Arixyleborus mediosectus

Taxonomic history

Xyleboricus mediosectus Eggers, 1923: 215.

Arixyleborus mediosectus (Eggers): Schedl, 1958c: 145.

Synonyms

Arixyleborus angulatus Schedl, 1942a: 183. Wood, 1989: 170.

Diagnosis

1.9−2.1 mm long (mean = 1.98 mm; n = 5); 2.86−3.33 times as long as wide. This species is distinguished by the protibiaprotibia:
tibia of the first pair of legs
posteriorposterior:
toward the rear end; opposite of anterior
face inflatedinflated:
blown up; distended
and granulate; antennalantennal:
pertaining to the antennae
club broader than tall; pronotumpronotum:
the dorsal surface of the thorax
laterallateral:
pertaining to the side
margin oblique; pronotumpronotum:
the dorsal surface of the thorax
anterioranterior:
the front or forward; opposite of posterior
margin without serrations; and posterolateralposterolateral:
relating to end of the side part/portion
carinacarina:
an elevated ridge or keel, not necessarily high or acute
acute, granulategranulate:
pertaining to a coarse, grainy surface texture
.

It can be further distinguished from the closely related A. silvanus by the more elongate form (2.6–2.7 times as long as wide in A. silvanus), more elongate pronotumpronotum:
the dorsal surface of the thorax
(1.3 × longer than wide vs 1.1–1.2 times in A. silvanus), the more finely granulategranulate:
pertaining to a coarse, grainy surface texture
interstriae, and shallowly impressedimpressed:
a depression in a surface
striae at the apexapex:
point or edge furthest from the body; opposite of base
of the elytralelytral:
pertaining to the elytra
discdisc:
the flat central upper surface of any body part (e.g. pronotum and elytra)
, and the presence of short coarse setaeseta:
small hair-like or scale-like structure
on the declivitydeclivity:
downward slope of either the pronotum or elytra
rather than fine hair-like setaeseta:
small hair-like or scale-like structure
. It can be further distinguished from the closely related A. crassior by the more elongate form (2.5 times as long as wide in A. crassior) and short coarse setaeseta:
small hair-like or scale-like structure
on the declivitydeclivity:
downward slope of either the pronotum or elytra
.

May be confused with

Arixyleborus crassior, A. phiaoacensis, and A. silvanus

Distribution

‘Borneo’, Cambodia, India (Andaman Is, Assam), Indonesia (Sumatra), Laos, East & West Malaysia, Philippines, Sri Lanka, Thailand, Vietnam

Host plants

polyphagous (Maiti and Saha 2004Maiti and Saha 2004:
Maiti PK, Saha N. 2004. Fauna of India and the adjacent countries. Scolytidae: Coleoptera (bark and ambrosia beetles). Vol. 1. Part 1. Zoological Survey of India, Kolkata, 268 pp.); It has also been collected from the crop of an edible-nest swiftlet (Collocalia fuciphaga) (Beaver and Browne 1978Beaver and Browne 1978:
Beaver RA, Browne FG. 1978. The Scolytidae and Platypodidae (Coleoptera) of Penang, Malaysia. Oriental Insects 12: 575-624. https://doi.org/10.1080/00305316.1978.10432538).

DNA data

Sequences available for COI and CAD.

COI: OP617796

CAD: OP607226