마과 Dioscoreaceae

마속 Dioscorea LINN.

1. 잎은 대생(간혹 호생)하며 잎겨드랑이에 살눈이 달린다.

2. 잎은 심장상 피침형이며 열매는 지름 25~28mm 이다 ··················································································642. 참마

2. 잎은 심장상 난형이고 열매는 지름 18-20mm 이다 ························································································643. 마

1. 잎은 호생한다.

3. 지하경은 둥글고 잎겨드랑이에 살눈이 생기며 수꽃 화피는 자줏빛이다 ··························································· 644. 둥근마

3. 지하경은 길고 살눈이 없으며 화피는 황록색이다.

4. 종자는 한쪽에만 날개가 있다.

5. 잎은 밋밋하고 털이 없으며 꽃은 옆으로 퍼진다  ···············································································645. 도꼬로마

5. 잎은 손바닥모양으로 갈라지며 털이 있고 꽃은 수평으로 퍼지지 않는다  ·····················································646. 부채마

4. 종자는 전면에 날개가 있다.

6. 잎은 가장자리가 밋밋하며 털이 없고 수꽃은 밑으로 처지며 소화경이 있다 ··················································· 647. 각시마

6. 잎은 손바닥모양으로 갈라진다.

7. 식물체는 마르면 담녹색으로 되고 잎자루 밑에 작은 돌기가 있으며 수꽃에 대가 없다  ··································· 648. 단풍마

7. 식물체는 마르면 검게 되고 잎자루 밑에 작은 돌기가 없으며 수꽃에 대가 없다  ··········································· 649. 국화마