Myrmozercon, Berlese, 1902

Trach, Viacheslav A. & Khaustov, Alexander A., 2018, The first record of the genus Myrmozercon Berlese (Acari: Mesostigmata: Laelapidae) in the Neotropical region and a description of a new species, Acarologia 58 (1), pp. 41-51 : 48-49

Key to non-Palaearctic species of the genus Myrmozercon (females)

1. Leg setation hypotrichous: leg I (from femur to tibia) 8–8–8, leg II 8–8–7. Palpcoxal setae sometimes absent. Setae st4 usually absent. Anal shield usually with anterolateral extensions........................................................... Myrmozercon sensu stricto – 2

— Leg setation holo- or hypertrichous: leg I (from femur to tibia) at least 11–11–10, leg II at least 9–10–9. Palpcoxal setae present. Setae st4 usually present. Anal shield without anterolateral extensions...................................... Myrmozercon sensu lato – 6

2. Seta j1 not the longest in podonotal part of dorsal shield............................... 3

— Seta j1 the longest in podonotal part of dorsal shield.................................. 5

3. Coxa IV without setae; trochanter III with 5 setae. Most dorsal setae barbed [ Yemen]..................................................... M. yemeni ( Ueckermann and Loots, 1995)

— Coxa IV with 1 seta; trochanter III with 4 setae. All dorsal setae smooth................ 4

4. Dorsal shield with 38 pairs of setae, posterior dorsal setae spine-like. Trochanter II with 5 setae; femur IV with 7 setae; genu IV with 8 setae [ USA]..................................................................................... M. clarus ( Hunter and Hunter, 1963)

— Dorsal shield with 35 pairs of setae, posterior dorsal setae simple. Trochanter II with 4 setae; femur IV with 6 setae; genu IV with 7 setae [ USA]........................................................................................ M. spinosus ( Hunter and Hunter, 1963)

5. Opisthonotal part of dorsal shield with 5 or 6 setae longer than others. Body length 561 [ Equatorial Guinea]........................................ M. eidmanni ( Sellnick, 1941)

— Opisthonotal part of dorsal shield with 3 or 4 setae longer than others. Body length 418 – 429 [ Equatorial Guinea]....................................... M. minor ( Sellnick, 1941)

6. Body length less than 1000......................................................... 7

— Body length more than 1300 [East Africa]....................... M. titan (Berlese, 1916) 7. Dorsal shield highly hypertrichous, covered with dense pelage of more than 200 short setae..................................................................................... 8

— Dorsal shield setation hypotrichous to only moderately hypertrichous with a maximum of about 50 pairs of setae................................................................ 9

8. Dorsal shield 850 long. Marginal setae uniformly short [ Australia].................................................................................... M. aequalis ( Banks, 1916)

— Dorsal shield 720 long. Setae fringing posterior margin longer [ Australia]............................................................................ M. scutellatus ( Hull, 1923)

9. Dorsal shield with no more than 30 pairs of setae. Coxae I–III with 2 setae; coxa IV with 1 – 2 setae........................................................................... 10

— Dorsal shield with 39–50 pairs of setae. Coxae I–III with 6 setae; coxa IV with 4 setae [ Australia]..................................................... M. iainkayi Walter, 2003

10. Coxa IV with 2 setae.............................................................11

— Coxa IV with 1 seta.............................................................. 12

11. Setae st4 and st5 present. Anal shield with 5 setae [ USA, imported from Mexico]........ ............................................. M. chapmani (Baker and Strandtmann, 1948)

— Setae st4 and st5 absent. Anal shield with 3 setae [ Australia]........................... ..................................................... M. beardae Shaw and Seeman, 2009

12. Dorsal shield with 24–27 pairs of setae. Ventral soft cuticle holotrichous or hypertrichous, with 9–16 pairs of setae. Peritrematal shields free from dorsal shield. Femur III with 5–6 setae; femur IV with 6–7 setae............................................................. 13

— Dorsal shield with 29–30 pairs of setae. Ventral soft cuticle hypertrichous, with 22–25 pairs of setae. Peritrematal shields fused with dorsal shield. Femur III with 7–8 setae; femur IV with 8 setae [ Chile].................................................... M. patagonicus n. sp.

13. Dorsal shield with 24–25 pairs of setae. Dorsal soft cuticle not hypertrichous, with about 5 pairs of setae. Ventral soft cuticle not hypertrichous, with about 9–11 pairs of setae. Femur II with 11 setae; genu II with 12 setae; tibia II with 10 setae; femur III with 6 setae; tibia III with 9 setae; femur IV with 6 setae; genu IV with 11 setae; tibia IV with 10 setae [ Australia].......................................................... M. burwelli Shaw and Seeman, 2009

— Dorsal shield with 27 pairs of setae. Dorsal soft cuticle hypertrichous, with about 15 pairs of setae. Ventral soft cuticle hypertrichous, with about 16 pairs of setae. Femur II with 9 setae; genu II with 11 setae; tibia II with 11 setae; femur III with 5 setae; tibia III with 10 setae; femur IV with 7 setae; genu IV with 9 setae; tibia IV with 8 setae [ USA]....................................................................... M. rotundiscutum Rosario and Hunter, 1988