Cephennium aridum Hopp & Caterino,

Hopp, Katie & Caterino, Michael, 2009, Seven new species of Cephennium Müller & Kunze (Coleoptera, Staphylinidae, Scydmaeninae, Cephenniini) from California with a key to native North American species, ZooKeys 24 (24), pp. 31-54: 48-50

publication ID

http://doi.org/ 10.3897/zookeys.24.247

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scientific name

Cephennium aridum Hopp & Caterino

sp. n.

Cephennium aridum Hopp & Caterino  , sp. n.


Figs 1H, 2H, 3H, 4D, 5F, 6

Type Material. Holotype. Male. “CA: San Bernardino Co.; 34.1405°N, 116.4541°W; UC Burns Reserve ; Railroad Cyn, IV.1.2008; sifted from grass & flood debris; M. Ca-GoogleMaps 

debris; M. Caterino & R. Leschen”/ “CA BEETLE PROJ; CBP 0072926” ( SBMN [gold coated for SEM]).

Paratypes (9): “CALIF: Riverside Co ; 4mi SE Valle Vista; II-1978 K.Cooper; Oak litter 78-57”/ “ CEPHENNIUM  ; spp.; S. O’KEEFE DET ‘90” (1 SBMN)  ; “CALIF: Riverside Co ; Palm Canyon Aqua [sic]; Caliente Reservation; IV-27-1978 78-67; K.W.Cooper ”/ “berlese litter; at base of Washingtonia filifera  ” (1 CSCA)  ; “CALIF: Riverside Co.; Whitewater cyn. Palm Oasis; V-4-1987 to XI-27-1988; Rolf L. Aalbu coll.”/ “Ethylene-glycol pitfall; trap at base of Washingtonia filifera  ” (2 CSCA)  ; “CAL- IF: Riverside Co.; 2 mi. E Gilman Hot; Springs , Lamb Canyon; V-18-1978 / XI-13- 1979; Fred G. Andrews; Antifreeze pit trap ” (5 CSCA)  .

Etymology. This species name refers to its occurrence in the arid regions of the western Mojave/ Colorado desert transition zone.

Diagnosis. This species can be immediately distinguished from all of its California congeners by the presence of a single ommatidium on each side of the head ( Fig. 4DView Figure 4). Besides this somewhat cryptic character, C. aridum  shares a sharply angulate humeral process only with C. urbanum  . Th e mesosternal keel of C. aridum  , however, has scalelike microsculpture between the mesocoxae ( Fig. 2HView Figure 2), whereas that of C. urbanum  has only setose punctures between the coxae, its scale-like microsculpture being restricted to the extreme anterior end ( Fig. 2GView Figure 2). Th e mesosternal process of C. urbanum  is also distinctly crescent-shaped ( Fig. 2GView Figure 2), where that of C. aridum  is angulate ( Fig. 2HView Figure 2).

Description. Male. Length: 0.817 –0.912 mm; pronotal width: 0.304 –0.342 mm; elytral width: 0.352 –0.418 mm. Body elongate, slender, weakly convex; amber-yellow, translucent; evenly and moderately pubescent; pubescence golden, slender, moderately long, weakly decumbent (Fig. 1H). Dorsal surface of head smooth, sparsely pubescent, narrowing anteriorly from antennal insertions. Single ommatidium present on each side of head ( Fig. 4DView Figure 4). Antenna setose, antennomeres I and II longer than broad, antennomeres III-VI quadrate and smaller than antennomeres II and VII, antennomere VIII smaller than antennomeres VII and IX, antennomeres IX-XI gradually clavate forming a loose club. Pronotum moderately pubescent, broadest between middle and anterior third, very convex in disc part and moderately flattened near each posterior angle; anterior margin not visible from above; anterior and posterior margin lacking marginal bead; marginal bead complete laterally, gradually widening towards base; lateral edge broadly rounded to posterior third, then weakly sinuate to base (Fig. 1H). Hypomeron smooth, sparsely setose towards anterior quarter and along outside (lateral) edge. Prosternum with small, weakly protruding, oblique narrowly ovate nodules anterolaterad procoxal cavities ( Fig. 2HView Figure 2). Elytra smooth, lacking striae, as pubescent as pronotum, covering all abdominal segments; elytral suture absent; basomedial fovea present on each elytron; fovea small, moderately pubescent (Figs. 1H, 3H). Humeral angle of elytron projecting laterally to sharp point ( Fig. 3HView Figure 3). Scutellum weakly triangular, lacking setae ( Fig. 3HView Figure 3). Mesosternal keel sparsely setose, with scale-like microsculpture over most of its length, abruptly smooth in posterior extreme, apex moderately bifid, divergent projections short, diverging at ̴90° an- gle ( Fig. 2HView Figure 2). Metathoracic wings vestigial. Femora strongly clavate in distal half; tibiae expanded and becoming more densely setose towards distal half. Five visible abdominal sternites, ventrites V and VI largely fused. Aedeagus with median lobe bulbous, heavily sclerotized, truncate at apex, with very short median dorsal process, weakly emarginate for reception of apex of apical digiform process; apical collar not apparent; dorsal parameres slender, extending well beyond end of median lobe, each with two subapical setae (Fig. 1H).

Female. Unknown.

Biology. The type of this species was sifted from grass and flood debris in a small, spring-fed, but frequently dry drainage. Other specimens were sifted from litter of the native California Fan Palm ( Washingtonia filifera  ), which also occur in scattered springfed drainages in the Colorado (and broader Sonoran) desert.

Distribution. This species is known from several localities in the far northeastern Colorado desert, in San Bernardino and Riverside Counties, CA (Fig. 6).


California State Collection of Arthropods