Ren Hirayama

1.6k total citations
52 papers, 1.2k citations indexed

About

Ren Hirayama is a scholar working on Paleontology, Nature and Landscape Conservation and Global and Planetary Change. According to data from OpenAlex, Ren Hirayama has authored 52 papers receiving a total of 1.2k indexed citations (citations by other indexed papers that have themselves been cited), including 44 papers in Paleontology, 36 papers in Nature and Landscape Conservation and 13 papers in Global and Planetary Change. Recurrent topics in Ren Hirayama's work include Paleontology and Evolutionary Biology (38 papers), Turtle Biology and Conservation (26 papers) and Evolution and Paleontology Studies (20 papers). Ren Hirayama is often cited by papers focused on Paleontology and Evolutionary Biology (38 papers), Turtle Biology and Conservation (26 papers) and Evolution and Paleontology Studies (20 papers). Ren Hirayama collaborates with scholars based in Japan, United States and Russia. Ren Hirayama's co-authors include Igor G. Danilov, Donald B. Brinkman, Haiyan Tong, Yuichirou Yasukawa, Yasuhisa Nakajima, Hideki Endo, Shinji Isaji, Eugene S. Gaffney, Diógenes de Almeida Campos and Tsutomu Hikida and has published in prestigious journals such as Nature, Biological Journal of the Linnean Society and Journal of Vertebrate Paleontology.

In The Last Decade

Ren Hirayama

49 papers receiving 1.1k citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Ren Hirayama Japan 17 984 882 256 71 50 52 1.2k
Linda A. Tsuji Germany 19 1.1k 1.1× 602 0.7× 197 0.8× 49 0.7× 31 0.6× 27 1.2k
Baâdi Bouya Morocco 26 1.2k 1.2× 721 0.8× 230 0.9× 109 1.5× 44 0.9× 32 1.3k
Adam K. Huttenlocker United States 23 1.2k 1.2× 517 0.6× 236 0.9× 88 1.2× 70 1.4× 53 1.3k
Ronan Allain France 23 1.2k 1.3× 836 0.9× 187 0.7× 43 0.6× 28 0.6× 47 1.3k
Fabien Knoll Spain 23 1.3k 1.3× 801 0.9× 246 1.0× 96 1.4× 24 0.5× 71 1.4k
Joseph J. W. Sertich United States 20 1.2k 1.2× 784 0.9× 209 0.8× 37 0.5× 54 1.1× 42 1.2k
Mohamed Iarochène France 14 975 1.0× 627 0.7× 191 0.7× 59 0.8× 24 0.5× 15 1.0k
Attila Ősi Hungary 26 1.8k 1.8× 1.1k 1.2× 328 1.3× 59 0.8× 41 0.8× 82 1.9k
Andrea Cau Italy 25 1.5k 1.5× 921 1.0× 225 0.9× 79 1.1× 27 0.5× 60 1.6k
Juliana Sterli Argentina 24 1.4k 1.5× 1.1k 1.3× 391 1.5× 44 0.6× 40 0.8× 62 1.6k

Countries citing papers authored by Ren Hirayama

Since Specialization
Citations

This map shows the geographic impact of Ren Hirayama's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Ren Hirayama with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Ren Hirayama more than expected).

Fields of papers citing papers by Ren Hirayama

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Ren Hirayama. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Ren Hirayama. The network helps show where Ren Hirayama may publish in the future.

