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Updated: Jun 3, 2026

The Golden Apple Snail Pomacea canaliculata: From Zygotes to Stable Mutant Lines
Published on: December 23, 2025
Crawling through time: Transition of snails to slugs dating back to the Paleozoic, based on mitochondrial
Mónica Medina1, Shruti Lal, Yvonne Vallès
1Evolutionary Genomics, DOE Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598, USA. mmedina@ucmerced.edu
Abstract:
Sea slugs (Gastropoda: Opisthobranchia) are characterized by extensive morphological homoplasy. In particular, reduced or absent shells are predominant throughout the group. This trend towards shell loss has resulted in a poor fossil record. DNA-based phylogenies have been helpful in improving our understanding of the evolution of this group and major clades are emerging. We report 13 new complete opisthobranch mitochondrial genomes that provide robust support for some of these emerging nodes. We name three new clades within the Opisthobranchia, the Actopleura (Acteonoidea plus Nudipleura), Placoesophaga (Cephalaspidea plus Anaspidea), and Siphoglossa (Sacoglossa plus the Siphonaria). Finally we use molecular clock dating that suggests an earlier opisthobranch divergence than previously reported. The implications of this evolutionary scenario are discussed.
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