la rue2007 pleocoma hovorei

A NEW SPECIES OF PLEOCOMA LECONTE FROM CALIFORNIA (COLEOPTERA:

SCARABAEOIDEA: PLEOCOMIDAE)

DELBERT A. LA RUE

Research Associate, Entomology Research MuseumUniversity of California

Riverside, CA 92521, U.S.A.

Abstract

Pleocoma hovorei La Rue, new species, is described and illustrated from Shasta andTehama Counties, California, U.S.A. Included are remarks on taxonomy, adult behavior,and ecology. Based upon congruent morphological characters the new taxon is associatedwith the P. staff species group.

Heretofore, the P. staff species group of the genus Pleocoma LeConte wasconsidered monotypic, being comprised solely of the nominate species distributedin the northern Sierra Nevada Mountains: Butte, Nevada, and Yuba Counties,California (Fig. 5). Recent collections and field surveys, guided in part by priorliterature (Linsley 1945:113–114; Hovore 1977:231, 1981:2) have revealed anundescribed species from Shasta and Tehama Counties, California, whose salientmorphological characters are synapotypically congruent with the P. staff speciesgroup.

Specimens examined are deposited in the private collections of the respectivecollectors except where indicated by the following codens: CRSC - C.R. Smith,Anderson, CA; DALC - D.A. La Rue, Willcox, AZ; FTHC - F.T. Hovore, to bedeposited at the California Academy of Sciences, San Francisco, CA; LRBC -L.R. Bronson, Summit City, CA.

Pleocoma hovorei La Rue, new species(Figs. 1–2)

Type data. Holotype male (Deposited at the California Academy of Sciences#17942). ‘‘U.S.A., California, Shasta County, Black Butte Rd., 27-29.XI.1999,L.R. Bronson, D.A. La Rue, C.R. Smith, 8w BLT, Pinus-Arctostaphylos.’’Allotype female (also deposited at the California Academy of Sciences), samedata as holotype except ‘‘on soil surface.’’

Paratypes (244). Same data as holotype (25 males, 1 female, DALC); samelocality as holotype except labeled as ‘‘Black Butte Rd. and Alpine Way,’’20.XII.1995, R. Meadville (1 male, LRBC); 06.XII.1996, R. Meadville (13 males,LRBC 12, DALC 1); 26.XII.1997, C.R. Smith (4 males, DALC 1); 04.XII.1998,R. Meadville (2 males, CRSC); Palo Cedro, 30.X.1986, D.C. Rogers (2 males,FTHC); 06.XII.1997, D.C. Rogers (1 male, FTHC); Old Rt. 44, 18-20.XI.1998,M. Cassells, F.T. Hovore (19 males, FTHC); 09-10.XI.2002, F.T. Hovore, R.L.Penrose (4 males, FTHC); 15-17.XII.2002, F.T. Hovore, R.L. Penrose (34 males,6 females, FTHC); 10-13.XII.2002, F.T. Hovore, R.L. Penrose (10 males,FTHC); 02-03.XII.2003, F.T. Hovore, R.L. Penrose (2 males, 2 females, FTHC);W. of Old 44 Bridge, North Cow Creek, 09.II.1988, D.C. Rogers, M. Cassells(2 males, FTHC); 04.II.1996, D.C. Rogers (6 males, FTHC); 09.XI.1998, D.C.

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Rogers (1 male, FTHC); Route 44 & Dersch Rd., 01.XII.2003, F.T. Hovore, R.L.Penrose (1 male, FTHC); Redding, Mountain Gate at Old Oregon Trail & I-5,29.IX.1988, D.C. Rogers (1 male, FTHC); Keswick Dam Rd. & A-18,22.XII.1991, D.C. Rogers (1 male, FTHC); Lake Blvd. & Walker Mine Rd.,24.II.1991, D.C. Rogers (2 males, FTHC); Williamson Rd. & Walker Mine Rd.,29.XI.1999, D.A. La Rue (2 males); Larkspur Lane & E. Cypress Ave.,15.XII.2003, M.K. Fowler (1 male, DALC); Shasta City, 09.XI.-13.XII.2002,L.R. Bronson (7 males); 16.XII.2002, F.T Hovore, R.L. Penrose (1 male, FTHC);09.XI.-15.XI.2003, L.R. Bronson (15 males); Summit City, 11.XII.-12.XII.1994,L.R. Bronson (9 males); 6.XII.-15.XII.1995, L.R. Bronson (12 males, CRSC 1);19.XI-10.XII.1996, L.R. Bronson (8 males, DALC 5); 27-29.XI.1999, D.A. LaRue (3 males).

