Pub Date : 2024-01-18DOI: 10.1093/botlinnean/boad076
Tongxin Ye, Louis Ronse De Craene
Stipules are generally regarded as the outgrowths of the leaf base in angiosperms. Other interpretations see stipules as independent organs comparable to leaves. Stipules have been recognized as an important trait for plant taxonomy and identification, and there has been great progress in the understanding of their morphology, development, origin, function, and gene regulation over time. Therefore, this review will briefly summarize past research and aims to clarify the occurrence, location, and morphology of stipules in the families recognized by APG IV and reconstruct their ancestral states. Additionally, the developmental morphology of different types of stipule is presented through scanning electron microcopy observations and a survey of the existing literature. The difference between stipules and ligules is discussed in relation to the occurrence of postgenitally or congenitally fused ‘continuous’ stipules. A distinction is made between ‘true’ stipules and ‘pseudostipules’. The origin of stipules at the base of the leaf is explained from different perspectives. About one-third of the families are reported to have stipules, mostly concentrated in the Rosid clade with the highest level of diversity. On the basis of the ancestral state reconstructions, stipules may be absent in the ancestors of angiosperms, but are present in the ancestor of Rosids, with a pair appearing on both sides of the petiole base. The transition between paired and annular stipules is discussed, the latter arising postgenitally or congenitally. Several hypotheses are discussed to explain the abundance of stipules in the Rosid clade and their limited presence in the Asterid clade.
托叶通常被认为是被子植物叶基部的外生部分。其他解释则认为托叶是独立的器官,可与叶媲美。托叶已被认为是植物分类和鉴定的一个重要特征,随着时间的推移,人们对托叶的形态、发育、起源、功能和基因调控的认识也取得了很大进展。因此,本综述将简要总结过去的研究,旨在阐明托叶在 APG IV 确认的科中的发生、位置和形态,并重建其祖先状态。此外,还将通过扫描电子显微镜观察和对现有文献的调查,介绍不同类型托叶的发育形态。讨论了托叶和叶舌之间的区别,以及先天或后天融合的 "连续 "托叶的出现。对 "真 "托叶和 "假托叶 "进行了区分。从不同角度解释了叶基部托叶的起源。据报道,大约三分之一的科有托叶,主要集中在多样性水平最高的蔷薇科。根据祖先状态重建,被子植物的祖先可能没有托叶,但蔷薇科的祖先却有托叶,叶柄基部两侧各有一对。讨论了成对托叶和环状托叶之间的过渡,后者是后天或先天产生的。讨论了几种假说,以解释托叶在蔷薇科中的大量存在和在紫菀科中的有限存在。
{"title":"Stipules in angiosperms","authors":"Tongxin Ye, Louis Ronse De Craene","doi":"10.1093/botlinnean/boad076","DOIUrl":"https://doi.org/10.1093/botlinnean/boad076","url":null,"abstract":"Stipules are generally regarded as the outgrowths of the leaf base in angiosperms. Other interpretations see stipules as independent organs comparable to leaves. Stipules have been recognized as an important trait for plant taxonomy and identification, and there has been great progress in the understanding of their morphology, development, origin, function, and gene regulation over time. Therefore, this review will briefly summarize past research and aims to clarify the occurrence, location, and morphology of stipules in the families recognized by APG IV and reconstruct their ancestral states. Additionally, the developmental morphology of different types of stipule is presented through scanning electron microcopy observations and a survey of the existing literature. The difference between stipules and ligules is discussed in relation to the occurrence of postgenitally or congenitally fused ‘continuous’ stipules. A distinction is made between ‘true’ stipules and ‘pseudostipules’. The origin of stipules at the base of the leaf is explained from different perspectives. About one-third of the families are reported to have stipules, mostly concentrated in the Rosid clade with the highest level of diversity. On the basis of the ancestral state reconstructions, stipules may be absent in the ancestors of angiosperms, but are present in the ancestor of Rosids, with a pair appearing on both sides of the petiole base. The transition between paired and annular stipules is discussed, the latter arising postgenitally or congenitally. Several hypotheses are discussed to explain the abundance of stipules in the Rosid clade and their limited presence in the Asterid clade.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139500375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-11DOI: 10.1093/botlinnean/boad068
Felippe A Teixeira, Caian S Gerolamo, Amilcar W S Junior, Marcelo R Pace
