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1. The Ediacaran frondose fossil Arborea from the Shibantan limestone of South China

   https://doi.org/10.1017/jpa.2020.43  

   Wang, Xiaopeng; Pang, Ke; Chen, Zhe; Wan, Bin; Xiao, Shuhai; Zhou, Chuanming; Yuan, Xunlai (November 2020, Journal of Paleontology)

   Abstract Bituminous limestone of the Ediacaran Shibantan Member of the Dengying Formation (551–539 Ma) in the Yangtze Gorges area contains a rare carbonate-hosted Ediacara-type macrofossil assemblage. This assemblage is dominated by the tubular fossil Wutubus Chen et al., 2014 and discoidal fossils, e.g., Hiemalora Fedonkin, 1982 and Aspidella Billings, 1872, but frondose organisms such as Charnia Ford, 1958, Rangea Gürich, 1929, and Arborea Glaessner and Wade, 1966 are also present. Herein, we report four species of Arborea from the Shibantan assemblage, including the type species Arborea arborea (Glaessner in Glaessner and Daily, 1959) Glaessner and Wade, 1966, Arborea denticulata new species, and two unnamed species, Arborea sp. A and Arborea sp. B. Arborea arborea is the most abundant frond in the Shibantan assemblage. Arborea denticulata n. sp. resembles Arborea arborea in general morphology but differs in its fewer primary branches and lower length/width ratio of primary branches. Arborea sp. A and Arborea sp. B are fronds with a Hiemalora -type basal attachment. Sealing by microbial mats and authigenic cementation may have played an important role in the preservation of Arborea in the Shibantan assemblage. The Shibantan material of Arborea extends the stratigraphic, ecological, and taphonomic ranges of this genus. UUID: http://zoobank.org/554f21da-5f09-4891-9deb-cbc00c41e5f1 

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2. Inferring the evolution of reproductive isolation in a lineage of fossil threespine stickleback, Gasterosteus doryssus

   https://doi.org/10.1098/rspb.2024.0337  

   Siddiqui, Raheyma; Swank, Samantha; Ozark, Allison; Joaquin, Franklin; Travis, Matthew P; McMahan, Caleb D; Bell, Michael A; Stuart, Yoel E (April 2024, Proceedings of the Royal Society B: Biological Sciences)

   Darwin attributed the absence of species transitions in the fossil record to his hypothesis that speciation occurs within isolated habitat patches too geographically restricted to be captured by fossil sequences. Mayr's peripatric speciation model added that such speciation would be rapid, further explaining missing evidence of diversification. Indeed, Eldredge and Gould's original punctuated equilibrium model combined Darwin's conjecture, Mayr's model and 124 years of unsuccessfully sampling the fossil record for transitions. Observing such divergence, however, could illustrate the tempo and mode of evolution during early speciation. Here, we investigate peripatric divergence in a Miocene stickleback fish,Gasterosteus doryssus.This lineage appeared and, over approximately 8000 generations, evolved significant reduction of 12 of 16 traits related to armour, swimming and diet, relative to its ancestral population. This was greater morphological divergence than we observed between reproductively isolated, benthic-limnetic ecotypes of extantGasterosteus aculeatus. Therefore, we infer that reproductive isolation was evolving.However, local extinction ofG. doryssuslineages shows how young, isolated, speciating populations often disappear, supporting Darwin's explanation for missing evidence and revealing a mechanism behind morphological stasis. Extinction may also account for limited sustained divergence within the stickleback species complex and help reconcile speciation rate variation observed across time scales. 

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3. Eocene Fossil Legume Leaves Referable to the Extant Genus Arcoa (Caesalpinioideae, Leguminosae)

   https://doi.org/10.1086/701468  

   Herendeen, Patrick S.; Herrera, Fabiany (March 2019, International Journal of Plant Sciences)
4. Nomenclatural and taxonomic notes on the fossil pollen genus Sparganiaceaepollenites Thiergart 1937

   https://doi.org/10.1080/01916122.2025.2463407  

   De_Benedetti, Facundo; Zamaloa, María C; Gandolfo, María A; Cúneo, Néstor R; Fensome, Robert A; Gravendyck, Julia (March 2025, Palynology)

   The nomenclature and status of the fossil-genus Sparganiaceaepollenites Thiergart 1937 and several of its species are problematic. We confirm the status of the genus and provide an emended description for it to accommodate new characters that were recently described in some species. We note that (i) the name Sparganiaceaepollenites microreticulatus Grabowska and Wa?y?ska 2009 from the Miocene of Poland is illegitimate according to the rules of the International Code of Nomenclature for algae, fungi, and plants, as a later homonym of Sparganiaceaepollenites microreticulatus Kar and Jain 1981 from the Miocene of India; (ii) the name Sparganiaceaepollenites reticulatus Samant et al. 2022 from the Maastrichtian of India is illegitimate as a later homonym of Sparganiaceaepollenites reticulatus Doktorowicz-Hrebnicka 1960 ex Krutzsch and Vanhoorne 1977 from the Miocene of Poland; and (iii) the name Sparganiaceaepollenites annulatus Thakre et al. 2024 from the Danian of India is illegitimate as a later homonym of Sparganiaceaepollenites annulatus De Benedetti 2023 from the Maastrichtian?Danian of Argentina. We propose the new names (i) Sparganiaceaepollenites oczkowicensis nom. nov. subst. pro Sparganiaceaepollenites microreticulatus Grabowska and Wa?y?ska; and (ii) Sparganiaceaepollenites intertrappeansis nom. nov. subst. pro S. reticulatus Samant et al. (an emended description is provided). Additionally, Sparganiaceaepollenites annulatus Thakre et al. is considered a heterotypic synonym of Sparganiaceaepollenites intertrappeansis nom. nov. 

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5. A Palaeogene stem crotaphytid ( Aciprion formosum ) and the phylogenetic affinities of early fossil pleurodontan iguanians

   https://doi.org/10.1098/rsos.221139  

   Scarpetta, Simon G (January 2024, Royal Society Open Science)

   Pleurodonta is an ancient, diverse clade of iguanian lizard distributed primarily in the Western Hemisphere. Although the clade is a frequent subject of systematic research, phylogenetic resolution among the major pleurodontan clades is elusive. That uncertainty has complicated the interpretations of many fossil pleurodontans. I describe a fossil skull of a pleurodontan lizard from the Palaeogene of Wyoming that was previously allocated to the puzzling taxonAciprion formosum, and provide an updated morphological matrix for iguanian lizards. Phylogenetic analyses using Bayesian inference demonstrate that the fossil skull is the oldest and first definitive stem member of Crotaphytidae (collared and leopard lizards), establishing the presence of that clade in North America during the Palaeogene. I also discuss new or revised hypotheses for the relationships of several early pleurodontans. In particular, I examine potential evidence for crown-Pleurodonta in the Cretaceous of Mongolia (Polrussia), stem Pleurodonta in the Cretaceous of North America (Magnuviator) and a stem anole in the Eocene of North America (Afairiguana). I suggest that the placement of the fossil crotaphytid is stable to the uncertain phylogeny of Pleurodonta, but recognize the dynamic nature of fossil diagnosis and the potential for updated systematic hypotheses for the other fossils analysed here. 

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