{{Taksonomka
| name = Kukavičevke
| fossil_range = pozna kreda- recentno
| image = Haeckel Orchidae.jpg
| image_width = 200px
| image_caption = Ernst Haeckel ''Kunstformen der Natur''
| regnum = Plantae (rastline)
| divisio = Magnoliophyta (kritosemenke)
| classis = Liliopsida (dvokaličnice)
| ordo = Asparagales (beluševci)
| familia = '''Orchidaceae'''
| familia_authority = Juss.
| subdivision_ranks = Poddružine
| subdivision = 
* Apostasioideae
* Cypripedioideae
* Epidendroideae
* Orchidoideae
* Vanilloideae
}}
left|150px|thumb|Fuchsova prstasta kukavica - Dactylorhiza maculata ssp. fuchsii'''Kukavičevke''' (botanična družina v kateri ljubitelji orhidej vedno znova odkrivajo nove vrste in različne križance. Družina kukavičevk obsega okoli 20.000 različnih vrst in podvrst. Največ vrst najdemo v tropskih predelih Južne Amerike in jugovzhodne Azije. V Evropi raste okoli 300 vrst, v Sloveniji pa je bilo do sedaj najdenih 76 vrst.

Cvet kukavičevk je someren in sestavljen iz šestih cvetnih listov, ki so razvrščeni v dveh vretencih: zunanjem vretencu treh listov (sepal) in notranjem vretencu treh listov (petal), od katerih največjemu srednjemu listu pravimo medena ustna (labelum). Medena ustna je navadno podaljšana v ostrogo, v katerih se nahajajo žleze.

left|150px|thumb|Fuchsova prstasta kukavica - Dactylorhiza maculata ssp. fuchsiikalitvi ne morejo hraniti rastlinsko zasnovo. Vlogo prehranjevanja opravljajo glive pestunje in mlade rastlinice postanejo odvisne od gljive pestunje. Šele po nekaj letih se razvijejo prvi zeleni listi, cveteti pa pričnejo šele po nekaj letih. Odrasle rastline ostanejo v tesni povezavi z hifami gliv, ta simbioza se imenuje mikoriza.

Zelo zapleten razvoj in velike občutljivosti na gnojila povzroča, da so Kukavičevke zelo ogrožena družina rastlin v Sloveniji. Večina vrst je zaščitenih, zato je najboljše, če pustimo te prelepe rastline rasti in jih ne trgamo.

Ena najbolj znanih vrst orhidej je Vanilija, ki je tudi ena redkih uporabnih vrst orhidej. V Sloveniji pa so najbolj znane Orhideje zagotovo Murke, ki imajo pomembno mesto v pesmi ''Tam kjer murke cveto'' Slavka Avsenika.

==Zunanje povezave==
*[http://www.orhideje.si/index1.html Slovenske orhideje]
*[http://www.zaplana.net/flowers/wildorchids/orhideje.asp Zaplana - Orhideje]

== Viri ==
* ''Orhideje Slovenije'' - Vlado Ravnik, 2002, ISBN 86-365-0411-2

Kategorija:Beluševci
*
Kategorija:Botanične družine

{{Taxobox
| name = Orchidaceae
| fossil_range = Late Cretaceous- Recent
| image = Haeckel Orchidae.jpg
| image_width = 200px
| image_caption = Color plate from Ernst Haeckel's ''Kunstformen der Natur''
| regnum = Plantae
| divisio = Magnoliophyta
| classis = Liliopsida
| ordo = Asparagales
| familia = '''Orchidaceae'''
| familia_authority = Juss.
| subdivision_ranks = Subfamilies
| subdivision = 
* Apostasioideae
* Cypripedioideae
* Epidendroideae
* Orchidoideae
* Vanilloideae
}}

'''Orchidaceae''' (or '''Orchid family''') is the largest family of the flowering plants (Angiospermae). <ref> [http://hypertextbook.com/facts/2003/BiancaNicoletti.shtml Number of orchids] </ref> <ref> [http://www.kew.org/scihort/orchids/whystudy.html Orchid Fact File, Royal Botanic gardens, Kew] </ref> Its name is derived from the genus ''Orchis''.

The genera and nearly 22,000 accepted vanilla plant), ''Orchis'' (type genus) and many commonly cultivated plants like some ''Phalaenopsis'' or ''Cattleya''.  

Moreover,  since the introduction of tropical species in the 19th century, horticulturists have more than 100,000 hybrids and cultivars.

== Distribution ==
Orchidaceae are cosmopolitan, occurring in almost every habitat apart from deserts and glaciers. The great majority are to be found in the tropics, mostly Asia, South America and Central America. They are found above the Arctic Circle, in southern Patagonia and even on Macquarie Island, close to Antarctica.

