Two new species of Ologamasus (Acari: Mesostigmata: Ologamasidae) from Brazil with a key to the world species of the genus Author Santos, Jandir C. Author Castilho, Raphael C. Author Silva, Edmilson S. Author De Moraes, Gilberto J. text Zootaxa 2015 4058 2 267 277 journal article 39256 10.11646/zootaxa.4058.2.8 965dad39-63e3-429c-beb2-916f4deb3d07 1175-5326 244241 4C0A5AD2-80F9-4916-9010-5A55D90096AA Key to world species of Ologamasus , based on adult females 1. Most dorsal idiosomal setae spatulate and pilose............................................................. 2 - Most dorsal idiosomal setae aciculate and smooth ( Fig. 5 )..................................................... 7 2. Anterior margin of epistome with a median extension flanked by one or two pairs of spine-like extensions.............. 3 - Anterior margin of epistome only with a median extension.................................................... 5 3. Dorsal idiosomal shield with 30 pairs of setae................ Ologamasus simplicitus Karg & Schorlemmer, 2009 ; Brazil - Dorsal idiosomal shield with 40-41 pairs of setae............................................................ 4 4. Setae J 3 and J 4 as long as distance between their bases and bases of subsequent J setae; seta Z 5 about 1.6 times as long as J 5.................................................... Ologamasus cananeiae Silva, Moraes & Krantz, 2007 ; Brazil - Setae J 3 and J 4 at least 1.2 times as long as distance between their bases and bases of subsequent J setae; seta J 5 as long as Z 5..................................................................... Ologamasus foliatus Karg, 1976a ; Chile 5. Para-anal seta about twice as long as J v5. ............... Ologamasus trituberculatus Karg & Schorlemmer, 2009 ; Brazil - Para-anal seta about as long as Jv5....................................................................... 6 6. Seta Jv 4 about 0.5 times as long as distance between its base and base of Jv 5........................................................................................... Ologamasus brevidigitus Karg & Schorlemmer, 2009 ; Brazil - Seta Jv 4 about as long as distance between its base and base of Jv 5.......... Ologamasus aberrans ( Berlese, 1888 ) ; Brazil 7. Dorsal shield J setae at most 0.8 times as long as distance between their bases and bases of subsequent J setae........... 8 - Dorsal shield J setae at least as long as distance between their bases and bases of subsequent J setae.................. 12 8. Ventrianal shield fused with dorsal shield only by a narrow area posterior to anus..................................................................................... Ologamasus brevisetosus Karg & Schorlemmer, 2009 ; Ecuador - Ventrianal shield totally fused with dorsal shield, except anterolaterally.......................................... 9 9. Dorsal idiosomal setae minute (2–4 µm)............................ Ologamasus microcrinis ( Karg, 1979 ) ; Argentina - Dorsal idiosomal setae short, but not minute (≥ 10 µm)...................................................... 10 10. Posterior margin of genital shield truncate; ventrianal shield smooth............ Ologamasus distorta ( Karg, 1976a ) ; Chile - Posterior margin of genital shield convex; ventrianal shield striate............................................. 11 11. Ventrianal shield with eight pairs of setae ( Jv 2 present)................... Ologamasus lanceolatus ( Karg, 1976a ) ; Chile - Ventrianal shield with seven pairs of setae ( Jv 2 absent)..................... Ologamasus cavei Sheals, 1962 ; Argentina 12. Ventrianal shield fused with dorsal shield only by a narrow area posterior to anus................................. 13 - Ventrianal shield totally fused with dorsal shield, except anterolaterally ( Fig. 6 )................................... 17 13. Ventrianal shield with seven pairs of setae ( Zv 3 present)................. Ologamasus membranosus Karg, 1976a ; Chile - Ventrianal shield with six pairs of setae ( Zv 3 absent)........................................................ 14 14. Opisthonotal region of dorsal idiosomal shield with 20 pairs of setae ( R 1- R 5 present).............................. 15 - Opisthonotal region of dorsal idiosomal shield with 16 pairs of setae ( R 1- R 4 absent)............................... 16 15. Setae j 6 and J 1 respectively at most 0.9 times as long as distance between their bases and bases of J 1 and J 2; ventrianal shield smooth...................................................... Ologamasus striolatus ( Berlese, 1916 ) ; Argentina - Setae j 6 and J 1 respectively at least 1.5 times as long as distance between their bases and bases of J 1 and J 2,; ventrianal shield imbricate....................................................... Ologamasus striolatosimilis Karg, 1976a ; Chile 16. Reticulation of dorsal idiosomal shield with transversally elongate cells; podonotal region of dorsal idiosomal shield with 21 pairs of setae ( s 1, s 4 and r 1 absent); sternal shield reticulate..... Ologamasus postpilus Karg & Schorlemmer, 2009 ; Brazil - Reticulation of dorsal idiosomal shield with roundish cells; podonotal region of dorsal idiosomal shield with 20 pairs of setae ( s 1, s 4, r 1 and r 2 absent); sternal shield longitudinally striate. Ologamasus latoventer Karg & Schorlemmer, 2009 ; Paraguay 17. Anterior margin of epistome convex and denticulate; genital shield wider than long (including membranous flap); ventrianal shield with seven pairs of setae (not bearing Jv 5)......................... Ologamasus testudinis ( Karg, 1976b ) ; Chile - Anterior margin of epistome with a median extension variously denticulate ( Fig. 3 ); genital shield as long as wide (including membranous flap) ( Fig. 6 ); ventrianal shield with eight pairs of setae (bearing Jv 5) ( Fig. 6 )......................... 18 18. Sternal shield imbricate; genital shield striate laterally, smooth elsewhere; unsclerotised strip of integument separating ventria- nal from dorsal shield extending to region between Zv 2 and Zv 3 ( Fig. 18 )........... Ologamasus delaliberai n. sp. ; Brazil - Sternal shield reticulate near st 1 and with longitudinal and parallel striae elsewhere; genital shield striate; unsclerotised strip of integument separating ventrianal from dorsal shield extending almost to Jv 5..................................... 19 19. Podonotal region of dorsal idiosomal shield with 21 pairs of setae ( s 1, s 4 and r 1 absent); opisthonotal region of dorsal idio- somal shield with 20 pairs of setae ( Z 4 and R 5 present); setae Jv 3 and Zv 2 at least as long as distance between their bases and bases of Jv 4 and Zv 3 respectively................................. Ologamasus simplicior ( Berlese, 1914 ) ; Argentina - Podonotal region of dorsal idiosomal shield with 20 pairs of setae ( z 4, s 1, s 4 and r 1 absent); opisthonotal region of dorsal idio- somal shield with 18 pairs of setae ( Z 4 and R 5 absent) ( Fig. 5 ); setae Jv 3 and Zv 2 at most 0.7 times as long as distance between their bases and bases of Jv 4 and Zv 3 respectively ( Fig. 6 )............................ Ologamasus lucasi n. sp. ; Brazil