Co-authorship network of co-authors of Ren Hirayama

This figure shows the co-authorship network connecting the top 25 collaborators of Ren Hirayama. A scholar is included among the top collaborators of Ren Hirayama based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Ren Hirayama. Ren Hirayama is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Pérez‐García, Adán, et al.. (2023). The First Side-Necked Turtle (Pleurodira, Bothremydidae) from the Campanian (Late Cretaceous) of Egypt. Diversity. 15(2). 284–284. 3 indexed citations
2.
Matsumoto, Ryoko, et al.. (2021). The first choristoderan record from the Upper Cretaceous of Asia, Tamagawa Formation, Kuji Group, Japan. Cretaceous Research. 129. 104999–104999. 1 indexed citations
3.
Takahashi, Masamichi, Patrick S. Herendeen, Fabiany Herrera, et al.. (2021). A New Assemblage of Plant Mesofossils (Late Turonian–Middle Santonian; Upper Cretaceous) from the Tamagawa Formation, Kuji Group, in Northeastern Japan. Paleontological Research. 25(2). 1 indexed citations
4.
Varricchio, David J., et al.. (2019). New occurrence of Neurankylus sp. (Testudines: Paracryptodiria: Baenidae) in the Upper Cretaceous Frontier Formation of south western Montana (USA). Cretaceous Research. 108. 104318–104318. 2 indexed citations
5.
Vitek, Natasha, Igor G. Danilov, Yasuhisa Nakajima, & Ren Hirayama. (2017). Redescription of the skull of ‘ Trionyx’ kyrgyzensis and improved phylogenetic taxon sampling of Cretaceous and Palaeogene soft-shelled turtles (Trionychidae) of Asia, including the oldest crown trionychids. Journal of Systematic Palaeontology. 16(3). 199–211. 13 indexed citations
6.
Nakajima, Yasuhisa, Igor G. Danilov, Ren Hirayama, T Sonoda, & Torsten M. Scheyer. (2017). Morphological and histological evidence for the oldest known softshell turtles from Japan. Journal of Vertebrate Paleontology. 37(2). e1278606–e1278606. 12 indexed citations
7.
Nakajima, Yasuhisa, Ren Hirayama, & Hideki Endo. (2014). Turtle humeral microanatomy and its relationship to lifestyle. Biological Journal of the Linnean Society. 112(4). 719–734. 56 indexed citations
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Tong, Haiyan & Ren Hirayama. (2008). A new species of Argillochelys (Testudines: Cryptodira: Cheloniidae) from the Ouled Abdoun phosphate basin, Morocco. Bulletin de la Société Géologique de France. 179(6). 623–630. 23 indexed citations
11.
Isaji, Shinji, et al.. (2006). Pictorial Terrestrial Fossil Assemblages of the Middle Pleistocene Kiyokawa Formation, Shimosa Group in Yoshinoda, Sodegaura City, Chiba Prefecture. The Quaternary Research (Daiyonki-Kenkyu). 45(3). i–ii. 1 indexed citations
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Hirayama, Ren, et al.. (2006). Fossil Turtles from the Kiyokawa Formation of the Shimosa Group (Pleistocene) at Chiba Prefecture. The Quaternary Research (Daiyonki-Kenkyu). 45(3). 179–187. 5 indexed citations
14.
Hirayama, Ren, Akira Fujii, & Keiichi Takahashi. (2006). A dermochelyid sea turtle from the upper cretaceous (Late Campanian) Izumi Group of Shionoe, Takamatsu City, Kagawa Prefecture, Western Japan. 17–20. 3 indexed citations
15.
Okazaki, Hiroko, Ren Hirayama, Shinji Isaji, et al.. (2004). Flood-plain Deposits and Fossil Assemblages of the Middle Pleistocene Kiyokawa Formation, Shimosa Group, Eastern Japan. The Quaternary Research (Daiyonki-Kenkyu). 43(5). 359–366. 13 indexed citations
16.
Diedrich, Cajus G. & Ren Hirayama. (2003). Turtle remains (Testudines, Chelonioidea) from the Middle Turonian of northwest Germany. Netherlands Journal of Geosciences – Geologie en Mijnbouw. 82(2). 161–167. 7 indexed citations
17.
Gaffney, Eugene S., Diógenes de Almeida Campos, & Ren Hirayama. (2001). Cearachelys, a new side-necked turtle (Pelomedusoides, Bothremydidae) from the early Cretaceous of Brazil. American Museum novitates ; no. 3319. American Museum Novitates. 4 indexed citations
18.
Hirayama, Ren, Donald B. Brinkman, & Igor G. Danilov. (2000). DISTRIBUTION AND BIOGEOGRAPHY OF NON-MARINE CRETACEOUS TURTLES. Russian Journal of Herpetology. 7(3). 181–198. 134 indexed citations
19.
Hirayama, Ren, et al.. (1994). A huge fossil soft-shelled turtle from the Miocene Bihoku Group of western Japan and its paleoenvironmental significance. The Journal of the Geological Society of Japan. 100(4). 316–318_1. 1 indexed citations
20.
Hirayama, Ren. (1992). Fossil Turtles from the Neogene Strata in the Sinda Basin, Eastern Zaire. Kyoto University Research Information Repository (Kyoto University). 17(17). 49–65. 16 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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