Blattisocius

Britto, Erika P. J., Lopes, Paula C. & De, Gilberto J., 2012, Blattisocius (Acari, Blattisociidae) species from Brazil, with description of a new species, redescription of Blattisocius keegani and a key for the separation of the world species of the genus, Zootaxa 3479, pp. 33-51 : 49

Key of species of Blattisocius of the world

Blattisocius urticana ( Nesbitt, 1954) was not included because the females of this species have not been described.

1. Dorsal shield with 31 pairs of setae (z1 absent)............. Blattisocius apisassociae Chinniah & Mohanasundaram, 1995

- Dorsal shield with 32 or more pairs of setae (z1 present)..................................................... 2

2. Ventrianal shield with three pairs of pre-anal setae........................................................... 3

- Ventrianal shield with four pairs of setae pre-anal............................................................ 9

3. Chelicera with movable and fixed digits of similar lengths.................................................... 4

- Chelicera with movable digit much longer than fixed digit..................................................... 6

4. Peritreme long, extending to level of anterior margin of coxa I; ventrianal shield roughly triangular...................................................................................... Blattisocius daci ( Narayanan & Ghai, 1961)

- Peritreme short, extending at most to level of posterior margin of coxa III; shield ventrianal roughly pentagonal.......... 5

5. Dorsal shield mostly smooth, with few transverse striae in opisthonotal region; s2 inserted on dorsal shield; JV4 absent....................................................................... Blattisocius capsicum Basha & Yousef, 2000

- Dorsal shield reticulate; seta s2 inserted on unsclerotised cuticle; JV4 present.................... Blattisocius everti n. sp.

6. Movable cheliceral digit only with apical tooth................................. Blattisocius patagiorum Treat, 1966

- Movable cheliceral digit with one or more teeth in addition to apical tooth........................................ 7

7 Peritreme long, extending to level of posterior margin of coxa II................... Blattisocius tarsalis ( Berlese, 1918)

- Peritreme short, extending to level of posterior margin of coxa III............................................... 8

8. Dorsal shield with transverse striae; fixed cheliceral digit with two teeth in addition to apical tooth.......................................................................................... Blattisocius apis Basha & Yousef, 2000

- Dorsal shield reticulate; fixed cheliceral digit with three teeth in addition to apical tooth..... Blattisocius keegani Fox, 1947

9. Movable cheliceral digit only with apical tooth............................................................. 10

- Movable cheliceral digit with one or more teeth in addition to apical tooth....................................... 11

10. Seta st4 inserted on sternal shield; dorsal setae only slightly surpassing bases of corresponding subsequent setae.................................................................................... Blattisocius edentata ( Karg, 1976)

- Seta st4 inserted on unsclerotised cuticle; dorsal shield setae long, some reaching bases of respective subsequent setae.................................................................. Blattisocius aegypticus Nasr, Nawar & Afifi, 1988

11. Setae st3 and st4 of each side inserted on a platelet attached by a narrow bridge to postero-lateral angle of sternal shield.. 12

- Seta st3 inserted on sternal shield and st4 inserted on unsclerotised cuticle...................................... 14

12. Fixed cheliceral digit with one tooth in addition to apical tooth................. Blattisocius incisus Bhattacharyya, 1977

- Fixed cheliceral digit with three or more teeth in addition to apical tooth........................................ 13

13. Fixed cheliceral digit with three teeth in addition to apical tooth; movable digit with one tooth in addition to apical tooth; j3, j6, J2 and Z4 at most slightly longer than distance to corresponding subsequent seta..... Blattisocius dentriticus ( Berlese, 1918)

- Fixed cheliceral digit with more than ten teeth in addition to apical tooth; movable digit with two teeth in addition to apical tooth; j3, j6, J2 and Z4 at least 1.5 times as long as distance to corresponding subsequent setae.................................................................................................... Blattisocius dolichus Ma, 2006

14. Dorsal shield setae long, surpassing bases of corresponding subsequent setae; st3 inserted into a pair of platelets separated from main body of sternal shield; movable cheliceral digit with three teeth in addition to apical tooth........................................................................................ Blattisocius quadridentatus Haines, 1978

- Dorsal shield setae short, not reaching bases of corresponding subsequent setae; st3 inserted on sternal shield; movable chelic- eral digit with two teeth in addition to apical tooth......................................................... 15

15. Seta Z5 about 1.6 times as long as distance between their bases; with one pair of large and wedge-shaped metapodal shields..................................................................... Blattisocius changjiangensis ( Ma, 2006)

- Seta Z5 about 0.9 times as long as the distance between their bases; with 2 pairs of small, club-shaped metapodal shields............................................................................ Blattisocius mali ( Oudemans, 1929)