植物

Aa achalensis是兰科（Orchidaceae）天门冬目（Asparagales）的一种地生兰，隶属于Aa属——一个规模虽小但特征鲜明的类群，为南美安第斯山脉高海拔草原和帕拉莫（páramo）生态系统的地生兰属特有种。与该属其他成员一样，Aa achalensis为紧凑型多年生草本植物，通常由基生叶莲座丛生出直立的花序轴。叶片多呈椭圆形至披针形，肉质，质地略显多浆，是对该属所偏好的寒冷多风山地生境的适应性特征。花朵细小，沿花序轴密集排列，为Aa属的典型特征，在其原生高地环境中由昆虫传粉。Aa achalensis适应高海拔地区凉爽湿润的条件，当地降雨具有季节性，昼夜温差可能剧烈波动。种加词achalensis指其分布区相关的一处地理区域。与许多安第斯高山兰花一样，Aa achalensis面临栖息地退化、帕拉莫草原过度放牧以及气候变化改变其原生分布区脆弱温湿条件等威胁。Aa属由植物学家海因里希·古斯塔夫·赖兴巴赫（Heinrich Gustav Reichenbach）命名描述，所含已确认物种数量相对较少，其中许多因栖息地偏远、地形险峻而鲜为人知。保护安第斯高山生境对该物种及其近缘种的长期存续至关重要。

Aa argyrolepis为兰科（Orchidaceae）天门冬目（Asparagales）Aa属地生兰，该属为南美安第斯高海拔生境的特征类群。种加词argyrolepis源自希腊语词根，意为“银鳞状”，可能指其花苞片或叶表面在特定条件下呈现银白外观的显著特征。与Aa属其他成员相似，该种为莲座状丛生多年生草本，贴地丛生的基生叶密集簇生，可保护植株免受原生山地严酷环境的侵袭。花序轴自莲座丛中央垂直抽出，着生众多排列紧密的小花，为该属共有特征。花的结构通常精巧复杂，符合兰科特征，但相较许多观赏兰花而言体型较小。Aa argyrolepis生长于安第斯山脉无林的帕拉莫及普纳（puna）草原地带，该生态系统气候凉爽、日照强烈，且旱雨季分明。这些高海拔草原孕育着包括众多特有植物在内的特化植物区系。这类环境中Aa属兰花的传粉者通常为适应高山气候的小型昆虫。该物种面临家畜放牧、农业扩张及气候变化对安第斯生态系统持续影响所带来的保护压力。由于栖息地偏远，对Aa属的详细植物学研究目前仍较为有限。

Aa aurantiaca为兰科（Orchidaceae）天门冬目（Asparagales）地生兰，原产南美安第斯高海拔地区，隶属于Aa属——该属为适应安第斯高山寒冷、暴露草原及灌丛生境的地生兰类群，分布区涵盖哥伦比亚、厄瓜多尔、秘鲁及玻利维亚的帕拉莫地带。种加词aurantiaca在拉丁语中意为“橙色的”，暗示该种花朵可能带有橙色色素，这一暖色调花色在Aa属中相对少见，或使该种在同属中显得格外独特。与该属所有成员一样，Aa aurantiaca为紧凑型多年生草本，基生叶莲座丛中抽出直立的小花总状花序。叶片通常肉质或革质，以适应高海拔环境中常见的剧烈温差、强紫外线辐射及周期性干旱。小花沿花序轴密集排列，呈现兰科特有的复杂立体结构。在这些环境中为Aa属兰花传粉的多为适应高山草原生境的小型蜂类与蝇类。与许多安第斯兰花物种相似，Aa aurantiaca适应土层浅薄、排水良好且养分贫瘠的土壤。过度放牧导致的栖息地丧失、帕拉莫地区的焚烧以及气候驱动的植被带迁移，是该物种面临的主要保护关切。

Aa calceata is a terrestrial orchid classified within the family Orchidaceae, order Asparagales. It belongs to the genus Aa, a small genus of ground-dwelling orchids …

Aa colombiana is a terrestrial orchid in the family Orchidaceae, order Asparagales, belonging to the genus Aa. As its species name indicates, this orchid has …

Aa denticulata is a species of terrestrial orchid in the family Orchidaceae, order Asparagales. A member of the Andean genus Aa, this species takes its …

Aa erosa is a terrestrial orchid belonging to the family Orchidaceae, order Asparagales, and the Andean genus Aa. The species epithet erosa comes from the …

Aa fiebrigii is a terrestrial orchid in the family Orchidaceae, order Asparagales, placed within the Andean genus Aa. The species is named in honor of …

Aa figueroi is a species of terrestrial orchid classified within the family Orchidaceae, order Asparagales, and the South American genus Aa. The species epithet figueroi …

Aa hieronymi is a terrestrial orchid belonging to the family Orchidaceae, order Asparagales, and the Andean genus Aa. The species is named in honor of …

Aa lehmannii is a terrestrial orchid in the family Orchidaceae, order Asparagales, classified within the high-Andean genus Aa. The species is named in honor of …

