Calyceraceae is a

plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...

family in the order

Asterales Asterales ( ) is an Order (biology), order of dicotyledonous flowering plants that includes the large Family (biology), family Asteraceae (or Compositae) known for composite flowers made of Floret#floret, florets, and ten families related to th ...

. The natural distribution of the about sixty species belonging to this family is restricted to the southern half of South America. The species of the family resemble both the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

and the

Dipsacaceae The Dipsacaceae were recognized as a family (the teasel family) of the order Dipsacales containing 350 species of perennial or biennial herbs and shrubs in eleven genera. It was published by Antoine Laurent de Jussieu in his book ''Genera planta ...

Description

Calyceraceae are perennial or annual herbs. There may be a few or many branched stems that may be without hair or with soft silky hairs. The leaves may be in a rosette at the base of the stems or set alternately along the stems.

Stipule In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole (botany), petiole). They are primarily found among dicots and rare among monocots. Stipules are considered part ...

s are lacking. The blade of the leaf is

simple Simple or SIMPLE may refer to: *Simplicity, the state or quality of being simple Arts and entertainment * ''Simple'' (album), by Andy Yorke, 2008, and its title track * "Simple" (Florida Georgia Line song), 2018 * "Simple", a song by John ...

, but may be lobed to

pinnatisect The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade is divided into two or more leaflets ...

. The margin of the leaves may be entire or toothed. The inflorescences are flowerheads comparable to those in the sunflower family. They are at the top of the stems or opposite leaves, and may have a flower stem or be seated, while each flowerhead may be on its own or in a cyme. Each individual flowerhead is surrounded by an

involucre In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also look ...

, consisting of one or two rows of bracts that are often leaf-like and usually not merged. The base of the flowerhead may be

conical In geometry, a cone is a three-dimensional figure that tapers smoothly from a flat base (typically a circle) to a point not contained in the base, called the ''apex'' or '' vertex''. A cone is formed by a set of line segments, half-lines, ...

, convex or sometimes almost

spheroid A spheroid, also known as an ellipsoid of revolution or rotational ellipsoid, is a quadric surface (mathematics), surface obtained by Surface of revolution, rotating an ellipse about one of its principal axes; in other words, an ellipsoid with t ...

al. On the base of the flowerhead, at the base of each individual flower, are linear to narrowly lanceolate, green, chaffy scales (or paleae) that become woody when seeds are ripening. Each flowerhead may contain a few or up to over one hundred

hermaphrodite A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic. The individuals of many ...

or unisexual, star-symmetric or mirror-symmetric flowers. The

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

s are fused to form a funnel-shaped or sometimes cylinder-shaped corolla that is split into four to six lobes at the top. The corolla's remains stay on the top of the one-seeded dry fruit at maturity. Four or five

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s alternate with the corolla lobes. The lower third of these filaments are fused with the corolla tube, while sometimes filaments may also be attached to their neighbors. Filaments carry

nectar Nectar is a viscous, sugar-rich liquid produced by Plant, plants in glands called nectaries, either within the flowers with which it attracts pollination, pollinating animals, or by extrafloral nectaries, which provide a nutrient source to an ...

ies. The

anther The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s stand upright, with

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

freed from a slit at the top. The style is thread-like without hairs, sticking out above the corolla tube, while the stigma at its tip is club-shaped or split in two. The

ovary The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/ oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are end ...

consists of two carpels with only one

ovule In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the ''integument'', forming its outer layer, the ''nucellus'' (or remnant of the sporangium, megasporangium), ...

, which is pendulous and

anatropous This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary ...

. The fruit is an

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple fruit, simple dry fruits, dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and Dehi ...

, with a persistent calyx which may consists of spines, contains one seed that is only enclosed by a thin

pericarp Fruits are the mature ovary or ovaries of one or more flowers. They are found in three main anatomical categories: aggregate fruits, multiple fruits, and simple fruits. Fruitlike structures may develop directly from the seed itself rather th ...

and has fleshy

endosperm The endosperm is a tissue produced inside the seeds of most of the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species, which may be auxin-driven. It surrounds the Embryo#Pla ...

. The sepals may be free or fused calyx lobes, sometimes spine-like and woody on the outside. Fruits may be dispersed separately when ripe or can remain on the floral base that breaks free of the plant.

Differences with related families

Both Calyceraceae and

have their flowers set in heads with a common floral base. The bracts surrounding the flowerhead in the Calyceraceae are leaf-like while the involucral bracts in the Asteraceae differ clearly from the leaves. The anthers are free in the Calyceraceae and form a tube in the Asteraceae. The filaments in the Calyceraceae are, at least in their lower third, fused to the corolla, whereas in the Asteraceae the filaments are free or rarely connected (e.g. in '' Barnadesia''). Both Calyceraceae and

have persistent calyces, but these become lignified or spiny in Calyceraceae, but are cup-shaped or consist of a circle of hairs in the Dipsacaceae. Stamens are alternating with the corolla lobes and anthers open at their top in the Calyceraceae whereas stamens are centered on the petals and anthers open toward the middle of the flower in the Dipsacaceae.

Genera

Eight genera are accepted: *'' Acicarpha'' – 7 species, Peru and northeastern Brazil to northern Argentina *'' Anachoretes'' – 1 species, northwestern Argentina *'' Asynthema'' – 1 species, Argentina and central Chile *'' Boopis'' – 2 species, Argentina, northern Chile, and Uruguay *'' Calycera'' – 6 species, Peru and southern Brazil to southern Argentina *'' Gamocarpha'' – 13 species, Argentina and Chile *'' Leucocera'' – 7 species, Argentina and Chile *'' Moschopsis'' – 10 species, Argentina and Chile

Distribution

The majority of species in this family occur in Argentina, seven of which are

endemics 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 ...

, with the highest species density south of the tropics. ''Calycera'' (eleven species) and ''Acicarpha'' (five species) both are widespread along the Andes from northern Argentina through to the Altiplano of Peru. Most of the thirteen species of ''Boopsis'' occur in the south of Argentina and Chile but some species are found in the tropics. ''Moschopsis'' grows in the Salta Province in Argentina. ''Acicarpha tribuloides'' occurs as an introduced weed along roads in Florida.

References

{{Authority control Asterales families Flora of Southern America