Figure - available from: Frontiers in Plant Science
This content is subject to copyright.
Fossil pods of Podocarpium eocenicum sp. nov. (A) Dehisced pod with distinct prominent base (arrowhead) in the stipe. CC254a. (B) Counterpart of (A). CC254b. (C) Dehisced pod. CC1298. (D–H) Indehisced pod. (D) CC1162b. (E) CC1216a. (F) Indehisced pod wih distinct venations on the valve. CC1100a. (G) Counterpart of (F). CC1100b. (H) Incomplete pod with a long stipe and clear venation. CC1217. (I) Dehisced pod with venation structures. CC1164. (J,K) Indehisced pod. (J) MMJ1–002. (K) MMJ1–003a. Scale bar = 1 cm.
Source publication
Podocarpium A. Braun ex Stizenberger is one of the most common legumes in the Neogene of Eurasia, including fossil fruits, seeds, leaves, and possible flower and pollen grains. This genus is not completely consistent with any extant genera according to gross morphological characters and poorly preserved cuticular structures reported in previous stu...
Citations
... This speculation is corroborated by the presence of other Oligocene fossil angiosperms found in the Huatugou region. For example, Podocarpium, an extinct genus well-documented in the Cenozoic deposits around Eurasia Xu et al., 2015), is abundant in the Oligocene Qaidam Basin (Yan et al., 2018;Han et al., 2020;Song et al., 2020). It is also known from the Oligocene of south China, central Europe, and western Europe (Fig. 7a). ...
Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau, China relieson discovering new plant fossils. The Qaidam Basin has long been regarded as an ideal ‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan Plateau. However,fossil angiosperms from the Qaidam Basin are rare, and our knowledge of its paleovegetation is poor.Here, we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou For-mation of northwestern Qaidam Basin (Huatugou area). Comparative morphological analysis led us toassign the fruits to the Betula subgenus Betula and the leaves to Carpinus grandis. These findings, togetherwith other reported fossil plants from the same locality, reveal a close floristic linkage between theQaidam Basin and Europe during the Oligocene. The northern pathway of this floristic exchange mayhave crossed through the Qaidam Basin during the late Paleogene. This floristic linkage may have beenfacilitated by the continuous narrowing of the Turgai Strait and stronger westerlies, which transportedmoisture and provided favorable climatic conditions. Indeed, fossil plants collected from the QaidamBasin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been asuitable region for these plants to flourish and spread during the Oligocene.
... There has been much debate about the nomenclature and the taxonomy of this genus (Stizenberger, 1851;Heer, 1859;Chaney, 1933;Hantke, 1954;Gregor and Hantke, 1980;Herendeen, 1992a). Until now, it has been widely accepted that Podocarpium belongs to the subfamily Caesalpinioideae based on detailed morphological comparison (Xu et al., 2015;Li et al., 2019;Han et al., 2020). Podocarpium is one of the most common legumes found in Cenozoic sediments of Eurasia comprising only two fossil species, namely P. podocarpum (A.Braun) Herendeen and P. eocenicum Xu et Jin (Herendeen, 1992a;Xu et al., 2015). ...
... Until now, it has been widely accepted that Podocarpium belongs to the subfamily Caesalpinioideae based on detailed morphological comparison (Xu et al., 2015;Li et al., 2019;Han et al., 2020). Podocarpium is one of the most common legumes found in Cenozoic sediments of Eurasia comprising only two fossil species, namely P. podocarpum (A.Braun) Herendeen and P. eocenicum Xu et Jin (Herendeen, 1992a;Xu et al., 2015). Following Heer (1859) the genus has been widely reported in Europe, China, and Japan from the Eocene to the Pliocene (Chaney, 1933;Ishida, 1970;WGCPC, 1978;Gregor, 1985;Li et al., 1987;Guo and Zhou, 1992;Liu et al., 2001;Teodoridis, 2003a;Kvacek and Teodoridis, 2007;Wang et al., 2007). ...
... Morphological measurements were obtained using ImageJ software (http://imagej.nih.gov/ij/). The description of these fossil specimens is based on previous morphological terminology used for Podocarpium pods (Herendeen, 1992a;Xu et al., 2015;Han et al., 2020). ...
