가막사리속 Bidens LINN.

1. 수과는 도란상 쐐기형이며 끝아 좁아지지 않는다.

2. 수과는 4 능형이고 끝에 가시가 4 개 있으며 통상 꽃부리는 5 열이다················································· 690. 좁은잎가막사리

2. 수과는 편평하며 가시가 2 개있고(간혹 3-4 개) 꽃부리끝은 4 열한다.

3. 잎은 우상복엽이며 정엽에 대가 있고 두화에는 작은 설싱화가있다 ··················································· 691. 미국가막사리

3. 잎은 우상으로 갈라지고 설상화가 없다

4. 수과는 길이 7-11mm 이다 ···································································································· 692. 가막사리

4. 수과는 길이 4.5-5.5mm 이다 ··························································································· 693. 구와가막사리

1. 수과는 선행이며 끝이 좁아진다

5. 수과에는 2개의 가시가 있고，잎은 2-3회 우상으로 갈라지고 통상화는 4열한다 ············································· 694. 까치발

5. 수과에 3-4 개의 가시가 있고 통상화는 5 열한다.

6. 총포 외편은 숟가락형이다  ······························································································695+. 울산도깨비바늘

6. 총포 외편은 피침형이다.

7. 잎의 정열편은 좁고 끝이 뾰족하며 약간의 톱니가있다···································································695. 도깨비바늘

7. 잎의 정열편은 난형이며 짧게 뾰족하고 톱니가 많다···································································696. 털도깨비바늘