Bidens is a
genus of
flowering plants in the aster
family,
Asteraceae.[3] The genus include roughly 230 species which are distributed worldwide.[4] Despite their global distribution, the systematics and taxonomy of the genus has been described as complicated and unorganized.[4][5] The common names beggarticks, black jack, burr marigolds, cobbler's pegs, Spanish needles, stickseeds, tickseeds and tickseed sunflowers refer to the fruits of the plants, most of which are bristly and barbed. The
generic name refers to the same character; Bidens comes from the
Latinbis ("two") and dens ("tooth").[3]
Distribution
Bidens includes roughly 230 species which are distributed worldwide[4] throughout many
tropical and warm
temperate regions.[6] Species occur in the Americas, Africa, Polynesia, Europe and Asia.[7]
Phylogeny, taxonomy and diversity
Despite their global distribution, the systematics and taxonomy of the genus has been described as complicated and unorganized.[4][5] The genus include roughly 230 species.[6][8]
Bidens is closely related to the American genus Coreopsis, and the genera are sometimes difficult to tell apart; in addition, neither is
monophyletic.[9]
Propagation
Bidens are
zoochorous; their seeds will stick to clothing, fur or feathers, and be carried to new
habitat. This has enabled them to colonize a wide range, including many
oceanic islands. Some of these species occur only in a very restricted range and several are now threatened with
extinction, notably in the
Hawaiian Islands. Due to the absence of native mammals on these islands, some of the oceanic island
taxa have reduced burrs,
evolving features that seem to aid in dispersal by the wind instead.
Bidens frondosa L. – devil's beggarticks, devil's pitchfork, devil's bootjack, pitchfork weed, common beggarticks, sticktights.
Pitchfork weed (B. frondosa) is considered to be a
weed in
New Zealand.
Bidens laevis (L.) B.S.P. – smooth beggarticks, smooth bur-marigold, larger bur-marigold.
Smooth beggarticks (B. laevis) is a common fall
flower in the southeastern United States.
^"Genus: Bidens L". Germplasm Resources Information Network. United States Department of Agriculture. 2007-10-05. Archived from
the original on 2011-06-29. Retrieved 2011-02-12.
^
abcdKnope, M. L., Funk, V. A., Johnson, M. A., Wagner, W. L., Datlof, E. M., Johnson, G., ... & Carlquist, S. (2020). Dispersal and adaptive radiation of Bidens (Compositae) across the remote archipelagoes of Polynesia. Journal of Systematics and Evolution, 58(6), 805-822.
^
abGanders, F. R., Berbee, M., & Perseyedi, M. (2000). ITS base sequence phylogeny in Bidens (Asteraceae): Evidence for the continental relatives of Hawaiian and Marquesan Bidens. Systematic Botany,25(1), 122-133.
^
abBidens. New South Wales Flora Online. National Herbarium, Royal Botanic Garden, Sydney.