Pycnarthrum

Type species

Pycnarthurm gracile Eichhoff

Adapted from Wood 1982, p. 455-461

Diagnosis

Among the two genera of the subtribe Ctenophorina in southeastern USA, Pycnarthurm is distinguished from Scolytodes Ferrari by the larger and inferiorly subcontiguoussubcontiguous:
pertaining to adjacent structures, margins, or surfaces that are in contact but are not united or fused
eyes and by the abundant vestiturevestiture:
a surface covering of scales or setae on the body, wing, or other appendage
of scale-like setaescale-like setae:
setae that are wider than hair
.

Description

Species in this genus range from 1.3 to 2.1 mm in length and are approximately 2.2 times as long as wide. Their color rages from yellowish to black. The pronotumpronotum:
the upper or dorsal surface of the first thoracic segment
is as long as wide and unarmedunarmed:
having no granules, teeth, tubercles, spines, or other protective structures
, with the lateral margins raised in a line. The scutellumscutellum:
a shield-like bony plate or scale, as on the thorax of some insects
is small. The declivitydeclivity:
the apical portion of the beetle elytra that slopes downward
is convex and unarmedunarmed:
having no granules, teeth, tubercles, spines, or other protective structures
. The vestiturevestiture:
a surface covering of scales or setae on the body, wing, or other appendage
consists of abundant, short, and erect scale-like setaescale-like setae:
setae that are wider than hair
. The anterior margin of the compound eye is entire, the long eye is almost subcontiguoussubcontiguous:
pertaining to adjacent structures, margins, or surfaces that are in contact but are not united or fused
below. The scapescape:
the first and basal segment of the insect's antennae
is longer than the 6-segmented funiclefunicle:
the antennal segments located between the scape and the club in some Coleoptera
. The oval to ovateovate:
egg shaped, with the narrow end apically
clubclub:
the apical segment of the insect antennae that is enlarged or thickened such that it is anatomically differentiated from the preceding segments
is flat with two clearly visible suturessutures:
a seam or seam-like line of contact between two sclerites or hardened body parts immovably connected
(straight in P. hispidum) and a third hard to distinguish; the first suture is septateseptate:
having a septum or septa
. The procoxaeprocoxae:
extra segment occasionally preceding coxa (hip joint) of the first or anterior pair of legs of arthropods
are separated.

Distribution

South Florida, and Mexico to Brazil

World fauna

Number of species: 16, Native species: 1, Introduced species: 0

Hosts

Brosimum, Cedrela, Ficus

  Pycnathrum hispidum , dorsal view

Pycnathrum hispidum, dorsal view

  Pycnathrum hispidum , lateral view

Pycnathrum hispidum, lateral view

  Pycnathrum hispidum , posterior view (declivity)

Pycnathrum hispidum, posterior view (declivity)

  Pycnathrum hispidum , anterior view

Pycnathrum hispidum, anterior view

  Pycnathrum hispidum , club

Pycnathrum hispidum, club