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971.
The Larreoideae subfamily is the major representative of the family Zygophyllaceae in South America, where several of its members are common to dominant in arid regions of the Southern Cone. However, there are currently no phylogenetic analyses of the subfamily that may help to understand its origin and diversification. Additionally, there are taxonomic discrepancies around Bulnesia Gay (1845), one of its more important genera. Accordingly, we performed a phylogenetic analysis combining chloroplast (rbcL and trnL-F) and nuclear (ITS) DNA sequences. Bayesian and Parsimony analyses were performed to highlight the intergeneric relationships within Larreoideae. All genera with the exception of Bulnesia are monophyletic and we propose to redefine Bulnesia, dividing it in two genera. Furthermore, other taxonomic issues of the remaining genera are solved. This study represents the first approximation to clarify the phylogenetic relationships amongst all Larreoideae genera, producing a phylogenetic framework that can be used in future macro-ecological studies.  相似文献   
972.
The genus Asarum (Aristolochiaceae) encompasses approximately 120 species from five sections. Taxonomic controversies concerning the genus Asarum and/or its intrageneric classification remain unresolved. In particular, sect. Heterotropa accounts for a large percentage of the genus (80 of 120 species) and is well diverged in the Sino–Japanese Forest subkingdom. Reconstruction of Heterotropa phylogeny and estimation of its divergence times would provide significant insight into the process of species diversity in the Sino–Japanese floristic region. This study encompassed 106 operational taxonomic units (OTUs), and phylogenetic analyses were conducted based on internal transcribed spacer (ITS) and matK sequences. Although the matK sequences provided informative results solely for section Geotaenium, phylogenetic trees based on ITS regions yielded a clear result for several sections. Three sections, Asarum, Geotaenium and Asiasarum, were supported as robust monophyletic groups, whereas Heterotropa had low support. Sect. Hexastylis was revealed to be polyphyletic, suggesting taxonomic reconstruction would be needed. Sect. Heterotropa comprises two clades, which correspond to species distribution ranges: mainland China and the island arc from Taiwan to mainland Japan via the Ryukyu Islands. It is notable that the common ancestry of the latter clade in the eastern Asian islands was highly supported, suggesting that the present species diversity of Heterotropa was initially caused by allopatric range fragmentation in East Asia.  相似文献   
973.
The freshwater flatworm genus Schmidtea is endemic in the Western Palearctic region, where it is represented by only four species, thus contrasting with the high species diversity of the closely related genus Dugesia within Europe. Although containing an important model species in developmental and regeneration research, viz. Schmidtea mediterranea, no evolutionary studies on the genus Schmidtea have been undertaken. For the first time, we present a well‐resolved molecular phylogenetic tree of the four species of the genus, inferred on the basis of two molecular markers, and provide also the first detailed morphological account of Schmidtea nova. The phylogenetic tree generated corroborates an earlier speciation hypothesis based on karyological data and points to chromosomal rearrangements as the main drivers of speciation in this genus. The high genetic divergence between the four species, in combination with previous dating studies and their current geographic distribution, suggests that Schmidtea could have originated in Laurasia but lost most of its diversity during the Oligocene. Thus, its present distribution pattern may be the result of the expansion of three of its four relictual species over Europe, probably after the Pleistocene glaciations. Our detailed morphological study of S. nova revealed that it shows a number of remarkable features: interconnected testis follicles, parovaria, an ejaculatory duct exiting into the primary as well as the secondary seminal vesicle by means of a nipple, and the wall of the distal section of the ejaculatory duct being sclerotic or chitinized.  相似文献   
974.
I compared the type specimens of Drilus attenuatus Pic, 1914 and D. attenuatus var. subparallelus Pic, 1934 from Rhodes. Both taxa are redescribed and the latter is given the full species status based on the different external morphology and male genitalia. Altogether, four species are currently known from the island of Rhodes: Drilus attenuatus Pic, 1914, D. bleusei (Olivier, 1913), D. rufipes (Baudi di Selve, 1871), and D. subparallelus Pic, 1934 stat. rev. All species but D. rufipes are endemic to the island. An identification key to the males of Drilus species found in Rhodes is provided.  相似文献   
975.
Dyspessa peri sp. n. (Lepidoptera: Cossidae) is described from Sarobi in Central Afghanistan. The new species is closely related to D. tristis A. Bang-Haas, 1912, and is distinguished by peculiarities of the wing pattern and structure of the male genitalia.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:D58AAAC5-90F2-4D06-9DB2-C4D3CDE36265  相似文献   

976.
977.
Determining the boundaries between species and deciding when to describe new species are challenging practices that are particularly difficult in groups with high levels of geographic variation. The coast horned lizards (Phrynosoma blainvillii, Phrynosoma cerroense and P. coronatum) have an extensive geographic distribution spanning many distinctive ecological regions ranging from northern California to the Cape Region of Baja California, Mexico, and populations differ substantially with respect to external morphology across much of this range. The number of taxa recognized in the group has been reevaluated by herpetologists over 20 times during the last 180 years, and typically without the aid of explicit species delimitation methods, resulting in a turbulent taxonomy containing anywhere from one to seven taxa. In this study, we evaluate taxonomic trends through time by ranking 15 of these species delimitation models (SDMs) using coalescent analyses of nuclear loci and SNPs in a Bayesian model comparison framework. Species delimitation models containing more species were generally favoured by Bayesian model selection; however, several three‐species models outperformed some four‐ and five‐species SDMs, and the top‐ranked model, which contained five species, outperformed all SDMs containing six species. Model performance peaked in the 1950s based on marginal likelihoods estimated from nuclear loci and SNPs. Not surprisingly, SDMs based on genetic data outperformed morphological taxonomies when using genetic data alone to evaluate models. The de novo estimation of population structure favours a three‐population model that matches the currently recognized integrative taxonomy containing three species. We discuss why Bayesian model selection might favour models containing more species, and why recognizing more than three species might be warranted.  相似文献   
978.
979.
This study presents the carpological heterogeneity of Tragopogon pterodes, an endemic plant species from Balkan Peninsula. The goal of this paper was to determine the variability of morphological characters of achenes and assess the degree of their morphological differentiation relative to the position they occupy in the receptacle. Analysis included four different populations of T. pterodes and examination of 18 (8 qualitative and 10 quantitative) characters of achenes in total. Data analysis employed basic statistic, univariate (ANOVA, Tukey HSD) and multivariate (CDA, CA) analyses to check the level of heterocarpy in this species. The results indicate possible morphological differentiation of three groups of achenes (outer, median and inner achenes), depending of their position on the receptacle. The members of all three types were described, illustrated and compared. The variability of investigated carpological characters in this species is providing important information prior to their further taxonomic treatment.  相似文献   
980.
Stephanodictyon borneense was described by Dixon and later combined to Trichostomum by Zander. Until now, it had been considered endemic to Malaysia, known only from the type locality on Lobang, Kinabalu (Sabah state). Here, its taxonomic position is assessed based on morphological data. Our results suggest that the combination into the genus Chionoloma is required. Moreover, typification is performed and its distribution is increased. Stephanodictyon borneense is, therefore, newly reported for South and Central America (Colombia, Costa Rica, Haiti and Venezuela), for some Asiatic countries (India, Japan and Nepal) and for Papua New Guinea. Despite these new reports, S. borneense is a rare species with a highly scattered distribution.  相似文献   
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