Comparative phylogenomics reveal complex evolution of life history strategies in a clade of bivalves with parasitic larvae (Bivalvia: Unionoida: Ambleminae)

Cladistics
By: , and 

Links

Abstract

Freshwater mussels are a species‐rich group with biodiversity patterns strongly shaped by a life history strategy that includes an obligate parasitic larval stage. In this study, we set out to reconstruct the life history evolution and systematics in a clade of freshwater mussels adapted to parasitizing a molluscivorous host fish. Anchored hybrid enrichment and ancestral character reconstruction revealed a complex pattern of life history evolution with host switching and multiple instances of convergence, including reduction in size of larvae, increased fecundity, and growth during encapsulation. Our phylogenomic analyses also recovered non‐monophyly of taxa exhibiting multiple traits used as the basis for previous taxonomic hypotheses. Taxa with axe‐head shaped glochidia were resolved as paraphyletic, but our results strongly suggest the complex morphology is an adaptation to reduce larval size, with reduction in size further accentuated in taxa previously assigned to Leptodea. To more accurately reflect the evolutionary history of this group, we make multiple systematic changes, including the description of a new genus, Atlanticoncha gen. nov., and the synonymy of the genus Leptodea under Potamilus. Our findings contribute to the growing body of literature showing that cladistic hypotheses based solely on morphological characters, including larval morphology, can be flawed in freshwater mussels.

Publication type Article
Publication Subtype Journal Article
Title Comparative phylogenomics reveal complex evolution of life history strategies in a clade of bivalves with parasitic larvae (Bivalvia: Unionoida: Ambleminae)
Series title Cladistics
DOI 10.1111/cla.12423
Volume 36
Issue 5
Year Published 2020
Language English
Publisher Wiley
Contributing office(s) Wetland and Aquatic Research Center
Description 16 p.
First page 505
Last page 520
Google Analytic Metrics Metrics page
Additional publication details