Paläontologisches Institut und Museum, Universität Zürich, Karl-Schmid-Strasse 4, 8006, Zurich, Switzerland.
Parc national de Miguasha, 231 Route de Miguasha Ouest, Nouvelle, QC, G0C 2E0, Canada.
Sci Rep. 2021 Sep 24;11(1):19039. doi: 10.1038/s41598-021-98362-5.
Like other soft-bodied organisms, ctenophores (comb jellies) produce fossils only under exceptional taphonomic conditions. Here, we present the first record of a Late Devonian ctenophore from the Escuminac Formation from Miguasha in eastern Canada. Based on the 18-fold symmetry of this disc-shaped fossil, we assign it to the total-group Ctenophora. Our phylogenetic analyses suggest that the new taxon Daihuoides jakobvintheri gen. et sp. nov. falls near Cambrian stem ctenophores such as 'dinomischids' and 'scleroctenophorans'. Accordingly, Daihuoides is a Lazarus-taxon, which post-dates its older relatives by over 140 million years, and overlaps temporally with modern ctenophores, whose oldest representatives are known from the Early Devonian. Our analyses also indicate that the fossil record of ctenophores does not provide strong evidence for or against the phylogenomic hypothesis that ctenophores are sister to all other metazoans.
像其他软体生物一样，栉水母（栉水母动物）只有在特殊的埋藏条件下才能产生化石。在这里，我们首次记录了来自加拿大东部米瓜莎的晚泥盆世栉水母化石。基于这个盘状化石的 18 重对称结构，我们将其归入栉水母总门。我们的系统发育分析表明，新的分类群戴氏虫（Daihuoides jakobvintheri）属和种是后生动物冠群栉水母，与寒武纪的原始栉水母（如“栉水母类”和“硬栉水母类”）关系密切。因此，戴氏虫是一个复活物种，它比其更早的亲缘物种晚出现了 1.4 亿多年，并且与现代栉水母同时存在，现代栉水母最早的代表可追溯到早泥盆世。我们的分析还表明，栉水母的化石记录并不能为栉水母是所有后生动物的姐妹群的系统基因组假说提供有力的证据。
