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41.
Morphological variation among populations of Leporinus friderici (Bloch), an anostomid fish of widespread neotropical distribution, has been hypothesized but never conclusively demonstrated. We used multivariate procedures to examine patterns of morphometric variation among populations of L. friderici from three South American biogeographic regions: the Paraná-Paraguay River and Amazon River basins of Brazil, and the Marowijne River basin of Suriname. Samples from the southern Paraná-Paraguay basin are completely distinct from the northern Amazonian and Suriname regions in principal components analysis, primarily on the basis of body elongation and orbit differcnces. Samples from the two northern regions were separated in a size-free canonical variates analysis by differences in relative body depth. These results emphasize a need for further studies of neotropical fish species with similar distribution patterns. 相似文献
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Application of Coriphosphine Staining to the Study of the Macronuclear Anlage of Stylonychia mytilus
CONCEPIÓN FEDRIANI ANTONIO TORRES JULIO PÉREZSILVA 《The Journal of eukaryotic microbiology》1976,23(3):417-420
SYNOPSIS. Coriphosphine staining of Stylonychia mytilus exconjugants at different times after separation reveals some details of the developing macronucleus. Green fluorescence is seen in both bands and heterochromatic blocks of the polytene chromosomes. No red fluorescence was observed along these chromosomes. Fragments of the old macronucleus and the pycnotic micronuclei have red or orange fluorescence. Red fluorescence is characteristic also of nucleoli in the new macronucleus. 相似文献
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We perform phylogenetic analyses of the ‘polymorphic earless praying mantises’, a heterogeneous assemblage comprising c. 55% of mantodean diversity in the Neotropics. Bayesian and maximum‐likelihood were implemented on a DNA dataset of 9949 aligned nucleic acid characters comprising ten mitochondrial and nuclear genes. Our analyses largely resolved congruent relationships with high levels of support for higher‐level taxonomic groups, but revealed extensive inconsistencies between the resolved topology and morphology‐based classification systems. The polymorphic earless praying mantises, now granted superfamily status as the Acanthopoidea stat. n., comprises 8 families, 15 subfamilies and 18 tribes. Our newly revised organization required the following taxonomic changes: (i) Thespidae sensu n., including subfamilies Pseudopogonogastrinae subfam. n., Pseudomiopteryginae sensu n., Bantiinae subfam. n., Miobantiinae sensu n. and Thespinae sensu n. (tribes Musoniellini trib. n. and Thespini sensu n. ); (ii) Angelidae stat. n. et sensu n. ; (iii) Coptopterygidae stat. n. ; (iv) Liturgusidae sensu n. ; (v) Photinaidae stat. n., including Macromantinae stat. n., Cardiopterinae stat. n., Photiomantinae subfam. n. and Photinainae sensu n. (tribes Microphotinini trib. n., Orthoderellini stat. n. and Photinaini sensu n. ); (vi) Stenophyllidae stat. n. ; (vii) Acontistidae stat. n. ; and (viii) Acanthopidae sensu n. Our new system also resulted in the reassignment of various genera to new and existing higher‐level taxa, the exclusion of old world genera otherwise traditionally classified among the Thespidae, Liturgusidae and Angelidae, the confirmation of Stenophylla Westwood as member of this clade, and the revalidation of Paradiabantia Piza stat. r. We provide diagnoses for all suprageneric taxa using external morphological characters and male genitalia. A key to higher‐level groups is provided. We incorporate egg case structural variation as a novel approach for taxon delineation. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:29E37322‐30EB‐4F64‐80C9‐E2149B5B0195 . 相似文献
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A morphological and anatomical study of fruits and seeds often species ofVerbascumfrom south-west Spain has been made.The seeds showed considerable uniformity in shape, size, seed-coatornamentation and internal structure. Two groups of speciesare distinguished on the basis of indumentum of the capsules.The first group has branched hairs which do not appear in thesecond. Only one species,V. virgatummay be included in bothgroups. Other characters such as corolla size or stamen number,support separation of both groups and reaffirm the intermediateposition ofV. virgatum. A key to distinguish the taxa is provided.Copyright1997 Annals of Botany Company Pericarp; seed-coat; SEM; anatomy 相似文献
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MARCOS A. VANNIER-SANTOS JULIO A. URBINA REA MARTINY REA NEVES WANDERLEY DE SOUZA 《The Journal of eukaryotic microbiology》1995,42(4):337-346
ABSTRACT. The antiproliferative effects and ultrastructural alterations induced in vitro by two antifungal compounds, the azole ketoconazole and the allylamine terbinafine on Leishmania amazonensis are reported. Promastigotes treatment with ketoconazole and terbinafine induced growth arrest and cell lysis in 72 hours. Combination of the two agents produced additive effects on promastigote axenic growth and synergistic effects on intracellular amastigote proliferation. The amastigotes, either axenically grown or infecting murine macrophages, were about 100-fold more sensitive to the drugs. These compounds induced the appearance of large multivesicular bodies, especially after ketoconazole treatment, increased amount of lipid inclusions as well as numerous, polymorphic volutin granules, particularly in terbinafine-treated cells. Multivesicular bodies were observed in close apposition with organelles such as mitochondria, which also showed alterations in the distribution and appearance of cristae, and the formation of paracrystalline arrays within the matrix. Some cells presented large portions of cytoplasm wrapped by endoplasmic reticulum and many parasites also presented myelin-like endoplasmic reticulum profiles. Such alterations together with the strong acid phosphatase activity observed in the multivesicular bodies and volutin granules may indicate the existence of an unusual autophagic process in cells treated with ergosterol biosynthesis inhibitors. 相似文献