Olea is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of about 40 species in the family Oleaceae

Oleaceae

Oleaceae are a family containing 24 extant genera and around 600 species of mesophytic shrubs, trees and occasionally vines. As shrubs, members of this family may be twine climbers, or scramblers.-Leaves:...

, native to warm temperate and tropical regions of southern Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, Africa

Africa

Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

, southern Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

 and Australasia

Australasia

Australasia is a region of Oceania comprising Australia, New Zealand, the island of New Guinea, and neighbouring islands in the Pacific Ocean. The term was coined by Charles de Brosses in Histoire des navigations aux terres australes...

. They are evergreen

Evergreen

In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...

 tree

Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

s and shrub

Shrub

A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

s, with small, opposite, entire leaves

Leaf

A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

. The fruit

Fruit

In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

 is a drupe

Drupe

In botany, a drupe is a fruit in which an outer fleshy part surrounds a shell of hardened endocarp with a seed inside. These fruits develop from a single carpel, and mostly from flowers with superior ovaries...

.Leaves of Olea contain Tricho sclereids.

For humans, the most important species is by far the Olive

Olive

The olive , Olea europaea), is a species of a small tree in the family Oleaceae, native to the coastal areas of the eastern Mediterranean Basin as well as northern Iran at the south end of the Caspian Sea.Its fruit, also called the olive, is of major agricultural importance in the...

 (Olea europaea), native to the Mediterranean region. O. paniculata is a larger tree, attaining a height of 15-18 m in the forests of Queensland

Queensland

Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

, and yielding a hard and tough timber

Timber

Timber may refer to:* Timber, a term common in the United Kingdom and Australia for wood materials * Timber, Oregon, an unincorporated community in the U.S...

. The yet harder wood of the Black Ironwood

Black Ironwood

Black ironwood could refer to one of the following:*Black ironwood, Olea capensis, a species of tree found in afromontane forests throughout Africa.*Black ironwood, Olea laurifolia, a species of tree found in Kwazulu Natal, South Africa....

 O. laurifolia, an inhabitant of Natal, is important in South Africa

South Africa

The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

.

Olea species are used as food plants by the larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e of some Lepidoptera

Lepidoptera

Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

 species including Double-striped Pug

Double-striped Pug

The Double-striped Pug is a moth of the family Geometridae. It is a widespread and common species, being found throughout the Palearctic region, the Near East and North Africa....

.

Selected species

• Olea ambrensis H.Perrier
• Olea borneensis Boerl.
• Olea brachiata (Lour.) Merr.
• Olea capensis
  Olea capensis
  Olea capensis, the Black Ironwood tree, is an African tree species belonging to the olive family . Olea capensis is widespread in Africa. It is found almost throughout Africa south of the Sahara desert from the east in Somalia, Ethiopia and Sudan, south to the tip of South Africa, and west to...
  
  L. – Small Ironwood
• Olea caudatilimba L.C.Chia
• Olea chimanimani
  Olea chimanimani
  Olea chimanimani is an olive shrub or small tree, growing 2–3 meters tall, in the family Oleaceae. It is found only in the Chimanimani mountains , which lay on the border dividing Mozambique and Zimbabwe. Confined only to a relatively small area, it is locally common, growing in scrub vegetation...
  
  Kupicha
• Olea chrysophylla Lam.
• Olea cordatula H.L.Li
• Olea dioica Roxb.
• Olea europaea L. – Olive
• Olea exasperata Jacq.
• Olea gagnepainii Knobl.
• Olea gamblei C.B.Clarke
• Olea guangxiensis B.M.Miao
• Olea hainanensis H.L.Li
• Olea javanica (Blume) Knobl.
• Olea lancea Lam.
• Olea laurifolia
  Olea laurifolia
  Olea laurifolia is a species of flowering plant belonging to the olive family Oleaceae. It is native to KwaZulu-Natal Province, South Africa....
  
  Lam. – Black Ironwood
• Olea laxiflora H.L.Li
• Olea moluccensis Kiew
• Olea neriifolia H.L.Li
• Olea obovata (Merr.) Kiew
• Olea oleaster
  Olea oleaster
  Olea oleaster, the wild-olive, has been considered by various botanists a valid species and a subspecies of the cultivated olive tree, Olea europea, which is a tree of multiple origins that was domesticated, it now appears, at various places during the fourth and third millennia BCE, in selections...
  
  Hoffmanns. & Link – Wild-olive
• Olea palawanensis Kiew
• Olea paniculata
  Olea paniculata
  Olea paniculata, commonly known as the Native Olive, is a plant of the genus Olea and a relative of the olive. It is found from Yunnan in southwestern China and Pakistan across southern Asia to Australia and New Caledonia, Vanuatu and Lord Howe Island in the Pacific Ocean.-Taxonomy:One of many...
  
  R.Br.
• Olea parvilimba (Merr. & Chun) B.M.Miao
• Olea polygama Wight
• Olea rosea Craib
• Olea rubrovenia (Elmer) Kiew
• Olea salicifolia Wall. ex G.Don
• Olea schliebenii Knobl.
• Olea sylvestris Mill.
• Olea tetragonoclada L.C.Chia
• Olea tsoongii (Merr.) P.S.Green
• Olea undulata (Sol.) Jacq.
• Olea welwitschii (Knobl.) Gilg & G.Schellenb.
• Olea wightiana Wall. ex G.Don
• Olea woodiana Knobl.
• Olea yuennanensis Hand.-Mazz.

List sources :

Formerly placed here

• Chionanthus foveolatus
  Chionanthus foveolatus
  Chionanthus foveolatus is a medium-sized, evergreen, Afromontane tree that is indigenous to South Africa....
  
  (E.Mey.) Stearn (as O. foveolata E.Mey.)
• Ligustrum compactum var. compactum (as O. compacta Wall. ex G.Don)
• Nestegis cunninghamii (Hook.f.) L.A.S.Johnson (as O. cunninghamii Hook.f.)
• Noronhia emarginata
  Noronhia emarginata
  Noronhia emarginata is a species of Noronhia native, and endemic to, Madagascar....
  
  (Lam.) Thouars (as O. emarginata Lam.)
• Osmanthus americanus (L.) Benth. & Hook.f. ex A.Gray (as O. americana L.)
• Osmanthus heterophyllus
  Osmanthus heterophyllus
  Osmanthus heterophyllus is a species of Osmanthus native to eastern Asia in central and southern Japan and Taiwan.It is an evergreen shrub or small tree growing to 2–8 m tall...
  
  (G. Don) P.S.Green (as O. aquifolium Siebold & Zucc. or O. ilicifolia Siebold ex Hassk.)

List source :