Heliophila

''Heliophila'' is a genus of flowering plants in the family Brassicaceae. Members of this genus are either annuals or perennials and some are popular as ornamental plants. Endemic to southern Africa, the majority of the approximately 80 species grow in South Africa, particularly the Cape Floristic Region, while a few extend into the Namib Desert.

Taxonomic history

The first recognised published description of ''Heliophila'' appears in the second edition of ''Species Plantarum'' by Carl Linnaeus, printed in 1763. He attributes his description, however, to Nicolaas Laurens Burman, a Dutch botanist. The generic name ''Heliophila'' is Latin but originally derived from the Ancient Greek words ''hēlios'' (ἥλιος), meaning "sun", and ''phílos'' (φίλος), meaning "dear" or "beloved", and refers to the blooms opening in sun and closing at night or in overcast conditions, a habit of many of the species within the genus.

In general, contention abounds regarding phylogenetic relationships in the family Brassicaceae. In the past, using morphological characters to establish tribes and genera was misleading and created dissension among systematists. The classification of species within Brassicaceae is gradually resolving through molecular phylogeny investigation, using internal transcribed spacer (ITS) data and other new-found sequencing knowledge.

Previously there were six genera within the tribe Heliophileae, all endemic to southern Africa: ''Heliophila'', ''Cycloptychis'', ''Schlechteri'', ''Silicularia'', ''Thlaspeocarpa'', and ''Brachycarpaea''. The latter five genera contained among them only seven species, having been differentiated from the genus ''Heliophila'' mainly on morphological differences in the fruits they bore. Following extensive analysis of molecular evidence (nuclear (ITS) and plastid (trnL-F) DNA sequence data), Heliophileae was found to be monophyletic and the five small genera were reduced to synonymy with ''Heliophila''.

Distribution

''Heliophila'' is one of only two genera of Brassicaceae endemic to southern Africa. The majority of the species grow in the winter-rainfall Cape Floristic Region and the more arid Namaqualand, while a smaller portion extend to the rest of South Africa, Namibia, Swaziland, and Lesotho. None of the members of this genus are listed on the IUCN Red List of Threatened Species.

Description and habit

''Heliophila'' is regarded as one of the most diverse genera in the family Brassicaceae. Flower size, for example, varies greatly, with this genus containing both the largest of petals within the family (''H. juncea'') to the smallest (''H. pectinata''). There is a range of flower colour, with blue, white, and pink being the most common. Blue is an unusual colour for Brassicaceae, being known in only one other genus, the unrelated '' Solms-laubachia'' from the Himalayas.

Within the genus are mainly herbs and subshrubs, although shrubs and lianas appear as well. They may be annual or perennial and the majority of the fruits produced by species in this genus are dehiscent, not woody, and lack a carpophore. The plants are generally either glabrous or possess simple hairs. Leaves are variable; they are narrow or broad, but usually simple, and may be entire, lobed, or pinnatipartite. The inflorescences are usually the raceme type.

