Eupterotegaeus, Berlese, 1916

Ermilov, Sergey G., 2024, Ontogenetic instars of the oribatid mite Eupterotegaeus nortoni sp. nov. (Acari, Oribatida, Cepheusidae) from U. S. A., Zootaxa 5485 (1), pp. 49-61 : 60

Key to known species of Eupterotegaeus (adult)

1. Lamellar cusps nearly quadrangular, mediodistally located very close to each other................................. 2

- Lamellar cusps nearly elongate triangular, mediodistally well distanced from each other............................. 3

2. Lamellar cusp with small mediodistal tooth; bothridial seta long, distinctly longer than half of distance between bothridia; body length: 586–599................ E. xizangensis Wang & Solhøy, 2001 (see Wang et al. 2001). Distribution: China (Tibet).

- Lamellar cusp without teeth; bothridial seta comparatively short, not longer than half of distance between bothridia; body length: 785........... E. flavus ( Ewing, 1918) (see also Woolley 1957; Walter et al. 2013). Distribution: U.S.A. (Oregon).

3. Interlamellar tooth absent.............................................................................. 4

- Interlamellar tooth present.............................................................................. 7

4. All legs monodactylous; anterior notogastral margin with a pair of tubercles forming enantiophyses with a posterior tubercle of the bothridium; body length: 396–600.............................................................................................. E. rhamphosus Higgins & Woolley, 1968 (see also Walter et al. 2013). Distribution: Nearctic.

- All legs tridactylous; anterior notogastral margin without a pair of tubercles forming enantiophyses with a posterior tubercle of the bothridium....................................................................................... 5

5. Rostral tooth well developed; lamellar cusp with distal toothlike process; body length: 616–755........................ Eupterotegaeus ornatissimus ( Berlese, 1908) (see also Kunst 1958; Pérez-Iñigo 1997; Walter et al. 2013). Distribution: Holarctic.

- Rostral tooth minute or absent; lamellar cusp without distal toothlike process..................................... 6

6. Rostrum truncate; rostral tooth minute; lamellae distanced from each other; body length: 612............................................................................ E. rostratus Higgins & Woolley, 1963 . Distribution: Nearctic.

- Rostrum rounded; rostral tooth absent; lamellae partially located close to each other; body length: 620–674........................................................... E. hendekensis Susyal, Ayyildiz & Baran, 2018 . Distribution: Turkey.

7. Rostral tooth present.................................................................................. 8

- Rostral tooth absent................................................................................... 9

8. Rostral tooth medium-sized; lamellar cusp without distal toothlike process; notogastral seta c present; body length: 615–630........................................................... E. nortoni sp. nov. Distribution: U.S.A. (New York).

- Rostral tooth small; lamellar cusp with distal toothlike process; notogastral seta c absent; body length: 1030...................................................................... E. steinboecki ( Mihelčič, 1958) . Distribution: Austria.

9. Interlamellar tooth long, extending anteriorly beyond rostrum................................................. 10

- Interlamellar tooth medium-sized, not reaching rostrum..................................................... 11

10. Bothridial seta with large compact head; lamellar cusp with distal toothlike process; notogastral seta c present; body length: 536–645.................................................................................... E. armatus Aoki, 1969 (see also Fujikawa 2002; Walter et al. 2013). Distribution: East of eastern Palaearctic, Southeast China, Costa Rica.

- Bothridial seta with elongate clavate head; lamellar cusp without distal toothlike process; notogastral seta c absent; body length: 691......................................................... E. nasalis Sitnikova, 1979 . Distribution: Ecuador.

11. Rostrum truncate; notogastral seta c present; body length: 558–594..................................................................... E. spinatus Higgins & Woolley, 1963 (see also Walter et al. 2013). Distribution: U.S.A. (Utah).

- Rostrum rounded; notogastral seta c absent; body length: 541–616... E. dentatus Sitnikova, 1979 . Distribution: Neotropical.