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RICO SPANGENBERG FRANK HÜNEFELD KATHARINA SCHNEEBERG ROLF GEORG BEUTEL 《Journal of Zoological Systematics and Evolutionary Research》2012,50(4):264-288
The male postabdomen and the internal parts of the male genital system of Bibio marci (Bibionomorpha) were examined and reconstructed 3‐dimensionally. Several features differ from the presumptive dipteran groundplan. The bases of the gonopods are fused with each other and with tergite IX. The penis is not tube‐shaped and only sclerotized on the ventral side. The vasa deferentia are S‐shaped, and two pairs of accessory glands are present. In contrast to these characteristics, the arrangement of the internal parts is probably close to the ancestral condition. With its specific shape, the penis is well suited for the transfer of a spermatophore. The dorsal sclerite of the copulatory organ probably represents the medially fused parameres. A cladistic analysis of 27 characters of the postabdomen yielded two most parsimonious trees, with the strict consensus as follows: Nannochoristidae (outgroup) + (Culicidae [Culicomorpha] + ((Nymphomyiidae + (Tipulidae + Trichoceridae)) + (Tabanidae [Brachycera] + (Bibionidae, Anisopodidae, Axymyiidae [Bibionomorpha])))). Potential synapomorphies of Bibionomorpha (including Axymyiidae) and Brachycera are the fusion of sternum IX with the gonocoxites, the fusion of the parameres forming the dorsal sclerite and the presence of an entire series of postabdominal muscles (M4, M20, M23, M26, M27, M31, M35 and M37). The results of the analysis are preliminary as it is based on a single‐character system with a limited taxon sampling. However, the main result – a clade Bibionomorpha + Brachycera – is fully compatible with current hypotheses on dipteran phylogeny. 相似文献
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J. A. GALARZA G. F. TURNER E. MACPHERSON J. CARRERAS‐CARBONELL C. RICO 《Molecular ecology resources》2007,7(2):230-232
Ten polymorphic dinucleotide microsatellite loci were isolated and characterized for the red mullet (Mullus barbatus). Allele variability was tested on both the red mullet and its congener the striped red mullet (Mullus surmuletus). Characterization of 30 individuals of both species from the western Mediterranean showed moderate to high allelic diversity ranging from two to 26 alleles per locus (mean 10.9). Three loci showed departures from Hardy–Weinberg proportions. No evidence of significant association between genotypes at pairs of loci was observed. These polymorphic loci could be suitable for population genetic assessments of both species. 相似文献
3.
CLARE J. HOPKINS NOEL O. I. COGAN MELANIE HAND ERICA JEWELL JATINDER KAUR XI LI GERALDINE A. C. LIM ALISON E. LING CHRISTOPHER LOVE HAYLEY MOUNTFORD MARIJA TODOROVIC MEGAN VARDY GERMAN C. SPANGENBERG DAVID EDWARDS JACQUELINE BATLEY 《Molecular ecology resources》2007,7(4):697-700
The availability of expressed sequence data derived from gene discovery programs enables mining for simple sequence repeats (SSR), providing useful genetic markers for crop improvement. These markers are inexpensive, require minimal labour to produce and can frequently be associated with functionally annotated genes. This study presents the development and characterization of 16 expressed sequence tags (EST)‐SSR markers from Brassica juncea and their cross‐amplification across Brassica species. Sixteen primer pairs were assessed for polymorphism in all genomes of the diploid and amphidiploid Brassica species. The markers show reliable amplification, considerable polymorphism and high transferability across species, demonstrating the utility of EST‐SSRs for genetic analysis of brassicas. 相似文献
4.
JACQUELINE BATLEY CLARE J. HOPKINS NOEL O. I. COGAN MELANIE HAND ERICA JEWELL JATINDER KAUR SUKHJIWAN KAUR XI LI ALISON E. LING CHRISTOPHER LOVE HAYLEY MOUNTFORD MARIJA TODOROVIC MEGAN VARDY MARZENA WALKIEWICZ GERMAN C. SPANGENBERG DAVID EDWARDS 《Molecular ecology resources》2007,7(5):886-889
The availability of expressed sequence data derived from gene discovery programs enables mining for simple sequence repeats (SSR), providing useful genetic markers for crop improvement. These markers are inexpensive, require minimal labour to produce and can frequently be associated with functionally annotated genes. This study presents the development and characterization of 24 expressed sequence tags (EST)‐SSR markers from Brassica napus and their cross‐amplification across Brassica species. The markers show reliable amplification, genome specificity and considerable polymorphism, demonstrating the utility of EST‐SSRs for genetic analysis of wild Brassica populations and commercial Brassica germplasm. 相似文献
5.
