Phlaeopterus filicornis Casey, 1886

Mullen, Logan J., Campbell, J. M. & Sikes, Derek S., 2018, Taxonomic Revision of the Rove Beetle Genus Phlaeopterus Motschulsky, 1853 (Coleoptera: Staphylinidae: Omaliinae: Anthophagini), The Coleopterists Bulletin 72, pp. 1-54 : 25-31

6. Phlaeopterus filicornis Casey, 1886

( Figs. 2B , 8B, 17C , 25C , 29G , 31H )

Phlaeopterus filicornis Casey 1886: 234 [original description]. Elias 1985: 38.

Tilea rufitarsis Casey 1893: 403 [original description]. New synonymy.

Phlaeopterus rufitarsis Casey, 1893 . Bousquet et al. 2013: 89.

Type Locality. Placer County, California, USA .

Redescription. Habitus: Length 5.9–7.7 mm. Dark brown, almost black, palpi, elytra, and glabrous apices of tibiae lighter ( Fig. 2B ). Head: Moderately narrow, ratio of width across eyes subequal to head length. Interantennal groove deeply impressed. Anteocellar foveae large, deeply impressed. Eyes glabrous or with less than 10 scattered setae near ventral margin. Antennomeres 5–10 at least 2 times longer than wide; antennomeres 4–11 each with many sensory pits with papilliform projections. Ocelli present. Nuchal constriction vague. Mandibular molar area with L-shaped row of setae. Labrum with sensory pores along entire surface ( Fig. 31H ). Labial palpi with 3 rd palpomere 1.6–1.8 times longer than palpomere 2. Thorax: Pronotum moderately narrow ( Fig. 17C ), length to width ratio = 0.76–0.81; ratio of pronotal width to head width = 1.35–1.43; maximum width less than width of elytra at bases; punctures on dorsal surface separated by average distance equal to greater than diameter of a puncture; with vague impression near midline on ventral surface; lateral margins deflexed posterad and anterad lateral foveae; lateral foveae moderately impressed. Elytra with humeral angles convex; epipleural carina not projecting; 2.4–3.2 times longer than pronotum; apical margins sexually dimorphic, elongated at suture and slightly diverging in females ( Fig. 29G ) and broadly convex and not diverging in males. Wings fully developed in most individuals, brachypterous in very few. Mesosternum with projecting tooth; longitudinal carina along midline of mesosternum complete. Legs: All tibiae glabrous, length of subglabrous apex of metatibia as ratio to metatibial length = 4.9–8.8. Metatrochanter without tooth on apical margin. Abdomen: Wing-folding spicules on tergites IV and V broad, transverse, nearly contiguous; tergite VI lacking wing-folding patches. Aedeagus: Length 1.25–1.38 mm. Median lobe somewhat triangular, apex acutely triangular ( Fig. 25C ). Parameres diverging from

Fig. 21.

lagrandeuri , B Phlaeopterus species , aedeagi (left = ventral view; right = dorsal view of median) P. houkae , C) P. longipennis , D) P. obsoletus , E) P. kavanaughi , F) P. castaneus lobe). A) P. cascadiensis .

base until just before apex. Internal sac elongate, lightly sclerotized, evenly covered in small microspinules.

Type Specimens. Phlaeopterus filicornis . Lectotype male (here designated to clarify the application of this name to this taxon, UAMObs:Ento: 235784) labeled as follows: Sept./Placer Co. Cal./ ³/CASEY bequest 1925/TYPE USNM 48108/ filicornis Casey / LECTOTYPE ³ Tilea filicornis Csy. des. 1982, J.M. Campbell. Paralectotype male (UAMObs:Ento:235785) labeled as follows: Sept./ Placer Co. Cal./ CASEY bequest 1925/CASEY det. 2 filicornis/ PARALECTOTYPE ³ Tilea filicornis Csy. , des. 1982, J.M. Campbell. The Casey Collection in the USNM contains these two males of the species.

Tilea rufitarsis . Lectotype male (here designated to clarify the application of this name to this taxon) labeled as follows: Siskiyou Co. Cal./ ³/CASEY

bequest 1925/TYPE USNM 48107/rufitarsis/ LECTOTYPE ³ Tilea rufitarsis Csy. des. 1982, J.M. Campbell. Paralectotype female labeled as follows: Siskiyou Co. Cal./ ♀ /CASEY bequest 1925/rufitarsis 2 PARATYPE USNM 48107/ PARALECTOTYPE ♀ Tilea rufitarsis Csy. des. 1982, J.M. Campbell. Paralectotype female labeled as follows: Siskiyou Co. Cal./ ♀ /CASEY bequest 1925/rufitarsis 2/ PARATYPE USNM 48107/ PARALECTOTYPE ♀ Tilea rufitarsis Csy. des. 1982, J.M. Campbell. The Casey Collection contains these three specimens.

Distribution. Phlaeopterus filicornis is known only from California in the Sierra Nevada and Cascade Range ( Fig. 8B).

Bionomics. Adults have been collected at 1,820 –3,440 m elevation from July–September under rocks near cold, fast-flowing streams or at the edges of permanent or long-lasting snowfields, and in moss at the edges of streams or in the splash zones of waterfalls.

Remarks. Phlaeopterus filicornis can be distinguished from all other Phlaeopterus species by the shape of the pronotum (length:width ratio, lateral margins, and lateral foveae), sexually dimorphic shape of the elytral apices, glabrous apices of the tibiae, and form of the aedeagus. It is highly similar to P. hatchi , from which it differs by the sexually dimorphic shape of the elytral apices, pronotum with a vague impression near the midline on the ventral surface, shape and size of the median lobe of the aedeagus, microspinules of the internal sac of the aedeagus, and a slight difference in body length.

We examined the lectotypes of P. filicornis and P. rufitarsis and were not able to find any significant differences between the two specimens. Therefore, we chose to synonymize P. rufitarsis under P. filicornis .

Figures

Fig. 2. Phlaeopterus species, habitus. A) P. elongatus, male (UAMObs:Ento:232543), B) P. filicornis, female

Fig. 17. Phlaeopterus species. Pronota, dorsal view, of A) P. fusconiger, B) P. frosti, C) P. filicornis, D) P. hatchi, E) P. elongatus. Abdominal segments 4–6, dorsal view, of F) P. houkae, G) P. obsoletus, H) P. elongatus.

Fig. 25. Phlaeopterus species, aedeagi (left = ventral view; right = dorsal view of median lobe). A) Phlaeopterus frosti, B) P. hatchi, C) P. filicornis, D) P. elongatus.

Fig. 29. Phlaeopterus species. Right mandibles, ventral view, of A) P. obsoletus, B) P. bakerensis, C) P. elongatus. D) P. bakerensis, humeral angle of elytron, dorsal view. Apices of elytra of E) P. loganensis, F) P. hatchi, G) P. filicornis female.

Fig. 31. Labra of A) Lesteva pallipes, B) Lesteva pubescens, C) Unamis sp. undescribed, D) Unamis sp., E) Phlaeopterus lagrandeuri, F) Phlaeopterus houkae, G) Phlaeopterus obsoletus, H) Phlaeopterus filicornis. White arrows indicate labrum.