The present invention provides a heterocyclic compound that exhibits superior control effect aganist harmful arthropods and that is represented by formula (I): (I) [in the formula, Q 1 represents an oxygen atom or the like； Q 2 represents an oxygen atom or the like； T represents a C1-C10 chain hydrocarbon group or the like； A 1 represents a nitrogen atom or the like； A 2 represents a nitrogen atom or the like； A 3 represents a nitrogen atom or the like； A 4 represents a nitrogen atom or the like； R 2 represents a cyclopropyl group or the like； R 3 represents a C1-C6 chain hydrocarbon groupor the like； n is 1 or 2； and q is 0, 1, 2 or 3], and also provides a composition containing said compound and one or more types of components selected from a group including a group (a), a group (b), a group (c), and a group (d) described in the Description.