Aa leucantha is a terrestrial orchid belonging to the family Orchidaceae, order Asparagales, and the South American genus Aa. The species epithet leucantha derives from …

Aa lorentzii is a species of terrestrial orchid in the family Orchidaceae, order Asparagales. A member of the Andean genus Aa, the species is named …

Aa lozanoi is a terrestrial orchid classified within the family Orchidaceae, order Asparagales, and the Andean genus Aa. The species epithet lozanoi honors an individual …

Aa macra is a species of terrestrial orchid in the family Orchidaceae, order Asparagales, belonging to the Andean genus Aa. The species epithet macra derives …

Aa maderoi为兰科（Orchidaceae）天门冬目（Asparagales）南美Aa属地生兰。种加词maderoi用以纪念一位姓Madero的人士，此人可能是与安第斯山区植物学野外考察相关的采集者、植物学家或资助人。与Aa属所有物种相同，Aa maderoi为紧凑型地生多年生草本，适应安第斯高海拔生态系统的严苛环境条件，分布区涵盖委内瑞拉、哥伦比亚、厄瓜多尔、秘鲁、玻利维亚及阿根廷西北部的帕拉莫及普纳草原。植株贴地丛生质地坚实、披针形至椭圆形的基生叶莲座丛，以减少受安第斯高海拔生境常见的强风及霜冻（尤以夜间为甚）影响。叶莲座丛中央抽出纤细直立的花序轴，顶端着生密集的小花穗。Aa maderoi单朵花虽小，结构却颇为精巧，具三枚萼片、两枚花瓣、特化唇瓣及愈合的合蕊柱，均为兰科的定义性特征。唇瓣在兰花传粉生物学中尤为重要，充当来访昆虫的着陆平台与导向结构。Aa maderoi生长于安第斯草原土层浅薄、常呈酸性的土壤中，依赖与土壤真菌形成的菌根共生关系有效吸收养分。兰花种子缺乏胚乳、养分储备极少，其萌发完全依赖这类真菌联合体的建立。保护完整的安第斯高山生态系统对该物种的存续至关重要。

Aa mandonii is a terrestrial orchid belonging to the family Orchidaceae, order Asparagales, placed within the Andean genus Aa. The species epithet mandonii honors Guillaume …

Aa matthewsii is a terrestrial orchid classified in the family Orchidaceae, order Asparagales, and the Andean genus Aa. The species epithet matthewsii commemorates Andrew Matthews, …

Aa microtidis is a terrestrial orchid in the family Orchidaceae, order Asparagales, belonging to the Andean genus Aa. The species epithet microtidis is derived from …

Aa paleacea为兰科（Orchidaceae）天门冬目（Asparagales）安第斯Aa属地生兰。种加词paleacea指其花序轴或花序上明显发育的糠秕状鳞片苞片（palea），使植株呈现糠秕状或鳞片状外观，有助于与Aa属其他近缘种相区别。这一形态特征在植物学上颇具意义，也反映在种名之中——该词源自拉丁语palea，意为“糠”或“壳”。Aa paleacea为紧凑型多年生草本，生长于安第斯高海拔草原生境，包括自哥伦比亚、厄瓜多尔向南延伸至秘鲁、玻利维亚的帕拉莫及普纳生态系统。在这些海拔高度，植被以禾草、垫状植物及低矮灌丛为主，均适应寒冷气温、强风、强紫外线辐射及周期性霜冻。植株贴地形成基生叶莲座丛，并抽出直立花序轴，着生众多兰科小花。与所有兰花相同，Aa paleacea的花两侧对称，萼片、花瓣、特化唇瓣与合蕊柱排列复杂。花序上的鳞片状糠秕苞片可能在严酷的高山环境中具有保护作用。Aa paleacea依赖菌根真菌完成幼苗定植及持续养分吸收。放牧、焚烧及气候变化仍是该物种赖以生存的安第斯高山生境所面临的主要威胁。

Aa riobambae is a terrestrial orchid in the family Orchidaceae, order Asparagales, belonging to the Andean genus Aa. The species epithet riobambae refers to Riobamba, …

Aa rosei is a terrestrial orchid in the family Orchidaceae, order Asparagales, belonging to the Andean genus Aa. The species epithet rosei honors Joseph Nelson …

Aa schickendanzii is a terrestrial orchid in the family Orchidaceae, order Asparagales, belonging to the Andean genus Aa. The species epithet schickendanzii honors an individual …

Aa sphaeroglossa is a terrestrial orchid in the family Orchidaceae, order Asparagales, and a member of the high-Andean genus Aa. The species epithet sphaeroglossa derives …

Aa trilobulata is a terrestrial orchid belonging to the family Orchidaceae, order Asparagales, and the Andean genus Aa. The species epithet trilobulata derives from the …

Aa weddelliana is a terrestrial orchid in the family Orchidaceae, order Asparagales, and a member of the high-Andean genus Aa. The species epithet weddelliana honors …