Cosmolaelaps, Berlese, 1903

Joharchi, Omid, Döker, Ismail & Khaustov, Vladimir A., 2022, New species and new records of Cosmolaelaps Berlese (Acari: Laelapidae) from Russia, with a review of the Russian species of the genus, Zootaxa 5133 (4), pp. 486-508 : 504-505

Key to species of Cosmolaelaps occurring in the Russia

1. Dorsal setae spatulate with a small basal protuberance........................................................ 2

– Dorsal setae in other forms (e.g., cuneiform, lancet, knife or scimitar-like)........................................ 3

2. Anal shield nearly rounded (semi-circular anterior margin), wider than long, anus small, length of anal shield exceeding length of anal opening by 6 or more times.............. Cosmolaelaps claviger ( Berlese, 1883) [= C. bregetovae Pirianyk, 1959 ]

– Anal shield nearly subtriangular, as long as wide, anus normal, length of anal shield exceeding length of anal opening by 3-4 times........................................................................ C. rectangularis Sheals, 1962

3. Dorsal setae cuneiform................................................................................ 4

– Dorsal setae lancet, knife or scimitar-like.................................................................. 5

4. Post-anal seta spatulate ..................................................... C. neocuneifer ( Evans & Till, 1966)

– Post-anal seta simple............................................................ C. cuneifer ( Michael, 1891)

5. Dorsal setae slender, lancet-like, with small basal protuberance................................................ 6

– Dorsal setae relatively expanded, knife or scimitar-like, with conspicuous basal protuberance......................... 9

6. Movable digit with normal two teeth...................................................................... 7

– Two teeth of movable digit separated by a row of smaller teeth....................................................... C. gryllotalpae ( Berlese, 1910) [= H. elongatus , C. acutiscutus , C. subacutiscutus , C. mirificus and C. angustiscutatus ]

7. Dorsal shield with 37 pairs of setae (z3 and s1 absent) ..................................... C. acuta ( Michael, 1891)

– Dorsal shield with 39–40 pairs of setae.................................................................... 8

8. Dorsal shield with 39 pairs of setae (including two pairs of Zx setae) ................... C. lutegiensis ( Shcherbak, 1971a)

– Dorsal shield with 40 pairs of setae (including three pairs of Zx setae) ................. .. C. markewitschi ( Pirianyk, 1959)

9. Dorsal shield with very long setae, almost all setae reaching well past base of following setae (scimitar-like)............ 10

– Dorsal shield setae shorter, at most reaching base of following setae (knife-like) ................................... 12

10. Dorsal shield setae Z5 longer than J5 ............................................................... C. sejongi

– Dorsal shield setae Z5 shorter than J5 (ratio of J5 / Z5 ≈ 1.5)................................................... 11

11. Post-anal seta well thickened, sparsely barbed and apically hook shaped, sternal setae long, extending beyond base of following setae......................................................................... C. latisetis Joharchi sp. nov.

– Post-anal seta slightly thickened, simple, sternal setae short, at most reaching base of following setae ................................................................................................ C. chianensis [= C. hefeiensis ]

12. Femur IV with spatulate setae ........................................................................... 13

– Femur IV without spatulate setae........................................................................ 15

13. Presternal area with two triangular plates and obviously separated from sternal shield.......... C. robustus ( Berlese, 1905)

– Presternal area lightly sclerotised, with a few transverse curved lines and merged to sternal shield, without distinct plates.. 14

14. Dorsal setae relatively short and thin, mostly not reach to base of next setae in series, femora II and IV with spatulate setae..................................... C. vacua ( Michael, 1891) [= H. militiformis Oudemans and H. (C.) serratosimilis]

– Dorsal setae much thicker, mostly long enough to reach base of next setae in series, femora II–IV with spatulate setae............................................................................... C. dendrophilus Davydova, 1977

15. Dorsal setae long enough to reach base of following setae, opisthogastric setae arising on small sclerotised platelets and moderately thick, distance between genital and anal shields is shorter than length of anal shield, anal shield longer than wide .................................................................................................. 16

– Dorsal setae barely reaching more than half of distance of following setae in series, opisthogastric setae thin and without any such small sclerotised platelets, distance between genital and anal shields is about 1.5 times the length of anal shield, anal shield wider than long ...................................................... .. Cosmolaelaps mixta ( Shcherbak, 1971b)

16. Genital shield tapering posteriorly, anterior margin of sternal shield with a median notch, fixed digit of chelicera with three teeth.............................................................................. C. siberiensis Joharchi, 2019

– Genital shield rounded posteriorly, anterior margin of sternal shield hardly conspicuous, fixed digit of chelicera with six various size of teeth............................................................... .. C. lasiophilus Joharchi sp. nov.