Heliotropium

Heliotropes
Heliotropium peruvianum
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	(unplaced)
Family:	Boraginaceae
Subfamily:	Heliotropioideae
Genus:	Heliotropium L.
Species
250-300, see text

Heliotropium (pronounced /ˌhiːli.ɵˈtroʊpi.əm/)^[1] is a genus of flowering plants in the borage family, Boraginaceae. There are 250 to 300 species in this genus, which are commonly known as heliotropes (sg. /ˈhiːli.ətroʊp/).

The name "heliotrope" derives from the fact that these plants turn their leaves to the sun. Helios is Greek for "sun", tropein means "to turn". The old English name "turnsole" has the same etymology.

Ecology and human use

Grey leaf heliotrope Heliotropium ovalifolium at Pocharam lake, Andhra Pradesh, India.

Danainae butterflies like to visit these plants. One reason is to drink the sap which renders the butterflies noxious to predators. Some species collect olfactory compounds to produce a kind of "perfume" to attract mates. Caterpillars of the Grass Jewel (Freyeria trochylus), a gossamer-winged butterfly, feed on H. strigosum.

Several heliotropes are popular garden plants, most notably Garden Heliotrope (H. arborescens). Some species are weeds and many are hepatotoxic if eaten in large quantities due to abundant pyrrolizidine alkaloids. The sap of heliotrope flowers, namely of European Heliotrope (H. europaeum), was used as a food coloring in Middle Ages and Early Modern French cuisine.

One of the most famous ragtime piano melodies is Heliotrope Bouquet, composed in 1907 by Louis Chauvin (the first two strains) and Scott Joplin (the last two strains).

Common heliotrope is grown in Southern Europe as an ingredient for perfume.^[2]

Selected species

Heliotropium anomalum var. argenteum

European Heliotrope (Heliotropium europaeum)

Indian Turnsole (Heliotropium indicum) inflorescence

Heliotropium procumbens habitus

Heliotropium strigosum in Keesara, Rangareddy district, Andhra Pradesh, India.

• Heliotropium amplexicaule – Clasping Heliotrope, Summer Heliotrope, Blue Heliotrope
• Heliotropium anderssonii
• Heliotropium anomalum Hook. & Arn. – Polynesian Heliotrope, Pacific Heliotrope (Pacific Islands)
  • Heliotropium anomalum var. argenteum – Hinahina kū kahakai (Hawaiʻi)
• Heliotropium arborescens – Garden Heliotrope, Common Heliotrope, "cherry pie"
• Heliotropium argenteum
• Heliotropium asperrimum R.Br.
• Heliotropium balfourii
• Heliotropium bracteatum R.Br.
• Heliotropium conocarpum F.Muell. ex Benth.
• Heliotropium crispatum F.Muell. ex Benth.
• Heliotropium diversifolium F.Muell. ex Benth.
• Heliotropium chenopodiaceum (A. DC.) Clos.
• Heliotropium claussenii DC.
• Heliotropium convolvulaceum – Sweet-scented Heliotrope, Showy Heliotrope
• Heliotropium curassavicum L. – Seaside Heliotrope, Salt Heliotrope, Monkey Tail, Quail Plant, "Chinese parsley"; cola de mico (Spanish)
• Heliotropium dentatum
• Heliotropium derafontense
• Heliotropium ellipticum
• Heliotropium epacrideum F.Muell. ex Benth.
• Heliotropium europaeum L. – European Heliotrope, European Turnsole (Europe, Asia, and North Africa)
• Heliotropium fasciculatum R.Br.
• Heliotropium flintii F.Muell. ex A.S.Mitch.
• Heliotropium foertherianum Diane & Hilger – Tree Heliotrope, Velvet Soldierbush, Octopus Bush (South Asia, East Asia, Melanesia, western Polynesia, northern Australia)
• Heliotropium foliatum R.Br.
• Heliotropium glabellum R.Br.
• Heliotropium heteranthum (F.Muell.) Ewart & O.B.Davies
• Heliotropium indicum – Indian Turnsole
• Heliotropium kuriense
• Heliotropium laceolatum Loefg.
• Heliotropium lineariifolium Phil.
• Heliotropium megalanthumn I.M. Johnst.
• Heliotropium nigricans
• Heliotropium paniculatum R.Br.
• Heliotropium pannifolium – St. Helena Heliotrope (Saint Helena) (extinct, c.1820)
• Heliotropium pauciflorum R.Br.
• Heliotropium paulayanum
• Heliotropium peruvianum
• Heliotropium pleiopterum F.Muell.
• Heliotropium procumbens
• Heliotropium prostratum R.Br.
• Heliotropium riebeckii
• Heliotropium shoabense
• Heliotropium sinuatum (Miers) I.M.Johnst.
• Heliotropium socotranum
• Heliotropium stenophyllum
• Heliotropium strigosum Willd.
• Heliotropium tenuifolium R.Br.
• Heliotropium ventricosum R.Br.
• Heliotropium wagneri
• Heliotropium aff. wagneri (Samhah, Yemen)

Formerly included here

• Chrozophora tinctoria (as H. tricoccum)

See also

• Turnsole

References

• Everitt, J.H.; Lonard, R.L. & Little, C.R.: (2007): Weeds in South Texas and Northern Mexico. Texas Tech University Press, Lubbock. ISBN 0-89672-614-2

External links

Wikimedia Commons has media related to: Heliotropium

• A Heliotrope at Gardener's Path
• Pictures of Heliotropes at The Old House Web
• Picture of Heliotropium chenopodiaceum at Chileflora