Table of Contents

01 March 2025, Volume 63 Issue 2

Cover illustration: In this study, Fujiwara et al. (pp. 187–204) recovered support for the hypothesis that lineage specific trends are a major contributor to the observed genomic disparity in land plants. This hypothesis was tested by comparing the phylogenetic history of genomic diversity by focusing on genome size and chromosome number in two major lineages of land plants, namely the sister lineage liverworts and mosses. The study confirmed the different contributions of mechanisms such as whole genome duplications, diploidization, and up/down of genome size in the evolution of these two bryophyte lineages despite the shared ancestry and the dominance of the gametophyte in their haplodiplontic life cycle. The image illustrates three archegoniophores with pseudoperianthes composed of petaloid lobes of the temperate East-Asian liverwort Asterella mussuriensis (Kashyap) Verd. Photograph by Rui-Liang Zhu. [Detail] ...

  

Research Article
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  A deep dive into bryophyte genome space reveals opposing evolutionary trends in the sister lineages, mosses and liverworts

  Tao Fujiwara, Hong‐Mei Liu, Rui‐Liang Zhu, Harald Schneider

  J Syst Evol. 2025, 63(2): 187-204.
  https://doi.org/10.1111/jse.13159

  Abstract  |  Full Text PDF  |  Save

  Among the lineages of the tree of life, land plants exhibit a remarkably high genomic disparity because of their distinct evolutionary trajectories in the phylogenetic history of their major lineages. The macroevolutionary pattern of genomic evolution has been mainly investigated to obtain insights into well-studied lineages such as angiosperms, but little attention has been given to many important lineages such as bryophytes. This study was designed to resolve this gap by comparing the genomic evolution trajectories of mosses and liverworts. Thus, a data set comprising chromosome number and genome size was compiled, including previously published and newly generated data that were used to trace the phylogenetic history of these two parameters among mosses and liverworts via ancestral state reconstruction and phylogenetic comparative analyses. Contrasting patterns of chromosome number and genome size evolutions were detected between the two sister lineages. Mosses accumulated high chromosome number disparity via repeated whole-genome duplications and descending dysploidy but maintained a small genome size. By contrast, the chromosome number of liverworts was highly conserved, and heterogeneous trends in genome size evolution were identified among major lineages. These contrasting patterns may be partly explained by the difference in genomic dynamics: Active dynamics enables genome downsizing and reorganization in mosses, whereas genome stability leads to the accumulation of large genomes in liverworts. The results of this study confirmed the distinct trends of genomic evolution in bryophytes.

  By examining the evolution of chromosome numbers and genome sizes within a large-scale phylogenetic framework, we explored the genomic landscape of bryophytes, specifically focusing on mosses and liverworts. Our key findings revealed contrasting patterns of chromosome number and genome size evolutions between the two sister lineages. Mosses accumulated high chromosome number disparity via repeated whole-genome duplications and descending dysploidy after whole-genome duplications (WGDs) but maintained a small genome size by genome down-sizing after WGDs. By contrast, the chromosome number of liverworts was highly conserved, and heterogeneous trends in genome size evolution were identified among major lineages. These contrasting patterns may be partly explained by the difference in genomic dynamics: Active dynamics enables genome downsizing and reorganization in moss, whereas genome stability leads to the accumulation of large genomes in liverworts.
Commentary
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  Escarpment evolution in Madagascar unveils a pathway to understanding island biodiversity

  Jun‐Nan Wan, Sheng‐Wei Wang, Si‐Chong Chen, Tao Wan

  J Syst Evol. 2025, 63(2): 205-207.
  https://doi.org/10.1111/jse.13162

  Abstract  |  Full Text PDF  |  Save

  A recent study on the flora diversity of the escarpment region in eastern Madagascar provided new insight into the mechanism of species diversification. Here we review this paper and emphasize the importance and novelty of the key findings and the methods. We suggest exploring the commonality of the findings in other regions with high biodiversity. We also recommend the examination of more relative case studies and wider application of the novel simulation method.
Research Article
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  Allopolyploidization events and immense paleogenome reshuffling underlying the diversification of plants and secondary metabolites in Oleaceae

  Jiaqi Wang, Yue Ding, Yinfeng Li, Xintong Gao, Xiangming Kong, Feng Long, Yishan Feng, Yan Zhang, Yu Li, Zijian Yu, Tianyu Lei, Li Wang, Xiu‐Qing Li, Jinpeng Wang

  J Syst Evol. 2025, 63(2): 208-228.
  https://doi.org/10.1111/jse.13116

  Abstract Full Text PDF  |  Save

  Oleaceae, a eudicot family with great species diversity, has attracted much attention from botanists because it contains many plants with important economic, medicinal, and ornamental values. However, the history of polyploidization and ancestral genome reshuffling of Oleaceae remains unclear. Here, we clarified an Oleaceae-common hexaploidization (OCH) event occurring at ~53–61 million years ago (Ma) common in all Oleaceae plants and an Oleaceae-recent tetraploidization (ORT) event occurring at ~18–21 Ma shared by the lineages of Syringa, Olea, Osmanthus, and Fraxinus. We found that high-frequency polyploidization events drove the frequency of gene loss in Oleaceae genomes and extended the size of regions containing adjacent gene loss, thereby promoting the degree of genome fragmentation. We revealed that biased fractionation between the OCH- and ORT-produced subgenomes is likely attributed to the origin of allopolyploidization in the OCH and ORT events. Significantly, through paleochromosome rearrangement comparisons, we proposed a "two-step" genome duplication model for OCH and determined the duplicated orders of OCH tripled genome. We reconstructed 11 protochromosomes of the most recent ancestral Oleaceae karyotype (AOK) and elucidated the trajectories of immense paleochromosome reorganization of Oleaceae species from ancestral eudicot karyotype. Notably, we tracked the diversification history of secondary metabolite synthesis genes in the Oleaceae and explored the effects of paleogenome evolution on specialized metabolite synthesis. Our findings provide new insights into the polyploidization and paleogenomic evolution of Oleaceae and have important scientific significance for understanding the genetic basis of species and secondary metabolic diversity in Oleaceae.