Podocarpium is an extinct genus in Fabaceae with rich fossil records in Eurasia dating back to the Eocene. However, the diversification and biogeographic histories of Podocarpium are poorly known due to a lack of fossils in some key regions, such as the Tibetan Plateau, an area recently shown to be crucial for floristic exchanges worldwide in the geological past. Here, we describe well-preserved fossil pods of Podocarpium from the late Eocene (~ 35 Ma) of the Lunpola Basin, central Tibetan Plateau, China. Together with detailed morphological observation and geometric morphology analysis, these fossil pods are named Podocarpium tibeticum W.-C. Li, J. Huang et T. Su sp. nov., characterized by asymmetrical elliptical valves, olecranon fruit beak, and a clearly oblique base. This material comprises the oldest fossil record of Podocarpium from the Tibetan Plateau and adjacent regions. The discovery of P. tibeticum shows Podocarpium was present in central Tibet by the late Eocene. Together with previous fossil records, it indicates that Podocarpium may have originated in East Asia, migrated into the central valley of Tibet in the late Eocene, and then spread westward to Europe through a low-latitude path of island chains along the Neotethys. Results of paleoecological niche modeling demonstrate that Podocarpium had an almost worldwide potential distribution range in the Eocene, but this sharply contracted thereafter until by the Pliocene it was restricted to a small area of East Asia. Generally, this finding further supports the idea that what is now the central Tibetan Plateau was a globally significant hub for Paleogene floristic exchange.
... During this period, the tropic zone of southern China became humid (Sun and Wang, 2005;Quan et al., 2012), allowing northward movement of freshwater crabs from the Indochina Peninsula to southwestern China. Similar pattern was also observed in other species (e.g., Xu et al., 2015;Janssens et al., 2016). With the development of humid conditions in southern China (Sun and Wang, 2005;Herman et al., Fig. 3. Divergence time estimation using three fossil calibration points. ...
The Asian potamid subfamily Potamiscinae is the most species‐rich group of primary freshwater crabs in the world, and a large number of these (318 species in 52 genera) are found in China where they exhibit a remarkably high rate of endemism. However, the evolutionary history and phylogenetic relationships of this subfamily is still poorly understood and the hypothesis that the Chinese potamids originated in the Indochina Peninsula has yet to be tested using a modern phylogeographic reconstruction and molecular dating methods. Here we analyze the phylogenetic relationships and biogeographic history of the Chinese potamiscines based on whole mitogenomes of 72 species of Asian freshwater crabs representing 65% of the potamiscine genera found in China, including new mitogenome sequences for 57 species. The mitogenomic phylogeny generated four separate clades: Southwest China (SWC), Indochina‐Southwest China (ISWC), Central China (CC), and South China‐adjacent Islands (SCI). Our results suggest that the Chinese potamiscine fauna most likely originated in Indochina during the Eocene. The establishment of the East Asian monsoon during the Eocene/Oligocene resulted in major climate changes that coincide with the local diversification of the CC and SCI clades. In addition, diversification of two other clades (ISWC and SWC) may have been driven by past large scale environmental changes taking place at that time such as increased local precipitation and expanding freshwater habitats associated with the uplifting of the Hengduan Mountains. In addition, our phylogenies did not support monophyly for six currently recognized potamiscine genera, highlighting the need for further taxonomic revisions of this fauna. The broad taxonomic sampling and well‐supported molecular phylogenies used here allow for the updating of our understanding of the evolutionary origins and diversification of the potamiscine freshwater crabs in China.
... and Papilionoideae Giseke (Gunn 1984(Gunn , 1991EBFC 1988EBFC , 1993EBFC , 1994EBFC , 1995Lin et al. 2014). Diverse and abundant fossil records of Leguminosae were discovered from Cenozoic sediments in recent decades (EBCPC 1978;Herendeen et al. 1992;Sun et al. 1999;Jia et al. 2017;Ma et al. 2017); however, the early biogeographical history of legumes remains ambiguous (Ma et al. 2017), and new discoveries of leguminous fossils can provide important information to realise the early biogeography and the diversification history of this large family (Wang et al. 2010;Jia et al. 2014Jia et al. , 2017Xu et al. 2015;Ma et al. 2017). Recently, some fossil legumes were discovered from the Oligocene Shangganchaigou Formation of Qaidam Basin, Qinghai Province, China. ...