Bark wings are projections commonly interpreted as plant protective structures against herbivory. Their location in stems has been typically thought to be random, something that here we dispute, using Piptadenia gonoacantha as a case study. We collected stem samples from several specimens in different developmental stages from natural populations in the Brazilian Atlantic rainforest. These stems were studied in detail under light microscopy to determine the formation of bark wings and their possible correlation with other anatomical features. Stems of P. gonoacantha are deeply lobed during primary growth, with each lobe containing a large vascular bundle, alternating with smaller vascular bundles in the interlobes. On top of these lobes, prickles develop, being composed of epidermal tissue and the cortex beneath. Some of the eight lobes merge and a phellogen is installed on top of them, which starts to produce a large sheath of phellem, which will become the conspicuous bark wings of Piptadenia. The phellogen switches on and off, leaving marks resembling growth rings. The bark wings in Piptadenia have very specific positioning, always in the front of five to eight major vascular bundles, indicating that bark wings appear always in very precise locations.
{"title":"Bark wings are related to the primary vascular system: the case of Piptadenia gonoacantha (Leguminosae)","authors":"Felippe A Teixeira, Caian S Gerolamo, Amilcar W S Junior, Marcelo R Pace","doi":"10.1093/botlinnean/boad068","DOIUrl":"https://doi.org/10.1093/botlinnean/boad068","url":null,"abstract":"Bark wings are projections commonly interpreted as plant protective structures against herbivory. Their location in stems has been typically thought to be random, something that here we dispute, using Piptadenia gonoacantha as a case study. We collected stem samples from several specimens in different developmental stages from natural populations in the Brazilian Atlantic rainforest. These stems were studied in detail under light microscopy to determine the formation of bark wings and their possible correlation with other anatomical features. Stems of P. gonoacantha are deeply lobed during primary growth, with each lobe containing a large vascular bundle, alternating with smaller vascular bundles in the interlobes. On top of these lobes, prickles develop, being composed of epidermal tissue and the cortex beneath. Some of the eight lobes merge and a phellogen is installed on top of them, which starts to produce a large sheath of phellem, which will become the conspicuous bark wings of Piptadenia. The phellogen switches on and off, leaving marks resembling growth rings. The bark wings in Piptadenia have very specific positioning, always in the front of five to eight major vascular bundles, indicating that bark wings appear always in very precise locations.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138575292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-07DOI: 10.1093/botlinnean/boad067
Ana Luisa Arantes Chaves, Ana Carolina Galindo da Costa, Isabel Cristina Machado, Rosemeri Morokawa, William Wayt Thomas, Suzana Maria Costa
Studies about reproductive aspects of angiosperms rarely refer to herbaceous and anemophilous groups. Cyperaceae are cosmopolitan and diverse in terms of sexuality, inflorescence architecture, and pollination modes, such as anemophily, entomophily, and ambophily. Therefore, the evolution of reproductive traits can clarify some questions about the reproductive biology of angiosperms, especially regarding the transitions between biotic and abiotic pollination. This study was designed to investigate the evolution of reproductive traits in Cyperaceae through comparative phylogenetic methods, such as reconstruction of ancestral states and evolutionary correlation. If spicoids in Mapanioideae are indeed inflorescences, the bisexual flower in Cyperaceae would be derived, a rare case in angiosperms. In Cyperoideae, a decrease in the number of flowers and an increase in stamen loss events were observed. This result contradicts the hypothesized increase in reproductive structures in anemophilous species, in which a greater amount of pollen is produced to compensate for the waste generated by wind. Only one correlation was found: between the number of inflorescence branches and the number of reproductive units per inflorescence. Finally, the analyses showed the great diversity of reproductive biology in Cyperaceae and made evident the need to expand the theoretical studies to refine the discovery of correlated traits.
