Hylesinus

Type species

Hylesinus crenatus Fabricius

Adapted from Wood 1982, p. 110-119

Diagnosis

In general, North American Hylesinina are similar to Scierus LeConte in the Hylastina, but their procoxaeprocoxae:
extra segment occasionally preceding coxa (hip joint) of the first or anterior pair of legs of arthropods
are less widely separated than in those species. In its subtribe, Hylesinus can be easily distinguished by characters of the anterior margin of the eye which is sinuatesinuate:
descriptive of a narrow and winding thin structure or margin of a feature
in Hylesinus, entire in Hylastinus Bedel, and emarginateemarginate:
notched or indented
in Alniphagus Swaine. It can also be distinguished by having a patterned coloration, due to the light and dark colored scale-like setaescale-like setae:
setae that are wider than hair
that cover their bodies.

Description

Species in this genus range from 1.8 to 4.0 mm in length and are 1.8 to 2.0 times as long as wide. The pronotumpronotum:
the upper or dorsal surface of the first thoracic segment
is wider than long and usually armedarmed:
having a sclerotized surface structure, giving a rough texture; may serve as defense
on the anterolateral areas by coarse asperitiesasperities:
pertaining to surface roughenings or dot-like elevations that are not pointed
. The scutellumscutellum:
a shield-like bony plate or scale, as on the thorax of some insects
is small. The anterior margin of the elytraelytra:
the two external and hardened or sclerotized forewings of adult Coleoptera, often appearing leather-like in texture
is armedarmed:
having a sclerotized surface structure, giving a rough texture; may serve as defense
by a row of overlapping crenulationscrenulations:
structures on the surface of the integument an having irregular, wavy, or serrate outline
. The declivitydeclivity:
the apical portion of the beetle elytra that slopes downward
is convex. The vestiturevestiture:
a surface covering of scales or setae on the body, wing, or other appendage
consists of a mixture of white, light brown and/or black scales in a variety of patterns. The anterior margin of the compound eye is sinuatesinuate:
descriptive of a narrow and winding thin structure or margin of a feature
. The scapescape:
the first and basal segment of the insect's antennae
is usually as long as the 7-segmented funiclefunicle:
the antennal segments located between the scape and the club in some Coleoptera
. The clubclub:
the apical segment of the insect antennae that is enlarged or thickened such that it is anatomically differentiated from the preceding segments
is large and ovateovate:
egg shaped, with the narrow end apically
with three straight suturessutures:
a seam or seam-like line of contact between two sclerites or hardened body parts immovably connected
. The procoxaeprocoxae:
extra segment occasionally preceding coxa (hip joint) of the first or anterior pair of legs of arthropods
are subcontiguoussubcontiguous:
pertaining to adjacent structures, margins, or surfaces that are in contact but are not united or fused
.

Distribution

North America to Guatemala, Europe, and Asia to Australia

World fauna

Number of species: 39, Native species: 7, Introduced species: 0

Hosts

Fraxinus, Juglans, Olea, Quercus, Ulmus, among others