''Chondrilla'' is a genus of flowering plants in 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 ...

. They are native to Eurasia, and certain taxa are known as

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...

outside their native range.''Chondrilla''.
Flora of North America. The best known of these is rush skeletonweed (''Chondrilla juncea''), a

noxious weed A noxious weed, harmful weed or injurious weed is a weed that has been designated by an agricultural or other governing authority as a plant that is harmful to agricultural or horticultural crops, natural habitats or ecosystems, or humans or lives ...

established in Africa, Australia, and the Americas. ''Chondrilla'' species produce one or more stems up to 1.5 meters tall from a

taproot A taproot is a large, central, and dominant root from which other roots sprout laterally. Typically a taproot is somewhat straight and very thick, is tapering in shape, and grows directly downward. In some plants, such as the carrot, the taproot ...

which can be very deep and highly branched. The basal and lower stem leaves are divided and toothed, and are borne on winged petioles. The upper leaf blades are smaller and simple. The cylindrical

flower heads A pseudanthium (; : pseudanthia) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers ...

are often solitary but may grow in clusters, and are located along the branches and at the ends. They contain several yellow florets that soon wither. The fruit is a cylindrical, beaked, ribbed cypsela with a pappus of many white bristles. This genus is closely related to the

dandelions ''Taraxacum'' () is a genus of flowering plants in the family Asteraceae, which consists of species commonly known as dandelions. The scientific and hobby study of the genus is known as taraxacology. The genus has a near-cosmopolitan distribu ...

of genus ''Taraxacum''. Plants of both genera undergo

apomixis In botany, apomixis is asexual development of seed or embryo without fertilization. However, other definitions include replacement of the seed by a plantlet or replacement of the flower by bulbils. Apomictically produced offspring are geneti ...

, producing fertile seeds via

asexual reproduction Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the f ...

.Van Dijk, P. J. (2003)
Ecological and evolutionary opportunities of apomixis: insights from ''Taraxacum'' and ''Chondrilla''.
''Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences'' 358(1434), 1113-21. Confusingly, the name '' Chondrilla'' is shared by a genus of

Demosponge Demosponges or common sponges are sponges of the class Demospongiae (from + ), the most diverse group in the phylum Porifera which include greater than 90% of all extant sponges with nearly 8,800 species A species () is often de ...

. ; Species''Chondrilla''.
The Plant List.

References

* * Asteraceae genera Cichorieae {{Cichorieae-stub