{"title":"Inherit the wind: evolution of reproductive traits in Cyperaceae","authors":"Ana Luisa Arantes Chaves, Ana Carolina Galindo da Costa, Isabel Cristina Machado, Rosemeri Morokawa, William Wayt Thomas, Suzana Maria Costa","doi":"10.1093/botlinnean/boad067","DOIUrl":"https://doi.org/10.1093/botlinnean/boad067","url":null,"abstract":"Studies about reproductive aspects of angiosperms rarely refer to herbaceous and anemophilous groups. Cyperaceae are cosmopolitan and diverse in terms of sexuality, inflorescence architecture, and pollination modes, such as anemophily, entomophily, and ambophily. Therefore, the evolution of reproductive traits can clarify some questions about the reproductive biology of angiosperms, especially regarding the transitions between biotic and abiotic pollination. This study was designed to investigate the evolution of reproductive traits in Cyperaceae through comparative phylogenetic methods, such as reconstruction of ancestral states and evolutionary correlation. If spicoids in Mapanioideae are indeed inflorescences, the bisexual flower in Cyperaceae would be derived, a rare case in angiosperms. In Cyperoideae, a decrease in the number of flowers and an increase in stamen loss events were observed. This result contradicts the hypothesized increase in reproductive structures in anemophilous species, in which a greater amount of pollen is produced to compensate for the waste generated by wind. Only one correlation was found: between the number of inflorescence branches and the number of reproductive units per inflorescence. Finally, the analyses showed the great diversity of reproductive biology in Cyperaceae and made evident the need to expand the theoretical studies to refine the discovery of correlated traits.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138553240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-07DOI: 10.1093/botlinnean/boad069
Harvey K Orel, Todd G B McLay, Lydia K Guja, Marco F Duretto, Michael J Bayly
Zieria buxijugum, Z. formosa, and Z. parrisiae are three closely related, Critically Endangered species of questionable taxonomic validity that occur within six kilometres of each other on the south coast of New South Wales, Australia. We investigated genetic relationships and diversity of these species, along with two related but taxonomically distinct congeners, Z. granulata and Z. tuberculata, and a possible undescribed taxon, Z. aff. tuberculata. Double-digest restriction-site associated sequencing (ddRADseq) was used to generate anonymous genomic loci that were used for phylogenetic, network, and genetic structure analyses, and for estimating genetic diversity of the threatened species. Our results support the current taxonomic status of Z. buxijugum, Z. formosa, and Z. parrisiae, and suggest that Z. aff. tuberculata warrants recognition as a distinct species. We detected no evidence of inbreeding in the three Critically Endangered species, and found their genetic diversity to be similar to that of the more widespread species Z. granulata and Z. tuberculata. Comparison of plant material held in ex situ collections at the Australian National Botanic Gardens with wild plants highlighted several genotypes of the Critically Endangered species that are not represented in the ex situ collection, and we provide suggestions for the future inclusion of those unrepresented genotypes.
