Asteraceae
-
Heliantheae
-
*Tithonia
Desf. ex Juss.
Description
:
Annual herbs
Leaves
usually alternate, simple, entire or often deeply lobed
Capitula
radiate, solitary or few together; on long peduncles, thickened towards apex
Involucre
hemispherical or broadly campanulate; bracts in 2-5 rows
Receptacle
convex, paleate; paleae rigid, usually lobed, acuminate to aristate, embracing disc florets
Ray florets
neuter; corolla yellow or orange, strap-shaped; tube somewhat compressed, linear-oblong, much shorter than lamina; lamina long-lanceolate, minutely 2- or 3-lobed
Anthers
linear, obtuse or very shortly sagittate, with lanceolate appendages
Style
terete, globose at base; branches narrowly oblong, gradually widening upward to acutely triangular tips, pubescent on outer faces
Cypselas
linear-obovate, usually 4-angled
Pappus
of connate scales, sometimes with 1 or 2 awns
x = 17 (5, 8, 11) (aneuploids, polyploidy, B-chromosomes)
Nomenclature:
*Tithonia
Desf. ex Juss.
Jussieu: 189 (1789)
Phillips: 816 (1951)
Wild: 55 (1967)
Hilliard: 307 (1977)
La Duke: 478 (1982)
Karis & Ryding: 605 (1994)
Distribution & Notes:
Global
: Species 11, SW United States to Costa Rica
Southern Africa
: Species 2: *
Tithonia diversifolia
(Hemsl.) A.Gray, Northern Province, Mpumalanga, Swaziland, KwaZulu-Natal, and *
T. rotundifolia
(Mill.) Blake, Botswana, Northern Province, North-West, Gauteng, Mpumalanga, Swaziland and KwaZulu-Natal, introduced from America, now naturalised
References:
HILLIARD, O.M. 1977.
Compositae
in Natal
. University of Natal Press, Pietermaritzburg
JUSSIEU, A.L. DE. 1789.
Genera plantarum
. Herissant & Barrois, Paris
KARIS, P.O. & RYDING, O. 1994. Tribes
Helenieae
and
Heliantheae
. In K. Bremer,
Asteraceae
, cladistics and classification
. Timber Press, Portland, Oregon
LA DUKE, J.C. 1982. Revision of
Tithonia
.
Rhodora
84
PHILLIPS, E.P. 1951. The genera of South African flowering plants, edn 2.
Memoirs of the Botanical Survey of South Africa
No. 25
WILD, H. 1967. The
Compositae
of the Flora zambesiaca area, 1.
Kirkia
6
Copyright of the content hosted by this website remains with the
South African National Biodiversity Institute
(SANBI), unless stated otherwise.
Material from this site may be used in other media, provided that SANBI is acknowledged by the name
South African National Biodiversity Institute
(SANBI) or refer to the '
How to cite this resource
' paragraph on the Home page.
Liability disclaimer: Visitors use this site at their own risk and SANBI is not liable for any of the consequences resulting therefrom.
Welcome to Biodiversity Advisor 2.0!
Biodiversity Advisor, developed by the South African National Biodiversity Institute (SANBI) and its Data Partners, is a system that will provide integrated biodiversity information to a wide range of users who will have access to geospatial data, plant and animal species distribution data, ecosystem-level data, literature, images and metadata.
The integrated information comes from our much-loved Botanical Database of Southern Africa (BODATSA) also known as Plants of Southern Africa (POSA), Zoological Database of Southern Africa (ZODATSA), Biodiversity Geographic Information System (BGIS), SANBI's institutional repository (Opus) and others.
The system is still under development, so you may find a few bugs/issues. If you do, please report it via the error reporting button available in various sections of the website or provide us with any useful feedback you may have via the ‘Give us feedback’ option available in the sidebar menu. You can create a free account for yourself by clicking on the user profile icon which will take you through to the login page. Here you can choose the ‘Create an account’ option or simply fill in your details if you have an account already. Having an account on Biodiversity Advisor will provide users with free access to biodiversity resources.
In future, Team SANBI will be able to log in using their day-to-day login details, BGIS users will be able to use their existing accounts and details, and general users will be able to log in using their LinkedIn profile, but for now you will need to create an account.
