Pseudanisentomon, Zhang and Yin, 1984

Nakamura, Osami, 2021, Three New Species of the Family Eosentomidae (Protura) from the Nasu Imperial Villa, Central Japan, Species Diversity 26 (1), pp. 111-125 : 124

Key to species of Pseudanisentomon

1. Abdominal sternite VIII with single row of seven posterior setae... P. dolichempodim (Yin and Zhang, 1982)

– Abdominal sternite VIII with double rows of two anterior and seven posterior setae..................... 2

2. Abdominal sternites IX–X with six setae............ 3

– Abdominal sternites IX–X with four setae.......... 15

3. Abdominal tergite VII with three pairs of anterior setae (A2, 4, and 5); foretarsal seta x absent............................................. P. villaticum sp. nov.

– Abdominal tergite VII with four pairs of anterior setae (A1, 2, 4, and 5); foretarsal seta x present............ 4

4. Abdominal tergites II–III with four pairs of anterior setae (A1, 2, 4, and 5)............................ 5

– Abdominal tergites II–III with five pairs of anterior setae (A1, 2, 3, 4, and 5).......................... 6

5. Foretarsal sensillum b ′ 1 absent; empodia of middle and hind tarsus long..... P. songkiangensis (Yin, 1977)

– Foretarsal sensillum b ′ 1 present; empodia of middle and hind tarsus short...... P. trilinum (Zhang and Yin, 1981)

6. Abdominal tergite IV with four pairs of anterior setae (A1, 2, 4, and 5)................................. 7

– Abdominal tergite IV with five pairs of anterior setae (A1, 2, 3, 4, and 5)............................... 8

7. Pseudoculus with striae and two beads; foretarsal sensillum b ′ 1 absent... P. sininotialis Zhang and Yin, 1984

– Pseudoculus with striae but without beads; foretarsal sensillum b ′ 1 present........ P. jiangxiensis Yin, 1987

8. Foretarsal sensillum b ′ 1 absent.... P. nasuense sp. nov.

– Foretarsal sensillum b ′ 1 present................... 9

9. Foretarsal sensillum b ′ 1 nearer to δ3 ′ than to δ4 ′... 10

– Foretarsal sensillum b ′ 1 halfway between δ3 ′ and δ4 ′ .............................................. 14

10. Labral setae absent; empodium on the middle tarsus less than 1/5 of claw length....... P.donan Nakamura, 2010

– Labral setae present; empodium on the middle tarsus longer than 1/3 of claw length.................... 11

11. Foretarsus less than 70 µm....................... 12

– Foretarsus longer than 90 µm..................... 13

12. Pseudoculus without striae; foretarsal sensillum c ′ longer than t3 ............... P.parvum Nakamura, 2010

– Pseudoculus with striae; foretarsal sensillum c ′ shorter than t3 .................. P. minystignum (Yin, 1979)

13. Pseudoculus with two or five striae; foretarsal sensillum a halfway between γ1 and γ2 ....... P. meihwa (Yin, 1965)

– Pseudoculus with five striae and three beads; foretarsal sensillum a nearer to γ1 than to γ2 ............................................. P. wanense Zhang, 1987

14. Labral setae present; empodium on the middle tarsus about 1/5 of claw length...... P. ishiii Nakamura, 1996

– Labral setae absent; empodium on the middle tarsus about 1/3 of claw length...... P. babai (Imadaté, 1964)

15. Empodia of middle and hind tarsus longer than 1/3 of claw length.................................... 16

– Empodia of middle and hind tarsus less than 1/5 of claw length.................................... 20

16. Foretarsal sensillum b ′ 1 absent................... 17

– Foretarsal sensillum b ′ 1 present.................. 18

17. Pseudoculus simple; abdominal tergite IV with five pairs of anterior setae (A1, 2, 3, 4, and 5)............................ P. guangxiensis (Yin and Zhang, 1982)

– Pseudoculus with three striae; abdominal tergite IV with four pairs of anterior setae (A1, 2, 4, and 5)...................... P. huichouense Zhang and Yin, 1984

18. Foretarsal sensillum c ′ present; abdominal tergite II with four pairs of anterior setae (A1, 2, 4, and 5)............................... P. sheshanensis (Yin, 1965)

– Foretarsal sensillum c ′ absent; abdominal tergite II with five pairs of anterior setae (A1, 2, 3, 4, and 5)... 19

19. Pseudoculus simple; foretarsal sensillum c ′ present........................ P. molykos Zhang and Yin, 1984

– Pseudoculus with three striae; foretarsal sensillum c ′ absent... P. cangshanense Imadaté, Yin, and Xie, 1995

20. Abdominal tergite III with five pairs of anterior setae (A1, 2, 3, 4, and 5).............................. 21

– Abdominal tergite III with four pairs of anterior setae (A1, 2, 4, and 5)................................ 22

21. Pseudoculus simple; foretarsal sensillum b ′ 1 absent............... P. paurophthalmum Zhang and Yin, 1984

– Pseudoculus with three long and two short striae; foretarsal sensillum b ′ 1 present.................................... P. lishuiensis Bu, Gao, and Luan, 2020

22. Pseudoculus without inner structure; abdominal tergite II with four pairs of anterior setae (A1, 2, 4, and 5)............... P. pedanempodium (Zhang and Yin, 1981)

– Pseudoculus with inner structure; abdominal tergite II with five pairs of anterior setae (A1, 2, 3, 4, and 5)... 23

23. Pseudoculus with “#” like striae; foretarsal sensillum c ′ absent.................... P. yongxingense Yin, 1988

– Pseudoculus with a central bead; foretarsal sensillum c ′ present.......... P. yaoshanensis Zhang and Yin, 1984