Platyceroides (Platyceroides) barrae Paulsen

Paulsen, M. J., 2017, Correction of existing generic and species concepts in Platyceroidini (Coleoptera: Lucanidae: Lucaninae) and the description of four new species of Platyceroides Benesh, Zootaxa 4269 (3), pp. 346-378 : 364-366

Platyceroides (Platyceroides) barrae Paulsen , new species

Type series. Holotype male and allotype female deposited at EMEC, labeled: a) “CA: Nevada County / Tahoe Natl. Forest / Eagle Lakes Trail / 12-VI-2016, C.B. Barr / coll. on the ground”; b) on red paper, “ Platyceroides / barrae Paulsen / HOLOTYPE (or ALLOTYPE)”. One female paratype ( MJPC) labeled a) as holotype . One male paratype ( CASC) labeled, all handwritten, a) “ Cisco / Cal. / VII-1911 ”; b) “Coll. by C. / Van Golden ”; c) “ Van Dyke / Collection”. One male paratype ( AMNH) labeled, all handwritten, a) “ VII-4-52 / Blue Lk. / Nev Co Cal. ”; b) “14047? / C.A.F. ‘61”; c) male symbol; d) “14047 / B.B. ‘64”. Nine male paratypes ( AMNH, FMNH, MJPC) labeled, all handwritten, a) “VII-2.52 / C.B. P, Nev. / Co. Calif. ”; b) “14047? / C.A.F. ‘61”; c) male symbol; d) “14047 / B.B. ‘64”; one with label “ Platyceroides / agassizi / B.B. -64 14047 (LeC)”. All paratypes with label: on yellow paper, “ Platyceroides / barrae Paulsen / PARATYPE ” .

Description, holotype male ( Fig. 12 A). Length: 10.4 mm. Width: 4.5 mm. Color: Dark piceous, with moderate bronze reflection. Head: Form narrow anteriorly, with gena not produced laterally as far as eye. Antennal club large (subequal to length of scape), size of distal antennomere of club larger than dorsal surface of eye, antennomeres of club entirely tomentose. Clypeus not thickened apically. Labrum relatively small, shorter than width of distal maxillary palp. Mandibles falcate, robust, strongly bent internally after base, internally with 1 indistinct tooth. Pronotum: Surface shiny (minutely shagreened) with large, deep punctures; punctures dense, generally separated by about 1 puncture diameter, distance between punctures becoming greater on center of disc and in explanate lateral margins; median line and area on either side more-or-less impunctate. Form broad, lateral margins broadly rounded, posterior angle nearly 90°. Elytra: Form elongate. Surface shiny, shagreened, with some transverse rugae, weakly striate (sutural and 2–3 striae on disc); striae with row of moderately deep punctures; intervals with punctures finer, irregular. Wings: Wings fully developed. Legs: Mesotibiae and metatibiae not distinctly slender. Abdomen: Male genitalia with permanently everted internal sac sclerotized, elongate, with capitate apex; apex emarginate (ventral view) and acutely produced in lateral view ( Fig. 12 C).

Description, allotype female ( Fig. 12 B). Length: 10.5 mm. Width: 4.7 mm. Differs from male holotype in the following characters. Color: Lighter reddish brown. Head: Antennal club smaller, shorter than length of scape, antennomeres of club mostly glabrous. Mandibles blade like, externally rounded. Labrum longer. Pronotum: Form broader. Surface less punctate medially. Posterior angles more strongly produced, <90°. Elytra: Form robust, less elongate, suboval. Surface with striae not distinctly impressed; intervals with finer punctures. Wings: Wings atrophied. Legs: All tibiae distinctly broader, more robust than in male.

Variation in paratypes. Males (n = 11): Length: 9.1–10.4 mm. Width: 3.8–4.5 mm. Color: Lighter reddish to brown piceous. Pronotum: Surface punctation variably dense, more densely punctate either side of median line. Posterior angle variable, 90° to acute. Female (n = 1): Length: 10.4 mm. Width: 4.7 mm.

Etymology. The species is named for Cheryl B. Barr (EMEC), a specialist on aquatic beetles, who recently collected the primary types and the only known female specimens. I am pleased to name this species for her in acknowledgment of her generous assistance with my research and for her skill at also finding the good terrestrial beetles.

Diagnosis. The apex of the male genitalia is diagnostic for this species due to the presence of an acute apical process. Both sexes can be immediately separated from the two geographically closest species by the thickened clypeal apex in P. latus and the much smaller antennal club in P. potax .

Distribution ( Fig. 28 ). CALIFORNIA: NEVADA: Blue Lake; “C.B.P.”; Eagle Lakes. PLACER: Cisco. Temporal distribution. June (3), July (11). Adults have been collected somewhat later than with other species, which may be related to the high elevation of 1700–1800 m.

Remarks. The largest series comes from a Nevada County, California, locality listed simply as “C.B.P.” My attempts to decipher that locality, including queries to several inveterate California collectors, have been unsuccessful. The five remaining specimens with clear locality data are from a relatively small area, and I assume that “C.B.P.” would be near to them as well. The life history of the species is unknown, with recent specimens being found walking on trails in a closed-canopy coniferous forest (Cheryl Barr, personal communication). The limited distribution of this species may be a cause for conservation concern.

Figures

FIGURE 12. Platyceroides opacus species group. 12 A – C, Platyceroides barrae new species; 12 A, holotype male; 12 B, allotype female; 12 C, flagellum of male genitalia, arrow indicates acute apical process. 12 D – F, flagellum of male genitalia for comparison: 12 D, P. opacus; 12 E, P. potax; 12 F, P. marshalli.

FIGURES 27 – 28. Distribution of Platyceroides species. 27, Platyceroides californicus species group: P. aeneus (orange triangles); P. umpquus (blue circles); P. californicus (orange squares); P. thoracicus (blue triangles). 28, Platyceroides opacus species group: P. marshalli (blue squares); P. potax (orange squares); P. barrae (blue circles); P. opacus (orange circles).