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in biology, Asphodeloideae is a subfamily of the monocot family Asphodelaceae in the order Asparagales. It has previously been treated as a separate family, Asphodelaceae sensu stricto. There are about 785 species in 15 genera, mainly distributed in Africa, the Mediterranean coast and Central Asia. Only the genus Pteris (or "Cocktail Orchid") is native to New Zealand. Most of the undergraduate plants are succulent plants. The species grows in South Africa.In the previous taxonomy, most of the genera of this family were classified in Liliaceae. In 1998, the APG taxonomy classified according to the genetic relationship classified it as a separate family, which belonged to Asparagus. In 2003, the revised APG II taxonomy classified It is listed as a family that can choose to merge with Echinaceae (now Xanthoaceae) and Hemerocallis, especially the close relationship with Echinaceae.
The Asphodeloideae are distinguished by a general presence of anthraquinones, simultaneous microsporogenesis, atypical ovules morphology, and the presence of an aril. Asphodeloideae also have a characteristic secondary growth by means of a secondary thickening meristem. This character, however, is also found in other taxa in the Asparagales, including Agavaceae, Iridaceae, and Xanthorrhoeoideae. It is confined to Asparagales among the monocots and is believed to have evolved independently in most families.
Asphodeloideae rhizomes, sometimes massive and with fleshy roots, rarely tubers or bulbs, leaves usually subbasal and in clusters; inflorescences terminal; anthers extroverted, sometimes dehiscing at the apex; capsule dehiscing or rarely compartmental Dehiscing, rarely berrylike.
Aloin cells
The presence of aloin cells is a distinctive character of the Aloeae. These cells are present in all Aloeae, but are absent in most of the other genera within Asphodeloideae. A well-developed cap of thin-walled parenchyma cells occurs at the phloem pole of each vascular bundle. Chase posits that they are involved in secondary metabolite production, but Beaumont suggests that the cells act as a storage tissue for compounds synthesized in the surrounding layer of cells. The aloin cells are said to produce the characteristic thick exudate that is produced when the succulent leaf of aloe is severed. The aloin cells produce anthraquinone and chromone derivatives, which may be responsible for the medicinal attributes of Aloe.