''Glaucidium'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of plants in

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Ranunculaceae Ranunculaceae (, buttercup or crowfoot family; Latin "little frog", from "frog") is a family (biology), family of over 2,000 known species of flowering plants in 43 genera, distributed worldwide. The largest genera are ''Ranunculus'' (600 spec ...

, comprising a single species ''Glaucidium palmatum'' (Japanese wood poppy; シラネアオイ ''Shirane-aoi''). It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to northern and eastern

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

Hokkaidō is the second-largest island of Japan and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by railway via the Seikan Tunnel. The ...

and northeastern

Honshū , historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the seventh-largest island in the world, and the second-most populous after the Indonesian ...

on mountains close to the

Sea of Japan The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it ...

.Shiro Tsuyuzaki, Hokkaido University
Japanese Wood Poppy
Germplasm Resources Information Network
''Glaucidium''
It is a

rhizomatous In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of ...

perennial plant In horticulture, the term perennial (''wikt:per-#Prefix, per-'' + ''wikt:-ennial#Suffix, -ennial'', "through the year") is used to differentiate a plant from shorter-lived annual plant, annuals and biennial plant, biennials. It has thus been d ...

growing to 40 cm tall with a rigid stem with two large (20 cm diameter) palmately lobed leaves at the top and small membraneous leaves lower on the stem. The flower is produced singly at the top of the stem, 8 cm in diameter, with four pink to pale purple (rarely white) petaloid sepals, numerous stamens and two carpels. The fruit is a cluster of follicles.Huxley, A., ed. (1992). ''New RHS Dictionary of Gardening''. Macmillan . It is sometimes placed in its own family Glaucidiaceae, or in the past in the family

Paeoniaceae The peony or paeony () is any flowering plant in the genus ''Paeonia'', the only genus in the family Paeoniaceae. Peonies are native to Asia, Europe, and Western North America. Scientists differ on the number of species that can be distinguishe ...

. Paeoniaceae, however, has now been shown unequivocally to belong in

Saxifragales Saxifragales is an order (biology), order of flowering plants in the Superrosids, superrosid clade of the eudicots. It contains 15 Families (biology), families and around 100 genera, with nearly 2,500 species. Well-known and economically import ...

, while ''Glaucidium'' is firmly in the family

. In cultivation, ''Glaucidium palmatum'' prefers a cool, moist, sheltered position in partial shade.

References

{{Taxonbar, from1=Q135626, from2=Q15102091, from3=Q21229522 Ranunculaceae Endemic flora of Japan Plants described in 1845 Taxa named by Philipp Franz von Siebold Taxa named by Joseph Gerhard Zuccarini