  In this study, we revealed the frequent allopolyploidization events and immense paleogenome reshuffling during the diversification of plants in Oleaceae. At the same time, we explored the effects of these ancient evolutionary events on the synthesis of specific secondary metabolites and environmental adaptability of extant plants from Oleaceae.
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  Phylogenetic diversity and interspecies competition shaped species diversity in adaptive radiated Ligustrum (Oleaceae)

  Yushuang Wang, Enze Li, Jiahui Sun, Zhixiang Zhang, Wenpan Dong

  J Syst Evol. 2025, 63(2): 229-244.
  https://doi.org/10.1111/jse.13117

  Abstract  |  Full Text PDF  |  Save

  Speciation events often occur with adaptive radiation. The factors that promote these adaptive radiating species diversity patterns have intrigued biologists for more than a century. In the present study, we used the adaptive radiated genus Ligustrum to evaluate the relative contributions of the environment, species interactions, phylogenetic diversity, and diversification rates in generating extant species diversity patterns. Using complete chloroplast genome data, we reconstructed the highly supported and dated backbone phylogenetic relationships of Ligustrum. Biogeographic results indicated that Ligustrum originated in Southwest China during the Oligocene and spread to suitable areas that were warm and humid via 18 dispersal events. For the overlapping ranges of species pairs, a smaller phylogenetic distance was detected in high species overlap than in low species overlap, which is consistent with no significant difference in niche among the different species. We found that the phylogenetic diversity and interspecies competition induced by insignificant niche divergence shaped the global pattern of Ligustrum diversity.

  We used the adaptive radiated genus Ligustrum as a model generated a path model to discover the relative contributions of the environment, interspecific correlation, phylogenetic diversity, and diversification rates in generating extant species diversity patterns. We used species overlap to indicate species correlations and illustrated interspecies competition effect on species diversity through the correlation between species overlap and environment variables, diversification rates, and phylogenetic diversity. Our results indicated phylogenetic diversity and interspecies competition induced by insignificant niche divergence shaped the global pattern of Ligustrum diversity.
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  Chromosome-level genome assembly of a rare karst-growing Rhododendron species provides insights into its evolution and environmental adaptation

  Sulin Wen, Xiaowei Cai, Kun Yang, Yi Hong, Fuhua Fan, Qian Wang, Bingxue Zhang, Qiandong Hou, Yuxing Leng, Guang Qiao, Xiaopeng Wen, Xiaohui Shen

  J Syst Evol. 2025, 63(2): 245-267.
  https://doi.org/10.1111/jse.13130

  Abstract  |  Full Text PDF  |  Save

  Rhododendron is a significant plant genus, with over 600 identified species in China. The subgenus Hymenanthes holds the largest number of Rhododendron germplasms and showcases strong environmental adaptability. However, there remains a lack of understanding regarding Rhododendron's evolution and environmental adaptations. Rhododendron bailiense Y.P.Ma, C.Q.Zhang & D.F.Chamb., an exceedingly rare species, thrives in the alkaline karst landforms of Guizhou, southwest China, different from the typical growing environment of other Rhododendron species. In this study, we present a chromosome-level genome assembly of R. bailiense, revealing a genome size of 923.3 Mb, a contig N50 of 24.5 Mb, and a total of 47 567 predicted genes. An evolutionary analysis indicated that R. bailiense diverged from its ancestors prior to the other subgenus Hymenanthes rhododendrons, with the expanded and contracted genes being notably enriched in “stress response” and “growth,” respectively. Rhododendron bailiense is predominantly found on limestone soil in the mountains of Guizhou, with only two wild populations known. The genome of R. bailiense contained a high copy number of ankyrin repeat (ANK) and Ca²⁺-ATPase (CAP) genes, primarily involved in Ca²⁺ transport, shedding light on how R. bailiense copes with karst high-calcium stress. In contrast, the structures of the ANKs displayed unique characteristics, while the CAPs showed conservatism. The R. bailiense genome provides new insights into the adaptation and evolutionary history of Rhododendron plants in karst environments, potentially offering valuable information for adaptive breeding and ecological enhancement in such challenging settings.