Zieria buxijugum、Z. formosa 和 Z. parrisiae 是三个密切相关的极危物种,其分类学有效性值得怀疑。我们研究了这些物种的遗传关系和多样性,以及两个相关但在分类学上不同的同系物 Z. granulata 和 Z. tuberculata,以及一个可能未被描述的类群 Z. aff.利用双位限制性位点相关测序(ddRADseq)生成匿名基因组位点,用于系统发育、网络和遗传结构分析,以及估计濒危物种的遗传多样性。我们的研究结果支持 Z. buxijugum、Z. formosa 和 Z. parrisiae 目前的分类地位,并认为 Z. aff. tuberculata 应被认定为一个独特的物种。我们在这三个极度濒危物种中没有发现近亲繁殖的证据,并发现它们的遗传多样性与更广泛分布的物种 Z. granulata 和 Z. tuberculata 相似。将澳大利亚国家植物园原地采集的植物材料与野生植物进行比较,发现有几种极度濒危物种的基因型在原地采集的植物材料中没有体现,我们为将来纳入这些未体现的基因型提出了建议。
{"title":"Genomic data inform taxonomy and conservation of Critically Endangered shrubs: a case study of Zieria (Rutaceae) species from eastern Australia","authors":"Harvey K Orel, Todd G B McLay, Lydia K Guja, Marco F Duretto, Michael J Bayly","doi":"10.1093/botlinnean/boad069","DOIUrl":"https://doi.org/10.1093/botlinnean/boad069","url":null,"abstract":"Zieria buxijugum, Z. formosa, and Z. parrisiae are three closely related, Critically Endangered species of questionable taxonomic validity that occur within six kilometres of each other on the south coast of New South Wales, Australia. We investigated genetic relationships and diversity of these species, along with two related but taxonomically distinct congeners, Z. granulata and Z. tuberculata, and a possible undescribed taxon, Z. aff. tuberculata. Double-digest restriction-site associated sequencing (ddRADseq) was used to generate anonymous genomic loci that were used for phylogenetic, network, and genetic structure analyses, and for estimating genetic diversity of the threatened species. Our results support the current taxonomic status of Z. buxijugum, Z. formosa, and Z. parrisiae, and suggest that Z. aff. tuberculata warrants recognition as a distinct species. We detected no evidence of inbreeding in the three Critically Endangered species, and found their genetic diversity to be similar to that of the more widespread species Z. granulata and Z. tuberculata. Comparison of plant material held in ex situ collections at the Australian National Botanic Gardens with wild plants highlighted several genotypes of the Critically Endangered species that are not represented in the ex situ collection, and we provide suggestions for the future inclusion of those unrepresented genotypes.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138553713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-29DOI: 10.1093/botlinnean/boad066
Micol Boschin, Peter Schönswetter, Božo Frajman
The Mediterranean Basin is a hotspot of animal and plant diversity. Contrary to the Balkan and Iberian Peninsulas that were subject of many phylogeographic studies in past decades, the Apennine Peninsula and, in particular, the diversification of its flora has been neglected in contemporary phylogenetic studies. The few available studies showed a complex pattern of north–south differentiation of genetic diversity in Italy, both among the Alps, the Apuan Alps, and the Apennines, as well as within the Apennines. Here, we explore phylogeographic patterns within recently described Euphorbia adriatica, distributed in the central and northern Apennine Peninsula, the southern margin of the Eastern Alps and the north-western Balkan Peninsula, and its relationship to the southern Italian E. japygica. Our integrative approach using nuclear ITS sequences, amplified fragment length polymorphisms, relative genome size estimation combined with chromosome counting, as well as multivariate morphometrics inferred a weak genetic differentiation that only partly corresponds to the morphological differentiation. Whereas all southern populations have hairy capsules characteristic for E. japygica, only those in south-eastern Italy (Puglia and Basilicata) are genetically divergent. There are, however, additional morphological characters that differentiate them from other populations. Our data are thus in favour of recognizing a single species, E. japygica, which includes E. adriatica that should be treated as a subspecies. We provide a revised taxonomic treatment for E. japygica, including the typification. Our study shows the necessity of further in-depth investigations of diversification of Italian biota.
