꼭두서니과 Rubiaceae

1. 초본식물이다.

2. 씨방은 각 실에 많은 종자가 들어있다 ······························································································ 낚시돌풀속

2. 종자는 각실에 1개씩 들어있다.

3. 잎은 대생한다 ······················································································································· 401. 백령풀

3. 잎은 윤생한 것처럼 보인다.

4. 꽃부리밑은 통상이다 ················································································································ 선갈퀴속

4. 꽃부리는 밑부분이 종처럼 생겼다.

5. 열매는 장과로서 꽃의 부분은 5수이다 ························································································꼭두서니속

5. 열매는 건과로서 꽃의 부분은 4수이다 ·····························································································갈퀴속

1. 목본식물이다.

6. 씨방은 각실에 밑씨가 많이 들어있다.

7. 꽃은 두상으로 달리고 열매는 건과이다···················································································  402. 중대가리나무

7. 꽃은 1 개씩 액생한다 ············································································································· 403. 치자나무

6. 씨방은 각 실에 밑씨가 1개씩 들어있다.

8. 덩굴식물이다.

9. 낙엽성이다 ······················································································································   407. 계요등

9. 상록성이다·······················································································································408. 호자덩굴

8. 곧추자란다.

10. 꽃의 부분은 5수이고 가시가 없다.

11. 단지가 없고 잎은 길이 8 cm 이상이다  ···············································································405+. 무주나무

11. 단지가 있고 잎은 길이 2 cm 내외이다···················································································   433. 백정화

10. 꽃의 부분은 4 수이고 가시가 있다 ·····························································································호자나무속

치자나무속 Gardenia ELLIS

  1. 잎은 길이 4~8cm 이고 너비 1~2cm 이다 ····························································································404. 꽃치자

  1. 잎은 길이 3-15 cm 이다 ··············································································································403. 치자나무