  Rhododendron bailiense is an extremely rare species that grows in the alkaline karst landscape of Guizhou, China, and stands out from the typical growing environment of other Rhododendron species. We present a chromosome-level genome assembly of R. bailiense, showing a genome size of 923.3 Mb, a scaffold N50 of 61.8 Mb, and a total of 47 567 predicted genes. The genome contains high copy numbers of ankyrin repeat (ANK) genes and Ca²⁺-ATPase (CAP) genes, which are mainly involved in Ca²⁺ transport, indicating how R. bailiense responds to karst high-calcium stress.
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  Areas of endemism of the orchids of Megamexico: Hotspots of biotic interactions with pollinators

  Brandon E. Gutiérrez–Rodríguez, Wesley Dáttilo, Fabricio Villalobos, Victoria Sosa

  J Syst Evol. 2025, 63(2): 268-281.
  https://doi.org/10.1111/jse.13119

  Abstract  |  Full Text PDF  |  Save

  Ecological interactions and evolutionary processes in areas of endemism remain little studied despite the fact that identifying the patterns of functional signatures in areas of endemism could reveal important information regarding community assembly and functioning. Here, we investigated whether areas of endemism of the orchids of Megamexico are hotspots of biotic interactions by comparing the orchid–pollinator interactions with those of adjacent areas. Patterns of functional signatures and phylogenetic signal were estimated, using pollination syndromes as a proxy for functional attributes. Phylogenetic signal was estimated by coding pollinator groups for every orchid recorded. Metrics of the interaction networks and the phylogenetic signal were compared with those obtained from adjacent areas. Our results indicate that areas of endemism show higher significant differences in the phylogenetic signal compared with adjacent areas. This can be explained by the many distantly related orchid lineages sharing attributes related to pollination. Network size and robustness differed statistically between the areas of endemism and the adjacent areas. The same configuration of modules in interaction networks was found in the areas of endemism; however, remarkably, the composition of species in large genera differed in these areas. Areas of endemism harbor more orchid lineages that closely interact with many groups of insects. The southerly areas of endemism in Chiapas and Central America are prominent, with the most significant phylogenetic signal and networks metrics. Results indicate that areas of endemism for the orchids of Megamexico represent hotspots of biotic interactions. Strategies for conservation must take this biotic interaction into account.

  To investigate whether areas of endemism of the orchids of Megamexico are hotspots of orchid–pollinator interactions, phylogenetic signal and interaction networks were determined and compared with adjacent areas. Size and robustness differed statistically between the areas of endemism and the adjacent areas, and phylogenetic signal was higher in areas of endemism. The most remarkable areas with the highest estimations were located southerly, in Chiapas, Mexico, and the north of Central America.
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  A phylogenomic approach to disentangling the evolution of the large and diverse daisy tribe Anthemideae (Asteraceae)

  David Criado‐Ruiz, Joan Vallès, Randall J. Bayer, Luis Palazzesi, Jaume Pellicer, Iván Pérez Lorenzo, Olivier Maurin, Elaine Françoso, Shyamali Roy, Ilia J. Leitch, Félix Forest, William J. Baker, Lisa Pokorny, Oriane Hidalgo, Gonzalo Nieto Feliner

  J Syst Evol. 2025, 63(2): 282-306.
  https://doi.org/10.1111/jse.13118

  Abstract Full Text PDF  |  Save

  The daisy tribe Anthemideae Cass. is one of the largest and most diverse tribes within Asteraceae. We analyzed a data set including 61 out of 111 Anthemideae genera, and all but four of the 19 currently recognized subtribes (Inulantherinae, Lapidophorinae, Lonadinae, and Vogtiinae) using a targeted high-throughput sequencing approach, the first focused on the tribe. We followed different phylogenomic approaches, using nuclear and plastid data, as well as additional analytical methods to estimate divergence times and diversification rates, to unravel the evolutionary history and classification of this tribe. Our results reinforce the phylogenetic backbone of the Anthemideae advanced in previous studies and further reveal the possible occurrence of ancient hybridization events, plastid capture, and/or incomplete lineage sorting (ILS), suggesting that complex evolutionary processes have played an important role in the evolution of this tribe. The results also support the merging of subtribe Physmasperminae into Athanasiinae and subtribe Matricariinae into Anthemidinae and clarify previously unresolved relationships. Furthermore, the study provides additional insights into the biogeographic patterns within the tribe by identifying three main groups: the Southern African Grade, the Asian Clade, and the circum-Mediterranean Clade. These groups partially coincide with previously identified ones. Overall, this research provides a more detailed understanding of the Anthemideae tribe and improves its classification. The study also emphasizes the importance of phylogenomic approaches for deciphering the evolutionary dynamics of large and diverse plant lineages.

  The daisy tribe (Anthemideae) is one of the most diverse within the Asteraceae family, which is the largest or second largest of all angiosperms. We analyzed the intricate evolutionary relationships within this tribe using a targeted high-throughput sequencing phylogenomic approach. Our results are broadly consistent with recent phylogenetic reconstructions of the tribe. However, they strengthen the phylogenetic backbone, refine biogeographic patterns, strongly support the merging of two of the currently accepted 19 subtribes into two others, and reveal the possible occurrence of ancient hybridization events.
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  Genomic differentiation and gene flow among Rattus species distributed in China and adjacent regions

  Ning Liu, Xin‐Lai Wu, Ruo‐Bing Zhang, Jin Wang, Qi‐Sen Yang, Ji‐Long Cheng, Zhi‐Xin Wen, Lin Xia, Alexei V. Abramov, De‐Yan Ge