{"title":"Genetic and morphological differentiation within Euphorbia japygica (Euphorbiaceae) suggests divergence of populations from the south-eastern Apennine Peninsula","authors":"Micol Boschin, Peter Schönswetter, Božo Frajman","doi":"10.1093/botlinnean/boad066","DOIUrl":"https://doi.org/10.1093/botlinnean/boad066","url":null,"abstract":"The Mediterranean Basin is a hotspot of animal and plant diversity. Contrary to the Balkan and Iberian Peninsulas that were subject of many phylogeographic studies in past decades, the Apennine Peninsula and, in particular, the diversification of its flora has been neglected in contemporary phylogenetic studies. The few available studies showed a complex pattern of north–south differentiation of genetic diversity in Italy, both among the Alps, the Apuan Alps, and the Apennines, as well as within the Apennines. Here, we explore phylogeographic patterns within recently described Euphorbia adriatica, distributed in the central and northern Apennine Peninsula, the southern margin of the Eastern Alps and the north-western Balkan Peninsula, and its relationship to the southern Italian E. japygica. Our integrative approach using nuclear ITS sequences, amplified fragment length polymorphisms, relative genome size estimation combined with chromosome counting, as well as multivariate morphometrics inferred a weak genetic differentiation that only partly corresponds to the morphological differentiation. Whereas all southern populations have hairy capsules characteristic for E. japygica, only those in south-eastern Italy (Puglia and Basilicata) are genetically divergent. There are, however, additional morphological characters that differentiate them from other populations. Our data are thus in favour of recognizing a single species, E. japygica, which includes E. adriatica that should be treated as a subspecies. We provide a revised taxonomic treatment for E. japygica, including the typification. Our study shows the necessity of further in-depth investigations of diversification of Italian biota.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138505107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-14DOI: 10.1093/botlinnean/boad046
Florian C Boucher, G Anthony Verboom, Laure Gallien, Allan G Ellis
Abstract Measuring the strength of different reproductive barriers across species pairs is key to reveal the mechanisms that have led to evolutionary radiations. Here we study a genus of miniature plants, Argyroderma, which comprises 11 species restricted to a single plain of the Southern African desert. We measure different reproductive barriers to understand how species boundaries are maintained in this genus. Our results show that reproductive isolation is almost complete between all species pairs and relies on three pre-mating barriers: geographic isolation operating at spatial scales of c. 10 km, phenological isolation in flowering time, and habitat isolation operating at spatial scales of just a few metres, which is thought to be due to contrasting edaphic preferences between species. In comparison, post-mating isolation arising before seed formation is weak and does not restrict gene flow much between species. Interestingly, the high levels of both geographic and habitat isolation that we have measured between Argyroderma species might be due to their miniature size, which leads to restricted gene flow across space and to adaptation to spatially restricted micro-habitats.
{"title":"Multiple reproductive barriers maintain species boundaries in stone plants of the genus <i>Argyroderma</i>","authors":"Florian C Boucher, G Anthony Verboom, Laure Gallien, Allan G Ellis","doi":"10.1093/botlinnean/boad046","DOIUrl":"https://doi.org/10.1093/botlinnean/boad046","url":null,"abstract":"Abstract Measuring the strength of different reproductive barriers across species pairs is key to reveal the mechanisms that have led to evolutionary radiations. Here we study a genus of miniature plants, Argyroderma, which comprises 11 species restricted to a single plain of the Southern African desert. We measure different reproductive barriers to understand how species boundaries are maintained in this genus. Our results show that reproductive isolation is almost complete between all species pairs and relies on three pre-mating barriers: geographic isolation operating at spatial scales of c. 10 km, phenological isolation in flowering time, and habitat isolation operating at spatial scales of just a few metres, which is thought to be due to contrasting edaphic preferences between species. In comparison, post-mating isolation arising before seed formation is weak and does not restrict gene flow much between species. Interestingly, the high levels of both geographic and habitat isolation that we have measured between Argyroderma species might be due to their miniature size, which leads to restricted gene flow across space and to adaptation to spatially restricted micro-habitats.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134991202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-08DOI: 10.1093/botlinnean/boad064
Ning Li, Zhen Wang, Qi Deng, Ting Wang, Ying-Juan Su
Abstract Habitat fragmentation can facilitate local adaptation of species to heterogeneous environments and affect population demographic history. To understand the factors influencing evolutionary dynamics, such as climatic fluctuations and complex geomorphological features, we used 18 chloroplast microsatellites, 15 nuclear microsatellites, three chloroplast fragments, and two nuclear regions to explore the genetic structure and phylogeographical history of Pseudotaxus chienii. Furthermore, its current and past distributions were constructed based on ecological niche modelling. Moderate to high levels of genetic diversity were found at the species level. Precipitation was a decisive factor influencing the genetic structure of P. chienii. In addition, local adaptation to heterogeneous environments also contributed to maintain the fragmented distribution. Finally, incomplete lineage sorting led to the cyto-nuclear discordance. Overall, we show that pre-Quaternary and Quaternary climatic fluctuations and restricted gene flow exerted significant effects on the formation and maintenance of the fragmented distribution of P. chienii. The study provides new insights into the evolutionary history of plants in subtropical China.
