PDF(Pubmed)
Abstract：
The biology of extinct animals is usually reconstructed from external morphological characters and comparison with present-day analogues. Internal soft organs are very rarely preserved in fossils and require high-tech approaches for visualization. Here, we report the internal anatomy of a female and male of the ~ 162 Myr-old lobster Eryma ventrosum from the Jurassic La Voulte-sur-Rhône Konservat-Lagerstätte in France using X-ray synchrotron tomography. The Erymidae is an extinct, species-rich, widespread and ecologically important Mesozoic family of decapod crustaceans. Our investigation revealed the anatomy of the locomotory, respiratory, circulatory, excretory, digestive, nervous and sensory, and reproductive systems at a resolution resembling low-magnification histology. Particularly notable is the detailed preservation of the small brain and the fragile hepatopancreas, the main metabolic organ of decapods that decays rapidly post-mortem. The remarkable preservation shows that the internal anatomy of Eryma ventrosum is closer to that of Nephropidae (clawed lobsters) than Astacidae (freshwater crayfish), their closest living relatives based on skeletal morphology. The microanatomy of the gonads and hepatopancreas indicates that the two specimens investigated were a young, well-nourished female and male prior to sexual maturity. The analysis of the soft anatomy reveals remarkable conservatism over 160 Myr and offers new insights into feeding, reproduction, life history and lifestyle of an important component of the macrozoobenthos of Middle Jurassic seas.
摘要：
灭绝动物的生物学通常是从外部形态特征和与当今类似物的比较中重建的。内部软器官很少保存在化石中，需要高科技方法进行可视化。这里,我们使用X射线同步加速器断层摄影术报告了来自法国侏罗纪LaVoulte-sur-RheneKonservat-Lagerstätte的〜162Myr老龙虾Erymaventrosum的雌性和雄性的内部解剖。Erymidae已经灭绝了，物种丰富，广泛且生态重要的中生代十足的甲壳类动物。我们的调查揭示了运动的解剖结构，呼吸,循环,排泄,消化性,神经和感官，和生殖系统的分辨率类似于低放大倍数的组织学。特别值得注意的是小大脑和脆弱的肝胰腺的详细保存，死足动物的主要代谢器官，在死后迅速腐烂。显着的保存表明，Erymaventrosum的内部解剖结构比Astacidae（淡水小龙虾）更接近Nephroidae（爪状龙虾），基于骨骼形态的他们最近的亲戚。性腺和肝胰腺的显微解剖表明，所研究的两个标本是年轻的，在性成熟之前营养良好的女性和男性。对软解剖学的分析揭示了超过160Myr的显着保守主义，并为喂养提供了新的见解，繁殖，侏罗纪中部海域大型底栖动物的重要组成部分的生活史和生活方式。