California, Tehama County, Lyman Springs, near Lyonsville, 12.X.2000, D.A.La Rue (3 males); 08-11.XI.2002, J. Dalton (6 males, FTHC); 24.XI.2002, I.P.Swift (1 female, FTHC); 07.XI.2003, F.T. Hovore, I.P. Swift (5 males, FTHC);Jct. Plum Creek Rd. & Ponderosa Rd., 12.X.2000, D.A. La Rue (3 males); LittleGiant Mill Rd., 1 mi. NW of Lyonsville, 31.X.2001, C.R. Smith (1 male); 0.5 mi.S. Jct. Plum Creek Rd. & Ponderosa Rd., 09.XI.2004, I.P. Swift (1 male, FTHC);


Figs. 1–4. Dorsal habitus photos of Pleocoma hovorei, new species, and P. staff. 1)holotype male, P. hovorei; 2) allotype female, P. hovorei; 3) male, P. staff; 4) female, P. staff.

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2 mi. S. Jct. Plum Creek Rd. & Hogsback Rd., 09.XI.2004, I.P. Swift (1 male,FTHC); Ponderosa Sky Ranch, 12.X.2000, D.A. La Rue (14 males); 31.X.2001,C.R. Smith (2 males); 16.XI.2001, C.R. Smith (9 males).

Paratypes are deposited at the California Academy of Sciences (San Francisco,CA), the Entomology Research Museum, University of California, Riverside;Smithsonian Institution, National Museum of Natural History (Washington,DC); and the private collections of L.R. Bronson (Summit City, CA); R.A.Cunningham (Chino, CA); F.T. Hovore (to be deposited at the CaliforniaAcademy of Sciences, San Francisco, CA); H.F. Howden (deposited at theCanadian Museum of Nature, Ottawa, Ontario, Canada); R.E. Jensen (CanogaPark, CA); S. McCleve (Douglas, AZ); R.H. McPeak (Battle Ground, WA); C.R.Smith (Anderson, CA); B.D. Streit (Tucson, AZ); G.C. Walters (La Puente, CA);W.B. Warner (Chandler, AZ); and the author.

Description. Holotype. Male (Fig. 1). Length. 27.5 mm. Greatest width.17.5 mm. (15.0 mm. at elytral humeri). Form. Stout, robust, oval, moderatelyconvex dorsally. Color. Dorsal integument uniformly shining concolorous black;posteromedial pronotal disk indistinctly clouded with cupreous red to reddish-brown when viewed under magnification (.253); head with frons, vertex,anteocular margin, eyes, reflexed anterior surface of vertical horn, black; tibiadark reddish-brown to black; dorsal surface of ocular canthi, medial scutellardisk, antennae and other appendages of head, remainder of legs and venter,reddish-brown; lamellae of antennal club light brown with a golden pruinosesheen; pubescence bright golden reddish-brown. Head. Convex, narrow, entirely,densely, coarsely to rugosely punctate, obscuring frontoclypeal suture, with long,


Fig. 5. Distribution map (modified from Hovore 1977:238). P. hovorei, new species,circles; P. staff, squares.

