Bidens

Taxobox
name = "Bidens"


image_width = 250px
image_caption = Smooth Beggarticks ("Bidens laevis") being pollinated by a bombyliid fly
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
subclassis = Asteridae
unranked_ordo = Euasterids I
ordo = Asterales
familia = Asteraceae
subfamilia = Asteroideae
tribus = Heliantheae
subtribus = Coreopsidinae
genus = "Bidens"
genus_authority = L.
subdivision_ranks = Species
subdivision = Many, see text.
synonyms ="Campylotheca" Cass.

"Bidens" is a genus in the family Asteraceae. It contains about 200 species. The common names beggarticks, bur-marigolds, stickseeds, tickseeds and tickseed sunflowers refer to the achene burrs on the seeds of this genus, most of which are barbed. The generic name refers the same fact; it means "two-tooth", from Latin "bis" "two" + "dens" "tooth".

The plants 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.

Smooth Beggarticks ("B. laevis") is a common fall flower in the southeastern USA. Pitchfork Weed ("B. frondosa") is considered to be a weed in New Zealand, although it is not officially declared an invasive species.

On the Hawaiian Islands, "Bidens" are called "kokoʻolau" or "koʻokoʻolau" [Carr (2006)] . They were and still are used to brew a refreshing tea. In some regions, leaves of Hairy Beggarticks ("B. pilosa") and Three-lobed Beggarticks ("B. tripartita") are sometimes eaten as a vegetable.

Nodding Beggarticks ("B. cernua") and Hairy Beggarticks are useful as honey plants. Several "Bidens" species are used as food by the caterpillars of certain Lepidoptera, such as the noctuid moth "Hypercompe hambletoni" and the Painted Lady ("Vanessa cardui", a brush-footed butterfly). The plant pathogen Bidens mottle virus was named after the present genus, as it was first isolated from Hairy Beggarticks; it infects a wide range of Asteraceae and other plants.

elected species

* "Bidens alba" (L.) DC.Verify source|date=November 2007 – Romerillo
* "Bidens amplectens" – Waiʻanae Kokoʻolau
* "Bidens amplissima" Greene – Vancouver Island Beggarticks
* "Bidens aristosa" (Michx.) Britt. – Bearded Beggarticks, Long-bracted Beggarticks, Tickseed Beggarticks, Western Tickseed
* "Bidens asymmetrica" (Levl.) Sherff – Koʻolau Kokoʻolau
* "Bidens aurea" (Ait.) Sherff – Arizona Beggarticks
* "Bidens bidentoides" (Nutt.) Britt. – Delmarva Beggarticks
* "Bidens bigelovii" Gray – Bigelow's Beggarticks
* "Bidens bipinnata" L. – Spanish Needles
* "Bidens campylotheca" – Viper Beggarticks
* "Bidens cernua" L. (syn. "B. glaucescens" Greene) – Nodding Beggarticks, Nodding Bur-marigold
* "Bidens cervicata" Sherff – Kauaʻi Beggarticks
* "Bidens conjuncta" – Bog Beggarticks
* "Bidens connata" Muhl. ex Willd. – Purple-stemmed Beggarticks, Purple-stemmed Swamp Beggarticks, Connate Beggarticks, London Bur-marigold, Southern Tickseed
* "Bidens coronata" (L.) Britt. – Crowned Beggarticks
* "Bidens cosmoides" – Cosmosflower Beggarticks, "poʻola nui"
* "Bidens cuneata" Sherff – Cuneate Bidens, Wedge Beggarticks
* "Bidens cynapiifolia" Kunth – West Indian Beggarticks
* "Bidens discoidea" (Torr. & Gray) Britt. – Discoid BeggarticksVerify source|date=November 2007 , Small Beggarticks, Swamp Beggarticks, Few-bracted Beggarticks
* "Bidens eatonii" Fern. – Eaton's Beggarticks
* "Bidens ferulifolia" (Jacq.) DC. – Apache Beggarticks, Fern-leaved Beggarticks
* "Bidens forbesii" Sherff – Coastalbluff Beggarticks
* "Bidens frondosa" – Devil's Beggarticks, Large-leaved Beggarticks, Common Beggarticks, Common Tickseed, Devil's Bootjack, Devil's Pitchfork, Pitchfork Weed
* "Bidens gardneri" Baker – Ridge Beggarticks
* "Bidens hawaiensis" Gray – Hawaiʻi Beggarticks
* "Bidens heterodoxa" (Fern.) Fern. & St. John – Connecticut Beggarticks
* "Bidens heterosperma" Gray – Rocky Mountain Beggarticks
* "Bidens hillebrandiana" (Drake) O. Deg. – Seacliff Beggarticks
* "Bidens hyperborea" Greene – Estuary Beggarticks, Coastal Beggarticks, Northern Estuarine Beggarticks, Seacliff Beggarticks
* "Bidens laevis" (L.) B.S.P. – Smooth Beggarticks, Smooth Bur-marigold, Larger Bur-marigold
* "Bidens lemmonii" Gray – Lemmon's Beggarticks
* "Bidens leptocephala" Sherff – Few-flowered Beggarticks
* "Bidens macrocarpa" (Gray) Sherff – Large-fruited Beggarticks
* "Bidens mannii"
* "Bidens mauiensis" (Gray) Sherff – Maui Beggarticks
* "Bidens menziesii" (Gray) Sherff – Mauna Loa Beggarticks
* "Bidens micrantha" Gaud. – Grassland Beggarticks
** "Bidens micrantha" ssp. "kalealaha" – Kalealaha Beggarticks
* "Bidens mitis" (Michx.) Sherff – Small-fruited Beggarticks
* "Bidens molokaiensis" – Molokaʻi Beggarticks
* "Bidens × multiceps" Fassett
* "Bidens pilosa" – Hairy Beggarticks
* "Bidens polylepis" Blake – Awnless Beggarticks
* "Bidens populifolia" – Oʻahu Beggarticks, Poplar-leaved Bidens
* "Bidens reptans" (L.) G. Don – Manzanilla Trepador
* "Bidens sandvicensis" Less. – Shrubland Beggarticks
* "Bidens schimperi" Sch. Bip.
* "Bidens simplicifolia"
* "Bidens socorrensis"
* "Bidens squarrosa" Kunth
* "Bidens tenuisecta" Gray – Slim-lobed Beggarticks
* "Bidens torta" Sherff – Corkscrew Beggarticks
* "Bidens tripartita" (syn "B. acuta, B. comosa") – Three-lobed Beggarticks, Three-part Beggarticks, Leafy-bracted Beggarticks, Trifid Bur-marigold
* "Bidens triplinervia"
** "Bidens triplinervia" var. "macrantha"
* "Bidens valida" Sherff – Kahili Beggarticks
* "Bidens vulgata" Greene – Big Devil's Beggarticks, Tall Beggarticks, Tall Bur-marigold, Western Sticktight
* "Bidens wiebkei" – Wiebke's Beggarticks, Molokaʻi Koʻokoʻolau

Footnotes

References

* (2006): [http://www.botany.hawaii.edu/Faculty/Carr/bidens.htm Hawaiian Native Plant Genera - Asteraceae - "Bidens"] . Version of 2006-MAR-29. Retrieved 2007-NOV-14.

* ISBN 0-89672-614-2 (Book)