Some similarities to : Atlas Poppy, which also has yellowish-orange flowers but that has long leaves with triangular lobes.

Slight resemblance to : Yellow Horned-Poppy which also has yellow flowers but that grows by the seaside and has massively long seed capsules, curling out over a foot, and to Greater Celandine but that has glaucous-green rounded-lobed leaves and exudes an orange liquid if the stems are broken.

Has a hollow stem but without the milky latex of the Papaver or Glaucium poppies. The only plant in this Genus, Meconopsis, at least in Eorope (but other species exist from China and the Himalayas). It is planted extensively in gardens from where it readily spreads. It has pinnately divided leaves and mostly yellow flowers, but orange flowers are quite common.

Meconic Acid is present at about 5% in several species of Poppy, including Opium Poppy and Welsh Poppy (Meconopsis Cambrica) from which it derives its name. It is pharmacologically inert, having little or no effect. It forms salts called Meconates with metals and alkaloids. It is chemically similar to the Chelidonic Acid present in Greater Celandine, which also belongs to the Poppy Family.

BENZYLISOQUINOLINE ALKALOIDS in WELSH POPPY The major alkaloids of Welsh Poppy are (-)-Mecambrine, (-)-Mecambridine, (-)-Flavinantine, (+)-Magnoflorine, and a small amount of (+)-Mecambroline. Mecambroline (aka Isofugapavine and Isofungipavine), named after its occurrence in Welsh Poppy has a greater abundance within it than does Magnofluorine, a similar compound. It has the aporphine skeleton. Mecambrine is a spiro-compound with the proaporphine skeleton which is dissimilar to the spiro compound Fumaricine which occurs in some Fumaria Genus species. Mecambridine is an benzylisoquinoline with the same skeleton as Berberine. All the above benzylisoquinolines are named after Welsh poppy in which they were first discovered. Reticuline, however, is a benzylisoquinoline based upon the Morphine skeleton. The production of morphinan alkaloids in the plant was found to be stimulated by Tyrosine and Ascorbic Acid. Minor alkaloids found within Welsh poppy include Roemarine, Corytuberine. Minute quantities of Protopine, AlloCryptopine, Roemeroline, Papaverrubine D and C, Berberine, Coptisine, Corysamine and Palmatine were also found, all typical of plants of the Poppy Family (Papapaveraceae).