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 distinct, 2-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.
present, grooves extent into antennal cavitiesantennal cavity:
a prothoracic cavity for housing the whole antenna or a portion of the antenna (usually the club).
on hypomeronhypomeron:
that portion of the pronotum which is visible from the ventral side; when there is a lateral pronotal carina, this is the portion below that carina (the pronotal disc being above it).
. Eyes small, reduced, coarsely faceted. 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.
convex. 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.
moderately separated, separation slightly less than metacoxal length. Elytraelytron:
the fore wing in Coleoptera, which is more or less uniformly sclerotized and in resting position is longitudinally oriented, usually meeting the opposite elytron along the midline.
fused, with weak punctate striae and carinaecarina:
an elevated ridge or keel, not necessarily high or acute.
. Tarsal formulatarsal formula:
the number of tarsomeres on the fore, mid, and hind tarsi, respectively.
4–4–4. Dorsal surface sparsely setose. Body usually encrusted with dirt or debris.
The genus Megataphrus is similar to Coxelus in having reduced eyes and wingswing (hind wing):
wings arising from the metathorax. NOTE: In many Zopherinae, the hind wings are completely absent.
absent. The presence of antennal cavitiesantennal cavity:
a prothoracic cavity for housing the whole antenna or a portion of the antenna (usually the club).
on the hypomeronhypomeron:
that portion of the pronotum which is visible from the ventral side; when there is a lateral pronotal carina, this is the portion below that carina (the pronotal disc being above it).
serve to distinguish Megataphrus.
Megataphrus arizonicus Stephan, 1989Stephan, 1989:
Stephan, K.H. 1989. The Bothrideridae and Colydiidae of America north of Mexico (Coleoptera: Clavicornia and Heteromera). Occasional Papers of the Florida State Collection of Arthropods, 6: xii + 65 pp., M. chandleri Stephan, 1989Stephan, 1989:
Stephan, K.H. 1989. The Bothrideridae and Colydiidae of America north of Mexico (Coleoptera: Clavicornia and Heteromera). Occasional Papers of the Florida State Collection of Arthropods, 6: xii + 65 pp., M. tenuicornis Casey, 1890Casey, 1890:
Casey TL. 1890. Coleopterological Notices. II. Annals of the New York Academy of Sciences 5: 307-504, illus.
Northwestern (OR), Southwestern (CA, AZ) USA.
Members of this genus are flightless and ground-dwelling. They are most commonly collected by Berlese extraction from the debris of redwood, fir, eucalyptus, laurel, chinquapin (Castanopsis), Ceanothus (Rhamnaceae) and under the bark of various stumps.
Abundance: Rarely encountered.
Megataphrus tenuicornis: Antennal cavities on hypomeron margined both on the inside and outside. Elytron with 3 carinae between suture and margin. Distribution: California and Oregon, USA.
Megataphrus arizonicus: Antennal cavities on hypomeron margined on the outside only. Elytron with 4 carinae between suture and margin. Distribution: Arizona, USA.
Megataphrus chandleri: Antennal cavities on hypomeron margined on the outside only. Elytron with 3 carinae between suture and margin. Distribution: Oregon, USA.
Members of this genus are frequently encrusted with dirt and other debris which may conceal the pronotal and elytral characters.
Casey (1890)Casey (1890):
Casey TL. 1890. Coleopterological Notices. II. Annals of the New York Academy of Sciences 5: 307-504, illus., Stephan (1989)Stephan (1989):
Stephan, K.H. 1989. The Bothrideridae and Colydiidae of America north of Mexico (Coleoptera: Clavicornia and Heteromera). Occasional Papers of the Florida State Collection of Arthropods, 6: xii + 65 pp., Ivie (2002a)Ivie (2002a):
Ivie, M.A. 2002a. 127. Colydiidae, pp. 445-453 In: R. H. Arnett, Jr., Jr. and M. C. Thomas (eds.), American Beetles. CRC Press, Gainesville, Florida.
Authors: Lord NP, Nearns EH, Miller KB. 2011–2015.
Content updated Apr 2015; taxonomy updated Feb 2026
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