Heterachthes

Subfamily

Cerambycinae

Diagnosis - adult

Body length: 5.5–11.5mm. 
Eyes: eye interommatidial setaeseta:
a sclerotized hair-like projection of the cuticle
absent, eye deeply emarginateemarginate:
notched at the margin
> half width, eye ommatidial density coarse. 
AntennaeAntenna:
in larval and adult insects, paired segmented appendages, borne one on each side of the head, functioning as sense organs and bearing a large number of sensilla
: antennal length reaching/surpassing end of body, antennal flagellar segments elongateelongate:
much longer than wide
, scapescape:
the first proximal segment of the antenna
smooth/punctate at apexapex:
end of any structure distad to the base
, antennal segment 3 > scapescape:
the first proximal segment of the antenna
. 
Pronotumpronotum:
the upper and dorsal part of the prothorax
: pronotumpronotum:
the upper and dorsal part of the prothorax
shape longer than wide, pronotumpronotum:
the upper and dorsal part of the prothorax
lateral armature absent or blunt tubercule. 
Prosternum: prosternal process dilated at apexapex:
end of any structure distad to the base
, procoxal cavities open posteriorly, rarely closed posteriorly. 
ElytraElytron:
the leathery forewing of beetles, serving as a covering for the hind wings, commonly meeting opposite elytron in a straight line down the middle of the dorsum in repose
: elytral length reaching or close to end of abdomen, elytral apicesapex:
end of any structure distad to the base
rounded or truncatetruncate:
cut off squarely at the tip
, emarginateemarginate:
notched at the margin
, rarely with tooth or spinespine:
a protuberance with an acute (sharp) distal end
, elytral color black, brown, or reddish, elytral color pattern present. 
Legs: visible tarsomeres: 4, femora clavateclavate:
thickening gradually toward the tip
, rarely slender, protibial spurs: 2, tarsal claws simple. 

Tribe Ibidionini: Form very elongated, slender. Head with front small, perpendicular; mandibles short, acute; palpi short, a little unequal, last segment expanded; eyes large, coarsely faceted; antennaeantenna:
in larval and adult insects, paired segmented appendages, borne one on each side of the head, functioning as sense organs and bearing a large number of sensilla
elongate, slender in female, thickened basally in male, sparsely punctured and pubescentpubescent:
downy; clothed with soft, short, fine, loosely set hair
. Thoraxthorax:
the middle body segment in insects which bears the legs and wings, consists of the pro-, meso-, and meta- thorax
with anterior coxae small, rounded, cavities closed or narrowly open behind; intermediate coxal cavities closed, not angulated externally; metathoracic episternumepisternum:
the aspect of a thoracic pleuron dorsal to the coxal cavity and anterior to the pleural suture
narrow, parallel, odoriferous pore distinct. Legs with femora clavateclavate:
thickening gradually toward the tip
; tibiaetibia:
the leg segment distal to the femur, proximal to the tarsus
carinate or not. Elytral apicesapex:
end of any structure distad to the base
unarmed (Ibidionini description, Linsley 1963Linsley 1963:
Linsley, E.G. 1963. The Cerambycidae of North America. Part IV. Taxonomy and classification of the subfamily Cerambycinae, tribes Elaphidionini through Rhinotragini. University of California Publications in Entomology, Vol. 21. 165 pp.).

Similar genera

other New World Neoibidionini

Differential diagnosis

The spineless metafemorametafemur:
hind femur
, procoxal cavities slightly open, emarginateemarginate:
notched at the margin
eyes with a well-developed dorsal lobelobe:
a rounded projection or protuberence
, and metatibiae without carinaecarina:
an elevated ridge or keel, not necessarily high or acute
will distinguish Heterachthes from many other Neoibidionini.

Distribution

Nearctic, Neotropical

Recorded host plants

broadleaf; Pinus spp.; Carya, Liriodendron, Prosopis, Carpinus, Quercus, Acacia

Remarks

70 species. Only H. ebenus known from conifers. Larvae bore in dead branches.

Synonyms

Heterachtes Aurivillius, 1912, Coleopterorum catalogus, 39: 110

Heterachthon Thomson, 1867, Physis, 1: 134, 138 (emendation)

Brydaeon Thomson 1867

Ibidion Thomson 1867

Taxonomy

Heterachthes Newman, 1840, Entomologist, 1: 9