FutureStarr

Asclepias Eastwoodianaor

Asclepias Eastwoodianaor

Asclepias Eastwoodiana

 

Members of the genus Asclepias produce some of the most complex flowers in the plant kingdom, comparable to orchids in complexity. Five petals reflex backwards revealing a gynostegium surrounded by a five-membrane corona. The corona is composed of a five-paired hood-and-horn structure with the hood acting as a sheath for the inner horn. Glands holding pollinia are found between the hoods. The size, shape and color of the horns and hoods are often important identifying characteristics for species in the genus Asclepias.

Asclepias

Agrawal, Anurag A.; Fishbein, Mark; (ORCID 0000-0003-3099-4387 GS 80G72B0AAAAJ) (2008-07-22). "Phylogenetic escalation and decline of plant defense strategies". Proceedings of the National Academy of Sciences. 105 (29): 10057–10060. Bibcode:2008PNAS..10510057A. doi:10.1073/pnas.0802368105. ISSN 0027-8424. PMC 2481309. PMID 18645183.Pollination in this genus is accomplished in an unusual manner. Pollen is grouped into complex structures called pollinia (or "pollen sacs"), rather than being individual grains or tetrads, as is typical for most plants. The feet or mouthparts of flower-visiting insects such as bees, wasps and butterflies, slip into one of the five slits in each flower formed by adjacent anthers. The bases of the pollinia then mechanically attach to the insect, so that a pair of pollen sacs can be pulled free when the pollinator flies off, assuming the insect is large enough to produce the necessary pulling force (if not, the insect may become trapped and die).

Members of the genus Asclepias produce some of the most complex flowers in the plant kingdom, comparable to orchids in complexity. Five petals reflex backwards revealing a gynostegium surrounded by a five-membrane corona. The corona is composed of a five-paired hood-and-horn structure with the hood acting as a sheath for the inner horn. Glands holding pollinia are found between the hoods. The size, shape and color of the horns and hoods are often important identifying characteristics for species in the genus Asclepias. Other: The genus name, “Asclepias”, refers to “Asklepios”, a Greek physician and an authority on the medicinal use of plants and who according to Greek Myth could bring the dead to life. Hades fearing a loss of employment, convinced his brother Zeus to kill Asklepios with a bolt of lightning. The species name, “macrosperma”, means “large seed” and refers to the pod and the seeds. (Source: www.nps.gov)

 

Related Articles