Constraining the Deep Origin of Parasitic Flatworms and Host-Interactions with Fossil Evidence

Kenneth de Baets (1) , Paula Dentzien-Dias (2) , Ieva Upeniece (3) , Olivier Verneau (4, 5) , Philip C.J. Donoghue (6)

1 Fachgruppe PaläoUmwelt
2 Núcleo de Oceanografia Geológica
3 Department of Geology
4 Unit for Environmental Sciences and Management
5 CEFREM - Centre de Formation et de Recherche sur les Environnements Méditérranéens
6 School of Earth Sciences [Bristol]

Novel fossil discoveries have contributed to our understanding of the evolutionary appearance of parasitism in flatworms. Furthermore, genetic analyses with greater coverage have shifted our views on the coevolution of parasitic flatworms and their hosts. The putative record of parasitic flatworms is consistent with extant host associations and so can be used to put constraints on the evolutionary origin of the parasites themselves. The future lies in new molecular clock analyses combined with additional discoveries of exceptionally preserved flatworms associated with hosts and coprolites. Besides direct evidence, the host fossil record and biogeography have the potential to constrain their evolutionary history, albeit with caution needed to avoid circularity, and a need for calibrations to be implemented in the most conservative way. This might result in imprecise, but accurate divergence estimates for the evolution of parasitic flatworms.

Keywords: Calibration; Cestoda; Coevolution; Coprolite; Evolutionary history; Fossil record; Molecular clock; Mollusca; Monogenea; Neodermata; Pathology; Platyhelminthes; Platyzoa; Trematoda; Vertebrates

Domains: Parasitology; Populations and Evolution [q-bio.PE]; Paleontology

Kenneth de Baets, Paula Dentzien-Dias, Ieva Upeniece, Olivier Verneau, Philip C.J. Donoghue. Constraining the Deep Origin of Parasitic Flatworms and Host-Interactions with Fossil Evidence. Advances in Parasitology, 2015, Fossil Parasites, 90, pp.93-135. ⟨10.1016/bs.apar.2015.06.002⟩. ⟨hal-01257074⟩