Species

Accepted species:
* '' Heliophila acuminata'' ( Eckl. & Zeyh.) Steud, 1840
* '' Heliophila adpressa'' O.E. Schulz
* '' Heliophila affinis'' Sond., 1846
* '' Heliophila africana'' ( L.) Marais, 1970
* '' Heliophila alpina'' Marais
* '' Heliophila amplexicaulis'' L.f., 1782
* '' Heliophila arenaria'' Sond.
* '' Heliophila arenosa'' Schltr., 1899
* '' Heliophila brachycarpa'' Meisn., 1842
* '' Heliophila brassicaefolia'' Eckl. & Zeyh.
* '' Heliophila brassicifolia'' Eckl. & Zeyh.
* '' Heliophila bulbostyla'' Barnes
* '' Heliophila callosa'' (L.f.) DC., 1821
* '' Heliophila carnosa'' (Thunb.) Steud., 1840
* '' Heliophila cedarbergensis'' Marais
* '' Heliophila cinerea'' Marais, 1970
* '' Heliophila collina'' O.E. Schulz
* '' Heliophila concatenata'' Sond., 1846
* '' Heliophila cornellsbergia'' B.J. Pienaar & Nicholas
* '' Heliophila cornuta'' Sond., 1846
* '' Heliophila carnosa'' (Thunb.) Steud., 1840
* '' Heliophila coronopifolia'' L.
* '' Heliophila crithmifolia'' Willd., 1809
* '' Heliophila cuneata'' Marais
* '' Heliophila decurva'' Schltr., 1913
* '' Heliophila deserticola'' Schltr., 1913
* '' Heliophila diffusa'' (Thunb.) DC.
* '' Heliophila digitata'' L.f., 1782
* '' Heliophila dissecta'' Thunb.
* '' Heliophila dregeana'' Sond., 1846
* '' Heliophila elata'' Sond.
* '' Heliophila elongata'' DC.
* '' Heliophila ephemera'' P.A.Bean
* '' Heliophila esterhuyseniae'' Marais
* '' Heliophila eximia'' Marais
* '' Heliophila filicaulis'' Marais
* '' Heliophila formosa'' Hilliard & B.L.Burtt
* '' Heliophila gariepina'' Schltr.
* '' Heliophila glauca'' Burch. ex DC.
* '' Heliophila hurkana'' Al-Shehbaz & Mumm.
* '' Heliophila juncea'' (P.J.Bergius) Druce
* '' Heliophila katbergensis'' Marais
* '' Heliophila laciniata'' Marais
* '' Heliophila lactea'' Schltr.
* '' Heliophila leptophylla'' Schltr.
* '' Heliophila linearis'' DC.
* '' Heliophila linoides'' Schltr.
* '' Heliophila macowaniana'' Schltr.
* '' Heliophila macra'' Schltr.
* '' Heliophila macrosperma'' Burch. ex DC.
* '' Heliophila maraisiana'' Al-Shehbaz & Mumm.
* '' Heliophila meyeri'' Sond.
* '' Heliophila minima'' (Stephens) Marais
* '' Heliophila monosperma'' Al-Shehbaz & Mumm.
* '' Heliophila namaquana'' Bolus
* '' Heliophila namaquensis'' (Marais) Al-Shehbaz & Mumm.
* '' Heliophila nubigena'' Schltr.
* '' Heliophila obibensis'' Marais
* '' Heliophila patens'' Oliv.
* '' Heliophila pectinata'' Burch. ex DC.
* '' Heliophila pendula'' Willd.
* '' Heliophila pinnata'' L.f.
* '' Heliophila polygaloides'' Schltr.
* '' Heliophila promontorii'' Marais
* '' Heliophila pubescens'' Burch. ex Sond.
* '' Heliophila pusilla'' L.f.
* '' Heliophila ramosissima'' O.E.Schulz
* '' Heliophila refracta'' Sond.
* '' Heliophila remotiflora'' O.E.Schulz
* '' Heliophila rigidiuscula'' Sond.
* '' Heliophila rimicola'' Marais
* '' Heliophila scandens'' Harv.
* '' Heliophila schulzii'' Marais
* '' Heliophila scoparia'' Burch. ex DC.
* '' Heliophila seselifolia'' Burch. ex DC.
* '' Heliophila suavissima'' Burch. ex DC.
* '' Heliophila suborbicularis'' Al-Shehbaz & Mumm.
* '' Heliophila subulata'' Burch. ex DC.
* '' Heliophila tabularis'' Dod
* '' Heliophila thunbergii'' Steud.
* '' Heliophila tricuspidata'' Schltr.
* '' Heliophila trifurca'' Burch. ex DC.
* '' Heliophila tulbaghensis'' Schinz
* '' Heliophila variabilis'' Burch. ex DC.

References

{{Taxonbar, from=Q955407

Brassicaceae
Brassicaceae genera