness. Non-mathematical, inter-item reaction tests such as hybridization and serology can also be used in grouping. All relationship data are used polythetically to reveal natural groups. This leads to a unified informational concept for taxa. This is more useful than the biological species concept that is restricted to inter-breeding data. All the methods appear to be analogues of the powerful human grouping instinct. The resulting compatibility is important as precise methods are needed mainly when the data are too complex for the mind to use reliably. Cladograms can be made by self-graded deweighting of homogeneity and agglomerative clustering. Unlike classical cladistics this can reveal any polythetic group. Finding the derived states for making cladograms is often much too hypothetical for a fully cladistic approach to be properly precise. Instead, where the evidence is weak, a milder strength of graded deweighting is used for the cladistic properties, which help to show relationships along with the others. Axiomatic failures of other classes of grouping methods are discussed. Unavoidable remnants of instinctive processing lower the precision of all the methods. The Uniter computer program, based on the theory, is tested with finely graded values of artificially ‘evolved’ items and with coarsely coded cladistic data. The results show that with natural data, the program should act as a fairly sensitive probe of past evolutionary branching. Another test shows how specimens from species complexes can be grouped and how distinctions between groups are analysed.     

Naturalists, Molecular Biologists, and the Challenges of Molecular Evolution

Biologists and historians often present natural history and molecular biology as distinct, perhaps conflicting, fields in biological research. Such accounts, although supported by abundant evidence, overlook important areas of overlap between these areas. Focusing upon examples drawn particularly from systematics and molecular evolution, I argue that naturalists and molecular biologists often share questions, methods, and forms of explanation. Acknowledging these interdisciplinary efforts provides a more balanced account of the development of biology during the post-World War II era. This revised version was published online in July 2006 with corrections to the Cover Date.     

The colubrid radiation in Africa (Serpentes: Golubridae): phylogenetic relationships and evolutionary patterns based on immunological data

Phylogenetic relationships among genera of African colubrids were evaluated using estimates of divergence among serum albumins compared by microcomplement fixation. Representatives of about half of the extant genera of African colubrids, as well as the Elapidae, Atractaspis and the Madagascan colubrid Leioheterodon, were analysed. The tree of best fit to the data has an unresolved basal polychotomy comprising at least five lineages of colubrids, as well as Elapidae and Atractaspis; thus, colubrids were not demonstrably monophyletic with these data. Two cosmopolitan clades, colubrines and natricines, are represented in Africa by series of closely related genera, but divergence among other genera is relatively great. Rate tests show that this is apparently not due to higher rates of albumin evolution in these, relative to other colubrids. Among the other associations supported by the immunological data are: (1) Psammophis-(Rhamphiophis-Dipsina)-Malpolon-Psammophylax; (2) Amblyodipsas-Macrelaps; (3) (Lycodonomorphus-Lamprophis)-Mehelya; and (4) Colubrinae-Natricinae. Grayia is questionably associated with the colubrine-natricine lineage. Prosymna and Lycodon are clearly members of the colubrine clade, and Amplorhinus possibly associates with Leioheterodon. Gonionotophis, Duherria, Lycophidion and Pseudaspis show no strong association with any other genera, and represent other basal or near-basal clades within the colubrid/elapid radiation. The immunological data do not support a clade comprising the Elapidae, Atractaspis and some ‘aparallactines’ relative to Viperidae and other colubrids. The basal colubrid-elapid-Atractaspis divergence occurred more than 30 Myr ago, and the fossil record of colubrids in Africa greatly underestimates both the age and clade diversity of this group. In contrast to the pattern of radiation in the neotropics, where most colubrids belong to one of three major clades, in Africa only the colubrine lineage comprises a substantial portion of the extant generic diversity; most other genera stem from relatively ancient cladogenetic events and have few living representatives.