Japanese quail
Neuropsin and its orthologs have been found experimentally in a small number of animals, among them human, house mouse ("Mus musculus"), chicken ("Gallus gallus domesticus"), the Japanese quail ("Coturnix japonica"), the European brittle star "Amphiura filiformis" (related to starfish), the tardigrade water bear ("Hypsibius dujardini"), and the tadpole of "Xenopus laevis".