Protoribates, Berlese, 1908

Chen, Shujing Xu Yannan & Chen, Jun, 2020, New species and records of oribatid mites of the genus Protoribates (Acari Oribatida, Haplozetidae) from China, Zootaxa 4772 (3), pp. 469-511 : 506-507

Key to the Chinese species of the genus Protoribates

1. Adanal setae ad 1 barbed, ad 2 smooth; ad 1 longer and thicker than ad 2 ............................................ 2

- Both adanal setae ad 1 and ad 2 smooth or barbed; ad 1 not longer and thicker than ad 2 ................................ 3

2. Bothridial setae setiform; distance between notogastral porose areas A1–A1 shorter than A2–A2; notogastral setae lp inserted posteriorly or posteromedially to A1; body size: 505 × 285.................... P. varisetiger ( Wen, Aoki & Wang, 1984)

- Bothridial setae with slightly unilaterally dilated head; distance between notogastral porose areas A1–A1 subequal to A2–A2; notogastral setae lp inserted anteromedially to A1; body size: 470–650 × 275–382.............. P. dentatus ( Berlese, 1883)

3. Lamellar setae le distinctly thicker than rostral setae ro and interlamellar setae in, like tusk (see fig. 13); body size: 469–509 × 302–375............................................................. P. crassisetiger nipponicus Fujita, 1989

- Lamellar setae le similar to or slightly narrower than rostral setae ro and interlamellar setae in in thickness.............. 4

4. Legs monodactylous................................................................................... 5

- Legs heterotridacylous................................................................................ 10

5. Notogastral setae long (more than 30 μm) and barbed (except setae c, short and smooth) (see fig. 1); body size: 520–700 × 310–460............................................................................. P. tibetensis sp. nov.

- Notogastral setae short or minute (less than 20 μm), smooth................................................... 6

6. Lamellar setae le shorter than or similar to notogastral setae; anterior notogastral margin fine......................... 7

- Lamellar setae le longer than notogastral setae; anterior notogastral margin distinct................................. 8

7. Bothridial setae seriform or with slightly unilaterally dilated head (see fig. 23); body size: 315–460 × 144–225............................................................................... P. cattienensis Ermilov & Anichkin, 2011

- Bothridial setae with unilaterally dilated head (see fig. 15); body size: 400–430 × 184–200........ P. geonjiensis Choi, 1994

8. Bothridial setae setiform; adanal setae ad 1 and ad 2 barbed; custodium present; body size: 525–565 × 300–330....................................................................................... P. lophothrichus ( Berlese, 1904)

- Bothridial setae with unilaterally dilated, barbed head; adanal setae ad 1 and ad 2 smooth; custodium absent............... 9

9. Adanal setae ad 1 and ad 2 distinctly longer than anal setae; lamellar setae le barbed, longer than their mutual distance, inserted on lamellar ends; dorsophragmata comparatively short; body size: 385–560 × 185–325.......... P. oblongus (Ewing, 1909)

- Adanal setae ad 1 and ad 2 similar to anal setae in length; lamellar setae le smooth, short, usually not more than half of their mutual distance, inserted medially to lamellar ends; dorsophragmata comparatively long; body size: 320–440 × 238–266.................................................................................... P. capucinus Berlese, 1908 *

10. Adanal setae ad 1 and ad 2 distinctly longer than anal setae..................................................... 11

- Adanal setae ad 1 and ad 2 similar to anal setae in length....................................................... 12

11. Adanal setae ad 1 1.3–1.6 × their mutual distance; femora II ventroanteriorly pointed; notogastral porose areas A1 occasionally divided into two pores on both sides or on one side; body size: 660–872 × 440–620............... P. magnus ( Aoki, 1982)

- Adanal setae ad 1 less than 1.0 × their mutual distance; femora II ventroanteriorly rounded; notogastral porose areas A1 not divided; body size: 520–660 × 320–400................................................. P. sichuanensis sp. nov.

12. Genital setae four pairs; body size: 390–425 × 180–185.......................... P. tenuis ( Wen, Aoki & Wang, 1984)

- Genital setae five pairs................................................................................ 13

13. Notogastral setae eight pairs; interlamellar setae in and lamellar setae le longer than bothridial setae; distance between notogastral porose areas A1–A1 subequal to A2–A2 ............................................. P. urbanlus ( Tseng, 1984)

- Notogastral setae ten pairs; interlamellar setae in and lamellar setae le shorter than bothridial setae; distance between notogastral porose areas A1–A1 shorter than A2–A2; body length: 680.............................. P. acutus ( Hammer, 1979)