{"title":"Effects of climatic fluctuations on the fragmented distribution pattern of a Tertiary relict plant, <i>Pseudotaxus chienii</i> (Taxaceae), in subtropical China","authors":"Ning Li, Zhen Wang, Qi Deng, Ting Wang, Ying-Juan Su","doi":"10.1093/botlinnean/boad064","DOIUrl":"https://doi.org/10.1093/botlinnean/boad064","url":null,"abstract":"Abstract Habitat fragmentation can facilitate local adaptation of species to heterogeneous environments and affect population demographic history. To understand the factors influencing evolutionary dynamics, such as climatic fluctuations and complex geomorphological features, we used 18 chloroplast microsatellites, 15 nuclear microsatellites, three chloroplast fragments, and two nuclear regions to explore the genetic structure and phylogeographical history of Pseudotaxus chienii. Furthermore, its current and past distributions were constructed based on ecological niche modelling. Moderate to high levels of genetic diversity were found at the species level. Precipitation was a decisive factor influencing the genetic structure of P. chienii. In addition, local adaptation to heterogeneous environments also contributed to maintain the fragmented distribution. Finally, incomplete lineage sorting led to the cyto-nuclear discordance. Overall, we show that pre-Quaternary and Quaternary climatic fluctuations and restricted gene flow exerted significant effects on the formation and maintenance of the fragmented distribution of P. chienii. The study provides new insights into the evolutionary history of plants in subtropical China.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135430312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-08DOI: 10.1093/botlinnean/boad036
Shu-Han Li, Zheng-Yu Zuo, Cheng-Wei Chen, Van The Pham, Hong Truong Luu, Shi-Yong Dong
Abstract In Indochina the species diversity of Cyatheaceae remains insufficiently known. Here we demonstrate the scaly tree fern Gymnosphaera salletii in Vietnam to be an assemblage of three distinct species based on molecular and morphological data, and report for the first time the occurrence of foliar nectaries in Gymnosphaera. The true G. salletii is morphologically unique based on the protuberant glands present on the petiole. Gymnosphaera phankelocii sp. nov. and Gymnosphaeravietnamensis sp. nov. are recognized as new species; G. phankelocii is characterized by its distant two-rowed sori and G. vietnamensis by the sub-tripinnate fronds. Our phylogenetic analyses indicated that G. phankelocii is a relatively isolated species, while G. vietnamensis is a member of the G. salletii clade along with G. austroyunnanensis, G. salletii, and G. saxicola. The two new species and members of the G. salletii clade are all local endemics, and provide good examples to understand the frequent local endemics and their evolution in scaly tree ferns. Eleven species of Gymnosphaera are now known from Indochina; we provide a diagnostic key to these species.
