Muséum national d'Histoire naturelle, Sorbonne Université, CNRS UMR 7207, CR2P, Centre de Recherche en Paléontologie - Paris, 8 rue Buffon, 75005, Paris, France.
Muséum national d'Histoire naturelle, Sorbonne Université, CNRS UMR 7590, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France.
Sci Rep. 2020 Feb 27;10(1):3574. doi: 10.1038/s41598-020-60282-1.
Crustacean eggs are rare in the fossil record. Here we report the exquisite preservation of a fossil polychelidan embedded within an unbroken nodule from the Middle Jurassic La Voulte-sur-Rhône Lagerstätte (France) and found with hundreds of eggs attached to the pleon. This specimen belongs to a new species, Palaeopolycheles nantosueltae sp. nov. and offers unique clues to discuss the evolution of brooding behaviour in polychelidan lobsters. In contrast to their development, which now relies on a long-lived planktic larval stage that probably did not exist in the early evolutionary steps of the group, the brood size of polychelidan lobsters seems to have remained unchanged and comparatively small since the Jurassic. This finding is at odds with reproductive strategies in other lobster groups, in which a long-lived planktic larval stage is associated with a large brood size.
甲壳动物的卵在化石记录中较为罕见。本文报道了一个中侏罗世法国拉沃尔-苏尔-罗恩层（La Voulte-sur-Rhône Lagerstätte）化石标本的保存情况，该标本是一个完整的结核内保存的多板类标本，其腹部上附有数百枚卵。这个标本属于一个新种，即 Palaeopolycheles nantosueltae sp. nov.，为讨论多板类龙虾的抱卵行为进化提供了独特的线索。与现在依赖于可能在该群体早期进化阶段不存在的长寿命浮游幼体阶段的发育不同，多板类龙虾的抱卵大小自侏罗纪以来似乎保持不变且相对较小。这一发现与其他龙虾类群的繁殖策略不一致，在其他龙虾类群中，长寿命的浮游幼体阶段与较大的抱卵大小有关。