Fossils are critical for understanding the environmental changes and uplift history of the Tibetan Plateau during the Cenozoic. As the largest inland basin located at the northeastern plateau, Qaidam Basin has been regarded as the key region to understand the climatic changes in the plateau during the Cenozoic. Herein, fossil legumes from the Oligocene Shangganchaigou Formation in northwestern Qaidam Basin have been reported and are assigned to Desmanthus cf. virgatus (L.) Willd. based on morphological comparison. Current materials represent the first megafossil record of this genus in the world. The living analogues of current fossils now live in regions with mean annual temperature values (MAT) ranging from 13.4 to 29.1°C and mean annual precipitation values (MAP) ranging from 36 to 2874 mm while the MAT and MAP of current northwestern Qaidam Basin is −1.03°C and 60.5 mm, respectively, and indicate that the Oligocene Qaidam was much warmer than today. We calculate that current fossils could grow no higher than 2492 m considering the climatic condition of the Oligocene Qaidam. The difference between estimated and modern elevation of the fossil site suggests that the elevation of the research area has increased by at least ≈1000 m since the Oligocene. ARTICLE HISTORY
... Characterized by its single-seeded legume pod and compound leaves, its megafossils have been found in the Eocene to Pliocene of China, the Oligocene and Miocene of Central Europe and the Miocene of Japan (Fig. 1,Table S1 and references therein). After the first occurrence of Podocarpium eocenicum in the middle Eocene in southernmost China (Xu et al., 2015), this genus subsequently expanded its range from South China to Europe and then reached its maximum distribution in the Miocene in Eurasia (Liu et al., 2001;Wang et al., 2007a). However, in contrast to the numerous fossil records in the Miocene, the Oligocene records of Podocarpium are much fewer in Eastern Asia with only some fruits and leaflets reported Li et al., 2019). ...
... enable us to assign the fossil fruit to Podocarpium podocarpum (A. Braun) Herendeen (Herendeen, 1992a;Wang et al., 2007a;Xu et al., 2015;Li et al., 2019). ...
... Two species of Podocarpium fruits have been described to date: P. eocenicum proposed based on material from the Eocene of South China (Xu et al., 2015), and P. podocarpum based on material from the Miocene of Switzerland and southern Germany (Heer, 1859). As proposed by Xu et al. (2015), these two species mainly differ in the presence of valve venation and the ratio of stipe length to valve length. ...
The extinct legume genus Podocarpium first appeared in the middle Eocene of South China and then became widely distributed throughout Eurasia during the Oligocene andMiocene. Fossil records fromCentral Asia are important for understanding the patterns of floristic change of Podocarpium between Eastern Asia and Europe, but they are relatively rare. Here, we describe well-preserved fossil fruits and leaves of Podocarpium podocarpum (A. Braun) Herendeen from the early Oligocene (Rupelian) of the Qaidam Basin, northwest China. Morphological comparison among fossil fruits of all Podocarpium reported so far confirms the difference in fruit shape between
Podocarpium eocenicum and P. podocarpum, and shows a decrease in fruit size during the Oligocene, which might be a response from this thermophilous plant to a cooler condition. The presence of P. podocarpum in the early Oligocene of Qaidam suggests that the Qaidam Basin might play an important role in the migration of this genus between Eastern Asia and Europe during the early Oligocene. Moreover, the expansion of Podocarpium in China during the Cenozoic appears to be strongly influenced by the East Asia monsoon development.
... The climate became progressively colder, reaching the minimum at the end of this period (Pavlyutkin and Golozoubov, 2010). The cooling caused further aridifi cation (Sun and Wang, 2005;Xu et al., 2015), eventually leading to separation of the American-Asian and East Asian ranges, consolidation of the existing disjunctions, and formation of new ones. As shown by the genetic data, the East Asian genus Grylloblattina Bey-Bienko, 1951 and the West American genus Grylloblatta Walker, 1914 (Grylloblattidae) were separated in the Late Oligocene or Early Miocene (Fig. 2E) ( Schoville and Kim, 2011). ...
The distributions of ground beetle taxa endemic to the Sikhote-Alin Mountains are analyzed at the level of related groups. The “centers of endemism” and the “main boundaries” are delineated in the Sikhote-Alin territory, and the altitudinal and habitat preferences of the endemics are analyzed. The main stages in the formation of the recent endemic ground beetle fauna of the Sikhote-Alin are determined. The absence of complete ice cover in the Pleistocene allowed the Sikhote-Alin fauna to develop for a long time without epochs of complete destruction. The forest vegetation preserved in the south and east of the Sikhote-Alin during the Pleistocene glaciation served as a major refugium for the Tertiary North Asian fauna.
... India: Shukla and Mehrotra (2016). China: Xu et al. (2015). ...