Assortative mating among rock-dwelling cichlid fishes supports high estimates of species richness from Lake Malawi 总被引:8,自引:1,他引:7
MADELEINE J. H. VAN OPPEN GEORGE F. TURNER CIRO RICO ROSANNA L. ROBINSON JAMES C. DEUTSCH MARTIN J. GENNER & GODFREY M. HEWITT 《Molecular ecology》1998,7(8):991-1001
It has been estimated that Lake Malawi, Africa, contains 500–650 endemic species of cichlid fishes, the largest number of vertebrate species endemic to any comparable sized area on the planet. As many of these putative species cannot be distinguished anatomically, these estimates of species richness depend to a great extent on the assumption that sympatrically occurring male colour morphs represent biological species. We have tested this assumption using a combination of behavioural observations of courtship and microsatellite DNA analysis for six putative species of the Pseudotropheus ( Tropheops ) complex and three of the Pseudotropheus ( Maylandia ) complex occurring sympatrically at Nkhata Bay. We were unable to demonstrate assortative courtship for the species pairs Pseudotropheus ( Maylandia ) zebra / P . 'gold zebra' or P. ( Tropheops ) 'band'/ P. ( T .) 'rust' because we were unable to distinguish between the females of these taxa. All other taxa showed clear assortative courtship, except for P. ( T .) 'deep', a deep-water species which was rarely observed. Fixation indices (θST for the infinite allele model, and R ST for the stepwise mutation model) calculated from six microsatellite DNA loci demonstrated significant deviations from panmixia in all pairwise comparisons of putative species, indicating little or no gene flow between populations. All taxa showed high levels of allelic diversity providing evidence that genetic bottlenecking may have been of limited importance in the speciation process. Assortative mating among taxa differing only in male colouration is supportive of theories that speciation in these fishes has been driven by sexual selection by female choice. 相似文献
6.
ENRIQUE RICO LUIS DELGADO ALBERTO HERRERO 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(4):701-708
We describe a species of Odontites, O. bolligeri E.Rico, L.Delgado & Herrero, endemic to the south‐eastern Iberian Peninsula and north Africa, from Morocco to Tunisia. This species belongs to the O. purpureus group and corresponds to the taxon that the monographer Markus Bolliger called O. squarrosus subsp. squarrosus. However, according to the International Code of Botanical Nomenclature (ICBN), this is an invalid name, and hence we propose a new name for these plants here. Drawings of the new species are also supplied. In addition, we compare and discuss the other species of the O. purpureus group, propose a key for them and include a karyological study of the two Iberian species of the group. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 701–708. 相似文献
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8.
LUIS DELGADO F'RANCISCA GALLEGO ENRIQUE RICO 《Botanical journal of the Linnean Society. Linnean Society of London》2000,132(3):263-280
Chromosome numbers in 80 populations belonging to 18 species of Potentilla L. subgen. Potentilla from the Iberian Peninsula and two of P. maura, a North African endemic taxon, have been counted. The basic number of chromosomes is always x = 7 and these chromosomes are small (between 1 and 2 μm). For three species, the number of chromosomes is reported for the first time and, for another six, this number has been established in Iberian representatives. Moreover, new ploidy levels have been obtained for P. hispanica and P. crantzii with regard to their entire distribution area, and in P. cinerea and P. neumanniana for the Iberian Peninsula. Some taxonomic, phylogenetic and phytogeographic comments are made for several species or groups of species from the West Mediterranean region. In 13 species only one ploidy level has been found, but six species have several ploidy levels. Seven ploidy levels occur in the investigated taxa. The frequency of each ploidy level represented within Iberian Potentilla is analysed and the data are compared with those available for taxa from the rest of the distribution area of the genus. 相似文献
9.
1. Most high mountain lakes were free of fish until humans stocked them. This provides the opportunity to study the extent to which predation constrains the thermal distribution of large macroinvertebrates, among lakes of a suitable temperature for them. 2. We analysed the distribution of aquatic beetles (Coleoptera, Dytisicidae, including the genera Agabus, Platambus, Hydroporus and Boreonectes) in a set of 82 lakes in the Pyrenees. Temperature was the most important variable explaining the overall distribution of dytiscids (out of 29 environmental variables considered). The presence of fish (i.e. salmonids) and macrophyte cover (plants provide refuge from predators) was also important. Indeed, either salmonids or macrophytes as single factors explained more of the variance in dytiscid distribution than temperature. 3. Further analysis showed that the presence of salmonids was particularly important for the medium‐sized dytiscid Agabus bipustulatus. This species is generally eurythermic, although in the Pyrenees it is found mainly in cold lakes. This is attributed to predation pressure from fish, since the latter are more likely to be present in warm lakes. As a consequence, salmonids increase fragmentation of A. bipustulatus with respect to populations occupying lowland habitats. 4. Predation can therefore constrain the distribution of species to a fraction of habitats that appear suitable based on simple thermal responses. As humans also facilitate the dispersal of non‐native fish, the consequent modification of distribution patterns in fresh waters could make it difficult to predict how distributions might change in relation to climate warming. 相似文献
10.
ANA P. MARTÍNEZ‐FALCÓN M. ÁNGELES MARCOS‐GARCÍA CECILIA DÍAZ‐CASTELAZO VICTOR RICO‐GRAY 《Ecological Entomology》2010,35(6):754-759
1. We analysed a cacti‐syrphid community focusing on the exploitation of decaying cacti resources by the flies, i.e. if exploitation exhibited a nested topology as a structural pattern, or whether it was temporally random. If availability of cactus resources was predictable during the rainy season, it would then be exploited by a more structured community, or as resource availability would be unpredictable during the dry season, we should expect it to be exploited by a random community. 2. We registered 12 Copestylum species (9 in dry and 11 in rainy season). Four cactus species were recorded per season, three were shared between seasons. 3. The community of Copestylum larvae in the rainy season was not randomly assembled but highly nested, revealing a highly structured pattern of resource use. It exhibited a random organization for the dry season. The high nestedness value obtained for the rainy season suggests that factors along with competition must play a major role in determining community structure. 4. Succession in the cacti‐syrphid community mediated by microorganisms involved in necrosis is an important factor structuring nested subsets. The studied networks were small, which may limit the power of the analysis, and strong conclusions could also be limited. 相似文献