{"title":"Three out of one: revising the species delimitation of the tree fern <i>Gymnosphaera salletii</i> (Cyatheaceae), with particular reference to the foliar nectary","authors":"Shu-Han Li, Zheng-Yu Zuo, Cheng-Wei Chen, Van The Pham, Hong Truong Luu, Shi-Yong Dong","doi":"10.1093/botlinnean/boad036","DOIUrl":"https://doi.org/10.1093/botlinnean/boad036","url":null,"abstract":"Abstract In Indochina the species diversity of Cyatheaceae remains insufficiently known. Here we demonstrate the scaly tree fern Gymnosphaera salletii in Vietnam to be an assemblage of three distinct species based on molecular and morphological data, and report for the first time the occurrence of foliar nectaries in Gymnosphaera. The true G. salletii is morphologically unique based on the protuberant glands present on the petiole. Gymnosphaera phankelocii sp. nov. and Gymnosphaeravietnamensis sp. nov. are recognized as new species; G. phankelocii is characterized by its distant two-rowed sori and G. vietnamensis by the sub-tripinnate fronds. Our phylogenetic analyses indicated that G. phankelocii is a relatively isolated species, while G. vietnamensis is a member of the G. salletii clade along with G. austroyunnanensis, G. salletii, and G. saxicola. The two new species and members of the G. salletii clade are all local endemics, and provide good examples to understand the frequent local endemics and their evolution in scaly tree ferns. Eleven species of Gymnosphaera are now known from Indochina; we provide a diagnostic key to these species.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135430462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.1093/botlinnean/boad057
Fernanda Hurbath, Bárbara S S Leal, Inês Cordeiro, Cleber J N Chaves, Clarisse Palma-Silva
Abstract The largest continuous patch of Seasonally Dry Tropical Forests (SDTF) is the Caatinga Biome in north-eastern Brazil, which has the greatest biodiversity and highest degree of endemism compared to any other SDTF patch of South America. Our aim was to conduct a phylogeographic study with Euphorbia phosphorea to understand the evolutionary history of this species endemic to the Caatinga Biome. We studied genetic diversity and structure, demographic dynamics, as well as intraspecific phylogenetic relationships, based on plastidial and nuclear DNA. In addition, we conducted species distribution modelling (SDM) to infer connectivity since the Last Interglacial. Our results recovered a stronger genetic structure for plastidial than for nuclear genome, which probably result from distinct species capability to seed and pollen dispersal, and low levels of genetic diversity within populations. Although SDM results suggest higher connectivity during Last Maximum Glacial, demographic analyses detected no signs of demographic expansion in this period. In agreement with previous studies with rock specialists, our data reveal remarkable among-population differentiation and low within-population genetic diversity, which make populations more prone to drift effects. Furthermore, our results shed light on the importance of early Pleistocene events in the diversification of lineages within the Caatinga Biome, although further comparative work is required.
{"title":"Phylogeographic analysis reveals early Pleistocene divergence and strong genetic structure in <i>Euphorbia phosphorea</i> (Euphorbiaceae), an endemic species to the semi-arid Caatinga Biome","authors":"Fernanda Hurbath, Bárbara S S Leal, Inês Cordeiro, Cleber J N Chaves, Clarisse Palma-Silva","doi":"10.1093/botlinnean/boad057","DOIUrl":"https://doi.org/10.1093/botlinnean/boad057","url":null,"abstract":"Abstract The largest continuous patch of Seasonally Dry Tropical Forests (SDTF) is the Caatinga Biome in north-eastern Brazil, which has the greatest biodiversity and highest degree of endemism compared to any other SDTF patch of South America. Our aim was to conduct a phylogeographic study with Euphorbia phosphorea to understand the evolutionary history of this species endemic to the Caatinga Biome. We studied genetic diversity and structure, demographic dynamics, as well as intraspecific phylogenetic relationships, based on plastidial and nuclear DNA. In addition, we conducted species distribution modelling (SDM) to infer connectivity since the Last Interglacial. Our results recovered a stronger genetic structure for plastidial than for nuclear genome, which probably result from distinct species capability to seed and pollen dispersal, and low levels of genetic diversity within populations. Although SDM results suggest higher connectivity during Last Maximum Glacial, demographic analyses detected no signs of demographic expansion in this period. In agreement with previous studies with rock specialists, our data reveal remarkable among-population differentiation and low within-population genetic diversity, which make populations more prone to drift effects. Furthermore, our results shed light on the importance of early Pleistocene events in the diversification of lineages within the Caatinga Biome, although further comparative work is required.