Leguminosae are one of the most diverse flowering-plant groups today, but the evolutionary history of
the family remains obscure because of the scarce early fossil record, particularly from lowland tropics. Here, we report
~500 compression or impression specimens with distinctive legume features collected from the Cerrejón and Bogotá
Formations, Middle to Late Paleocene of Colombia. The specimens were segregated into eight fruit and six leaf
morphotypes. Two bipinnate leaf morphotypes are confidently placed in the Caesalpinioideae and are the earliest
record of this subfamily. Two of the fruit morphotypes are placed in the Detarioideae and Dialioideae. All other fruit
and leaf morphotypes show similarities with more than one subfamily or their affinities remain uncertain. The abundant
fossil fruits and leaves described here show that Leguminosae was the most important component of the earliest rainforests
in northern South America c. 60–58 million years ago.
... Климат в этот период становится еще холоднее, достигнув минимума в его конце (Павлюткин, Голозубов, 2010). Продолжающееся похолодание вызывает дальнейшую аридизацию (Sun, Wang, 2005;Xu et al., 2015), что приводит к постепенному разрыву американо-азиатских и восточноазиатских ареалов, закреплению уже образовавшихся дизъюнкций и возникновению новых. Генетические исследования показали, что поздний олигоцен -ранний миоцен являются временем обособления восточноазиатского рода Grylloblattina Bey-Bienko 1951 и западно-американского Grylloblatta Walker 1914 (Grylloblattidae) (рис. ...
An analysis of the distributions of the ground beetles endemic to the Sikhote-Alin’ Mountains in the scope of related groups is given. “Centers of endemism” and “the main lines” over the territory of Sikhote-Alin’ are delineated. An analysis of the altitudinal and habitat restrictions of the endemics is presented. The main stages in the formation of the modern endemic ground beetle fauna of the Sikhote-Alin’ are determined. The absence from the Sikhote-Alin’ of glaciations in the Pleistocene might have allowed for its fauna to be developed for a long time without epochs of complete destruction. The preserved forest vegetation in the south and east of the Sikhote-Alin’ in the Pleistocene could have become one of the most important refugia for the Tertiary fauna of North Asia.
Проанализированы ареалы эндемичных жужелиц Сихотэ-Алиня в объеме родственных групп. Выделены “центры эндемизма” и “главные рубежи” на территории Сихотэ-Алиня. Дан анализ особенностей высотно-биотопической приуроченности эндемиков. Выделены главные этапы формирования современной эндемичной фауны жужелиц Сихотэ-Алиня. Выяснено, что отсутствие покровного оледенения в плейстоцене позволило фауне Сихотэ-Алиня в течение длительного периода формироваться без эпох полного уничтожения. Благодаря сохранившейся в плейстоцене лесной растительности на юге и востоке Сихотэ-Алиня, этот район стал важнейшим рефугиумом для третичной фауны Северной Азии.
... The Leguminosae are also very important in the modern flora of China, including about 167 genera and 1673 species (LPWG, 2013a(LPWG, , 2013b. However, leguminous fossils are only occasionally reported from China (Guo and Zhou, 1992;Wang et al., 2007;Wang et al., 2010Wang et al., , 2014Lin et al., 2015;Xu et al., 2015a;Ma et al., 2017;Jia et al., 2017;Li et al., 2017Li et al., , 2019Yan et al., 2018). The most commonly known fossil legume in China is Podocarpium A. Braun ex Stizenberger (Wang et al., 2007;Ma et al., 2017;Xu et al., 2015a;Yan et al., 2018;Li et al., 2019). ...
... However, leguminous fossils are only occasionally reported from China (Guo and Zhou, 1992;Wang et al., 2007;Wang et al., 2010Wang et al., , 2014Lin et al., 2015;Xu et al., 2015a;Ma et al., 2017;Jia et al., 2017;Li et al., 2017Li et al., , 2019Yan et al., 2018). The most commonly known fossil legume in China is Podocarpium A. Braun ex Stizenberger (Wang et al., 2007;Ma et al., 2017;Xu et al., 2015a;Yan et al., 2018;Li et al., 2019). It is an extinct genus and its relationships to extant leguminous genera are still unclear (Wang et al., 2007;Li et al., 2019). ...
