Ya Li, Carole T. Gee, Zhen-Zhen Tan, Yan-Bin Zhu, Tie-Mei Yi, Cheng-Sen Li
{"title":"华北河北省下中新世的铁杉新化石物种--Tsuga weichangensis sp.","authors":"Ya Li, Carole T. Gee, Zhen-Zhen Tan, Yan-Bin Zhu, Tie-Mei Yi, Cheng-Sen Li","doi":"10.1111/jse.12952","DOIUrl":null,"url":null,"abstract":"<p><i>Tsuga</i> (hemlock) is a small genus of 10 extant species in the Pinaceae, with a disjunct distribution in East Asia and eastern and western North America. Reliable species-level identification of <i>Tsuga</i> fossils depends on the discovery of seed cones with intact bracts, but such cones are rare in the fossil record. Here we describe a new fossil species of hemlock as <i>T. weichangensis</i> sp. nov. based on exquisitely preserved seed cones with nearly complete bracts from the Lower Miocene of Weichang, Hebei Province, North China. This fossil species displays a mosaic of characters between <i>Tsuga</i> and <i>Nothotsuga</i>. The well-developed and slightly exserted bract scales of <i>T</i>. <i>weichangensis</i> are reminiscent of <i>Nothotsuga</i>, but other characters, such as nonleaved peduncles and tongue-shaped bract scales, in addition to monosaccate pollen found at the same fossil locality, suggest an affinity closer to <i>Tsuga</i>. Cladistic analysis based on 15 morphological characters and a molecular backbone constraint supports the assignment of these fossil cones to <i>Tsuga</i> rather than <i>Nothotsuga</i>, and places the fossil species of <i>T</i>. <i>weichangensis</i> in an unresolved polytomy within the genus <i>Tsuga</i>. The occurrence of <i>Tsuga</i> seed cone fossils indicate the paleoclimate in the Miocene of Weichang was warmer and more humid than today's climate, which is consistent with the paleoclimate reconstructed by paleopalynology.</p>","PeriodicalId":17087,"journal":{"name":"Journal of Systematics and Evolution","volume":null,"pages":null},"PeriodicalIF":3.7000,"publicationDate":"2023-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Exceptionally well-preserved seed cones of a new fossil species of hemlock, Tsuga weichangensis sp. nov. (Pinaceae), from the Lower Miocene of Hebei Province, North China\",\"authors\":\"Ya Li, Carole T. Gee, Zhen-Zhen Tan, Yan-Bin Zhu, Tie-Mei Yi, Cheng-Sen Li\",\"doi\":\"10.1111/jse.12952\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><i>Tsuga</i> (hemlock) is a small genus of 10 extant species in the Pinaceae, with a disjunct distribution in East Asia and eastern and western North America. Reliable species-level identification of <i>Tsuga</i> fossils depends on the discovery of seed cones with intact bracts, but such cones are rare in the fossil record. Here we describe a new fossil species of hemlock as <i>T. weichangensis</i> sp. nov. based on exquisitely preserved seed cones with nearly complete bracts from the Lower Miocene of Weichang, Hebei Province, North China. This fossil species displays a mosaic of characters between <i>Tsuga</i> and <i>Nothotsuga</i>. The well-developed and slightly exserted bract scales of <i>T</i>. <i>weichangensis</i> are reminiscent of <i>Nothotsuga</i>, but other characters, such as nonleaved peduncles and tongue-shaped bract scales, in addition to monosaccate pollen found at the same fossil locality, suggest an affinity closer to <i>Tsuga</i>. Cladistic analysis based on 15 morphological characters and a molecular backbone constraint supports the assignment of these fossil cones to <i>Tsuga</i> rather than <i>Nothotsuga</i>, and places the fossil species of <i>T</i>. <i>weichangensis</i> in an unresolved polytomy within the genus <i>Tsuga</i>. The occurrence of <i>Tsuga</i> seed cone fossils indicate the paleoclimate in the Miocene of Weichang was warmer and more humid than today's climate, which is consistent with the paleoclimate reconstructed by paleopalynology.</p>\",\"PeriodicalId\":17087,\"journal\":{\"name\":\"Journal of Systematics and Evolution\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.7000,\"publicationDate\":\"2023-02-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Systematics and Evolution\",\"FirstCategoryId\":\"1089\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1111/jse.12952\",\"RegionNum\":1,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"Agricultural and Biological Sciences\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Systematics and Evolution","FirstCategoryId":"1089","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/jse.12952","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Agricultural and Biological Sciences","Score":null,"Total":0}
Exceptionally well-preserved seed cones of a new fossil species of hemlock, Tsuga weichangensis sp. nov. (Pinaceae), from the Lower Miocene of Hebei Province, North China
Tsuga (hemlock) is a small genus of 10 extant species in the Pinaceae, with a disjunct distribution in East Asia and eastern and western North America. Reliable species-level identification of Tsuga fossils depends on the discovery of seed cones with intact bracts, but such cones are rare in the fossil record. Here we describe a new fossil species of hemlock as T. weichangensis sp. nov. based on exquisitely preserved seed cones with nearly complete bracts from the Lower Miocene of Weichang, Hebei Province, North China. This fossil species displays a mosaic of characters between Tsuga and Nothotsuga. The well-developed and slightly exserted bract scales of T. weichangensis are reminiscent of Nothotsuga, but other characters, such as nonleaved peduncles and tongue-shaped bract scales, in addition to monosaccate pollen found at the same fossil locality, suggest an affinity closer to Tsuga. Cladistic analysis based on 15 morphological characters and a molecular backbone constraint supports the assignment of these fossil cones to Tsuga rather than Nothotsuga, and places the fossil species of T. weichangensis in an unresolved polytomy within the genus Tsuga. The occurrence of Tsuga seed cone fossils indicate the paleoclimate in the Miocene of Weichang was warmer and more humid than today's climate, which is consistent with the paleoclimate reconstructed by paleopalynology.
期刊介绍:
Journal of Systematics and Evolution (JSE, since 2008; formerly Acta Phytotaxonomica Sinica) is a plant-based international journal newly dedicated to the description and understanding of the biological diversity. It covers: description of new taxa, monographic revision, phylogenetics, molecular evolution and genome evolution, evolutionary developmental biology, evolutionary ecology, population biology, conservation biology, biogeography, paleobiology, evolutionary theories, and related subjects.