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1.
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The frequent transition from outcrossing to selfing in flowering plants is often accompanied by changes in multiple aspects of floral morphology, termed the “selfing syndrome.” While the repeated evolution of these changes suggests a role for natural selection, genetic drift may also be responsible. To determine whether selection or drift shaped different aspects of the pollination syndrome and mating system in the highly selfing morning glory Ipomoea lacunosa, we performed multivariate and univariate Qst‐Fst comparisons using a wide sample of populations of I. lacunosa and its mixed‐mating sister species Ipomoea cordatotriloba. The two species differ in early growth, floral display, inflorescence traits, corolla size, nectar, and pollen number. Our analyses support a role for natural selection driving trait divergence, specifically in corolla size and nectar traits, but not in early growth, display size, inflorescence length, or pollen traits. We also find evidence of selection for reduced herkogamy in I. lacunosa, consistent with selection driving both the transition in mating system and the correlated floral changes. Our research demonstrates that while some aspects of the selfing syndrome evolved in response to selection, others likely evolved due to drift or correlated selection, and the balance between these forces may vary across selfing species.  相似文献   

3.
Summary

In this publication, a subdivision of the genus Annenica O. Boettger, 1877 sensu Auct. is proposed. One result of our study is the recognition of the genus Sprattia O. Boettger, 1883 for most of the South Anatolian species of the former genus Armenica. The genus Astrogena Szekeres, 1970, which was synonymised by H. NORDSIECK (1975: 98) with Armenica is redefined and used as a subgenus of Armenica for some species. Extensive recent collections contain new species and subspecies of this genus, which are described here.  相似文献   

4.
A taxonomic revision of the genus Aneorhachis Kleine 1923 (Coleoptera: Brentidae) and a phylogenetic analysis of species belonging to this genus are carried out. The genus Ipsopisthius Kabakov 2001 is synonymised with Aneorhachis, and two new combinations are proposed: Aneorhachis hirta (Kabakov 2001), n. comb. and A. incerta (Kleine 1935), n. comb. Higonius nitens Goossens 2008 is synonymized with A. incerta. One new species is described from New Guinea, A. papuana n. sp. All the species are redescribed and type-specimens are illustrated; an identification key is proposed. A maximum parsimony analysis is provided on the base of 23 characters from adult morphology. This analysis confirms the monophyly of the genus and seems to show that Aneorhachis originated on continental Asia and then spread out eastward to colonize Pacific islands.  相似文献   

5.

The genus Novothymbris Evans is endemic to New Zealand, and is the only representative in this country of the subfamily Ledrinae. The genus and the known species are redescribed; dunensis (Myers) is synonymised with hinemoa (Myers), and hudsonica (Myers) with maorica (Myers). Eleven new species are described; three species‐groups are indicated. A key to species is given.  相似文献   

6.
Burmeistera, Centropogon, and Siphocampylus together comprise more than 500 species endemic to the Neotropics, Current knowledge of these genera is unsatisfactory, with much diversity yet to be described. Over the past seven years, one out of every 28 specimens received for identification has represented a new species, many characterized by unique or unusual character states. Siphocampylus smilax (Bolivia) is unique in the genus in its parallelodromous leaf venation and extra-floral nectaries. Centropogon dianae (Peru) cannot be accommodated in any recognized infrageneric taxon, and a new section, Centropogon sect. Niveopsis, is proposed for it. The flowers of C. steinii (Ecuador) are the smallest known in the genus, while C. connatilobatus (Venezuela) is the first species to combine arbusculiform pubescence and connate calyx lobes. Burmeistera venezuelensis is only the second species of the genus known to occur in Venezuela and the first to be endemic; similarly, Centropogon wilburii is only the third species of Centropogon known from Mexico and the first to be endemic to that country. Additional novelties are also described.  相似文献   

