PSELAPHINAE OF HJA

Chandler, Donald S., Parsons, Gary L. & Moldenke, Andrew R., 2020, The Ant-Like Litter Beetles of the H. J. Andrews Experimental Forest, Oregon (Coleoptera: Staphylinidae: Pselaphinae), The Coleopterists Bulletin 74 (3), pp. 463-488 : 468-471

KEY TO SPECIES OF PSELAPHINAE OF HJA

Notes. Specimens are easily identified when dried and glued on points, as long as the mount adhesive is not excessively applied. Males are generally best for confirmation of identification, since they have more diagnostic features than females. However, both sexes in Sonoma may be readily identified. Males have an additional ventrite at the apex of the abdomen, which is

Figs. 1–8. Dorsal view of 8 generic representatives. 1) Sonoma hespera; 2) Mayetia smithi; 3) Oropus striatus; 4) Actium barri; 5) Batrisodes albionicus; 6) Pselaptrichus rothi; 7) Lucifotychus impellus; 8) Adranes taylori. Scale bars = 0.5 mm.

either small and oval or somewhat transverse and medially impressed. The last female ventrite is transverse and is convex, medially flattened, or only vaguely impressed at the middle, except for females of Sonoma whose apical ventrites are variously modified.Depending on the genus males may have complex structures on the underside of the head, enlarged antennomeres, modifications of the apical abdominal tergites, toothed, setose or impressed lateral areas of the abdominal ventrites, or legs with teeth or angulations of the trochanters or tibiae. Females lack all of these. The most useful paper for identification within a genus is indicated at an appropriate place in the key for those who wish to investigate the potential discovery of unrecorded species for the forest. The species are numbered and arranged in a system following the current arrangement of taxonomic groups for this subfamily.Those species with an asterisk have not yet been collected in the HJA, but are expected to occur there.

1. Body elongate and slender, with head, thorax and abdomen same width (Fig. 2); body 0.8 mm long ........................... ............... 7. Mayetia smithi Schuster

10. Body more robust, head usually narrower than prothorax, always narrower than meso/metathorax or abdomen (Figs. 1, 3–8); body longer .......................... 2

2(1). Abdomen rounded laterally, lacking carinae separating tergites from ventrites for segments except shortly present at the basolateral margin of first visible abdominal segment (Fig. 5); Batrisodes [revision: Grigarick and Schuster 1962a] ................... 3

20. Abdomen angulate laterally, with lateral carinae separating tergites, paratergites, and ventrites from each other on segments 1–4 (Figs. 1, 3–4, 6–8) .......... 4

3(2). Head with lateral vertexal carinae extending posteriorly from antennal tubercles to above eyes; both sexes with last tergite strongly projecting in lateral view (Figs. 10A–B) .......................... ......... *Batrisodes denticauda (Casey)

30. Head lacking lateral vertexal carinae; male with last tergite broadly rounded, only female with last tergite bluntly protruding (Figs. 9A–B) .................... ....... 21. Batrisodes albionicus (Aubé)

4(2). Maxillary palp with third (penultimate) segment elongate, more than half as long as last segment, inner margin protruding, fourth (apical) segment with narrow apical lobe (Figs. 7, 11); Lucifotychus [key: Grigarick and Schuster 1962b] .......... 5

40. Maxillary palp with third segment onethird or less length of last segment, mesal margin straight to evenly curved, fourth segment lacking apical lobe (Figs. 4, 6) ............................................... 8

5(4). Elytra same color as prothorax and abdomen; male with strongly projecting metaventral tubercle just posterior to mesocoxae ............... ........................ 25. Lucifotychus impellus Park and Wagner

50. With elytra markedly lighter than prothorax and abdomen; male lacking metaventral tubercle ............................ 6

6(5). Male genitalia with parameres short, less than half as long as median lobe (Fig. 14) ............ 26. Lucifotychus stellatus (Grigarick and Schuster)

60. Male genitalia with parameres longer, almost reaching apex of median lobe (Figs. 12–13) ................................ 7

7(6). Male genitalia with ventral portion of median lobe laterally tuberculate near apex (Fig. 13) ................ 24. Lucifotychus dentatus (Grigarick and Schuster)

70. Male genitalia with ventral portion of median lobe lacking lateral tubercles (Fig. 12) .............. 23. Lucifotychus cognatus (LeConte)

8(4). Last segment of maxillary palp enlarged, at least half as long as head, antennomere 1 elongate, as long as antennomeres 2–7 (Fig. 6); male with underside of head modified as prominent gular tubercle; Pselaptrichus [revision: Schuster and Marsh 1956] ................................... 9

80. Last segment of maxillary palp not enlarged, at most one-third of head length (Figs. 2–4); antennomere 1 not as elongate, as long as antennomeres 2–4; male lacking modifications of head underside ............................................. 13

9(8). Large, 2 mm or more in length; male gular tubercle widely emarginate at middle (Fig. 20) .............................. ............. 28. Pselaptrichus rothi Park

90. Smaller, 1.7 mm or less in length ........... 10

10(9). Gular tubercle not raised medially (Fig. 21) .................. *Pselaptrichus vanus Schuster and Marsh

100. Gular tubercle raised at middle (Figs. 17–19) ....................................... 11

11(10). Gular tubercle weakly bidentate at middle on anterior margin (Fig. 18) .......... .................... *Pselaptrichus perditus

Schuster and Marsh 110. Gular tubercle emarginate on anterior

margin ....................................... 12

12(11). Gular tubercle with lateral flanges prominent, broadly truncate (Fig. 19) ... .................... *Pselaptrichus perfidus

Schuster and Marsh

120. Gular tubercle with lateral flanges short, broadly rounded (Fig. 17) .................. ................. 27. Pselaptrichus intimus

Schuster and Marsh

13(8). Antenna with 3 antennomeres, antennomere 3 much longer than first two combined (Fig. 8); eyes absent [key: Wickham 1901] ............................... ............... *Adranes taylori Wickham

130. Antenna with 11 antennomeres, last antennomere at most as long as previous segments combined (Figs. 1, 3–4); eyes present ....................................... 14

14(13). Tarsi with first two tarsomeres short, last tarsomere long (Fig. 15); elytron with foveae at base and also on disc (Fig. 1); Sonoma [revision: Ferro 2016] ......................... 15

140. Tarsi with second tarsomere as long or longer than third (Fig. 16); elytron with 2–4 foveae only at base (Figs. 3–4) ...................... 20

15(14). Head with frontal fovea circular to rounded-triangular, at most only slightly longer than width near base (Fig. 24) .... .................................................. 16

150. Head with frontal fovea elongate, expanded at apex, twice as long as width near base (Fig. 2) ......................... 17

16(15). Frontal fovea elongate; pronotum with discal foveae distinct; male genitalia with bifurcate median lobe (Fig. 27A); female abdominal ventrite 6 projecting at apex as rectangular lobe (Fig. 27B) ................ .......... 1. Sonoma cascadia Chandler

160. Frontal fovea small, circular; pronotum with discal foveae weak; male genitalia with apex of median lobe truncate (Fig. 28A); female abdominal ventrite 6 asymmetrically bidentate at middle, extending to touch ventrite 7 (Fig. 28B) .................... .............. 2. Sonoma conifera Chandler

17(15). Antennomere 4 slender, almost half again as long as wide; male genitalia with median lobe curved laterally (Fig. 32A); female genitalia with ventrite 6 notched on left side (Fig. 32B) ...................... .......... 6. Sonoma parviceps (Mäklin)

170. Antennomere 4 globose, about as long as wide .......................................... 18