Cryophilic Isotomidae (Collembola) of the Northwestern Rocky Mountains, U. S. A. Author Fjellberg, Arne text Zootaxa 2010 2513 27 49 journal article 10.5281/zenodo.196078 3afa748f-2467-40ae-83ec-00984bfe7362 1175-5326 196078 Desoria olympica sp. n. ( Figs. 71–76 ) Type material (all in slides). Holotype (male) and 10 paratypes (in 4 slides) from " USA , Washington, Olympic National Park, Hurricane Ridge 47o59'N , 123o31'W , 10.IX.1983 . Wet moss at snow edge, 1,800 m ., A. Fjellberg 422/83" ( INHS ). Description . Size up to 1.0 mm. Colour white, eye-spots black. Body shape as in two previous species, abd. 5–6 weakly separated. Characters of ocelli, labrum, labial and maxillary palps, maxillae and mandibles as in previous two species. PAO roundish, the size of a ocellus ( Fig. 75 ). Frontoclypeal field with three setae ( Fig. 76 ). Ant. 1 with only two ventroapical short sensilla in addition to a few setaceous ones, ant. 2–3 with only the standard set of sensilla. Ventromedian field of labium with 4 setae. Head with 3+3(4) postlabial setae. Body integument smooth; setal cover sparse and uniform. Macrochaetae distinct, smooth. Median macrochaetae on abd. 5 about 2.7 times as long as inner edge of last claw. Number of ordinary sensilla on tergites as 22/11135 ( Fig. 71 ). Microsensilla as 11/001. Posterior sensilla on th. 2–abd. 4 set in the p-row; no ordinary sensillum laterally to the spine-like ms on abd. 3. Ventral tube with only 1+1 frontal setae; retinaculum with only two setae ( 10 specimens examined); ventral central field of manubrium with fewer than 20 setae ( Fig. 74 ); dens with 7 dorsal setae; mucro 5-toothed ( Fig. 73 ). Inner side of tib. 1-2 with three pairs of setae along median line ( Fig. 72 ). Males present, reproductive specimens not seen. Etymology. Named after the type locality, the Olympic National Park. Discussion . The character which immediately identifies olympica is the reduced number of tergal sensilla (22/11135), which is probably the lowest number observed in any Desoria . Unlike the two previous species the posterior sensilla on th. 2–abd. 4 are set in the p-row. It also differs by the reduced number of antennal sensilla and the low number of setae on ventral tube and retinaculum ( Table 1 ). Distribution and ecology. This distinct species is only known from the type series which appeared in a wet snow edge community in the coastal mountains above Port Angeles, Washington.