Work

A Review of Onychophoran Phylogenic Studies Reveals Resilience of Soil Ecosystems to the Chicxulub Impact Event

Year: 2025

Type: article

Abstract: Onychophora (velvet worms) are rare, soil-dwelling invertebrates with a fragile body structure that limits their fossil record. Their current distribution across the Neotropics has long been shaped by vicariance and dispersal events. Here, we evaluate the hypothesis that the Cretaceous–Paleogene (K–Pg) asteroid impact played a role in shaping the modern biogeography of Onychophora by eliminating lineages within the affected zone. Using published molecular phylogenies and geological data on the Chicxulub impact, we assess whether extant clades are congruent with a post-impact recolonization scenario. We find that several clades have divergence dates incompatible with extinction at the K–Pg boundary and that current distributions do not show a clear biogeographic signature consistent with impact-induced extirpation. Our hypothesis test supports the survival of onychophoran lineages through the K–Pg event and calls for caution in attributing modern distributions to a single extinction event without integrating molecular, stratigraphic, and ecological data.

Source: Fossil Studies

DOI: 10.3390/fossils3040014

Authors: Julián Monge-Nájera, Yostin Añino

Institutions: Universidad de Panamá, Distance State University

Language: English

Topic: Evolution and Paleontology Studies

Subfield: Paleontology

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Life on land

Open Access status: gold

Estimated APC paid: $1,207