7.
The oriental species previously included in the rarely collected genus Nemotha Wood-Mason, 1884 (Mantodea: Iridopterygidae) are revised. N. coomani (Chopard, 1930) and N. mirabilis Beier, 1933 strongly differ from the type species N. metallica (Westwood, 1845) by family-level morphological features, but share a unique type of forefemoral armament with the genera Hapalopeza Stål, 1877 and Amantis Giglio-Tos, 1915, suggesting Nemotha is of a polyphyletic nature. The genus Tricondylomimus Chopard, 1930 is resurrected from synonymy to accommodate T. coomani, T. mirabilis n. comb. and the species which is newly described in this article, T. intermedius n. sp. The monotypic genus Pseudogousa Tinkham, 1937 and its species P. sinensis Tinkham, 1937 are synonymized with Tricondylomimus and T. mirabilis, respectively. The genus Tricondylomimus is placed in Iridopterygidae, while Nemotha is transferred to Hymenopodidae: Anaxarchini.  相似文献   

8.
Gene flow is thought to impede genetic divergence and speciation by homogenizing genomes. Recent theory and research suggest that sufficiently strong divergent selection can overpower gene flow, leading to loci that are highly differentiated compared to others. However, there are also alternative explanations for this pattern. Independent evidence that loci in highly differentiated regions are under divergent selection would allow these explanations to be distinguished, but such evidence is scarce. Here, we present multiple lines of evidence that many of the highly divergent SNPs in a pair of sister morning glory species, Ipomoea cordatotriloba and I. lacunosa, are the result of divergent selection in the face of gene flow. We analysed a SNP data set across the genome to assess the amount of gene flow, resistance to introgression and patterns of selection on loci resistant to introgression. We show that differentiation between the two species is much lower in sympatry than in allopatry, consistent with interspecific gene flow in sympatry. Gene flow appears to be substantially greater from I. lacunosa to I. cordatotriloba than in the reverse direction, resulting in sympatric and allopatric I. cordatotriloba being substantially more different than sympatric and allopatric I. lacunosa. Many SNPs highly differentiated in allopatry have experienced divergent selection, and, despite gene flow in sympatry, resist homogenization in sympatry. Finally, five out of eight floral and inflorescence characteristics measured exhibit asymmetric convergence in sympatry. Consistent with the pattern of gene flow, I. cordatotriloba traits become much more like those of I. lacunosa than the reverse. Our investigation reveals the complex interplay between selection and gene flow that can occur during the early stages of speciation.  相似文献   

9.
A new genus of Picramniaceae from tropical America, Nothotalisia, is described. Of the three species in the genus, N. piranii and N. cancellata, are new to science. The third, N. peruviana, was originally described as Talisia peruviana in the Sapindaceae. The genus and all three species are described, illustrated, and distinguished by means of a key.  相似文献   

10.

The catshark genus Holohalaelurus Fowler is currently represented by five species distributed off the southern and eastern parts of the African coast. Very few parasitological records exist for any of these five species, representing a significant knowledge gap. We report the first monogenean species from the bathydemersal species Holohalaelurus regani (Gilchrist): a new species of Microbothriidae Price, 1936, Leptomicrobothrium holohalaelure n. sp. from the dorsal skin surface, and a new species of Hexabothriidae Price, 1942 representing a new genus, Scyliorhinocotyle narvaezae n. gen., n. sp., from the gill lamellae. Both monogenean records represent the first for any member of the catshark genus Holohalaelurus. Previously we focused on the identification of monogenean taxa of emerging veterinary importance for public aquaria. We now begin a focused effort to document a generally unexplored monogenean biodiversity from diverse marine habitats off South Africa.

  相似文献   

11.
Three new species of the genus Aeschnosoma are briefly described and illustrated. A. pseudoforcipula n. sp. and A. heliophila n. sp., both from the Brazilian Central Plateau are respectively related to the two Amazonian species A. forcipula Hagen in Selys 1871, and A. auripennis Geijskes 1970. A. louissiriusi n. sp. from Northern Brazil is not closely related to any known species. Based on larval and adult derived characters, the genus Aeschnosoma appears closely related to the Australian genus Pentathemis Karsch 1890, and also to the Madagascan genus Libellulosoma Martin 1907. The clade Aeschnosomata nov. is erected to receive the three genera. Some putative plesiomorphies would place this clade sister group of the remaining Corduliidae s.str.  相似文献   