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golden reddish-brown setae. Eyes large, prominent, partially divided by canthus;dorsal surface of ocular canthi glabrous and shining, obtusely rounded distally,anterior edge produced obliquely, weakly reflexed at confluence with verticalhorn, posterior edge coarsely punctate, eroded, each puncture with a long goldenreddish-brown seta. Clypeal horn erect, bifurcated, deeply emarginate, broadlyrounded at basal coalescence, apex divergent, weakly reflexed posteriorly, frontalsurface glabrous, irregularly, coarsely punctate, heavily provided with goldenreddish-brown setae at basal constriction. Vertex with subtriangular to conical,coarse to rugosely punctate, protuberance (head horn). Antennae with 11antennomeres; scape elongate, tapering posteriorly, provided with scattered,erect, golden reddish-brown bristle-like setae; antennomere 2 transverse;antennomere 3 long, arcuate, strongly, obtusely, angulate anteriorly at apex,subequal in length to that of scape and antennomere 2 combined, with fewscattered golden reddish-brown bristle-like setae. Antennomere 4 angulateanteriorly with lamellate projection approximately 1/2 length of antennomere 5,irregularly setose, provided with long bristle-like setae; antennomeres 5 through11 elongate, subequal in length, forming lamellate club, distal tip of each lamellaweakly curved outward, irregularly provided with short golden spiculae; receptorspresent on entire surface of each lamella (603). Mentum transverse, coarselypunctate; mouthparts fused, reduced; mandibles non-functional; maxillary palpi4-segmented, each palpomere long, cylindrical, subequal in length, variablysetose, provided with golden reddish-brown bristle-like setae; labial palpi 4-segmented, palpomere 1 bulbous, transverse, palpomeres 2–4 long, cylindrical,subequal in length, variably setose, provided with long golden reddish-brownbristle-like setae. Pronotum. Broad, strongly convex, transverse, approximately2.53 wider than length at midline, widest at anterolateral angles. Basal anglesbroadly obtuse and explanate; marginal bead complete, slightly raised andreflexed. Disk glabrous, finely to moderately, irregularly punctate except fornarrow, smooth, longitudinal band at midline. Margins heavily fimbriate withgolden reddish-brown pubescence of variable length, especially evident andrecumbent at occipital and elytral articulation; tumid, transverse prominencemedially, anteromedial impression lacking, posteromedial impression immediate-ly behind transverse prominence deeply depressed, spatulate in shape; surface ofpropleura finely punctate, densely clothed with a mixture of short, fine goldenand long reddish-brown setae; very finely punctate with fine short pale setaeanteriorly. Scutellum. Transverse, subtriangular, weakly concave, punctate aspronotum, medially with a small, shining, translucent impunctate area, posteriormargin broadly rounded, medially provided with short, recumbent, goldenreddish-brown setae. Elytra. Elongate, lateral margins arcuate; longitudinally2.53 greater than wide, weakly explanate at posterior 2/3. Marginal beadcomplete, heavily fimbriate with long, erect reddish-brown setae; humeral anglessharply rounded anteriorly; posterior angles broadly, obtusely rounded. Distinctlinear pattern of discal striae and costae that are well defined and deeplyimpressed by coarse, contiguous punctation and fine to moderate, scatteredpunctures; both extending longitudinal distance of elytra. Intervals weaklyconvex, deeply, rugose with coarse contiguous punctures; sutural costae raised,smooth, glabrous, very finely, sparsely punctate; humeral calla noticeably tumid,glabrous, anteriorly abruptly obvolvent. Metathoracic wings. Completely de-veloped, infuscated; radial posterior and median posterior+2 veins sinuate,reduced to a narrow loop; Anal anterior vein long and arcuate. Pygidium.Transverse, subtriangular; margin obtusely rounded at distal apex, weakly sinuate



at posterolateral 1/2, bead coarsely eroded with rugose punctures, heavilyprovided with reddish-brown setae of variable lengths. Disk translucent, veryfinely, evenly punctate, vestiture composed of very fine, short, recumbent palesetae (403), and irregularly scattered, long, reddish-brown setae. Venter. Denselypubescent with long, golden reddish-brown setae, obscuring ventral integument. 4abdomeres variably exposed, slightly convex, each with a fine posterior marginalbead, surface finely to rugosely punctate. Legs. Procoxae large, prominent,conical; meso-, metacoxae contiguous, prominent; anterior surfaces of pro-,meso-, and metafemora glabrous, finely punctate. Dorsal surfaces finely torugosely punctate, with elongate elliptical vestiture of fine, short, pale to reddish-brown setae. Protibiae with a short, blunt, linear apical spur, heavilyquadridentate on outer margin, proximal tooth greatly obtuse, anterior 2ndthrough 4th subequally separated; surface deeply, rugosely punctate, submarginaledge with long, coarse reddish-brown setae following contour of dentition; lengthof proximal edge with row of short, pale spiculae; meso-, metatibiae stronglyridged on outer margin; finely to coarsely, contiguously punctate, longitudinallywith a row of long reddish-brown setae; meso-, metatibiae with 2 stout, short,asymmetric linear apical spurs; all tarsomeres simple, subcylindrical, elongate;tarsomeres 1 through 4 subequal in length, tarsomere 5 subequal in length topreceding 3 combined; irregularly provided with short recumbent to long reddish-brown setae; unguifer plate extending slightly beyond articulation of tarsomere 5;tarsal claws elongate, symmetrical, strongly uncinate. Genitalia. Numberexamined. 5. Typical of genus; symmetrical, simple, internal sac reduced, feeblysetose; of no apparent intraspecific diagnostic value.

