Platycerus cribripennis Van Dyke, 1928: 107

Paulsen, M. J. & Caterino, Michael, 2009, The Platycerus (Coleoptera, Lucanidae) of California, with the recognition of Platycerus cribripennis Van Dyke as a valid species, ZooKeys 8 (8), pp. 89-94 : 91-93

Platycerus cribripennis Van Dyke, 1928: 107 ; New Status.

Original combination: Platycerus depressus cribripennis Van Dyke, 1928: 107 .

Holotype male (CASC), labeled: a) “Tassajara. Cal. / Monterey Co. / V- 25 1920 / L. S. Slevin”; b) “on alder / log, chop’d / it up but / none in.”; c) blue paper, “L.S. Slevin / Collection”; d) bordered white label with red highlighted “ Holotype ” at left margin and “[male symbol] / Platycerus / depressus / cribripennis / Van Dyke”; e) “ California Academy / of Sciences / Type / No. ”/ [handprinted] “2533”; f) “ Platycerus cribripennis / Van Dyke, 1928 / det. MJ Paulsen 2008 .

Description, male (n=7). Length: 12.7-14.7 mm. Width at humerus: 4.1-4.6 mm. Color: Black ( Fig. 3 ). Head: Surface strongly alutaceous (microgranulate), irregularly punctate; puncture size variable from moderate to coarse; coarse punctures near eyes larger and more dense than in P. oregonensis or P. marginalis . Male majors with mandibles longer than head, upcurved, not evenly rounded externally; strong lateral tooth present on exterior near base; apex acute dorsally and ventrally blade-like with reduced dentition (multidentate in P. marginalis ) and with dorsal subapical tooth small, obtuse. Male minors not seen. Antennal club with 4 tomentose antennomeres, basal antennomere of club (7 th antennomere) nearly as long as antennomeres 8-10. Antennomere 6 also slightly produced internally. Pronotum: Surface strongly alutaceous, punctate; punctures irregularly spaced, moderate in size. Elytra: Surface alutaceous but more strongly shining than pronotum, densely punctate; punctures irregular (striae obscured, only sutural stria weakly evident); surface around punctures appearing raised,

subrugose. Male Genitalia: ( Fig. 2 ). Basal part of median lobe rounded, distal portion produced into two lobes. Male internal sac permanently partially everted, unsclerotized; flagellum present, sclerotized (not membranous).

Description, female (n=1). Length: 13.6 mm. Width at humerus: 4.8 mm. Differs from male as follows: Head: Surface with punctation dense, punctures larger. Mandibles shorter than head, not upcurved, lacking external tooth, instead tridentate with acute apex, dorsal, and ventral teeth. Antennal club with 4 antennomeres, basal antennomere glabrous and much shorter than remaining antennomeres. Female Genitalia: not examined.

Diagnosis. This species is distinguished from other Nearctic Platycerus by the following combination of characters: Th e black coloration and strongly alutaceous and/ or opaque dorsal surface is distinctive; the densely punctate elytra with obsolete discal striae and subrugose surface between punctures will immediately distinguish this species. The oblique, external tooth at the base of the male mandibles is unique among Nearctic Platycerus . Additionally, the male mandibles have a blade-like apex, whereas the apex is multidentate in P. marginalis , P. depressus , and P. virescens (Fabricius) and simply dentate in P. oregonensis . Th e antennal club of male P. cribripennis has the basal club antennomere not reduced and nearly as long as the three distal antennomeres; in males of P. oregonensis and P. virescens the basal club antennomere is reduced.

Distribution ( Fig. 1 ). Platycerus cribripennis is known only from California’s coastal mountains. Benesh’s assertion that other specimens were present from Yosemite and Oregon is certainly an error based on his failure to examine Van Dyke’s type.

Specimens examined (8). CALIFORNIA: KERN (1): Bear Trap Canyon, Tejon Ranch (DCCC). MONTEREY (3): Jolon (FMNH); Tassajara Road, 1 mi S of China Camp (CASC, EMEC). SAN LUIS OBISPO (1): Morro Bay (EMEC). SANTA BAR- BARA (3): Cold Spring Canyon, Los Padres National Forest (SBMN, California Beetle Project database numbers CBP0048052, CBP0049001, and CBP0049002).

Remarks. Platycerus cribripennis is one of the most infrequently collected species of stag beetles in North America, being known from only a few specimens from five localities. Th ere may be a need to examine the species’ geographically limited distribution in greater detail to ascertain whether or not it warrants conservation status. Th is is especially true where the known distribution intersects planned or on-going development.

Figures

Figure 1. Known distribution of Platycerus cribripennis in California.

Figure 2. Male genitalia of P. cribripennis, with sclerotized flagellum on the everted internal sac.

Figure 3. Dorsal habitus, P. cribripennis male.