12.
《Journal of bryology》2013,35(3):161-164
Abstract

The genus Lobatiriccardia Furuki is reported as new to China, from the Dulong River valley, Gaoligong Shan range, Yunnan Province and this material is described as a new species endemic to China, Lobatiriccardia yunnanensis Furuki & D.G. Long, the fifth known species in the genus. The differences between the new species and the other members of the genus are enumerated, along with a key to all known species of Lobatiriccardia.  相似文献   

13.
Two new species of the family Myrmecolacidae, Myrmecolax comparilis n. sp. and Stichotrema sagax n. sp., are described from West Bengal, India. Myrmecolax comparilis is the third species of that genus described from India while Stichotrema sagax is the first record of that genus for this country.  相似文献   

14.
Two new species of the genus Apsiphortica are described from China: A. orthophallos n. sp. and A. sinuatipenis n. sp. Species delimitations are improved by integrating morphological and DNA barcoding information. The intra- and interspecific pairwise p-distances (proportional distance) are summarized for five Apsiphortica species from China. Furthermore, nucleotide sites with fixed status in the alignment of the COI sequences (639 nucleotide sites in length) are used as “pure” molecular diagnostic characters to delineate the five species. A key to all the Chinese species of the genus Apsiphortica is provided.  相似文献   

15.
A revision of certain generic boundaries within the tribe Malveae is made. A new genus,Sidasodes, is described with two species, one of which is new,Sidasodes colombiana.Akrosida is segregated as a new genus, based onBastardia macrophylla. The new realignment also recognizesTetrasida as a distinct genus, and describes as newTetrasida serrulata. New combinations includeSidasodes jamesonii (based onSida jamesonii),Akrosida macrophylla (based onBastardia macrophylla), andTetrasida chachapoyensis (based onSida chachapoyensis)  相似文献   

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The family Halictidae includes four subfamilies, Halictinae, Nomioidinae, Nomiinae and Rophitinae, apparently monophyletic. Systropha Illiger is the most diverse genus in Rophitinae (the Holartic genus Dufourea excluded). Several unique morphological, biogeographical and ecological features characterise the species within this taxon raising its interest for evolutionary studies. Now, to date there has been no extensive revision of the genus. The present work aims to alleviate this lack. In the first part, the authors propose an exhaustive catalogue, including the synonymy of the 26 described species. The last described species, Systropha heinzi Dubitzky 2004 syn. nov. is proposed as a junior synonym of S. kazakhstaniensis Patiny 2004, described one day earlier. The next parts of the study include a comprehensive key for the World species and the analysis of the species phylogeny based on 34 morphological characters. Converging with the conclusions of several former studies, this analysis points out the existence of 3 clades within the genus. These latter are described as 3 subgenera: S. (Systropha) Illiger 1806, S. (Systrophidia) Cockerell 1936 and S. (Austrosystropha) n. sg. Lastly, distribution and floral choices of taxa are specified.  相似文献   

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The western Palaearctic species of the genus Mesoleptus Gravenhorst 1829 are redescribed and keys are given for their identification. Also a key for the identification of the three stilpnine genera (Atractodes, Mesoleptus, and Stilpnus) is given and the biology of the genus is discussed shortly. The following species are described as new: Mesoleptus hispanicus n. sp., M. sawoniewiczi n. sp. and M. tunisiensis n. sp. The male of Mesoleptus tobiasi Jonaitis is described for the first time. New combinations is M. incessor (Haliday). New synonyms number 143 and 34 lectotypes are chosen.  相似文献   

20.
Summary. The little-known flower mantis genus Heliomantis Giglio-Tos 1915 (Hymenopodidae) distributed in South and South-Eastern Asia is revised. All species are redescribed. New data on the morphology, distribution and ecology are given, and all known specimens are listed. The lectotype of H. elegans (Navás 1904) is designated. Due to highly divergent morphology, H. latipennis Werner 1930 from Sarawak, Borneo, is transferred to Werneriana n. gen., leaving the genus Heliomantis with the only species, H. elegans (Navás, 1904).  相似文献   

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