Ceratophysella armata (Nicolet, 1842)

Jia, Junli, Zhao, Xuemeng, Skarżyński, Dariusz, Wu, Ruiwen, Cheng, Liping & An, Jianmei, 2024, Morphological description and DNA barcoding of Ceratophysella gracilimucronata sp. nov. (Collembola: Hypogastruridae) from China, with a key to species of the C. armata group of the Sino-Japanese Region, Zootaxa 5432 (4), pp. 555-566 : 563

Key to species of the C. armata group of the Sino–Japanese Region

The key is mainly based on Babenko et al. (1994). Distribution of species in the Sino–Japanese Region (sensu Christiansen & Bellinger 1995, Bellinger et al. 1996 –2024) is presented in Tab. 3 .

1. Ant. IV with strongly bent setae................................................. C. flectoseta Lin & Xia, 1983

- Ant. IV with normal setae.............................................................................. 2

2. Sensillae p 4 on Th. II–III shorter than microsetae.............. C. microchaeta Babenko, 1994 in Babenko et al. (1994)

- Sensillae p 4 on Th. II–III longer than microsetae............................................................ 3

3. Abd. V with medial spine-like tegumentary projection....................................................... 4

- Abd. V without such projection.......................................................................... 5

4. Abd. IV with p 3 setae present...................................................... C. liguladorsi ( Lee, 1974)

- Abd. IV with p 3 setae absent............................ C. mediolobata Nakamori, 2020 in Nakamori et al. (2020)

5. Setae p 1 on Abd. V modified into spines.......................................... C. duplicispinosa ( Yosii, 1954)

- Setae p 1 on Abd. V normal.............................................................................. 6

6. Head with 1 + 1 cornea-like structures in the area frontalis.................................................... 7

- Head without such structures............................................................................ 8

7. Abd. IV with setae p 3 ............................................................... C. sinensis Stach, 1964

- Abd. IV without setae p 3........................................................ C. beatifica Nakamori, 2023

8. Empodial appendage longer than inner edge of claws............ C. empodialis Babenko, 1994 in Babenko et al. (1994)

- Empodial appendage about 1/2 of the inner edge of claws..................................................... 9

9. Dens with large ventro-apical swelling............................................. C. bengtssoni ( Ågren, 1904)

- Dens without distinct swelling......................................................................... 10

10. Mucro short and slender with low outer lamella............................................................ 11

- Mucro spoon shaped, broad at the tip with clear outer lamella................................................. 12

11. Abd. IV without setae p 3, apical vesicle on Ant. IV trilobed, eversible sac between Ant. III and IV present, 20–23 granules between macrosetae p 1 on Abd. V........................................................ C. ainu ( Yosii, 1972)

- Abd. IV with setae p 3, apical vesicle on Ant. IV simple, eversible sac between Ant. III and IV absent, 8–10 granules between macrosetae p 1 on Abd. V........................................................ C. gracilimucronata sp. nov.

12. Tibiotarsal tenent hairs more or less clearly clavate......................................................... 13

- Tibiotarsal tenent hairs acuminate....................................................................... 16

13. Tibiotarsi I–III with one clavate tenent hair............................................................... 14

- Tibiotarsi I–III with two or three clavate tenent hairs........................................................ 15

14. Ant. IV with simple apical vesicle.................................................... C. sigillata ( Uzel, 1891)

- Ant. IV with trilobed apical vesicle.............................................. C. dolsana ( Lee & Kim, 1995)

15. Tibiotarsi Ⅰ–III with 2 clavate tenent hairs........................................ C. biclavata Park & Park, 2006

- Tibiotarsi Ⅰ–III with 3 clavate tenent hairs................................................ C. fujisana Itoh, 1985

16. Spine-like setae on dorsal part of the body present.......................................................... 17

- Spine-like setae on dorsal part of the body absent.......................................................... 18

17. Setae c 3, g 2, g 3, l 0, l 2 on head, setae p 1 and p 3 on Th. II–III and p 1 on Abd. I–III spine-like.......... C. ateruii Tamura, 2001

- Spine-like setae present only on head in positions oc 2 and v 2 ..................... C. wrayia ( Uchida & Tamura, 1968)

18. Anal spines short (ratio: anal spines/claws III = 0.4), claws without inner tooth, Abd. I with microsensillum in position p 7................................................................................ C. sakayorii Tamura, 1997

- Anal spines longer, claws with inner tooth, Abd. I without microsensillum in position p 7 ............................ 19

19. Dens with unmodified setae only....................................................................... 20

- Dens with at least 2 modified setae...................................................................... 21

20. Th. II with setae a 2 subequal with a 1 .......................... C. laricis Martynova, 1977 in Martynova et al. (1977)

- Th. II with setae a 2 longer than a 1 ................................................. C. sinetertiaseta ( Lee, 1974)

21. Abd. IV with setae p 3.............................................................. C. armata ( Nicolet, 1842)

- Abd. IV without setae p 3 .............................................................................. 22

22. Ant. IV with simple apical vesicle and up to 20 peg-like sensilla in ventral file.......................................................................................... C. borealis Martynova, 1977 in Martynova et al. (1977)

- Ant. IV with trilobed apical vesicle and at least 30 peg-like sensilla in ventral file................................. 23

23. Ant. IV with 30–32 peg-like sensilla in ventral file.......... C. skarzynskii Weiner & Sun, 2019 in Weiner et al. (2019)

- Ant. IV with more than 50 peg-like sensilla in ventral file................................. C. denisana ( Yosii, 1956)