Heteroxeny

Not to be confused with the Heteroxenia genus of corals.

Heteroxeny, or heteroxenous development, characterizes a parasite whose development involves several host species.^[1] Heteroxeny has been used as the basis for splitting genera.^[2]

A dixenous life cycle: the apicomplexan parasitic protist Babesia microti and its two different taxonomic hosts, the deer tick and the white-footed mouse.

When there are two or three hosts, the development cycle is named diheteroxenous or triheteroxenous, respectively. More ambiguously, these terms are sometimes synonymized as dixenous or trixenous.^[1]

The etymology of the terms heteroxeny / heteroxenous derives from the two ancient Greek words ἕτερος (héteros), meaning "other, another, different", and ξένος (xénos), meaning "foreign".^[3][4]

In mycology, the term heteroecious has also been used for parasitic fungi with multiple hosts, and the terms can be used synonymously.^[5]