  J Syst Evol. 2025, 63(2): 307-318.
  https://doi.org/10.1111/jse.13123

  Abstract Full Text PDF  |  Save

  The wild rats in the genus Rattus represent a group of murids characterized by rapid lineage diversification but limited morphological variation. Within this genus, there are several commensal species with high invasive capacity, such as Rattus norvegicus and R. rattus, which pose a global threat. Investigating the mechanisms behind their adaptive evolution is of utmost importance. In this study, we conducted morphological study and whole-genome sequencing on Rattus species distributed in China and adjacent regions to gain insights into morphological differentiation, as well as genomic divergence and gene flow using assembled mitochondrion genome and high-quality single nucleotide polymorphisms. Despite their morphological similarity and large overlap in morphospace, our analyses revealed significant genetic differentiation at the genomic level among Rattus species in China and adjacent regions. Specifically, intraspecific differentiation was observed in R. nitidus, R. norvegicus, and R. tanezumi, which may be related to habitat heterogeneity and geographic isolation. We hypothesize that as invasive rats expand their habitat, the diversification of ecological environments might lead to more environmentally adapted evolution and accelerated genetic differentiation. Furthermore, Dsuite and TreeMix analyses detected substantial introgression among different Rattus species, particularly evident between R. norvegicus and R. tanezumi. Strong gene flow signals suggest frequent hybridization events among these species, which may facilitate the acquisition of new environmental adaptability during their expansion into new territories. This study provides a preliminary analysis that serves as a foundation for a more comprehensive investigation into the rapid lineage diversification and adaptive introgression among Rattus species.

  We performed whole-genome sequencing on Rattus species distributed in China and adjacent regions to gain insights into genomic divergence and gene flow, utilizing assembled mitochondrial genomes and high-quality single nucleotide polymorphisms. Our analyses unveiled significant genetic differentiation at the genomic level among Rattus species in China and neighboring areas. Gene flow analyses detected substantial introgression signals among different Rattus species, with a particularly pronounced occurrence of gene flow between R. norvegicus and R. tanezumi. This study provides an initial analysis for a comprehensive exploration of rapid lineage diversification and adaptive introgression among Rattus species, serving as a foundation for further research.
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  Phylogenomic support for the allopolyploid origin of the northwest Iberian endemic orchid Dactylorhiza cantabrica with Hyb-Seq

  Eva Pardo Otero, Manuel Pimentel, Elvira Sahuquillo Balbuena, Rosalía Piñeiro

  J Syst Evol. 2025, 63(2): 319-330.
  https://doi.org/10.1111/jse.13131

  Abstract Full Text PDF  |  Save

  The orchid Dactylorhiza cantabrica H.A. Pedersen is a narrow endemic occurring in the western Cantabrian Mountains in northwest Spain. Previous allozyme and morphological studies suggest that it might have resulted from the hybridization of two widespread congeners: the triploid Dactylorhiza insularis and the diploid Dactylorhiza sambucina. However, this hypothesis has not been tested using multiple genetic markers necessary to analyze phylogenies in complex genera such as Dactylorhiza. In this study, the Hyb-Seq technique is applied together with the universal Angiosperms353 probe kit to sequence multiple plastid and low-copy nuclear genes. The phylogenetic relationships between the three species, estimated based on 269 and 266 nuclear genes under concatenation and coalescent-based approaches, respectively, revealed highly supported clades containing each putative parent, D. insularis and D. sambucina. The position of D. cantabrica was not well resolved, suggesting the existence of mixed inheritance, where different genes come from each parent. Phylogenetic networks, used for visualizing the conflict between nuclear gene trees, placed D. cantabrica between the two parents and revealed high levels of reticulation. In addition, nuclear genetic variation within and among species was explored with allele frequency-based tools further supporting the intermediate position of D. cantabrica and the hypothesis of a recent hybrid origin. Finally, 75 plastid genes revealed that D. insularis might have been the maternal donor. Altogether, our results point to the allopolyploid origin of D. cantabrica from D. insularis and D. sambucina, as well as to the clear genetic differentiation of the two parental species.

  Using phylogenomics and allele frequency-based approach based on multiple plastid and low-copy nuclear genes, we confirm the hybrid origin of Dactylorhiza cantabrica, an endemic allopolyploid orchid from north-western Iberia, as well as the clear genetic differentiation of the two parental species. In addition, plastid DNA might reveal that Dactylorhiza insularis was the maternal donor.
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  Reproductive and vegetative remains of an eucalypt (Myrtaceae) from the early Eocene of India

  Raman Patel, Ashif Ali, Rafael F. de Almeida, Rajendra S. Rana, Mahasin A. Khan

  J Syst Evol. 2025, 63(2): 331-344.
  https://doi.org/10.1111/jse.13078

  Abstract  |  Full Text PDF  |  Save

  Eucalypt fossils were widely reported from the Cenozoic deposits across the Southern Hemisphere (Australia, New Zealand, and Argentina). However, no attached reproductive and vegetative fossil remains of this myrtaceous clade have been discovered till now. We report and describe for the first time a fossil eucalypt twig with attached foliage, flower buds, and mature flowers from the early Eocene (~55–52 Ma) sediments (Palana Formation) of Rajasthan, western India. As both vegetative and reproductive organs are in organic connection, they clearly represent the same species. In addition, here we also introduce fossil materials of isolated leaves, flower buds, inflorescence, and flowers recovered from the same stratigraphic level. Our Eocene fossils and extant members of the eucalypt clade are related morphologically by means of robust, thick petiolate lanceolate-shaped leaves with intramarginal secondary veins; operculate flower buds consisting of imbricate petals with discernable margins; solitary inflorescence with three flowers per umbellaster, epigynous and bisexual flowers. Based upon combined characteristics of leaf, flower, and bud morphology, these fossils conform to the Eucalypt clade and are recognized as a new fossil genus and species: Hindeucalyptus eocenicus Patel, R.F. Almeida, Ali et Khan gen. nov. et sp. nov. We also compare it with extant and extinct eucalypts using morphological phylogeny and character mapping analyses. In addition, we briefly discuss its phytogeographic and paleoclimatic implications regarding the distribution and habitat of fossil and modern eucalypts.

