Ips pilifrons sulcifrons, female frons
Ips pilifrons sulcifrons, male frons
Ips pilifrons sulcifrons, female head, lateral
Ips pilifrons sulcifrons, male head, lateral
Ips pilifrons sulcifrons, female declivity
Ips pilifrons sulcifrons, male declivity
Ips pilifrons sulcifrons, female lateral habitus
Ips pilifrons sulcifrons, male lateral habitus

Scientific Name

Ips pilifrons sulcifrons Wood, 1960

Diagnostic notes

Species:  
-Has four spines on the elytral declivity and general appearance is similar to I. borealis.  
-Potentially sympatric with related species I. borealis, I. tridens, I. hunteri, and morphologically similar species I. pini.  
-Differs from related species by deep, coarse strial punctures, large size, 3.9–5.0 mm and from I. pini by uniseriately punctured discal interstriae.

Subspecies:  
-Diagsnosable by female only.  
-Female frons strongly protuberant, elevated area with median sulcus (groove), most with dense pile-like patches of setae, and not extending above level of eyes. 4.4–5.0 mm (Wood 1982).

Morphological Summary

females
Body. 4.4-5.0 mm long, 2.4-2.6 times longer than wide; pronotum 1.0-1.1 times longer than wide.
Head. Epistomal margin with uniseriate row of tubercles absent or present with gap at midline. Frons outline protruding in lateral view; vestiture coarse and dense (hiding part of integument), with vertical groove in setal patch; surface sculpture near epistoma densely tuberculate-punctate or with isolated tubercles; central carina absent; central tubercle absent; transverse carina absent or present; frons central fovea present or absent; circular tubercles above top of eyes absent or present - up to one third of all tubercles. Vertex and pronotum without stridulatory apparatus (pars stridens). Antennal club sutures bisinuate.
Prothorax. Protibiae with three or four 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 3-4 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 or right-angled, with apical half symmetrical or asymmetrical in lateral view; spines 2 and 3 on shared tumescence, not in line with spines 1 and 4 (posterodorsal view); declivital integument shiny.

males
Body. 4.4-5.0 mm long, 2.4-2.6 times longer than wide; pronotum 1.0-1.1 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 or with isolated tubercles; central carina absent; central tubercle absent; transverse carina absent or present; frons central fovea absent; circular tubercles above top of eyes absent, present - up to, or more than one third of all tubercles. Vertex and pronotum without stridulatory apparatus (pars stridens). Antennal club sutures bisinuate.
Prothorax. Protibiae with three or four 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 3-4 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 or right-angled, with apical half asymmetrical in lateral view; spines 2 and 3 on or not on shared tumescence, not in line with spines 1 and 4 (posterodorsal view); declivital integument shiny.

Geographic Distribution

Species: Mexico (Coahuila); USA (Arizona, Colorado, Idaho, Nevada, New Mexico, Utah, Wyoming).

Subpecies: USA (Colorado, New Mexico)

Hosts

Picea engelmanii and P. pungens (Wood 1982).

Notes

I. borealis, I. pilifrons, and I. tridens 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=1723