Halozercon

Marchenko, Irina I., 2021, Four new species of Halozercon (Acari: Mesostigmata: Zerconidae) from South Siberia Mountains (Russia) with a key to all known species, Zootaxa 4941 (2), pp. 151-185 : 180

Key to the species of the genus Halozercon

1. Central region of opisthonotum raised in the form of a hump; marginal setae very long, plumose, inserted on very high bases................................................................................. Halozercon aesopi sp. n.

- Opisthonotum without hump; marginal setae moderate length.................................................. 2

2. In female second sternal shield is entire....................................................... H. gryphus sp. n.

- In female second sternal shield is divided in two platelets..................................................... 3

3. Opisthonotum with specific location of J -setae in form of a forked tail............................. ... H. alataus sp. n.

- Opisthonotum with other location of J -setae................................................................ 4

4. Some dorsal setae (except marginal) leaf-shaped or lanceolate.................................................. 5

- Dorsal setae (except marginal) other shape................................................................. 6

5. Median region of opisthonotal shield with 17–22 setae of J -series; peritremes of deutonymph shorter than adult: in adult peritremes reaching spine top of II coxae anteriorly, in deutonymph those reaching middle of II coxae. H. tigerek Marchenko, 2019

- Median region of opisthonotal shield with 12–13 setae of J -series; peritremes of adult and deutonymph equal length—reaching level of spine top of coxae II anteriorly............................................. H. barguzin Marchenko, 2018

6. Median region of opisthonotal shield with linear reticulation.......................... H. capitaneus Marchenko, 2019

- Median region of opisthonotal shield ornamented by tubercles.................................................. 7

7. Median region of opisthonotum ornamented by enlarged tubercles fused together in a reticulation pattern.... H. kumir sp. n.

- Median region of opisthonotum ornamented by small, separated tubercles........................................ 8

8. Vertex with pairs of j1, z1 setae and pore ip1 grouped closely together in anterior margin of shield; dorsal setae long and curved; ventri-anal shield with incisions extending to posterior edge of anal opening; male chelicera as in female, fixed digit with five teeth........................................................................ H. kazachok Marchenko, 2019

- Vertex with pairs of j1 and z1 setae, located far from each other and pore ip1 between them; dorsal setae short and straight; ventri-anal shield with incisions extending to anterior edge of anal opening; male chelicera with two basal and 5–6 small distal teeth on fixed digit...................................................... H. karacholana Wiśniewski et al. 1992