  Herein, we report and describe for the first time the well-preserved fossilized eucalypt twig with attached foliage, flower buds, and free fuse inflorescence with flowers from the early Eocene (~55–52 Ma) sediments (Palana Formation) of Rajasthan, western India. Based upon combined characteristics of leaf, flower, and bud morphology, our Eocene fossil specimens are recognized as a new fossil genus and species Hindeucalyptus eocenicus sp. nov. We discuss its phytogeographic and paleoclimatic implications.
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  Phylogeography and local environmental adaptation in the differentiation of Leptocorisa sister species in East Asia

  Xue Dong, Xiuxiu Zhu, Zechen Tang, Wenbo Yi, Huaijun Xue, Zhen Ye, Chenguang Zheng, Wenjun Bu

  J Syst Evol. 2025, 63(2): 345-358.
  https://doi.org/10.1111/jse.13120

  Abstract  |  Full Text PDF  |  Save

  A full understanding of local adaptation at the genomic level will help to elucidate its role in the differentiation between closely related species. This study focused on rice seed bugs sister species (Leptocorisa chinensis and Leptocorisa oratoria), which are native to East Asia and are notorious pests targeting growing rice spikelets. East Asia is a region where diverse geology and fluctuating climate are known to have profound impacts on organisms. In this study, single nucleotide polymorphisms (SNPs) from double-digest restriction site-associated DNA sequencing and geographic distribution information were used to investigate phylogeography and assess the environmental contribution to genetic variation. We found clear genetic differentiation between sister species, but a lack of genetic structure within species because of their long-distance dispersal ability. The demographic model involved a scenario in which divergence in isolation (~0.6 Ma) was followed by secondary contact (~7 kya). The initial divergence may have been caused by the intensification of the East Asian monsoon during the Pleistocene climate oscillation. The historical demography indicated that the effective population size (N_e) showed an evident increase from 9 to 7 kya, which may be related to rice domestication and extensive human cultivation during the Holocene. We also detected a significant correlation between genetic and environmental distance, and the niche difference occupied between them. Temperature-related variables were ranked as the main factors for the difference, and 410 selective SNPs involved in adaptation were identified. The Nanling Mountains in southern China serve as a geographical boundary between them and act as an ecological barrier belt that promotes local environmental adaptation. Our study demonstrates that historical climate change and local adaptation by climate-imposed selection shape the phylogeographical patterns of sister species.

  We focused on the rice seed bugs sister species (Leptocorisa chinensis and Leptocorisa oratoria), notorious pests targeting growing rice spikelets native to East Asia. We combined double-digest restriction site-associated DNA sequencing and geographic distribution information to elucidate the phylogeographical pattern. There was significant isolation by environment; temperature-related variables were ranked as the main factors and selective single nucleotide polymorphisms involved in adaptation were identified. Both species, which are bounded by the Nanling Mountains in southern China, serve as an ecological barrier belt that promotes local environmental adaptation.
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  Evolution and mandibular sexual dimorphism in mid-Cretaceous scorpionflies (Insecta: Mecoptera: Meropeidae)

  Yanjie Zhang, Conrad C. Labandeira, Jiamiao Yu, Chungkun Shih, Dong Ren, Taiping Gao

  J Syst Evol. 2025, 63(2): 359-368.
  https://doi.org/10.1111/jse.13121

  Abstract  |  Full Text PDF  |  Save

  Based on several earwigfly specimens with well-preserved mouthparts of Meropeidae from mid-Cretaceous Burmese amber, a detailed, initial analysis was conducted of the structure of Mesozoic meropeids. Compared to the singularly flattened mandible of modern meropeids, the new specimens reveal that Mesozoic representatives had two distinct types of mandibles: blade-shaped and scoop-shaped. Current fossil evidence indicates that during the Mesozoic Era, Meropeidae displayed sexual dimorphism that was reflected in the structure of their mandibles. This structural difference may indicate that about 99 million years ago, meropeids had a more complex diet than extant confamilial taxa. Phylogenetic results suggest that Torvimerope gen. nov., along with Burmomerope, two extinct genera, form a clade and that are the sister taxon to crown-group Meropeidae. The new material offers new possibilities for inferring the feeding habits and mating behavior of early Meropeidae.

