botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...

, an obconic is an inverted cone shape. The term is most frequently applied to certain fruit or

hypanthium In angiosperms, a hypanthium or floral cup is a structure where basal portions of the calyx, the corolla, and the stamens form a cup-shaped tube. It is sometimes called a floral tube, a term that is also used for corolla tube and calyx tube. It ...

structures with the apical end attached to the stem; however, less frequently the usage may apply to the

pistil Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' ...

structure. In the case of

fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

the designation is often made to the

ascospore An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or s ...

. The use of ''obconic'' in botany dates to at least as early as the nineteenth century; however, some modern usage applies to an entire plant form, such as the shape of a whole shrub. More broadly, in geometry or design, the term can be assigned in an abstract manner to shapes in the natural or man-made world which show an inverted cone design.

Botanical examples

The

carnivorous plant Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryot ...

'' Nepenthes deaniana'' has pitcher elements that are obconic in shape to capture insects. The

of the western USA plant ''

Heuchera rubescens ''Heuchera rubescens'', with the common name pink alumroot, is a species of ''Heuchera''. The small perennial plant is native to the Western United States and northern Mexico Mexico (Spanish: México), officially the United Mexican States ...

'' has one

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

with an obconic structure, while several other subspecies have alternative hypantium geometries, so that the obconic characteristic is a subspecies determinant and diagnostic. The

of the Toyon shrub is also generally obconic in shape. The

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

n tree '' Eriobotrya latifolia'' and several other species within the genus '' Eriobotrya'' have an obconic

calyx Calyx or calyce (plural "calyces"), from the Latin ''calix'' which itself comes from the Ancient Greek ''κάλυξ'' (''kálux'') meaning "husk" or "pod", may refer to: Biology * Calyx (anatomy), collective name for several cup-like structures ...

, although some individuals manifest

clavate This glossary of entomology describes terms used in the formal study of insect species by entomologists. A–C A synthetic chlorinated hydrocarbon insecticide, toxic to vertebrates. Though i ...

calices. The basal portion of the pistil of '' Pachypodium baronii exhibits the obconic structural design. As a fungal example the species ''

Pocillum ''Pocillum'' is a genus of fungi in the family Helotiaceae The Helotiaceae are a family of fungi in the order Helotiales. The distribution of species in the family are widespread, and typically found in tropical areas. There are 117 genera an ...

cesatii'' is noted to have an obconic ascospore.

Etymology and historical usage

The derivation of the word ''obconic'' is based upon the Greek with the common prefix ''ob'', meaning ''inverted'', and the Greek word for angle ''gon'' or ''gonia'', followed by the generic suffix ''ic''.Laurence Urdang, Alexander Humez and Howard G. Zettler (1982) ''Suffixes and Other Word-final Elements of English'', Contributor Laurence Urdang, Published by Gale Research Co. Historically botanists have used the designation ''obconic'' to describe elements of a plant such as the fruit, hypanthium, calyx or pistil base since at least as early as the nineteenth century, and in modern times the term has been generalized to also refer to an entire plant architectural shape.

References

{{botany-stub Plant morphology Geometric shapes

Botanical examples

Etymology and historical usage

See also

References