Papaver /pəˈpeɪvər/[2] is a genus of 70–100 species of frost-tolerant annuals, biennials, and perennials native to temperate and cold regions of Eurasia, Africa and North America.

The flowers have two sepals that fall off as the bud opens, and four (or up to six) petals in red, pink, orange, yellow, or lilac.

The opened capsule scatters its numerous, tiny seeds as air movement shakes it, due to the long stem.

Argemonidium includes four annual, half-rosette species, P. argemone, P. pavonium, P. apulum, and P. hybridum (Kadereit 1986a).

Papaver apulum, P. argemone and P. pavonium occur allopatrically from the Adriatic Sea to the Himalayan range.

[6] These species are easily distinguished in petal and capsule characters,[6] but are clearly closely related according to molecular analysis.

[8] They share some morphological characters that distinguish them from Papaver, including polyporate pollen grains, and long internodes superior the basal leaf rosette.

Meconella is widely distributed, with populations spanning central, inner and eastern Asia, Siberia, Scandinavia, northern Greenland, Canada, the Rocky Mountains, and regions of Europe.

[9] It has been distinguished from other Papaver sections morphologically by its bristly, valvate capsules, pinnatisect leaves, pale stamen, and white, orange or yellow corolla.

[8] The results of the Carolan et al. (2006) analysis present a major problem to previous taxonomy of the genera Meconopsis, and Papaver.

Horrida is represented by a single species Papaver aculeatum of, an annual flower native to South Africa.

The vegetative parts are covered with setae, and the growth form is a rosette with rarely branching axes, and narrowly elliptical incised leaves.

Horrida and Pilosa have racemose inflorescences, pale filiform filaments and long capsules with flat stigmatic discs, while P. californicum and sect.

Meconidium share valvate capsule dehiscence and pale filaments, but geographically these species are distinct, and do not follow molecular evidence.

In Carolan et al.’s (2006) combined ITS, trnL-F trees, both Horrida and Californicum attach to basal nodes within the main clade Papaver.

Kadereit et al. (1997) postulated that Stylomecon heterophylla arose from within Papaver and should not be relegated as a separate genus.

In fact, it forms a well-supported sister-group to the core sections of Papaver, excluding Argemonidium, Californicum, Horrida and Meconella.

have a subscapose growth habit, and their distribution includes south-western Asia, northern Africa and southern Spain.

Carolan et al. (2006) demonstrated that several species with this trait however are closely related to taxa possessing a style e.g. S. heterophylla and P. californicum, and P. sect.

Papaver has long been considered the most derived clade within Papaveroideae, due to the belief that the stigmatic disc was an apomorphous characteristic.

Sections Meconella and Californicum exhibit valvate dehiscence, and their basal position within Papaver suggest this may be an ancestral form.

The alkaloid rhoeadine, derived from the flowers of the corn poppy (Papaver rhoeas), is used as a mild sedative.

The ancient Greeks portrayed Hypnos, Nyx and Thanatos, the gods of sleep, night and death, with the symbol of the poppy.

Pliny the Elder, a Roman historian, later mentioned an “intermediate” type between the wild and cultivated poppy, likely Papaver rhoeas.

[4] Today, morphine and codeine are common alkaloids found in several poppy varieties, and are important drugs for much of the world.

Today, the law and its enforcement remain vague and controversial, even inciting episodes between gardeners and "the poppy police".