  Zhang et al. reported a trend in meropeids (Insecta, Mecoptera) toward shortening the rostrum, widening the clypeus, and reducing mandible size and teeth throughout their entire evolutionary process. These Cretaceous meropeids displayed sexual dimorphism, which was reflected in the structure of their mandibles, suggesting a more complex diet around 99 Ma.
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  A new stem-group mantispoid lineage (Insecta: Neuroptera) equipped with unique raptorial structures from the Middle Jurassic of China

  Jinglei Wang, Chaofan Shi, Xingyue Liu, Chungkun Shih, Dong Ren, Yongjie Wang

  J Syst Evol. 2025, 63(2): 369-378.
  https://doi.org/10.1111/jse.13125

  Abstract  |  Full Text PDF  |  Save

  During the Cretaceous period, the lacewing superfamily Mantispoidea, with an assemblage of species possessing raptorial forelegs, have undergone a rapid species radiation, characterized by abundant species richness and high morphological plasticity. Nevertheless, the morphology and early evolution of the specialized predatory organ around the time of its origin in raptorial Mantispoidea have been poorly documented due to the rarity of fossil evidence, especially for the pre-Cretaceous fossils. Herein, a new genus and new species, that is Archarhachiberotha longitarsa Wang, Ren et Wang gen. et sp. nov., was described from the Middle Jurassic Jiulongshan Formation of northeastern China. This new genus was characterized by the remarkable raptorial forelegs, that is, typically elongated coxa, relatively less-swollen femur and rudimentary small femoral spines, and well-developed tarsi. Considering the peculiar morphological combination and antiquity of the new genus, it was assigned to be a stem-group lineage of Mantispoidea. Also, the detailed analyses of morphology and biological functions of raptorial forelegs were made to conclude that the new genus evolved into an unknown but primitive raptorial type that was distinctly different from the extant morphological features and raptorial mechanisms. In addition, the evolutionary tendency of raptorial Mantispoidea herein summarized highlights morphological diversity and disparity between fossil and extant representatives, and provides a rare case to explore the entire evolutionary history of a specialized structure in one lineage.

  This image shows the unique raptorial forelegs of Archarhachiberotha longitarsa J. Wang, Ren & Y. Wang gen. & sp. nov., which is characterized by the typically elongated coxa, relatively less-swollen femur and rudimentary small femoral spines, and well-developed tarsi. Based on the detailed analyses of morphology and biological function of the raptorial forelegs, it is concluded Archarhachiberotha evolved into an unknown but primitive raptorial type that is distinctly different from the extant morphological features and raptorial mechanism.
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  Cenozoic Ampelopsis and Nekemias leaves (Vitaceae, Ampelopsideae) from Eurasia: Paleobiogeographic and paleoclimatic implications

  Aixa Tosal, Alba Vicente, Thomas Denk

  J Syst Evol. 2025, 63(2): 379-400.
  https://doi.org/10.1111/jse.13126

  Abstract Full Text PDF  |  Save

  We describe a new species of Ampelopsideae (Vitaceae), Nekemias mucronata sp. nov., from the Rupelian of Cervera (Spain) and revise another fossil species, Ampelopsis hibschii, originally described from Germany. Comparison with extant Ampelopsideae suggests that the North American species Nekemias arborea is most similar to Nekemias mucronata while the East Mediterranean Ampelopsis orientalis is the closest living relative of A. hibschii. Our review of fossil data indicates that, during the Eocene, four species of Ampelopsideae occurred in Eurasia, that is, N. mucronata in the Czech Republic, A. hibschii in Kazakhstan, and two fossil species in the Far East (Ampelopsis cercidifolia and Ampelopsis protoheterophylla). In the Oligocene, a new species, Ampelopsis schischkinii, appeared in Kazakhstan; meanwhile, N. mucronata spread eastwards and southwards, and A. hibschii mainly grew in Central Europe. In the late Oligocene, N. mucronata became a relict in the Iberian Peninsula and Nekemias might have persisted in Western Eurasia until the latest Miocene (“Ampelopsis” abkhasica). The last occurrence of A. hibschii was in the Middle Miocene in Bulgaria, probably a refuge of humid temperate taxa, along with Ampelopsis aff. cordata. Carpological remains suggest that this lineage persisted in Europe at least until the Pleistocene. Our data confirm previous notions of the North Atlantic and Bering land bridges being important dispersal routes for Ampelopsideae. However, such dispersion probably occurred during the Paleogene rather than the Neogene, as previously suggested. A single species of Ampelopsideae, A. orientalis, has survived in Western Eurasia, which appears to have been linked to a biome shift.

  Synthesis of the paleobiogeographical history of Ampelopsideae from Eurasia. Nekemias mucronata sp. nov. (A); Ampelopsis hibschii (B). The results indicate that both species were already present in Eurasia during the late Eocene and later, during Oligocene times, dispersed across Eurasia. The last population of N. mucronata thrived in Spain during the late Oligocene while A. hibschii persisted in Bulgaria until the Middle Miocene. These data confirm the North Atlantic and Bering land bridges as key dispersal routes for Ampelopsideae. Nevertheless, this dispersion presumably occurred during the Paleogene rather than the Neogene, as previously suggested.
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  Phylogenetic reconstruction of Didymocarpus and related genera in Gesneriaceae with establishment of two new genera

