Because he had redefined Ornithomimosauria in a much narrower sense, a new term was made necessary within his preferred terminology to denote the clade containing the sistergroups Ornithomimosauria and Alvarezsauridae — previously the latter had been contained within the former.
Budući da je on definirao Ornithomimosauria u mnogo užem smislu, nastala je potreba za novim pojmom unutar njegove preferirane terminologije kako bi se naznačio kladus koji sadrži sestrinske grupe od skupina Ornithomimosauria i Alvarezsauridae; ova zadnja se prije nalazila unutar prve.