Small round leaved orchid

Description

Platanthera orbiculata, the round leaved orchid or lesser roundleaved orchid, is a species of orchid native to forested areas of North America. It is widespread across most of Canada and parts of the United States (Alaska, New England, Appalachian Mountains, Great Lakes Region, Rocky Mountains, Black Hills and northern Cascades). The genus Platanthera belongs to the subfamily Orchidoideae of the family Orchidaceae, and comprises about 150 species of orchids. The members of this genus, known as the butterfly orchids or fringed orchids, were previously included in the genus Orchis, which is a close relative (along with the genus Habenaria). They are distributed throughout the temperate regions of the Northern Hemisphere. They are terrestrial and have tubercules. Louis Claude Richard chose the name Platanthera for this genus; it comes from the Greek and means "broad or wide anther," referring to the separation of the base of the pollinia in the type species of the genus. Richard felt that this characteristic distinguished the genus Platanthera from both the genus Orchis and the genus Habenaria. However, today the defining characteristics of the genus are generally accepted to be the absence of both stigmatic processes (typical in Habenaria) and ovoid root-tuberoids (characteristic of both Habenaria and Orchis). Still, P. nivea, P. clavellata and P. integra all have stigmatic processes, showing the limitations of morphological characteristics in defining this clade.