  Fang‐Pu Liu, Meng‐Qi Han, Peng‐Wei Li, Yin‐Zheng Wang

  J Syst Evol. 2025, 63(2): 401-415.
  https://doi.org/10.1111/jse.13124

  Abstract  |  Full Text PDF  |  Save

  The genus Didymocarpus Wall. is a core group of the subfamily Didymocarpoideae in Gesneriaceae with a complex taxonomic history. It has long been controversial to delimit Didymocarpus and its allies. We conducted phylogenetic reconstructions with high-density sampling of Didymocarpus and related genera by using four nuclear ribosomal DNAs (external transcribed spacer [ETS], internal transcribed spacer [ITS], 18S, 26S) and five chloroplast DNAs (atpB-rbcL, rpl16, rps16, trnH-psbA, and trnL-F). The results indicated that neither Didymocarpus nor Allocheilos are monophyletic. Based on molecular phylogenetic and morphological analyses, we delimitated the range of the Didymocarpus sensu stricto (s. str.) with two-section division, and established a new genus Palmatiboea for species originally placed in Didymocarpus. This genus is remarkably distinguished from Didymocarpus s. str. not only in molecular phylogeny and morphology but also in its specific geographic distribution, in that it is found only in Southeast China. In addition, we proposed a new monotypic genus Hequnia for Allocheilos guangxiensis that is completely isolated in phylogeny, consistent with a range of remarkably distinctive morphological characteristics. Our results clarify the systematics of Didymocarpus and the delimitation between it and related genera with establishment of two new genera.

  We conducted phylogenetic reconstructions with high-density sampling of Didymocarpus and related genera by using four nuclear ribosomal DNAs (ETS, ITS, 18S, and 26S) and five chloroplast DNAs (atpB-rbcL, rpl16, rps16, trnH-psbA, and trnL-F). The results indicate that neither Didymocarpus nor Allocheilos are monophyletic. Based on molecular phylogenetic and morphological analyses, we delimitate the range of the Didymocarpus sensu stricto (s. str.) with two-section division, and established a new genus Palmatiboea for species originally placed in Didymocarpus. This genus is remarkably distinguished from Didymocarpus s. str. not only in molecular phylogeny and morphology but also in its specific geographic distribution, found only in Southeast China. In addition, we also proposed a new monotypic genus Hequnia for Allocheilos guangxiensis that is completely isolated in phylogeny, consistent with a range of remarkably distinctive morphological characteristics. Our results clarify the systematics of Didymocarpus and the delimitation between it and related genera with establishment of two new genera.
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  Hybrid capture resolves the phylogeny of Tetradium (Rutaceae) and supports the inclusion of a species from Sulawesi

  Lee‐Ping Ang, Fabian Brambach, Salvatore Tomasello, Jun Wen, Marc S. Appelhans

  J Syst Evol. 2025, 63(2): 416-430.
  https://doi.org/10.1111/jse.13127

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  Tetradium, a genus within Rutaceae, comprises nine species found in Eastern and Southeastern Asia, distinguished by their opposite pinnate leaves and apocarpous or subapocarpous gynoecium with follicular fruits. While Hartley's 1981 monograph provided foundational insights, a comprehensive phylogenetic analysis of the genus is lacking. Using next-generation sequencing (NGS), this study aims to (i) establish an NGS molecular data set for Tetradium, (ii) elucidate interspecific relationships via the hybrid capture method and (iii) investigate the taxonomic status of Euodia meliifolia var. celebica. Our data set comprised 28 samples across nine species, sequenced using Illumina Miseq and Hiseq 4000 platforms, with downstream analyses conducted using the HybPhyloMaker pipeline and ASTRAL. Our findings revealed five main groups supported by both molecular and morphological data, highlighting changes in ovule number and seed functionality. Notably, the hybrid capture method proved invaluable for studying old herbarium specimens. Finally, taxonomic revisions were proposed, including the reclassification of E. meliifolia var. celebica as Tetradium celebicum, the fossil Euodia costata as Tetradium costatum, and the fossil Euodia lignata as Tetradium lignatum. An updated description for T. celebicum, supplemented by a specific identification key, is provided.

  The phylogeny of Tetradium containing nine species is presented. One of the nine species, Tetradium celebicum (Koord.) T.G.Hartley ex Brambach & Appelhans, which was previously named Euodia mellifolia var. celebica, is taxonomically and systematically revised.
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  The polyphasic approach reveals ten novel and one known Ascomycota taxa from terrestrial agarwood-producing trees

  Tian‐Ye Du, Saowaluck Tibpromma, Kevin D. Hyde, Ausana Mapook, Dong‐Qin Dai, Gui‐Qing Zhang, Steven L. Stephenson, Nakarin Suwannarach, Jaturong Kumla, Abdallah M. Elgorban, Kunhiraman C. Rajeshkumar, Sajeewa S. N. Maharachchikumbura, Qiang Li, Samantha C. Karunarathna

  J Syst Evol. 2025, 63(2): 431-468.
  https://doi.org/10.1111/jse.13128

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  Aquilaria (Thymelaeaceae), a tropical and subtropical plant, is one of the main genera that can produce agarwood. Aquilaria sinensis and Aquilaria yunnanensis are native Chinese tree species, and A. sinensis is China's main agarwood source. Agarwood is a nontimber forest product with high economic and medicinal value. First-grade agarwood is sold as much as $100 000 per kilogram. There has been little research on the saprobic fungi associated with Aquilaria, with only 11 records having been reported. In the present study, 10 terrestrial saprobic fungi associated with A. sinensis and A. yunnanensis were collected in China. Based on morphological and phylogenetic studies, these 10 collections are introduced herein as one new genus (Aquilariomyces), nine new species – Aquilariomyces aquilariae, Corynespora aquilariae, Melomastia maomingensis, Nigrograna aquilariae, Parathyridariella aquilariae, Peroneutypa maomingensis, Phaeoseptum aquilariae, Pseudothyridariella aquilariae, and Triangularia aquilariae, and one known species (Camarographium clematidis). Descriptions, illustrations of morphological characteristics, photo plates, phylogenetic trees, and the results of a pairwise homoplasy index test (PHI) test results are provided.

