M. W. Blackman.
Notes on Forest Insects. III Two New Species of Pytophthorus from Colorado.
Psyche 27:1-5, 1920.

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PSYCHE
VOL. XXVII EBUARY, I920 No. I
NOTES ON FOREST INSECTS.
111. TWO NEW SPECIES OF PITYOPHTHORUS FROM COLORADO.
BY M. W. BLACKMAN, PE.D.,
Professor of Forest Entomology, New York State College ,of Forestry, Syracuse, N. Y.
Pityophthorus bassetti sp. nov.
Reddish brown $23 times as long as broad. Male-length 2.2 mm. The j~ont with distinct elevated trans- verse carina at level of upper inner angle of eye; above carina coarsely punctured, somewhat rugose and shining; below carina slightly excavated, more finely and densely punctured with mod- erately short and fine hairs; epistomal margin bordered with longer, coarser hairs; eye8 rather elongate oval, not coarsely granular, with anterior emargination as broad as deep; antenna1 club short oval with segments sub-equal, first suture straight, second and third procurved ventrally; outer part of funicle one third longer than pedicel.
Pronottdm very little longer than broad, sides of basal half nearly parallel but widest at the middle and very slightly arcuate; front broadly rounded and rather weakly serrate on the margin; anterior half armed with moderately coarse, acute asperities which are often arranged in fairly regular concentric lines, with their bases often continuous; summit fairly prominent with slight but distinct transverse depressed area immediately posterior to it which is divided by a smooth slightly elevated median area and bordered laterally by fainter elevated lines; depression more deeply and densely punctate; punctures becoming finer and sparser poster- iorly and finer laterally; basal marginal line fine but distinct, slightly sinuate. Ventral surface of prothorax grooved and smooth behind but distinctly punctured with fine hairs in front.



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Elpfra equal in width to the thorax; sides nearly paraIlq1 but slightly widest near middle, suddenly and strongly rounded behind origin of the declivity with tips subaminate; strial punctures moderately large and deep, not entirely ~ l a r near suture; strite not impressed; interstitid punctures very qame and of moderate &e; nearly glabrous above but with a few fine Fig. 1. 1, Dod view of d e paratype of Pi&qvhhw bmeUi, ap. mv., ma@d 11 diametem; 9, lateral view of nude, rnagnifid 1% &metem; 3, front wiew of hkd of femak showing the circdm pubcent m a bdd by Iotger and m e r hairs, mngnified 3% dimnetem.
short hairs, these becoming more abundant and longer at sides and behind. Declivity step with deep wide sulcua; suture .wide, *
elevated, with several coarse granules near apex; lateral elevations with fairly &wp serrate edge mned with 10 to 12 moderate sized, black teeth, each with a stiff tactile hair arising from its he? bwe. Last ventral abdominal segment deeply and very broadly emarginate-
Female, slightly longer (2.4 mrn.1 and of same width. Differs from male in having the from very slightly concave, with a nedy ckhr area fmely and densely punctured and pubescent and bordered with longer coarser incurved hairs. Elytra mu& 1- hairy at sides and rear than in male, hteral elevations of the declivity with serrations of the male mplwed by a sparse row of minute granules, long tactile hairs absent. Pitkin, Co~oxdo.
Bred from material brought in by Mr.
R. 0. Bassett, Jr.
Host tree: Picea mgdrnami Erigelrn. Will also bred sue- cessfuHy in Abies balmma (LinnJ Miller.




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lwl Bhhan--Ntw Spcim oj Pdgophihom fmm Color& 3 The materid from which payophtbu8 bmaefti wa.9 bred con- si~ts of several slabs teken from the base of an Engelmmn spruce near Pith, Ghdo by Mr. R. 0. Bassett, Jr., a former student. These were received at Syracuse Nov, 93, 1915 and upon exami- nation the bark was, found to contain numerous living newly full grown law% of a sdytid. Purther examination yielded the dead parent beetles and these proved to be an unknown speck of Fityophthorus. The shhs were placed in a breeding jar in the hbQEbbTy and a considerable number of beetles emerged during the fir& two wwks of Decembr, Part of these were preserved aa apechen3 while the rest were left in the breeding jar md several pieces of a fmddy mt limb of bdsam fir about 3 inch in diameter were, introduced. The adults readily entered not only the fresh bdsm, but also some reented the dabs of Engdmam spruce from which they had emerged-breeding in both. The new second genemtion of adults emerged from these two hosts durin~ the summer of 1916 and mmy of them were still dive in September, at which time also a few small lww doubtless of a third generation were found, It wodd appear that n o ~ ~ l y there is not more than ope gemrat& per year.
The bark on the Engelmmn spruce in which the beetles originally bred was about I% of an inch thick, while that of the balsam limbs to which the new bmd readily trmsferred was only of an inch thick. In the former the larvze worked nearly entirely in the inner and middle bark usually not even grooving the sapwmd while in the latter the larval mines were excavated partly from the sap- wood. hide from this the engravinpp in the two are similar, Ih their general char~rktics the engraving is not unlike those of other species of this genus, It consists of rn entrance gallery led- ing diagonally upward ad inward b the jnuction of bark and sap mod where it is expaded into an irregdm nuptial chamber. Fmm this a variable number of egg-galleries branch OR from a11 ~ides, but these soon hke a genera1 longitudinal dimtion. In number the egg-galleries vary from 4 to 9 wid the average in 13 engravings in balstm fir is 6.9. The efl& of this 1-e proportion- ate number of female to each male upon their relative fecutulity could not be determined aatisfaebrily because of the injurk ta the engravings by the numerous brood.
The egggalleries which have a general longitudhd direction are



