epimorfen

Epimorfen is a term used in biology to denote organisms or tissues that regenerate through epimorphy, a form of regeneration driven by the growth of a proliferative blastema. The term epimorfen is the Dutch plural form of epimorph and appears in some Dutch-language literature. In English-language texts, the singular epimorph and plural epimorphs are more common.

Epimorphy involves the formation of a blastema from dedifferentiated or progenitor cells at the site of injury, followed by cell proliferation and redifferentiation to reconstruct lost structures. This contrasts with morphallaxis, where regeneration occurs largely through remodeling of existing tissues with little cell proliferation, and with morphogenesis-based regeneration in which existing tissues reorganize.

Organisms showing epimorphic regeneration include many amphibians, notably salamanders such as newts and axolotls, which can regrow limbs, tails, and repair complex tissues. Some reptiles, e.g., certain lizards, also regenerate tails epimorphically under hormonal and environmental conditions. Among invertebrates, epimorphic processes are described in various crustaceans and other taxa, but the exact mechanisms and nomenclature vary by group.

In modern regeneration research, the distinction between epimorphic, morphallactic, and histogenetic regeneration remains a framework for comparing strategies, with ongoing work detailing molecular signals, stem cell dynamics, and tissue context that govern blastema formation and organ reconstitution.

See also epimorph, morphallaxis, blastema.