The following list gives a rough overview of their distribution:
* tropical America: 250 to 270 genera
* tropical Asia: 260 to 300 genera
* tropical Africa: 230 to 270 genera
* Oceania: 50 to 70 genera
* Europe and temperate Asia: 40 to 60 genera
* North America: 20 to 25 genera

==Taxonomy==

This family is totally recognised, and the APG II system of 2003 places it in the order Asparagales.

The taxonomy of this family is in constant flux, as new studies continue to identify more classificatory elements. 

Five subfamilies are now recognised. The cladogram has been made according to the APG system:

{{clade|style=font-size:80%;line-height:75%
|1={{clade|1='''Apostasioideae''': 2 genera and 16 species, south-western Asia
|2={{clade|1='''America|label2=&nbsp;Monandrae&nbsp;
|2={{clade|1='''Vanilloideae''': 15 genera and 180 species, humid tropical and subtropical regions, eastern North America
|2={{clade|1='''Epidendroideae''': more than 500 genera and more or less 20 000 species, cosmopolitan
|2='''Orchidoideae''': 208 genera and 3,630 species, cosmopolitan
}}}}}}}}}}

==Ecology==

thumb|left|''[[Neottia nidus-avis'', a myco-heterotroph ]]

A majority of orchids are perennial epiphytes, which grow anchored to trees or shrubs in the tropics and subtropics. Other species are lithophytes, growing on rocks or very rocky soil, or are terrestrial. Nearly all temperate orchids are terrestrial.

Some orchids, like ''parasitising soil fungi through the formation of holoparasites, all orchids are myco-heterotrophic during germination and seedling growth and even photosynthetic adult plants may continue to obtain carbon from their mycorrhizal fungi.

==Description==
301px|thumb|''Cattleya aclandiae''. Note the typical [[zygomorphic flower with three petal-like sepals (top, lower right, lower left), two normal petals on either side and  the labellum]]

Orchids are easily distinguished, as they share some very evident apomorphies. Among these: bilaterally symmetric (zygomorphic) and resupinate, a petal (''labellum'') is always highly modified, stamens and carpels are fused, and the seeds are extremely small. 

===Leaves===
Like most leaves with parallel venation. They may be ovate, lanceolate, or orbiculate and very variable in size. Their characteristics are often diagnostic. They are normally alternate on the stem, often plicate, and have no siliceous bodies called ''stegmata'' in the vascular bundle sheaths (not present in the Orchidoideae) and are fibrous.

The structure of the leaves corresponds to the specific habitat of the plant. Species that typically bask in sunlight, or grow on sites which can be occasionally very dry, have thick, leathery leaves and the cuticle to retain their necessary water supply. Shade species, on the other hand, have long, thin leaves.

The leaves of most orchids are perennial, that is they live for several years, while others, especially those with plicate leaves, shed them annually and develop new leaves together with new pseudobulbs, as in ''Catasetum''.

The leaves of some orchids are considered ornamental. The leaves of the ''Macodes sanderiana'', a semiterrestrial or lithophyte, show a sparkling silver and gold veining on a light green background. The cordate leaves of ''Psychopsiella limminghei'' are light brownish green with maroon-puce markings, created by flower pigments. The attractive mottle of the leaves of Lady's Slippers from temperate zones (''Paphiopedilum'') is caused by uneven distribution of chlorophyll. Also ''Phalaenopsis schilleriana'' is a lovely pastel pink orchid with leaves spotted dark green and light green. The '''Jewel Orchid''' (''Ludisia discolor'') is grown more for its colorful leaves than its fairly inconspicuous white flowers.

Some orchids, as ''Polyrrhiza lindenii'' (heterotrophic species.

===Stem and roots===
All orchids are perennial herbs and lack any permanent woody structure. Orchids can grow according to two patterns:

* '''Monopodial''': The stems grows from a single bud, leaves are added from the apex each year and the stem grows longer accordingly. The stem of orchids with a monopodial growth can reach several metres in length, as in ''Vanda'' and ''Vanilla''.
* '''Sympodial''': The plant produces a series of adjacent shoots which grow to a certain size, bloom and then stop growing, to be then replaced. Sympodial orchids grow laterally rather than vertically, following the surface of their support. The growth continues by development of new leads, with their own leaves and roots, sprouting from or next to those of the previous year, as in ''Cattleya''. While a new lead is developing, the rhizome may start its growth again from a so-called 'eye', an undeveloped bud, thereby branching.

thumb|left|''[[Orchis lactea'' showing the two tubers]]
Terrestrial orchids may be rhizomatous or form corms or tubers. The root caps of terrestrials are smooth and white.

