Melampyrum cristatum, also known as crested cow-wheat [1] is a species of flowering plant in the family Orobanchaceae.

Seeds possess soft, oily, elaiosomes, which are collected, eaten and distributed by ants.

[3][4] M. cristatum is native to the following places: Albania, Altai, Austria, the Baltic States, Belarus, Belgium, Bulgaria, Corsica, Crete, Czech Republic, Denmark, Finland, France, Germany, Great Britain, Hungary, Italy, Kazakhstan, North Caucasus, Norway, Poland, Romania, Russia, Siberia (western), Slovakia, Spain, Sweden, Switzerland, Turkey (European), Ukraine, Yugoslavia.

[1] Seeds of M. cristatum possess soft, oily, elaiosomes, which are collected and eaten by wood ants (Formica).

[6] [3] This relationship is known as mutualistic between both organisms as the ants obtain a food source, whilst seeds are distributed enabling M. cristatum it to colonize new habitats.