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135723655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The species Peucedanum ledebourielloides, a medicinally important herb, has previously been placed in Peucedanum s.l. based on dorsally compressed mericarps with slightly prominent dorsal ribs and narrowly winged lateral ribs. However, this genus has now been re-delimited in a narrow sense, namely Peucedanum s.s., further recognized by ternate leaves and glabrous plants, so that the taxonomic position of P. ledebourielloides is unknown. To investigate the taxonomic position of this species, we sequenced and assembled the complete plastomes for two samples of P. ledebourielloides. Phylogenetic analyses based on 79 protein-coding genes showed that the samples of P. ledebourielloides formed a separate clade and were distant from Peucedanum morisonii, a representative member of Peucedanum s.s., implying that P. ledebourielloides cannot not be placed in Peucedanum s.s. Additionally, plastome comparisons and chromosome studies indicated the clear specificity of P. ledebourielloides. In particular, pinnate leaves and dorsally compressed mericarps densely covered with forked scabrous bristles, slightly prominent dorsal ribs, narrowly winged lateral ribs, and one vitta in each furrow and two vittae on the commissure clearly distinguished P. ledebourielloides from Peucedanum s.s. and other genera of Apiaceae. Hence, a new genus, Pseudopeucedanum gen. nov., was established to accommodate this species. Our results improve the taxonomy of the family Apiaceae and provide guidance for the taxonomic revision of other taxa that are difficult to place systematically.
{"title":"Plastid phylogenomics provide evidence to accept a new genus <i>Pseudopeucedanum</i> (Apiaceae) separated from <i>Peucedanum s.l.</i>","authors":"Chang-Kun Liu, Jiao-Jiao Deng, Bo-Ni Song, Huan-Huan Qin, Song-Dong Zhou, Xing-Jin He","doi":"10.1093/botlinnean/boad062","DOIUrl":"https://doi.org/10.1093/botlinnean/boad062","url":null,"abstract":"Abstract The species Peucedanum ledebourielloides, a medicinally important herb, has previously been placed in Peucedanum s.l. based on dorsally compressed mericarps with slightly prominent dorsal ribs and narrowly winged lateral ribs. However, this genus has now been re-delimited in a narrow sense, namely Peucedanum s.s., further recognized by ternate leaves and glabrous plants, so that the taxonomic position of P. ledebourielloides is unknown. To investigate the taxonomic position of this species, we sequenced and assembled the complete plastomes for two samples of P. ledebourielloides. Phylogenetic analyses based on 79 protein-coding genes showed that the samples of P. ledebourielloides formed a separate clade and were distant from Peucedanum morisonii, a representative member of Peucedanum s.s., implying that P. ledebourielloides cannot not be placed in Peucedanum s.s. Additionally, plastome comparisons and chromosome studies indicated the clear specificity of P. ledebourielloides. In particular, pinnate leaves and dorsally compressed mericarps densely covered with forked scabrous bristles, slightly prominent dorsal ribs, narrowly winged lateral ribs, and one vitta in each furrow and two vittae on the commissure clearly distinguished P. ledebourielloides from Peucedanum s.s. and other genera of Apiaceae. Hence, a new genus, Pseudopeucedanum gen. nov., was established to accommodate this species. Our results improve the taxonomy of the family Apiaceae and provide guidance for the taxonomic revision of other taxa that are difficult to place systematically.","PeriodicalId":9178,"journal":{"name":"Botanical Journal of the Linnean Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135774960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}