Aa

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Monocots
Ordo: Asparagales

Familia: Orchidaceae
Subfamilia: Orchidoideae
Tribus: Cranichideae
Subtribus: Cranichidinae
Genus: Aa
Overview of species (26)

A. achalensis – A. argyrolepis – A. aurantiaca – A. calceata – A. colombiana – A. denticulata – A. erosa – A. fiebrigii – A. figueroi – A. hieronymi – A. lehmannii – A. leucantha – A. lorentzii – A. lozanoi – A. macra – A. maderoi – A. mandonii – A. matthewsii – A. microtidis – A. paleacea – A. riobambae – A. rosei – A. schickendanzii – A. sphaeroglossa – A. trilobulata – A. weddelliana
Name

Aa Rchb.f., Xenia Orchid. 1: 18 (1854)

Type species: Aa paleacea (Kunth) Rchb.f., Xenia Orchid. 1: 18 (1854)
Typus: Aa paleacea (Kunth) Schltr. (Ophrys paleacea Kunth) selected by Schlechter, Repert. Spec. Nov. Regni Veg., 11: 147 (1912); Baillon, Dict. Bot., 4: 309 (1892); and Pfeiffer, Nomencl. Bot. (Pfeiffer), 1(1): 1 (1871)

Distribution
Native distribution areas:

Southern America
Central America
Costa Rica.
Northern South America
Venezuela.
Western South America
Bolivia, Colombia, Ecuador, Peru.
Brazil
Brazil North.
Southern South America
Argentina Northeast, Argentina Northwest.

References: Brummitt, R.K. 2001. TDWG – World Geographical Scheme for Recording Plant Distributions, 2nd Edition
References
Primary references

Pridgeon, A.M., Cribb, P.J., Chase, M.W. & Rasmussen, F.N. (eds.) 2003. Genera Orchidacearum Volume 3: Orchidoideae (Part two); page 24 ff., Oxford: Oxford University Press. ISBN 0-19-850711-9
Reichenbach, H.G. 1854. Xenia Orchidacea 1: 18.

Links

Global Biodiversity Information Facility. 2020. GBIF Backbone Taxonomy. Checklist dataset. Taxon: Aa (Orchidaceae). Accessed: 2020 Sep 4.
Govaerts, R. et al. 2020. Aa in Kew Science Plants of the World online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the internet. Accessed: 2020 Sep 4. Reference page.
Govaerts, R. et al. 2020. Aa in World Checklist of Selected Plant Families. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the internet. Accessed: 2020 Sep 4. Reference page.
International Plant Names Index. 2020. Aa. Published online. Accessed: 4 Sep 2020.
The Plant List 2013. Aa in The Plant List Version 1.1. Published on the internet. Accessed: 2020 Sep 4.
Tropicos.org 2020. Aa. Missouri Botanical Garden. Published on the internet. Accessed: 2020 Sep 4.

Vernacular names

Aa is a genus of plants of the family Orchidaceae.

Species in this genus can be found growing terrestrially in cold habitats near the snowline in the Andes and also in Costa Rica; they are usually found close to small streams. The elongated inflorescence grows from a basal rosette of leaves, terminating in a small white non-resupinate flower. This lip is fringed and hood-shaped. The flower gives off a pungent smell that attracts flies. This genus has often been included in the orchid genus Altensteinia.

The first scientific description of a species of this genus was made in 1815 by Karl Sigismund Kunth, naming it first Ophrys paleacea Kunth (1806)., and later Altensteinia paleacea. In 1854 Heinrich Gustav Reichenbach separated Aa from Altensteinia, to include two species Aa argyrolepis and Aa paleacea. The genus name apparently was rendered by the author to always appear first in alphabetical listings. Another - disputed - explanation, is that Heinrich Gustav Reichenbach named this genus after Pieter van der Aa; the printer of the Dutch botanist Paul Herman's "Paradisus Batavus".[1] A few years later, Reichenbach reviewed the name of the genus and named it again Altensteinia. Finally in 1912 Rudolf Schlechter switched the name again to Aa, as more species were being discovered making the new name more significant.

Species

The following species of Aa are accepted[2]

Aa achalensis Schltr. 1920 (Argentina)
Aa argyrolepis Rchb.f. 1854 (Colombia to Ecuador)
Aa aurantiaca D.Trujillo (Peru)[3][4]
Aa calceata (Rchb.f.) Schltr. 1912 (Peru to Bolivia)
Aa colombiana Schltr. 1920 (Colombia to Ecuador)
Aa denticulata Schltr. 1920 (Colombia to Ecuador)
Aa erosa (Rchb.f.) Schltr. 1912 (Peru)
Aa fiebrigii (Schltr.) Schltr. 1912 (Bolivia)
Aa figueroi Szlach. & S. Nowak, 2014 [5]
Aa hieronymi (Cogn.) Schltr. 1912 (Argentina)
Aa lehmanii Rchb. f. ex Szlach. & Kolan., 2014[6]
Aa leucantha (Rchb.f.) Schltr. 1920 (Colombia to Ecuador)
Aa lorentzii Schltr. 1920 (Argentina)
Aa lozanoi Szlach. & S. Nowak, 2014 [7]
Aa macra Schltr. 1921 (Ecuador)
Aa maderoi Schltr. 1920 (Venezuela; Colombia; Ecuador)
Aa mandonii (Rchb.f.) Schltr. 1912 (Peru to Bolivia)
Aa matthewsii (Rchb.f.) Schltr. 1912 (Peru)
Aa microtidis Schltr. 1922 (Bolivia)
Aa paleacea (Kunth) Rchb.f. 1854 (Costa Rica to Bolivia)
Aa riobambae Schltr. 1921 (Ecuador)
Aa rosei Ames 1922 (Peru)
Aa schickendanzii Schltr. 1920 (Argentina)
Aa sphaeroglossa Schltr. 1922 (Bolivia)
Aa trilobulata Schltr. 1922 (Bolivia)
Aa weddelliana (Rchb.f.) Schltr. 1912 (Peru to NW Argentina)

Synonyms:

Aa hartwegii Garay 1978 (Ecuador; Colombia; Venezuela); syn., → Aa maderoi Schltr.,[8]
Aa gymnandra (Rchb.f.) Schltr. 1912 a synonym of Myrosmodes gymnandra (Rchb.f.) C.A.Vargas[9]
Aa inaequalis (Rchb.f.) Schltr. 1912 (Peru to Bolivia); a synonym of Myrosmodes inaequalis (Rchb.f.) C.A.Vargas[10]
Aa nervosa (Kraenzl.) Schltr. 1912 (Chile); accepted name Myrosmodes nervosa (Kraenzl.) Novoa, C.A.Vargas & Cisternas[11]

References

"Paradisus batavus". Archived from the original on 2002-02-19.
"World checklist of selected plant families".
The Plant List: Aa
Tropicos: Aa aurantiaca
Tropicos: Aa figueroi
Tropicos: Aa lehmanii
Tropicos: Aa Lozanoi
World Checklist of Selected Plant Families (WCSP)
The Plant List: Aa gymnandra
The Plant List: Aa inaequalis

WCSP Aa nervosa (Kraenzl.) Schltr.

W.E. Higgins (2006): Selby Vignette: The Aa's of Orchids. [1]
H.G. Reichenbach. 1854. Xenia Orchidaceae. 1:18.
R. Schlechter (1912): Repertorium specierum novarum regni vegetabilis. Bd. XI S. 147ff. [2]