Idahotyphlus alleni Gusarov, sp. n.

Idahotyphlus alleni Gusarov, sp. n. (Figs. 1–22)

Type material. Holotype: ɗ, UNITED STATES: Idaho: Boise Co.: Beaver Creek Summit, funneled from Ponderosa pine litter (A.D.Allen), 3.vii.1978 (KSEM).

Paratypes: UNITED STATES: Idaho: Boise Co.: 3ɗɗ, 13ΨΨ, same data as the holotype (AACB, KSEM, SPSU, WFBM); 3ΨΨ, ca. 30 mi. NE Boise, Ten Mile Camp Area, funneled from Ponderosa pine litter (A.D.Allen), 29.v.1978 (AACB, SPSU); ɗ, 2ΨΨ, ditto but 20.v.1982 (FMNH, SPSU); Valley Co.: 3ΨΨ, Warm Lake, pine litter (A.D.Allen), 4.vi.1982 (FMNH).

Diagnosis. Idahotyphlus alleni is the only known species of the genus Idahotyphlus. If any additional species of Idahotyphlus are ever discovered, I. alleni could probably be distinguished by the shape of the aedeagus (Figs. 15–20) and the shape of the female accessory sclerites (Fig. 22).

Description. Length 1.4–1.7 mm.

Head with short setae arranged as in Figs. 1–2. Second antennal article slightly longer than wide, twice as long and 1.4 times as wide as article 3, articles 3–9 transverse, 1.2–1.5 times as wide as long, article 10 is 1.3 times as wide as long, last article elongate, 1.3 times as long as wide.

Pronotum with short setae arranged as in Fig. 1, narrowed posteriad, 1.1 times as wide as long, as wide as head and elytra. Elytra with short setae, with lateral sides diverging posteriad (Fig. 1), 1.1 times as wide as long (length measured from humeral level).

Male mesotrochanter without modification (Fig. 13). In males, setae on ventral side of protarsus thicker than in females (cf. Figs. 11 and 12), but in both sexes the setae lack apical adhesive disks. Male abdominal sternum 8 with broad and shallow apical emargination, without zone devoid of setae (Fig. 21).

Aedeagus long and narrow, without denticle on parameral surface (Figs. 15–20). Internal sac with long needle­shaped sclerite which is as long as median lobe; when retracted the sclerite exposed apically.

Female accessory sclerites as in Fig. 22, poorly sclerotized.

Distribution. Known from three localities in Idaho (Fig. 23). The males from both localities in Boise County are identical in the shape of the aedeagus and its internal sclerite. No males are known from the locality in Valley County but the females are identical to those from the type locality in all external characters, including the shape of the terminal abdominal segments, and in the shape of the female accessory sclerites.

Natural History. Idahotyphlus alleni was found in funnel extract of forest litter taken at the base of a big Ponderosa pine tree (Pinus ponderosa) (Allen, personal communication).