Key to species of the genus Zetorchella known from the Afrotropical region

1. Notogaster without foveolae, but covered by the tuberculate cerotegument forming specific ornamentation; nine pairs of notogastral setae present (p 3 not developed); body length: 365–415. Distribution: Côte d'Ivoire ….......................... Z. cotedivoirensis Ermilov, 2019

– Notogaster with foveolae and without tuberculate cerotegument; ten pairs of notogastral setae present (p 3 developed) .............................................................................................. 2

2. Dorsal notogastral setae phylliform ..................................................................................... 3

– Dorsal notogastral setae not phylliform ................................................................................ 6

3. Bothridial seta shorter than dorsal notogastral setae, stalk shorter than head; notogastral setae p 2 and p 3 shorter and narrower than others; body length: 397–494. Distribution: Senegal .................................................................................... Z. rugosa (Mahunka, 1992)

– Bothridial and dorsal notogastral setae similar in length, stalk not shorter than head; notogastral setae p 2 and p 3 not shorter and not narrower than others ....................................... 4

4. Interlamellar seta phylliform, similar in length to all notogastral setae; genital plate not striate; body length: 408–520. Distribution: Afrotropical region ...................................... .................................... Z. pedestris Berlese, 1916 (= Chaunoproctus crinitus Karppinen, 1966; = Caloppia papillata Balogh, 1958)

– Interlamellar seta thickened or slightly phylliform, distinctly longer than all notogastral setae; genital plate longitudinally striate ..................................................................................... 5

5. Bothridial and notogastral setae slightly differs in length; notogaster with sinuous ridges; anogenital region heavily foveate; anal plate foveolate; body length: 796–898. Distribution: Ethiopia .............................................................. Z. arsiensis Ermilov, sp. n.

– Bothridial seta distinctly longer than all notogastral setae; notogaster without sinuous ridges; anogenital region foveolate; anal plate foveate-reticulate; body length: 481–614. Distribution: Ethiopia ............ Z. robertbecki Ermilov, Subías, Shtanchaeva et Friedrich, 2021

6. Bothridial seta bacilliform; body length: 785–830. Distribution: Zimbabwe ...................... .......................................................................................... Z. longipilosa (Mahunka, 1973)

– Bothridial seta clavate .......................................................................................................... 7

7. Notogastral setae (except c) uniformly flattened, bilaterally densely serrated; body length: 564–630. Distribution: Ghana ......................... Z. ghanaensis Ermilov et Bąkowski, 2021

– All notogastral setae not uniformly flattened, bilaterally densely serrated .......................... 8

8. Stalk of bothridial seta shorter than head; notogastral setae p 2 and p 3 bacilliform; body length: 394. Distribution: Madagasсar ............................ Z. semirugosa (Mahunka, 2011)

– Stalk of bothridial seta longer than head; notogastral setae p 2 and p 3 setiform .................... 9

9. Notogastral seta c longer than bothridial seta; body length: 837. Distribution: Afrotropical region ........................................................................................... Z. vargai (Balogh, 1959)

– Notogastral seta c shorter than bothridial seta .................................................................... 10

10. Notogastral seta c slightly shorter than bothridial seta and distinctly longer than notogastral setae p 2 and p 3; body length: 713–813. Distribution: Ethiopia ......................................... ................................................................ Z. nortoni Ermilov, Sidorchuk et Rybalov, 2010

– Notogastral seta c distinctly shorter than bothridial setae and similar in length to notogastral setae p 2 and p 3 .................................................................................................................. 11

11. Anterior notogastral margin well-developed medially; notogastral setae rod-like; body length: 590–600. Distribution: Congo, India ...................... Z. basilewskyi (Balogh, 1958)

– Anterior notogastral margin not observed medially; notogastral setae bacilliform; body length: 465. Distribution: Afrotropical region, India ................... Z. minor (Balogh, 1958)