Allotype. Female (Fig. 2). Length. 33.5 mm. Greatest width. 20.5 mm.(16.5 mm. at elytral humeri). Form. Large, robust, ovoid, heavy bodied, stronglyconvex. Color. Dorsal integument uniformly shining, appearing bicolorous; head,pronotum rich reddish-brown; elytra, pronotal marginal bead, dorsal surface ofocular canthi, scutellum, antennae and other appendages of head, remainder oflegs and venter, dark reddish brown, appearing piceous to unaided eye; eyes,reflexed margin of vertical horn, margins of protibial dentition, black; tibia darkreddish-brown to black; exposed abdomeres yellowish-brown; pubescence brightgolden reddish-brown. Head. Moderately convex, wide, entirely, densely, coarselyto rugosely punctate, obscuring clypeo-frontal suture; variably with long, goldenreddish-brown setae. Ocular canthi broadly obtuse to subquadrate at apex,shining, glabrous, with an oblique shallow carina. Vertical horn short, transverse,disc weakly tumid, anterior margin strongly reflexed, medially deeply emarginate,outer edge coarsely eroded; frontal surface irregularly, coarsely punctate, heavilyprovided with short golden reddish-brown setae. Vertex with feeble, transverse,subtriangular, coarse to rugosely punctate protuberance (head horn); 2 shallow,glabrous symmetrical swellings immediately behind head horn; occipital bandglabrous, shining. Antennae with 11 antennomeres; scape elongate, with erectsetae; antennomere 3 elongate, subarcuate, tapering posteriorly; antennomere 4transverse; antennomeres 5 through 11 with stout, sinuate lamellae forming club;each lamella finely punctate, variably with short pale spiculae at apical tip.Mentum weakly transverse, moderately punctate, variably with reddish-brownsetae. Mouthparts fused, reduced; maxillary palpi 4-segmented, palpomere 2 long,cylindrical, greater in length than palpomeres 3 and 4 combined, heavily setose,apically with golden reddish-brown bristle-like setae; labial palpi 4-segmented,each palpomere cylindrical, subequal in length, variably setose with short goldenreddish-brown bristle-like setae. Pronotum. Broad, transverse, strongly convex,



approximately 2.53 wider than length at midline, widest anterolaterally; anteriorangles rounded; basal angles widely, obtusely rounded, extending over elytralhumeri; anteriorly emarginate; marginal bead incomplete, absent anteriorly,feebly crenulate mediolaterally; disk glabrous, finely to rugosely punctate, heavilyrugose laterad; explanate mediolaterally; margins entirely, heavily fimbriate withgolden reddish-brown pubescence of variable length; surface of propleura finelypunctate, densely clothed with a mixture of short, fine golden and long reddish-brown setae. Scutellum. Strongly transverse, subtriangular, feebly concave,posterior margin broadly rounded, very finely punctate, with few scattered short,recumbent, golden reddish-brown setae. Elytra. Elongate, anterolateral marginsweekly divergent, strongly arcuate posterolaterally; longitudinally approximately2.253 greater than wide. Marginal bead present at lateral 2/3, eroded tocrenulate; heavily fimbriate throughout with long, erect reddish-brown setae.Humeral angles sharply rounded; posterior angles very broadly, obtuselyrounded. Distinct linear pattern of discal striae and costae that are well definedand shallowly to moderately impressed by coarse, contiguous punctation and fineto moderate, scattered punctures; both extending longitudinal distance of elytra;intervals deeply, rugose with coarse contiguous punctures; sutural costae feeblyraised, smooth, glabrous, very finely to rugosely, sparsely punctate. Humeriglabrous, smooth, abruptly obvolvent. Metathoracic wings. Brachypterous, non-functional. Pygidium. Transverse, subtriangular; partially obscured from aboveby elytral apices; margin obtusely rounded at distal apex, bead coarsely erodedwith rugose punctures, heavily provided with reddish-brown setae of variablelengths; disk finely, evenly, rugosely punctate, provided with irregularly scattered,short golden setae. Venter. Densely pubescent with variably short to long, brightgolden reddish-brown setae; visible areas of pterothoracic integument finelycoriaceous; 4 abdomeres variably exposed, each slightly convex with a fineposterior marginal bead; surface of each finely coriaceous. Legs. Procoxae large,prominent, conical; meso-, metacoxae contiguous, prominent; anterior surfaces ofpro-, meso-, and metafemora rugosely to finely punctate; dorsal surfaces rugoselyto finely punctate, with irregular vestiture of fine, short, pale to reddish-brownsetae. Protibiae large, heavily quinquedentate on outer margin, proximal 1st and2nd tooth short, contiguous, greatly obtuse; anterior 3rd through 5th subequallyseparated; anterior surface deeply, rugosely punctate, submarginal edge withlong, coarse reddish-brown setae following contour of dentition; length ofproximal edge with row of short, pale spiculae. Mesotibiae with 2 linear, short,blunt asymmetric apical spurs, inner spur subequal in length to 23 outer spur;outer margin with a produced, thin, sinuate flange, extending obliquely outward;meso-, metatibiae finely to coarsely, contiguously punctate, longitudinally witha row of long reddish-brown setae and coarse, short yellowish spiculae. Alltarsomeres simple, globose; tarsomeres 1 through 4 subequal in length, tarsomere5 elongate, globose at apex, subequal in length to preceding 3 tarsomerescombined; variably with short recumbent to long reddish-brown setae; tarsalclaws short, symmetrical, weakly uncinate. Genitalia. Not examined.

