Scaphisoma, Leach, 1815

Löbl, Ivan, Leschen, Richard A. B. & Warner, William B., 2021, Scaphisomatini of Arizona (Coleoptera, Staphylinidae, Scaphidiinae) collected by V-Flight Intercept Traps, Revue suisse de Zoologie 128 (1), pp. 173-185 : 180

Key to the Arizona species of Scaphisoma

1 Body length 1.0-1.20 mm. Submetacoxal area large, extending to or nearly to mid-length of ventrite I, not margined by punctures............................................................................................................................... S. pusillum LeConte

- Body length 1.50 to 2.80 mm. Submetacoxal area small, much shorter than mid-length of ventrite I, margined by punctures..................................................................................................................................................................2

2 Mesepimeron completely or to partly fused with mesanepisternum. Antennomeres IV and V similar. Metaventrite and abdomen very finely punctate ............................................................................................ S. rufulum LeConte

- Mesepimeron distinct. Antennomere V much larger than antennomere IV. Metaventrite and/or abdomen entirely or in part distinctly punctate ....................................................................................................................................... 3

3 Metaventrite posterior submesocoxal lines and on centre much more coarsely punctate than on lateral area. Internal sac of aedeagus with robust rod ...................................................................................................... S. convexum Say

- Metaventrite with punctation similar on centre, posterior submesocoxal lines and on lateral areas. Internal sac of aedeagus without rod...............................................................................................................................................4

4 Internal sac of aedeagus with long, thin flagellum extruded in repos ........................................ [ S. commune Löbl ]

- Internal sac of aedeagus lacking flagellum..............................................................................................................5

5 Body dark reddish-brown to blackish. Antennomere VI longer than antennomeres IV and V combined. Aedeagus with basal capsule shorter than parameres ............................................................................... S. desertorum Casey

- Body light reddish-brown. Antennomere VI shorter than antennomeres IV and V combined. Aedeagus with basal capsule longer than parameres ................................................................................................... S. declivum sp. nov.