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6.Polystichum 耳蕨屬
　地生，根莖短，具鱗片，植株叢生。植株鱗片多形，不具毛，葉革質，線形或卵披針形，一至二回 羽狀複葉，上先型，羽片邊緣多少有鋸齒，孢子囊群圓形。
　臺灣有24種。

種檢索表

　1.網脈 ....................................................................................................2
　1.游離脈 ................................................................................................7
　2.羽軸兩側各具一排孢子囊群 .........................................11.網脈耳蕨
　2.羽軸兩側孢子囊群多排 ....................................................................3
　3.羽片漸縮，不具頂羽片 .............................................15.狹葉貫眾蕨
　3.明顯具頂羽片 ....................................................................................4
　4.孢膜鋸齒，羽片規則鋸齒 ...........................................5.細齒貫眾蕨
　4.孢膜全緣，羽片邊緣不規則 ............................................................5
　5.葉厚革質，羽片窄，約2cm寬 .........................................................6
　5.葉厚草質，羽片寬，約5cm ........................................9.全緣貫眾蕨
　6.孢膜帽狀突起 .............................................................30.臺灣貫眾蕨
　6.不具上述特徵 ...............................................................2.尖葉貫眾蕨
　7.葉緣呈波浪狀，羽軸延長，並具有頂芽 .....................18.鞭葉耳蕨
　7.葉緣鋸齒，多少有芒刺，即使有芽羽軸亦不延長 ........................8
　8.三出羽狀複葉 .................................................................12.韓氏耳蕨
　8.羽狀複葉 ............................................................................................9
　9.一回羽狀複葉 ..................................................................................10
　9.二回羽狀裂葉至二回羽狀複葉 ......................................................18
　10.羽片長寬比大於4，絕不小於3.5 ...................................................11
　10.羽片長寬比在1~3之間 ....................................................................12
　11.羽片耳尖明顯，下緣弧形 ...............................................3.臺東耳蕨
　11.羽片耳尖圓鈍，下緣平直 .............................................10.臺灣耳蕨
　12.羽片具軟骨質邊緣 .........................................................22.軟骨耳蕨
　12.羽片均質，不具軟骨質邊緣 ..........................................................13
　13.羽片邊緣反捲 ...................................................................7.杜氏耳蕨
　13.羽片邊緣不反捲 ..............................................................................14
　14.羽軸頂端有芽 ..................................................................................15
　14.羽軸頂端無芽 ..................................................................................16
　15.葉草質，孢膜大，直徑大於2mm，葉脈末端無泌水孔 ..........................................................................................20.玉山耳蕨
　15.葉革質，孢膜小，葉脈末端具泌水孔 .........................28.芽孢耳蕨
　16.基羽片反折朝下 .........................................................13.鋸齒葉耳蕨
　16.基羽片不反折 ..................................................................................17
　17.羽片下表面鱗片具分叉 ...................................................6.對生耳蕨
　17.羽片下表面鱗片單尾 .....................................................24.知本耳蕨
　18.羽軸頂端有芽 .................................................................27.鋸葉耳蕨
　18.羽軸頂端無芽 ..................................................................................19
　19.葉脈末端具泌水孔 ..........................................................................20
　19.葉脈末端無泌水孔 ..........................................................................26
　20.葉大，寬披針形，長寬比約2:1，葉寬15cm以上 ........................21
　20.葉小，窄線形，長寬比約4:1，葉寬5cm以下 ..............................22
　21.葉軸鱗片小 .......................................................................4.二尖耳蕨
　21.葉軸鱗片具較大的卵圓形和較小的披針形 .............29.兒玉氏耳蕨
　22.下羽片偏短且朝下 .....................................................33.福山氏耳蕨
　22.不具上述特徵 ..................................................................................23
　23.小羽片之鋸齒長短不一 .................................................26.南湖耳蕨
　23.小羽片僅具短鋸齒 ..........................................................................24
　24.孢子囊群在小脈末端 .....................................................31.尾葉耳蕨
　24.孢子囊群在小脈中段 .....................................................17.高山耳蕨
　25.葉硬革質，具長尖刺 ......................................................................26
　25.葉草質至革質，不具長尖刺 ..........................................................27
　26.葉長披針形 ......................................................................1.針葉耳蕨
　26.葉卵圓形 ........................................................................21.硬葉耳蕨