Diagnosis. Adults may be recognized by the following combination ofmorphological characters:

Males. Size moderate (length 22.5–29.0 mm); robust oval; dorsal integumentuniformly shining concolorous black, scutellum, appendages and venter reddish-brown, pubescence bright golden reddish-brown. Ocular canthi obtusely roundedat apex. Vertical horn bifurcated and deeply emarginate, apex divergent, reflexedposteriorly, narrowing toward base. Antennomere 3 elongate, arcuate, angulate



anteriorly at apex; antennomere 4 angulate anteriorly as a lamellate projection 1/4to 2/3 length of antennomere 5; antennomeres 5 through 11 forming club,lamellae elongate and subequal in length. Pronotum glabrous, convex, broadlytransverse, approximately 2.53 wider than long at midline, widest at broadlyrounded anterolateral angles with basal angles obtuse and narrowing, disk finely,evenly punctate, medially with a prominent transverse carina; anteromedialimpression lacking, posteromedial impression moderately to deeply depressed andspatulate in shape. Elytra with discal striae distinctly incised and completethrough linear length, rugosely contiguous to finely, moderately punctate;intervals deeply rugose with coarse, contiguous punctures; costae smooth.Protibiae moderately robust; tarsomeres elongate.

Females. Size large (length 30.0–35.5 mm); broadly robust; elytral integumentuniformly shining dark reddish-brown to piceous, pronotum reddish-brown;appendages and venter chestnut brown, pubescence bright golden reddish-brown.Ocular canthi broadly obtuse at apex; vertical horn short, reflexed, transverse,deeply emarginate at apex. Antennae with antennomere 3 elongate, subarcuate;antennomere 4 transverse, angulate anteriorly; antennomere 5 through 11 withstout lamellae forming club. Pronotum broad, transverse, evenly convex, widestanterolaterally, basal angles obtuse; discal surface glabrous, coarsely punctatewith rugose areas. Scutellum glabrous, coarsely punctate. Elytra glabrous,coarsely punctate with heavy rugose areas, discal striae and costae distinct,moderately incised and complete through linear length.

Intrapopulational variation. Primary intrapopulational character variationincludes dorsal color, antennal profile of antennomeres three and four, relativelamellar configuration, pronotal shape and punctation, and elytral sculpture.Variation of these characters apparently combine at random without any notablephenotypic, populational, or geographic correlation.

Males (234). Intermediate examples in elytral coloration are perceptible ina small percentage of males from the more extensively sampled populations,particularly in western Shasta County, as well as variance in the posteromedialpronotal disk being faintly infused with cupreous red to reddish-brown primarilywhen viewed under magnification (.253). These specimens are well within thediagnostic range and acceptable intrapopulational variation of P. hovorei. Dorsalcoloration in Pleocoma is often subject to transitional phenotypic variance andrarely, if ever, may be employed exclusively as species-diagnostic. This subtlecolorational gradient may indicate a fundamental response to a divergentselective environmental regime exerted by the habitat (Baum and Larson 1991)perhaps resulting from discrete elevational, edaphic or host diversity.