Some sympodial terrestrials, such as ''Orchis'' and ''Ophrys'', have two subterranean tuberous roots. One is used as a food reserve for wintry periods, and provides for the development of the other one, from which visible growth develops. 

In warm and humid climates, many terrestrial orchids do not need pseudobulbs.

Epiphytic orchids have modified epidermis called ''velamen'' has the function to absorbe humidity. It is made of dead cells and can have a silvery-grey, white or brown appearance. 

The cells of the root epidermis grow at a right angle to the axis of the root to allow them to get a firm grasp on their support. Nutrients mainly come from animal droppings on their supporting tree. 

The base of the stem of sympodial epiphytes, or in some species essentially the entire stem, may be thickened to form what is called a ''pseudobulb'' that contains nutrients and water for drier periods.

thumb|The pseudobulb of ''Prosthechea fragrans''
The pseudobulb has a smooth surface with lengthwise grooves and can have different shapes, often conical or oblong. Its size is very variable; in ''Bulbophyllum'' (black orchids) it is no longer than two millimeters, while in the largest orchid in the world, ''Grammatophyllum speciosum'' (giant orchid), it can reach three meters. Some ''Dendrobium'' have long, canelike pseudobulbs with short, rounded leaves over the whole length, some other orchids have hidden or extremely small pseudobulbs, completely included inside the leaves.

With ageing the pseudobulb sheds its leaves and becomes dormant. At this stage it is often called a ''backbulb''. A pseudobulb then takes over, exploiting the last reserves accumulated in the backbulb, which eventually dies off too. A pseudobulb typically lives for about five years.

===Flower===
left|291px|thumb|''Dactylorhiza sambucina'', [[Orchidoideae for reference]]
Orchidaceae are well known for the many structural variations in their flowers.

Some orchids have single flowers but most have a racemose inflorescence, sometimes with a large number of flowers. The flowering stem can be ''basal'', that is produced from the base of the tuber, like in ''Cymbidium'', ''apical'', meaning it grows from the apex of the main stem, like in ''Cattleya'', or ''axillary'', from the leaf axil, as in ''Vanda''.

As an bilaterally symmetrical), although in some genera like ''Mormodes'', ''Ludisia'', ''Macodes'' this kind of symmetry may be difficut to notice. 

The orchid flower, like most flowers of monocots has two whorls of sterile elements. The outer whorl has three sepals and the inner whorl has three petals. The sepals are usually very similar to the petals (and thus called ''tepals'', '''1'''), but may be completely distinct.

The upper <!--- Yes, the *upper*. Read what follows, please --->medial petal, called the ''apomorphic (the torsion of the ovary is very evident from the picture). Some orchids have secondarily lost the resupination, like some ''Zygopetalum'.

The normal form of the sepals can be found in ''Cattleya'', where they form a triangle. In ''Paphiopedilum'' (Venus slippers) the lower two sepals are fused together into a synsepal, while the lip has taken the form of a slipper. In ''Masdevallia'' all the sepals are fused.

Orchid flowers with abnormal numbers of petals or lips are called ''peloric''. Peloria is a genetic trait, but its expression is environmentally influenced and may appear random.

thumb|Longitudinal section of a flower of ''[[Vanilla planifolia''|401px|right]]
Orchid flowers primitively had three adnate (fused) to the style to form cylindrical structure called the ''gynostemium'' or column ('''2'''). In the primitive stigma ('''9''') is very asymmetrical as all of its lobes are bent towards the centre of the flower and lay on the bottom of the column.

pollinia. 

A pollinium is a waxy mass of pollen grains held together by the glue-like stipe'', like in ''Vanda''. Caudicles or stipes hold the pollinia to the ''viscidium'', a sticky pad which sticks the pollinia to the body of pollinators.

At the upper edge of the stigma of single-anthered orchids, in front of the anther cap, there is the ''rostellum'' ('''5'''), a slender extension involved in the complex pollination mechanism.

As aforementioned, the ovary is always inferior (located behind the flower). It is three-carpelate and one or, more rarely, three-partitioned, with parietal placentation (axile in the Apostasioideae).

===Pollination=== 
Orchids have developed highly specialized pollination systems and thus the chances of being pollinated are often scarce. This is why orchid flowers usually remain receptive for very long periods and why most orchids deliver pollen in a single mass; each time pollination succeeds thousands of ovules can be fertilized.

Pollinators are often visually attracted by the shape and colours of the labellum. The flowers may produce attractive odours. Although absent in most species, spur ('''8''') of the labellum, on the point of the sepals or in the septa of the ovary, the most typical position amongst the Asparagales. 