アンデス山脈で新発見された上トリアシク盆地からの長い首の初期の恐竜
E Martín Hechenleitner1,2, Agustín G Martinelli3,4,5, Sebastián Rocher6,7
1Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires, Argentina. emhechenleitner@gmail.com.
Nature
|October 15, 2025
まとめ
アルゼンチン で 発見 さ れ た 新しい 初期の サウロポドモルフ 恐竜,Huayracursor jaguensis
科学分野:
- 古生物学
- 脊椎動物の進化
- トライアスの生態系
背景:
- トライアス紀後半の陸生生態系は大きな変化を経験し,主要な脊椎動物群の多様化に影響を与えた.
- 初期の恐竜の進化に関する 過去の重要な化石の発見は 南米の特定の盆地に集中していた.
- アルゼンチンの北のプレコーディレラ盆地は,以前は,その古生物学的な重要性のために認識されていなかった.
研究 の 目的:
- 北のプレコーディレラ盆地で 新たに発見された カーニオンの四足の群れを報告する
- 初期のサウロポドモルフであるHuayracursor jaguensisとその進化的影響について説明する.
- トライアス期の脊椎動物と 進化の傾向についての洞察を 提供するためです
主な方法:
- クエブラダ・サンクト・ドミンゴ遺跡のカルニア四足体の発掘と分析.
- 初期のサウロポドモルフの詳細な骨格分析 ハイラクルソールジャグエンシス
- 有名なカーニアンとノリアンサウロポドモルフとの比較分析.
主要な成果:
- 初期のサウロポドモルフのほぼ完全な骨格であるHuayracursor jaguensisの発見
- リンコサウル,シノドント,エトサウルを含む,典型的な後期カルニア動物群の特定.
- カーニアンとノリアン・サウロポドモルフの間で,体量増加と子宮頸部伸縮の始まりを示しています.
結論:
- この発見は 南米のカルニア四足類の 既知の化石記録を 拡張しています
- ハイラクルサー・ジャグエンシスは,サウロポドモルフの進化の初期に体長と首の長さの増加を意味する重要な証拠です.
- この発見は トライアス紀後期の恐竜の多様化を理解するのに役立ちます
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