ジュラ紀期における両生類のハエとペドモルフィズム
Diying Huang1, André Nel, Chenyang Cai
1State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China. dyhuang@nigpas.ac.cn
Nature
|February 22, 2013
まとめ
以前は寄生虫と考えられていた化石ストラシリドは,特殊なハエ (Diptera) として再分類されています. これらのジュラ紀の昆虫は,以前の解釈とは異なる水中の生活様式を送っていた可能性が高い.
科学分野:
- パレオントロジー・パレオントロジー
- エントモロジー エントモロジー学
- 進化生物学の進化生物学について
背景:
- ストラシリッドは,ロシアと中国の謎のジュラ紀の化石昆虫です.
- 以前は,ペテロサウルスの外寄生虫や羽毛のある恐竜であると仮定されていました.
- 口部と後肢を含む彼らの形態学は,寄生虫の解釈を助長しました.
研究 の 目的:
- ストラシリドの形態学と系統学的配置を再評価する.
- これらの古代昆虫の生態学的役割と生活様式を決定する.
- Insecta.内の彼らの進化的関係を明らかにするために.
主な方法:
- Daohugouの床からのストラシリド化石の詳細な形態学的分析.
- 比較形態は,現存するおよび絶滅した昆虫群,特にディプテラ群との比較形態である.
- 形態学的証拠に基づいて推論された行動の再構築.
主要な成果:
- ストラシリダは高度に専門化されたハエ (ディプテラ) として識別され,絶滅した秩序ではない.
- 大型の膜状の翼,有意な性二形態性,そして独特のペドモルフィックな特徴 (雄の場合は幼虫のを保持している) を表しています.
- 形態学的および行動的特徴は,現存する水生ハエ (Nymphomyiidae) と一致しています.
結論:
- ストラシリッドは水生昆虫または両生類だった可能性が高い.
- 羽を落とすのは水中で交尾するために.
- この研究は,ストラシリドをめぐる長年の分類学および生態学的議論を解決する.
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