Ips hunteri, frons
Ips hunteri, declivity
Ips hunteri, lateral habitus

Scientific Name

Ips hunteri Swaine, 1917

Diagnostic notes

-Has four spines on the elytral declivity and appears similar to I. borealis.
-Potentially sympatric with closley related species I. pilifrons, I. borealis and morphologically similar species I. pini.
-Differs from the related species by lack of frontal sexual dimorphism and from I. pini by uniseriately punctured discal interstriae.
-Using sexual dimorphism for identification requires either genitalic dissection or collection of males and females from a single gallery.

Morphological Summary

sexes combined
Body. 3.3-4.5 mm long, 2.5-2.6 times longer than wide; pronotum 1.0-1.2 times longer than wide.
Head. Epistomal margin with uniseriate row of tubercles with gap at midline. Frons outline convex in lateral view; vestiture fine (not hiding part of integument); surface sculpture near epistoma densely tuberculate-punctate; central carina absent; central tubercle absent; transverse carina absent; frons central fovea absent; circular tubercles above top of eyes present - up to one third of all tubercles. Vertex and pronotum without stridulatory apparatus (pars stridens). Antennal club sutures bisinuate.
Prothorax. Protibiae with three socketed teeth on apical half (does not include apical spine).
Elytra. Interstriae punctate (observed on interstriae 2 and 3 on middle third of elytral disc), punctures 0.5-0.7 times diameter of adjacent strial punctures (punctures and striae measured at steepest part of puncture wall), interstrial setae longer than width of scutellar shield, interstriae 3-5 times as wide as adjacent striae. Elytral declivity with four spines per side, spine 3 largest; spine 1 (largest on 2nd interstria) closer to suture than spine 2; spines 1 and 2 separated at base by distance greater than height of spine 1; spine 2 closer to spine 3 than spine 1; spine 3 pedunculate (capitate), apex acute, with apical half asymmetrical in lateral view; spines 2 and 3 not on shared tumescence, in line with spines 1 and 4 (posterodorsal view); declivital integument shiny.

Geographic Distribution

USA (Arizona, Colorado, Utah).

Hosts

Picea spp. Principally Picea pungens.

Notes

I. hunteri, and I. perturbatus form clade (Cognato and Sun 2007).

References

Cognato, A.I.2015. Biology, systematics, and evolution of Ips. In Bark beetles: biology and ecology of native and invasive species. Edited by F.E. Vega and R.W. Hofstetter. Elsevier, San Diego, California. Pp. 351–370.

Cognato, A.I. and Sun, J.H. 2007. DNA based cladograms augment the discovery of a new Ips species from China (Coleoptera: Curculionidae: Scolytinae). Cladistics, 23: 539–551.

Wood, S.L. 1982. The bark and ambrosia beetles of North and Central America (Coleoptera: Scolytidae), a taxonomic monograph. Great Basin Naturalist Memoirs, 6: 1–1359.

Internet resources

https://www.barkbeetles.info/regional_chklist_target_species.php?lookUp=1711