Notable antennal variation is exhibited in the profile of antennomere threewhich is typically uniformly elongate, subcylindrical, and arcuate with the distalanterior apex strongly angulate. Variation being expressed in the degree ofanterior angulation which is prominent and obtuse to feebly indicated.Antennomere four is angulate anteriorly being produced as a distinct lamellateprojection which varies from 1/4 to 2/3, rarely 1/8 or 3/4, the length ofantennomere five. Antennomeres five through eleven, forming the lamellate club,are uniformly elongate and subequal in length with variation being expressed inthe outward curvature at the distal 1/3. In some specimens, being subparallel anddevoid of significant curvature with an isolated example exhibiting subsinuouslamellae.

Pronotal variation is expressed in the medial transverse ridge which istypically displayed as a raised, abrupt carina or variably reduced to a gibbous



swelling; the posteromedial impression sometimes deeply excavated or veryshallowly depressed; the longitudinal glabrous midline may be lacking, beingobscured by fine to moderate punctation; and the explanate discal surface atthe anterolateral angles may be heavily punctate to rugosely, contiguouslypunctate.

Elytral sculpture is remarkably uniform within material examined. An isolatedexample exhibits a longitudinally broken or discontinuous 3rd or 4th interval ofone elytron; the outer 4th striae sometimes evanescent or feebly indicated; themarginal bead rarely subcrenulate posteriorly.

Females (10). Interpopulational variation is remarkably stable in the fewspecimens available for analysis. Most notable variation is expressed in elytralcoloration which varies from rich reddish-brown to dark reddish brown,appearing piceous to the unaided eye. Apices of the protibial dentition mayappear blunt or worn. This condition is likely attributable to fossorial behavior.

Taxonomy. Based upon congruent synapotypic structural similarities, suggest-ing a common progenitor, P. hovorei is considered the sister species of P. staff(Figs. 3–4), at present, the only other member of the P. staff species group.

Linsley (1946) provided a provisional key to the species of Pleocoma, and todate it remains the only published key. It may be used to distinguish severalcommon species. Males of P. hovorei will key to couplet 17 where the followingmodification will serve to distinguish species:

17. Pronotum with transverse ridge feebly to moderately developed; elytralintervals distinct; confluently punctate or subrugose; striae moderate;northern Oregon. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

17(1). Pronotum with transverse ridge prominent and distinct; elytral intervalsfinely, sparsely punctate; striae moderately impressed; dorsal colorationbicolorous (pronotum piceous, elytra chestnut to reddish-brown);California: northern Sierra Nevada Mountains (Butte, Nevada, andYuba Counties) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. staff Schaufuss

17(2). Pronotum with transverse ridge moderately to prominently developed;elytral intervals deeply rugose with coarse contiguous punctures; striaedeeply impressed; dorsal coloration concolorous (pronotum and elytrablack); California: northern San Joaquin Valley to southern CascadeRange (Shasta and Tehama Counties) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. hovorei La Rue, new species

Ecology. Pleocoma species are apparently able to exploit a variety of soilconditions, slopes, exposures, and plant communities. Based upon fieldobservations, specific host plant association is not a predominate ecologicalfactor with distribution closely oriented to soil conditions. While primarilyradicicolous, larvae will consume any organic matter within the soil to the extentof consuming the soil itself under conditions of environmental stress andstarvation (F.T. Hovore, 2004, pers. comm.). Consequently, P. hovorei has beenencountered in a diversity of ecological associations.

The type locality, Black Butte Road, is situated upon a south-facing slope ofhard-packed, rocky red clay soil supporting an open yellow pine (Pinus sp.) forestwith an understory of mixed manzanita scrub (Arctostaphylos sp.) adjacent toa small residential area. Males were taken at black light traps and lights of privatedwellings, with larvae and a paratype female being dug from the soil beneathArctostaphylos manzanita Parry.



The various Redding sites are located within residential or commercial areassurrounded by remnants of oak (Quercus sp.) and pine woodland and introducedornamental vegetation.

Shasta City and Summit City localities are within or adjacent to residentialcommunities in pine, oak, and manzanita scrub growing in heavy, red, clay soilsintermixed with pale sandstone. Specimens were taken at lights of privatedwellings and community businesses.