  A diversified saprophytic fungi population is a sign of a healthy ecosystem. Here, the authors studied saprobic fungi associated with two native Chinese agarwood-producing tree species (Aquilaria sinensis and A. yunnanensis) in Guangdong and Yunnan provinces, China. Based on morphological characteristics, multigene phylogenetic analyses, and pairwise homoplasy index (PHI) test, 10 collections are introduced herein as one new genus – Aquilariomyces, nine new species – Aquilariomyces aquilariae, Corynespora aquilariae, Melomastia maomingensis, Nigrograna aquilariae, Parathyridariella aquilariae, Peroneutypa maomingensis, Phaeoseptum aquilariae, Pseudothyridariella aquilariae, and Triangularia aquilariae, and one known species – Camarographium clematidis, belonging to different families of Ascomycota, namely, Corynesporascaceae, Diatrypaceae, Didymosphaeriaceae, Nigrogranaceae, Phaeoseptaceae, Pleurotremataceae, Podosporaceae, and Thyridariaceae.
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  Novel phylogenetic analysis of the Mesozoic common gymnosperm Xenoxylon Gothan reveals close affinity with extant Podocarpaceae (Coniferales)

  Aowei Xie, Shook Ling Low, Yongdong Wang, Ning Tian, Dieter Uhl

  J Syst Evol. 2025, 63(2): 469-478.
  https://doi.org/10.1111/jse.13132

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  Fossil wood is one of the crucial proxies for understanding terrestrial vegetation composition and development in the Earth's history. The gymnosperm wood taxon Xenoxylon Gothan is a significant member of the Mesozoic flora. To date, more than 20 species of Xenoxylon have been described. However, its botanical affinities have remained enigmatic ever since it was described, over a century ago. Here we perform a phylogenetic analysis of Xenoxylon to understand the systematic relationship with extant conifers. Data come from four nucleotide regions (trnL-F, trnK-matK, rbcL, psbA-trnH), xylological characters, and biomolecular composition of five extant conifer families; for Xenoxylon, no nucleotide data are available. Using maximum parsimony in Tree Analysis using New Technology, Xenoxylon appeared basal to Araucariaceae in the data set combining genes and xylological characters, whereas Xenoxylon is placed next to Podocarpaceae in the data set combining genes and biomolecular characters. To find a reliable systematic placement of Xenoxylon, a combined data set of genes, xylological and biomolecular characters is analyzed. Our results and interpretations indicate that Xenoxylon is closely related to Podocarpaceae. This first phylogenetic analysis of Xenoxylon fills the knowledge gap of the systematic relationship of this taxon and contributes to a better understanding of the evolution of extant Podocarpaceae.

  We perform a phylogenetic analysis of the Mesozoic common gymnosperm Xenoxylon to understand the systematic relationship with extant conifers. Data come from four nucleotide regions (trnL-F, trnK-matK, rbcL, psbA-trnH), xylological characters, and biomolecular composition of five extant conifer families and extinct Xenoxylon. Using maximum parsimony in Tree Analysis using New Technology, our results and interpretations indicate that Xenoxylon is closely related to the extant conifer family Podocarpaceae.
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  Gymnosperm collecting in China: Past, present, and future

  Dan Xie, Tian‐Xiang Chen, Hong Du, Hui Wu, Jin‐Hua Ran

  J Syst Evol. 2025, 63(2): 479-491.
  https://doi.org/10.1111/jse.13122

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  Assessing sampling biases caused by nonrandom specimen collecting is crucial in systematics, biogeography, and conservation. Nevertheless, research on the collecting biases of vascular plants in China remains limited. Here, we investigated the collecting status of gymnosperms in China using 48 673 herbarium specimens representing 180 Chinese gymnosperm species. The spatial and temporal patterns, collector and determiner biases, and phylogenetic and taxon biases were studied to comprehend the collecting bias of gymnosperms in China during 1900–2021. Meanwhile, we assessed the inventory completeness of gymnosperms to identify collecting hotspots and coldspots. The results showed that gymnosperms predominantly inhabit mountainous areas in China. The historical collecting of gymnosperms in China can be divided into two distinct stages with four peaks of collecting activities. The distribution of collected or identified specimens per individual displays significant skewness, and the collecting of gymnosperms has the issues of overcollecting or undersampling. Inventory completeness remains deficient, and collecting intensity is weak in both northern China and the range of 22°–25° N in the southern region (i.e., central Yunnan, southern Guangxi, and eastern Guangdong). Additionally, observation of the spatial distribution reveals both hotspots and coldspots scattered across mountain regions, lacking clustering. This study revealed a highly polarized collecting pattern for gymnosperms in China. Consequently, we recommend optimizing collecting measures, targeted specimen collecting, and continuous dynamic monitoring of gymnosperms in future collecting efforts. These recommendations hold relevance not only for gymnosperms in China but also for other land plants worldwide.

  The collecting of gymnosperms in China reveals a highly polarized pattern in terms of spatial and temporal distribution, as well as certain biases in phylogenetics and taxonomy. Generally, both collecting hotspots and coldspots scatter across mountain regions, lacking clustering. (i) time lapse in collecting history; (ii) frequency of specimen collecting; (iii) phylogenetic bias; and (iv) collecting hotspots and coldspots.