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 cryophila sp. n. ( Figs. 57–63 , 115H ) Type material . Holotype (alc.) and 33 paratypes ( 26 in alcohol, 7 in two slides) from " Canada , Alberta, Kananaskis, French creek, 50o55'N , 134o40'W , 16.VI.1984 . Wet moss at waterfall, 1,930 m . alt., A. Fjellberg leg." ( INHS ). Description. Size up to 1.2 mm . Body shape normal for the genus, with a slightly pear-shaped abdomen. Head normal, not prognathous/hypognathous. Abd. 5–6 fused without distinct break in setal cover. Colour white with black eye-spots ( Fig. 115H ). Ocelli 6+6 (G & H absent), PAO oval, slightly shorter than diameter of nearest ocellus. Three setae associated with PAO ( Fig. 58 ). Ant. 1 ventrally with 4–5 short thick apical sensilla and several slender setaceous sensilla; base with a group of ventral microsensilla ( Fig. 60 ). Ant. 2 with 3–4 small and thin sensilla in lateroapical position ( Fig. 62 ). Ant. 3 organ with some additional setaceous sensilla ( Fig. 61 ). No ventral erect sensilla present on ant. 2–3. Ant. 4 with bifurcate pin seta and a small globular organite in the subapical organ. Labrum with 4/554 normal setae, apical edge with 4 sharp folds and a composite ventral ciliation. Frontoclypeal area with 5–9 setae, two setae between antennal base and labral corner. Maxillary palp bifurcate, four sublobal setae. Labial palps unmodified, complete, guard e7 present; terminal sensilla on the papillae as long as guards; four proximal setae present. Hypostomal group with H as long as h1/h2. Basal fields of labium with 4(5) median and 5 lateral setae. Head with 5–6 postlabial setae. Mandibles normal, strong. Maxillae unmodified, with short denticulate lamellae and 3-toothed capitulum. Body integument smooth. Body with a dense markedly "double" setal cover with short ordinary setae and dagger-like mesochaetae some as long as the erect macrochaetae on thorax and abd. 1 (as Fig. 30 ). Macrochaetae moderately strong on abdomen, distinctly serrated on the last abdominal segments. Median macrochaetae on abd. 5 about 2.5 as long as inner edge of last claw. Sensilla on the tergites hard to see in adults because of dense setal cover, but several half-grown juveniles show distribution as 55/44456 ( Fig. 57 ) with some variation in number on the three last segments; anterior sensilla present on abd. 4–5; spine-like microsensilla distributed as 11/001. Ventral tube on each side with (1)3–5 frontal and up to 15 lateral setae, posterior side with up to 8 setae. Retinaculum with 4+4 teeth and up to 8 setae. Manubrium with blunt apical teeth and 3+3(4) short ventroapical setae; ventromedial field densely pilose, with more than 50 setae. Dens dorsally crenulated, with 12–14 dorsal setae in proximal half and a tiny subapical setula; subapical ventral seta not prolonged. Mucro with 4 sharp primary teeth and a small secondary tooth on the inner side formed by the inner lateral lamella ending before tip of the subapical tooth ( Fig. 59 ); apical and subapical teeth subequal; no lateral seta. Tibiotarsi with 11 apical setae, all acuminate. Legs long and slender, inner side of Tib. 1–2 with 4– 5 setae along each side of median line ( Fig. 63 ). Claws of normal shape, with small laterobasal teeth and a weak tooth in the middle of the inner edge; unguiculus with high basal lamella, usually with a small corner tooth. Males present, reproductive individuals not seen. Etymology . The name reflects the cold environment in which the species lives. Discussion . Recognised by the white colour, bifurcate maxillary palp, more than 5 lateral setae on the ventral tube, more than 10 dorsal setae on dens, rarely more than 4 basomedian setae on labium, and subcoxa 1 having only one seta. Otherwise it is similar to rosea which has a slightly larger PAO, more compact mucro and a more open cover of setae on Abd. 5–6 which is less rounded and more clearly separated. The erect sensilla which are observed ventrally on ant. 2–3 in rosea , are not seen in cryophila . Distribution and ecology . Only known from the type locality which is a cold water stream in the Kananaskis mountains, Alberta.