The Palo Cedro site is in an area of valley oak and gray pine with an understoryof riparian and upland scrub growing on heavy, clay silts adjacent to a seasonalcreek. Male specimens were taken primarily within open fields beneath a scatteredoak-pine canopy, while females were encountered within a residential backyardlawn area far removed from the oak-pine influence.

A male collected at Dersch Road was in undisturbed scrub oak with anunderstory of mixed chaparral growing in light, loamy soil interspersed with areasof reddish clay adjacent a residential area.

Lyman Springs and Lyonsville areas are a mix of incense cedar (Libocedrus sp.)and black oak forest with an understory of buckbrush (Ceonothus sp.) in openand disturbed areas growing on rocky, red, clay soil oriented on a north-facingslope. South-facing slopes support an oak, incense cedar, and yellow pinewoodland with an understory of manzanita thickets or open rabbit brush(Chrysothamnus sp.) growing on a dark, rocky, clayish loam. A female was foundwithin an area of incense cedar, while males were taken in open pine and oaks.

The small hamlet of Ponderosa Sky Ranch is a continuation of the Lyonsvillewoodland community with similar soils. Males were taken at lights of privatedwellings and community businesses.

Adult Behavior. Males of P. hovorei fly most numerously at daybreak in light toheavy rainfall with continued activity over subsequent mornings and dusk with orwithout precipitation. Females were excavated at depths of 30–60 cm, often withone to three males still within the plugged burrow above. The allotype female wasencountered on the soil surface with antennae extended in an exposed lawn areain late morning following a night of precipitation.

Because of topography and elevation, the upper San Joaquin Valley receivesless precipitation in contrast to the higher environments of the southern CascadeRange. Consequently, adult activity generally starts over a month earlier in theLyonsville area as compared to the type locality at Black Butte Road and PaloCedro localities. The atypically late appearance of the few specimens in Februarymay be attributable to winters with a prevailing El Nino climatic regime indicatedby aberrant precipitation patterns and delay of suitable conditions that are part ofan assemblage of stimuli influencing adult emergence and activity. These lateappearances are indicative of phenotypic plasticity (Schlichting and Smith2002:190).

Remarks. Pleocoma hovorei is the species reported by Linsley (1945:113–114)from near Lyonsville, Tehama County, and Hovore (1977:231, 1981:2) fromRedding, Shasta County.

Etymology. It is a privilege to name this new species in honor of the late FrankT. Hovore, eminent coleopterist and foremost authority of the genus Pleocoma,and for the many years of friendship and encouragement he gave me.

Acknowledgments

The generous contributions and assistance of several individuals have greatlyenhanced this paper. The author extends his gratitude to L.R. Bronson (Summit



City, CA), M.K. Fowler (Redding, CA), and C.R. Smith (Anderson, CA) andtheir families for hospitality, lodging, specimens, field assistance and data. Thelate F.T. Hovore for discussions on Pleocoma taxonomy and bionomics, earlymanuscript comments and unpubl. data cited herein. G.E. Ball (Edmonton,Alberta, Canada), and B.D. Streit (Tucson, AZ), provided pertinent literatureresources. W.B. Warner (Chandler, AZ) for photographic expertise; S. McCleve(Douglas, AZ), B.C. Ratcliffe (Lincoln, NE), and W.B. Warner (Chandler, AZ)kindly reviewed the manuscript and offered constructive editorial suggestionstoward its improvement.

Literature Cited

Baum, D. A., and A. Larson. 1991. Adaptation reviewed: a phylogenetic methodology forstudying character macroevolution. Systematic Zoology 40:1–18.

Hovore, F. T. 1977. New synonymy and status changes in the genus Pleocoma LeConte.Coleopterists’ Bulletin 31(3):229–238.

Hovore, F. T. 1981. Notes on Pleocoma LeConte. Part II. Scarabaeus: A newsletter for thoseinterested in Scarabaeidae (A. R. Hardy, D. C. Carlson, and W. D. Edmonds,editors). November 1981. Issue #5. 6 pp.

Linsley, E. G. 1945. Further notes on some species of Pleocoma. Pan-Pacific Entomologist21(3):110–114.

Linsley, E. G. 1946. A preliminary key to the species of Pleocoma. Pan-Pacific Entomologist22:61–65.

Schlichting, C. D., and Smith, H. 2002. Phenotypic plasticity: linking molecular mechanismswith evolutionary outcomes. Evolutionary Ecology 16:189–211.

(Received 6 March 2007; accepted 16 April 2007. Publication date xx July 2007.)

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