Usechimorpha

Diagnostic Features

Description

Antennaeantennae:
paired, segmental appendages, borne one on each side of head, functioning as sense organs and bearing a large number of sensilla.
11-segmented with a 3-segmented club. Antennal setation sparse. Subantennal groovessubantennal groove:
groove or concavity lying below the antennal insertion and housing the base of the antenna. Placed between the eye (if present) and the mandibular articulation, and sometimes extends below or behind the eye.
absent. Eyes well-developed, elongate-oval, somewhat reniformreniform:
kidney-shaped.
, coarsely faceted, extending well onto dorsal portion of head. Submentum in male with a setose pit. Pronotumpronotum:
dorsal portion of the pronotum, lying above the lateral pronotal carinae when these are present.
with anterolateral antennal cavities/grooves located above lateral margin, clearly visible from above. Pronotumpronotum:
dorsal portion of the pronotum, lying above the lateral pronotal carinae when these are present.
narrowed anteriorly, distinctly margined laterally. Pronotal discpronotal disc:
the area of the pronotum which is visible dorsally and usually delimited laterally by the two lateral carinae. Contrasted with the paired pronotal hypomera, which extend onto the ventral surface.
distinctly setose. Procoxal cavitiesprocoxal cavities:
external closure: Externally closed when the postcoxal processes of the hypomera meet the prosternal process or meet one another.
open. Metacoxaemetacoxae:
the coxae of the metathorax.
widely separated, separation as wide as metacoxal length. Abdominal ventriteabdominal ventrite:
visible ventral abdominal sclerite. Ventrite number does not correspond to true sternite number except in rare cases where sternite 1 is visible. Also called ventrite.
5 with a thin preapical groove. Tarsal formulatarsal formula:
the number of tarsomeres on the fore, mid, and hind tarsi, respectively.
5–5–4. Dorsal surface with patches of short, thick, pale setaeseta:
a sclerotized, hairlike (or scalelike) projection of cuticula arising from a single trichogen cell and surrounded at the base by a small cuticular ring.
. Dorsal and ventral surfaces commonly encrusted with dirt and debris.

Similar Genera

The genus Usechimorpha is similar to the genus Usechus. Usechimorpha can be readily distinguished by the more abrupt and compact antennal clubantennal club:
an enlarged portion of the antennal apex, consisting of a variable number of antennomeres (often 3). In an incrassate, antenna the antennomeres gradually enlarge towards to apex, but if there is an abrupt change in length or width at some point, then the antennomeres beyond this are considered to be part of the club.
, open procoxal cavities, truncate apexapex:
end of any structure distad to the base.
of the prosternal process, and the posterolateral depressions of pronotum connected by a transverse groove at the base. In Usechus, the antennal clubantennal club:
an enlarged portion of the antennal apex, consisting of a variable number of antennomeres (often 3). In an incrassate, antenna the antennomeres gradually enlarge towards to apex, but if there is an abrupt change in length or width at some point, then the antennomeres beyond this are considered to be part of the club.
is less compact, the procoxal cavities are closed, the apexapex:
end of any structure distad to the base.
of the prosternal process is distinctly widened, and the posterolateral depressions of pronotum are not connected by a transverse groove at base.

North American species

Usechimorpha barberi Blaisdell, 1929Blaisdell, 1929:
Blaisdell FE. 1929. A revision of the beetles of the tenebrionid tribe Usechini, with descriptions of a new genus and new species. Proceedings of the United States National Museum 75 (19): 1-14.
, U. montanus Doyen and Lawrence, 1979Doyen and Lawrence, 1979:
Doyen JT and Lawrence JF. 1979. Relationships and higher classification of some Tenebrionidae and Zopheridae (Coleoptera). Systematic Entomology 4: 333-377.

Known Distribution

Northwest (OR), Southwest (CA) USA; Vancouver Island, British Columbia, Canada.

Biology

Usechimorpha has been collected sifting leaf litter and detritus in conifer forests and from decaying fruiting bodies of Laetiporus sulphureus (Polyporaceae).

Abundance: Moderately rare.

Species Diagnosis

Usechimorpha barberi: Clypeus densely setose. Elytra with a number of setose tubercles. Elytral setae distributed throughout, but more dense on elytral tubercles. Distribution: California, Oregon, USA; British Columbia, Canada.

Usechimorpha montanus: Clypeus sparsely setose or glabrous. Elytral intervals 1, 2, and 4 regular, not carinate. Elytral setae more or less evenly distributed. Distribution: California, USA.

Potential Problems with Identification

Members of this genus are frequently encrusted with dirt and other debris which may conceal the diagnostic characters.

Selected References

Blaisdell (1929)Blaisdell (1929):
Blaisdell FE. 1929. A revision of the beetles of the tenebrionid tribe Usechini, with descriptions of a new genus and new species. Proceedings of the United States National Museum 75 (19): 1-14.
, Boddy (1965)Boddy (1965):
Boddy, D.W. 1965. Zopheridae. Pp. 77-79. In: M. H. Hatch, ed. The beetles of the Pacific Northwest. Part IV: Macrodactyles, Palpicornes and Heteromera. University of Washington Publications in Biology, 16 (4): 1-268.
, Doyen and Lawrence (1979)Doyen and Lawrence (1979):
Doyen JT and Lawrence JF. 1979. Relationships and higher classification of some Tenebrionidae and Zopheridae (Coleoptera). Systematic Entomology 4: 333-377.
, Ivie (2002c)Ivie (2002c):
Ivie, M.A. 2002c. 129. Zopheridae, pp. 457-462 In: R. H. Arnett, Jr., Jr. and M. C. Thomas (eds.), American Beetles. CRC Press, Gainesville, Florida.
, Ślipiński and Lawrence (1999)Ślipiński and Lawrence (1999):
Ślipiński, S.A. and J.F. Lawrence. 1999. Phylogeny and classification of Zopheridae sensu novo (Coleoptera: Tenebrionoidea) with a review of the genera of Zopherinae (excluding Monommatini). Annales Zoologici (Warszawa), 49: 1-53.

 Usechimorpha barberi  Blaisdell, 1929
Usechimorpha barberi Blaisdell, 1929
 Usechimorpha montanus  Doyen and Lawrence, 1979
Usechimorpha montanus Doyen and Lawrence, 1979