Alycini

Key to species of North American Alycini

(Solenidial numbers concern only adult stages)

1. Chelicerae beak-like, no cheliceral setae ( Figs. 10C; 50E.) ( Pachygnathus Dugès, 1834 View in CoL )............................. 2

- Chelicerae robust, with 1–2 cheliceral setae ( Figs. 1C, 3C, 5A, 8E, 12C, 50B, H, K)................................ 3

2. Dorsum neotrichous; prodorsal setae sparsely ciliated; ridges slightly undulating; 5 solenidia on femora I ( Figs. 10A, 11C).................................................................................... P. americanus sp. nov.

- Dorsum holotrichous ( Fig. 10G) or neotrichous ( Uusitalo 2010: figs. 53, 61); prodorsal setae strongly ciliated ( Fig. 50D, Uusitalo 2010: fig. 60); ridges slightly undulating and 2 solenidia on femora I ( Fig. 50D, Uusitalo 2010: fig. 56) or ridges strongly undulating and 5–7 solenidia on femora I ( Uusitalo 2010: figs. 60, 64).................. Fauna of the Old World

3. Cheliceral shafts elongated, evenly tapering ( Figs. 12C, 50H, K)................................................ 4

- Cheliceral shafts abruptly tapering into chelae ( Figs. 1C, 3C, 5A, 8E, 50B)........................................ 7

4. Naso absent; setae vi inserted exceptionally closely to each other; prodorsal setae (vi, sce, and exp) reduced in size compared to dorsal setae; anal area caudal; legs II–IV short and usually bent ( Figs. 16A, B, 54, Uusitalo 2010: figs. 82–84, 86, Uusitalo et al. 2020: figs. 76, 77). ( Orthacarus Zachvatkin, 1949 View in CoL )........................................................ 5

- Naso present; setae vi spaced as far or further apart than sensilla ve and setae in from their opposite pairs; prodorsal setae (vi, sce and exp) resemble dorsal setae; anal area ventral; legs II–IV normal in shape and size ( Figs. 12A–C, E, 14A, B, E, 50G, Uusitalo et al. 2020: figs. 31, 32, 51, 65,66). ( Amphialycus Zachvatkin, 1949 View in CoL )..................................... 6

5. Both pairs of prodorsal sensilla (ve and sci) filamentous; cheliceral setae inserted abaxially; 4 palpal eupathidia basally fused together ( Figs. 16A, B, G, 50J–L)................................................... O. oblongus (Halbert, 1920) View in CoL

- Both pairs of prodorsal sensilla gradually widening towards apex; cheliceral setae inserted dorsally; palpal eupathidia inserted exceptionally closely to each other but still separate ( Fig. 54)....................................................................... (Undescribed Orthacarus sp. from South Africa, see Remarks under Orthacarus Zachvatkin, 1949 View in CoL )

6. Naso cone-shaped, longitudinally striated; two pairs of cheliceral setae, anterior pair smooth, posterior pair forked; genital setae 35–45 per valve; tarsus II with 1 solenidion ( Figs. 12A, C, D, 13B)........................ A. holarcticus Uusitalo, 2020

- Naso flap-like, round anterior rim with grainy texture, short lines longitudinally; one pair of smooth cheliceral setae abaxially; genital setae 19–21 per valve; tarsus II with 2 solenidia (14A, C, D, 15B)........................... A. walteri sp. nov.

7. Eyes present; dorsum neotrichous; chelicera with a few teeth ( Figs. 1A–C; 3A–C, 5A, 50A, B). Alycus C.L. Koch, 1842 View in CoL ... 8

- Eyes absent; dorsum holotrichous; chelicera with ca. 20 teeth ( Figs. 7A, B, 8F, 9C, D)............................................................................................... Odontoalycus exoculo gen. nov. and sp. nov.

8. Naso present ( Figs. 1A, 3A)............................................................................ 9

- Naso absent ( Figs. 5A, 6A, B, 50A)............................................... A. denasutus ( Grandjean, 1937) View in CoL

9. Middorsal integument with long, parallel ridges; middorsal setae with a long central point and 5–7 easily distinguishable cilia, caudal setae longest with long cilia resembling prodorsal setae in; coxae IV with 5 setae; femora IV without solenidia ( Figs. 3A, B, 4A, E)........................................................................ A. utahensis sp. nov.

- Middorsal integument with short, irregularly arranged ridges; middorsal setae with a central point and several short cilia, caudal setae with a long central point and much shorter cilia resembling prodorsal setae in; coxae IV with 1–2 setae; femora IV with 1 solenidion ( Figs. 1A, B, 2A, E, Uusitalo 2010: figs. 8–11, 19)............................. A. roseus C.L. Koch, 1842 View in CoL .