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421.
GREGORY W. COURTNEY 《Systematic Entomology》1991,16(2):137-172
Abstract. A cladistic analysis of the Blephariceromorpha (here including the Nymphomyiidae, Deuterophlebiidae and Blephariceridae) and related Diptera provides a test of the phylogenetic hypotheses of Rohdendorf (1964, 1974), Hennig (1973), Wood & Borkent (1989) and Courtney (1990a). In particular, monophyly of the Blephariceroidea and Blephariceromorpha (sensu Wood & Borkent), and their relationship to other Diptera, is tested. Evaluation of larval, pupal and adult characters supports the hypothesis of Wood & Borkent, as modified by Courtney. Four larval features suggest that the Blephariceromorpha + Psychodomorpha form a monophyletic group, although an alternate hypothesis predicting that the Blephariceromorpha is the sister group of the Psychodomorpha + (Ptychopteromorpha + Culicomorpha), is discussed. Monophyly of the Blephariceromorpha (Nymphomyioidea + Blephariceroidea) is supported by one adult and five larval characters. Monophyly of the Blephariceroidea (Deuterophlebiidae + Blephariceridae) is supported by thirteen synapotypies, including features of the larva (six), pupa (three) and adult (four). Nineteen, nineteen and nine hypothesized synapotypies support monophyly of the Nymphomyiidae, Deuterophlebiidae and Blephariceridae, respectively. 相似文献
422.
GREGORY D. EDGECOMBE BRIAN D. E. CHATTERTON 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1987,20(4):337-351
Divergence of Silurian encrinurine trilobite clades from common ancestry may be modelled as hetero-chronic pattern. Comparing ontogenies of ancestral late Ordovician Encrinuroides and the descendant punctarus and uariolaris plexi of Silurian Encrinurus provides a test of this hypothesis. Heterochrony in the punctarus plexus is dissociated with respect to entire organisms, but regionally global throughout cranidia (paedomorphic states) and pygidia (peramorphic states). Regulatory dissociation may explain the apomorphous enrollment strategy of this group. The uariolaris plexus, for which a growth series of Balizoma dimitroui (Perry & Chatterton) provides ontogenetic data, shows a complex of peramorphic cephalic character states. Changes in developmental timing thus provide a mechanism by which morphologic and ecologic divergence of closely-related clades was catalyzed in the Llandovery encrinurine radiation. Paedomorphic and dissociated Lineages of the odontopleurid Leonaspis provide a comparable example of divergent heterochronic pattern associated with coexisting (in the same biofacies) species of comparatively recent common ancestry. 相似文献
423.
A sulfur-containing lipid with chromatographic properties in several systems equal to the commercial sulfolipid (extracted from bovine spinal cord, Applied Science) has been isolated in 0.6 % yield (dry weight basis) from the mycelia of Glomerella cingulata. About 35 % of exogenous Na35SO4 incubated with the mycelial medium for 72 hours was recovered in the cerebroside sulfate fraction, with only traces of 35S activities in other lipid fractions. 相似文献
424.
Phylogeny of Trichomonads Inferred from Small-Subunit rRNA Sequences 总被引:13,自引:0,他引:13
JOHN GUNDERSON GREGORY HINKLE DETLEF LEIPE HILARY G. MORRISON SHAWN K. STICKEL DAVID A. ODELSON JOHN A. BREZNAK THOMAS A. NERAD MIKLOS MÜLLER MITCHELL L. SOGIN 《The Journal of eukaryotic microbiology》1995,42(4):411-415
ABSTRACT. Small subunit (16S-like) ribosomal RNA sequences were obtained from representatives of all four families constituting the order Trichomonadida. Comparative sequence analysis revealed that the Trichomonadida are a monophyletic lineage and a deep branch of the eukaryotic tree. Relative to other early divergent eukaryotic assemblages the branching pattern within the Trichomonadida is very shallow. This pattern suggests the Trichomonadida radiated recently, perhaps in conjunction with their animal hosts. From a morphological perspective the Devescovinidae and Calonymphidae are considered more derived than the Monocercomonadidae and Trichomonadidae. Molecular trees inferred by distance, parsimony and likelihood techniques consistently show the Devescovinidae and Calonymphidae are the earliest diverging lineages within the Trichomonadida, however bootstrap values do not strongly support a particular branching order. In an analysis of all known 16S-like ribosomal RNA sequences, the Trichomonadida share most recent common ancestry with unidentified protists from the hindgut of the termite Reticulitermes flavipes. The position of two putative free-living trichomonads in the tree is indicative of derivation from symbionts rather than direct descent from some free-living ancestral trichomonad. 相似文献
425.