Envoy at 04:00, 4 May 2007

2007-05-04T04:00:58Z

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{{Taxobox
| color = lightgreen
| name = Rosaceae
| image = Crataegus_oxyacantha_L.jpg
| image_width = 200px
| image_caption = Flower of ''Rosa arvensis''
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Rosales]]
| familia = '''Rosaceae'''
| familia_authority = [[Antoine Laurent de Jussieu|Juss.]]
| subdivision_ranks = Subfamilies
| subdivision =
[[Rosoideae]] 
[[Spiraeoideae]] 
[[Maloideae]] 
[[Amygdaloideae]] or [[Prunoideae]]
| range_map = Map-Rosaceae.PNG
| range_map_width = 200px
| range_map_caption = Global distribution of Rosaceae
}}

The '''Rosaceae''' or [[rose]] family is a large [[family (biology)|family]] of [[plant]]s, with about 3,000-4,000 species in 100-120 genera. Traditionally it has been divided into four subfamilies: [[Rosoideae]], [[Spiraeoideae]], [[Maloideae]], and [[Amygdaloideae]]. These subfamilies are primarily diagnosed by the structure of the fruits, although this approach is not followed universally. Recent work has identified that the traditional four subfamilies are not all [[monophyletic]], but the structure of the family is still awaiting complete resolution.

Identified clades include:
* Subfamily [[Rosoideae]]: Traditionally composed of those genera bearing small fruits, each of which is an [[achene]] or [[drupelet]], and often the fleshy part of the fruit (e.g. [[Strawberry]]) is the [[hypanthium]] or the stalk bearing the carpels. The circumscription is now narrowed (excluding, for example, the tribe Dryadeae), but it still remains a diverse group containing 5 or 6 tribes and 20 or more genera. [[Rose]], [[Rubus|blackberry, raspberry]], [[Fragaria|strawberry]], ''[[Potentilla]]'', ''[[Geum]]''.
* Subfamily [[Spiraeoideae]]: Traditionally those genera which bear non-fleshy fruits consisting of five capsules. Now perhaps to be restricted to ''[[Spiraea]]'' and ''[[Sorbaria]]'' and their respective allies.
* Subfamily [[Maloideae]] (or Pomoideae): Traditionally this includes those genera ([[apple]], [[cotoneaster]], [[Crataegus|hawthorn]], [[pear]], [[quince]], [[rowan]], [[whitebeam]], etc), whose fruits consist of five capsules (called "cores") in a fleshy endocarp, surrounded by the ripened stem tissue. This fruit is called a [[pome]]. To these are added the woody genera ''[[Lindleya]]'' and ''[[Vauquelinia]]'', which share a [[haploid]] [[chromosome]] count of 17 (x=17) with the pomiferous genera, ''[[Kageneckia]]'', in which x=15, and the herbaceous genus ''[[Gillenia]]'' (x=9), which is the sibling to the remaining maloids.
* Subfamily [[Prunoideae|Amygdaloideae]] (or Prunoideae): Traditionally those genera whose fruits consist of a single [[drupe]] with a seam, two veins next to the seam, and one vein opposite the seam. Now extended to include the five genera ''[[Exochorda]], [[Maddenia]], [[Oemleria]], [[Prinsepia]]'' and ''[[Prunus]]'' ([[plum]], [[peach]], [[almond]], [[cherry]], [[apricot]]).
* Tribe [[Dryadeae]]: Fruits are achenes with hairy styles. Includes five genera ''([[Dryas_(plant)|Dryas]], [[Cercocarpus]], [[Chamaebatia]], [[Cowania]]'' and ''[[Purshia]]''), most species of which form [[root nodule]]s which host the nitrogen-fixing bacterium ''[[Frankia]]''.
* Tribe [[Neillieae]]: ''[[Neillia]]'' (including ''[[Stephanandra]]'') and ''[[Physocarpus]]''.

Amongst these groups, [[Neillieae]] appears to be the [[sister group]] to [[Maloideae]], and [[Dryadeae]] may be a sibling group to [[Rosoideae]]. Other genera, for example ''[[Kerria]]'', appear not to belong to any of these groups.

====A tongue-in-cheek poem====
::''The [[rose]] is a rose and was always a rose; But the theory now goes That the apple's a rose, And the pear is, and so's The plum, I suppose. The dear only knows What will next prove a rose. You, of course, are a rose, but were always a rose.''
:::- [[Robert Frost]], "The Rose Family".

==External links==
*[http://www.life.uiuc.edu/plantbio/260/Rosaceae/Rosehome.html Rosaceae] at the University of Illinois.

*[http://www.ibiblio.org/pfaf/cgi-bin/find_lat
?LAT=&COM=&FAM=Rosaceae&CAN=com Rosaceae full family list] at Plants For A Future - Species Database.

[[Category:Plant families]]
[[Category:Rosaceae]]

Rosaceae - Revision history

Envoy at 04:00, 4 May 2007