The Leguminosae are the third-largest angiosperm family with crucial floristic and ecological importance in major biomes, especially in tropical rainforests. However, reliable fossils of the family are not common in East Asia, rendering a poor understanding of the diversification and biogeographic history of the Leguminosae in this region. In this paper we described a new species of Ormosia (Leguminosae: Papilionoideae) based on compressed fruits (legumes) from the middle Miocene of Fujian in southeastern China. Ormosia zhangpuensis sp. nov. is an obovate to broadly elliptical fruit with acuminate apex, and constricted, neck-like base. Each fruit contains one single seed. External cuticle of pericarp has trichome bases and randomly oriented, anomocytic stomata. The studied fossils provide a new evidence for the diversity of the Leguminosae in East Asia during the Neogene. Fossil records also indicate that Ormosia had expanded its distribution southwards, probably in response to the global climatic cooling during the Cenozoic.
... Meantime, they also related many dispersed pollen records of Fupingopollenites (Tricolporopollenites) and several other taxa from the Paleogene and Neogene of Eurasia to Podocarpium (Liu et al., 2001: Table 2). Nevertheless, as mentioned by Wang et al. (2007) and Xu et al. (2015a), many palynological researches considered that the pollen genus Fupingopollenites is possibly related to other dicotyledonous taxa (Song et al., 1999(Song et al., , 2004Wang and Harley, 2004). Thereby, because Fupingopollenites shows such an uncertain affinity, the biogeographic pattern and eastern Asian origin hypothesis of Podocarpium proposed by Liu et al. (2001) based on the pollen stratigraphical occurrences need to be reevaluated. ...
... Thereby, because Fupingopollenites shows such an uncertain affinity, the biogeographic pattern and eastern Asian origin hypothesis of Podocarpium proposed by Liu et al. (2001) based on the pollen stratigraphical occurrences need to be reevaluated. Recently, Xu et al. (2015a) added a fossil species P. eocenicum to this otherwise monospecific genus Podocarpium based on many fruits from the middle Eocene of Hainan and Guangdong, South China. Thus, this discovery of P. eocenicum in low latitudes of South China surprisingly confirms the previous inference of Liu et al. (2001) on the eastern Asian origin of Podocarpium. ...
... Up to now, many fossil specimens of Podocarpium, including fruits, seeds and leaves, have been described from the Eocene or Neogene deposits of eastern Asia (Ishida, 1970;Wang et al., 2007;Xu et al., 2015a) and the Oligocene to Miocene of Central Europe (Hably, 1992;Kovar-Eder et al., 2004). But no Oligocene record has been hitherto documented in China, and even eastern Asia (Xu et al., 2015a). ...
Podocarpium (Fabaceae), characterized by single seeded pods and paripinnate compound leaves, is well known as an extinct legume genus having extensive fossil occurrences from the Miocene of Central Europe and eastern Asia. However, the Palaeogene unambiguous megafossils are quite scarce, especially the Oligocene record from eastern Asia, which heavily impedes our understanding of early dispersal patterns and infrageneric relationships of this enigmatic genus. Here, we described dozens of legume specimens from the Oligocene Ningming Formation of Guangxi in South China, the Early Miocene Guide Group of Qinghai in Northwest China and the Middle–Late Miocene Shengxian Formation of Zhejiang in Southeast China as Podocarpium podocarpum (A. Braun) Herendeen based on extremely similar fruit characters. Meanwhile, we reexamined variation in fruit morphology among the previously reported fruits of Eurasia and present legumes as a basis for interpreting the infrageneric relationship and subfamily affinity of Podocarpium. The high similarities presented by these fossil fruits support the previous recognition of the specimens from the Oligocene–Miocene of Central Europe and the Miocene– Pliocene of eastern Asia as P. podocarpum, but such a low species diversity of Podocarpium appears to indicate a bradytelic morphological evolution for this whole ancient lineage through geologic time. Moreover, judging from seed orientation as well as seed and fruit comparative sizes, the oblong seed is parallel to the long axis of the fruit and its placentation is near the apex of the seed chamber, which favor the previous assignment of Podocarpium to the subfamily Caesalpinioideae. Additionally, we speculated that this extinct genus may prefer a warm and humid (or mildly arid) environment by plotting the megafossil localities on the overall Eocene, Oligocene and Miocene palaeoclimate maps based on continental drift. The Oligocene occurrence from the Ningming Formation in Guangxi, South China sheds new light on the historical biogeographical pattern between Central Europe and eastern Asia, i.e. after the probable origin in low latitude tropic coastal regions of southernmost South China (i.e. Hainan) by the Middle Eocene, Podocarpium may subsequently disperse into Guangxi and then Europe via a probable low-latitude land connection located among the Tethys and Paratethys seas to the southwest of Eurasia in the Early Oligocene, independent of the gradual closure of the Turgai Strait in the middle-high latitudes during the Oligocene.