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4 Psyche [February
not excessively long when compared with those of several other species of this genus. In the material at hand they vary from 3+ cm. to 7 cm. with an average length of 4.2 cm. The egg niches, where these are still recognizable, occur on both sides of the gallery and are not closely arranged-usually being 2 mm. or more apart so that the number of eggs laid by each female is probably not great.
Pityophthorus occidentalis sp. nov.
Reddish brown to nearly black in color; 2.8 times as long as broad.
Male. Length 2.5 mm. Front convex with distinct rough transverse carina below ler7el of upper inner angle of eyes, coarsely and roughly punctured above, slightly excavated and more finely punctured below carina, with distinct median vertical carina from transverse carina to margin of epistoma; fine short hairs over entire front but becoming more conspicuous cephalad; edge of epistoma emarginate and bisinuate, bordered with coarser and longer hairs; eyes oval with rather wide and deep emargination; antenne light reddish-brown, club oval, with first three sefments sub-equal and fourth segment shorter; first and second sutures on ventral face nearly straight, third strongly arcuate; outer part of funicle one-half longer than pedicel.
Pronoturn slightly longer than broad (14 :l3), widest behind the summit; sides of basal half slightly arcuate, faintly constricted in front of middle, broadly rounded in front, with distinct nearly regular serrations, slightly more than the cephalic half armed with well developed asperities arranged in concentric nearly regular rows; summit prominent; posterior area shining, with rather numerous moderate sized punctures, except on the impunctate slightly elevated area in the.median line; basal marginal line dis- tinct and continued diagonally downward along the sides as a mar- gined ridge easily distinguishable to a point anterior and dorsal to the base of the prothoracic leg. Ventral surface of the prothorax punctured in front, smooth behind except immediately adjacent to the base of the leg.
Elgtra of same width as prothorax; sides subparallel, widest before the middle, slightly narrowed behind the middle to the level of the origin of the declivity, from which point it is strongly and



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19201 Blackman-New Species of Pityophthorus from Colorado 5 regularly rounded; tips not acuminate; stria1 punctures moderately fine, in regular rows except near base where they are somewhat con- fused, first stria impressed, the others not; interstrial punctures fine and very sparse, almost lacking on the disc; disc nearly glabrous but with a few small hairs, these becoming longer and more numer- ous at the sides and behind; decli~ity steep with deep, rather narrow sulcus; suture granulate and widened toward apex; lateral eleva- tions abrupt and granulate; granules of the 3rd and 4th interspaces forming two rows which converge and become confused near apex, those of 4th interspace smaller but distinct, others more or less confused, each of granules with a rather long stiff tactile hair arising from near its base.
Ventral abdominal segments rather finely punctured and moderately hairy; last segment deeply and broadly emarginate.
Female, of the same general proportions. Front flattened, with nearly circular pubescent area bordered by coarser and longer in- curved hairs; prothorax as in male; apex of elytra more acutely rounded but not acuminate; declivity not so steep, sulcus not so deep, lateral elevations not so pronounced, with a sparse row of minute granules on the 3rd interspace and a few scattered ones lateral to it; long tactile hairs absent. Host tree: Picea engelmanni Englm.
Locality: From Pitkin, Colo., collected by Mr. R. 0. Bassett, Jr., October, 1915.
Fig. 4, 5. Slabs from the trunk of Engelmann spruce showing the engravings of P. bassetti in the inner bark and the exit holes through the outer bark. A bout two-thirds natural size. Fig. 6.
Two segments from the limb of a balsam fir, showing the engravings of P. bassetti on the surface of the sapwood. About * three-fifths natural size.




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