T. B. Mitchell.
New Megachilid Bees.
Psyche 34:104-121, 1927.

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Psyche [April
NEW MEGACHILID BEES.1
BY THEODORE B. MITCHELL,
The species which are described below were found in two series of unidentified material, one in the collection of Professor W. M. Wheeler at the Bussey Institution, and the other in the collection of the Museum of Comparative Zoology at Cambridge. Lithurgus bruesi n. sp.
3. Head broader than long, the eyes converging slightly below, pubescence entirely greyish-white; supraclypeal plate shining, almost impunctate medially, with scattered punctures laterally; clypeus impunctate medially except for a few scat- tered punctures, but closely punctate laterally, practically rugoso-punctate, the apical margin smooth and entire; labrum very peculiar and distinctive, having a deep longitudinal im- punctate channel or concavity, which has on either side midway a strong triangularly pointed spine, the distance from the bottom of the concavity to the tip of the spine being equal to about half the length of the labrum; mandibles ordinary, with three sub- equal teeth; cheeks about as broad as width of eye, the posterior margin above quite sharp but hardly carinate, closely and finely punctured; vertex slightly rounded, closely and rather finely punctured, the punctures between the eyes and ocelli large, deep and distinctly separated; lateral ocelli very slightly nearer edge of vertex than to nearest eye; antennae shining above, dark, the joints more ferruginous apically, dull brownish-red below, the joints slightly longer than broad, the first joint of the flagellum and the basal half of the second joint, below, blackish. Thorax with pubescence entirely greyish-white, longer at' sides and behind; mesonotum and scutellum extremely densely and quite finely punctured, the punctures of the pleura also Tontribution from the Department of Zoology and Entomology, North Carolina State College, in cooperation with the Entomological Laboratory of the Bussey Institution, Harvard University (Bussey Institution, No. 273). Published with the approval of the Director of the North Carolina Ex- periment Station as paper number 15 of the Journal Series.



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19271 New Megachilid Bees 105
being very close and quite fine; propodeum with minute close punctures laterally, more sparse behind, the surface tessellate, basal triangle not definitely demarked; tegulse ferruginous, im- punctate, white pubescent anteriorly; wings lightly and rather uniformly fuliginous, slightly paler apically, nervures piceous to black, basal nervure well beyond transverse median, the re- current nervures entering the second submarginal cell at about equal distances from base and apex; legs black, with long white pubescence, the tarsi tinged with red, the metatarsi very long and slender; spurs pale testaceous ; claws ferruginous, darker apically, deeply cleft, pulvilli distinct. Abdomen black, tinged with red basally, the basal segments almost impunctate, the apical segments finely punctured, seg- ment 6 quite closely so; pubescence pale on segments 1 and 2, short and fuscous on segments 3-5, long and fuscous on 6 and 7; segments 2-6 with apical fasciae of white pubescence, widely in- terrupted on 2 and 3, slightly so on 4, entire on 5 and 6; ventral segments 2-5 also with distinct entire white apical fasciae and with long white pubescence on the discs. Length 12 mm. Type: Male (Type No. 15710, Mus. Corn. 2001.); Austin, Texas (C. T. Brues, collector).
With the mandibles closed this would be easily mistaken for L. echinocacti Ckll., but with the labrum exposed it is easily dis- tinguished. This distinguishes this species at once from all the other North American species.
Megachile austinensis n. sp.
9 . Head broad, eyes subparallel; supraclypeal plate shin- ing, very sparsely punctured medially, closely so at sides and. above; clypeus almost impunctate in center, with a few widely scattered minute punctures, the surface polished, punctures coarse and quite close on extreme sides, apex entire, deeply im- pressed just before the edge which is slightly grooved; mandibles reddish above, black on the three inner teeth, with scattered, coarse, striate punctures above, 4-dentate, the two outer teeth broadly rounded, the third one acute and the inner one subacute; cheeks quite broad, finely and closely punctured, the punctures



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Psyche
rather shallow below, deeper above, pubescence quite thin and short, white; vertex quite finely punctate, the punctures well separated, surface finely tessellated between the punctures, pubescence long and thin, pale, with some short inconspicuous black hairs intermixed; lateral ocelli about equally distant from eyes and edge of vertex; front below ocelli well punctured, but the punctures not crowded; antennae apparently reddened (both are broken, only the stub of one flagellum left,); pubescence below anterior ocellus white and quite dense, clypeus nearly bare, with some inconspicuous yellowish hairs at sides. Thorax white pubescent except above, mesonotum with at least some dark pubescence (rubbed), and apparently also the scutellum; mesonotum rather dull, punctures quite small, close laterally and somewhat so anteriorly, sparse in center, the surface finely tessellated; scutellum with fine, widely separated punc- tures; pleura with crowded, rather fine punctures above, be- coming coarser below; propodeurn tessellate, with numerous fine and indistinct punctures, basal triangle granular; teguh dark ferruginous, minutely but fairly closely punctured; wings faintly infuscated, darker apically, nervures piceous to brownish, second recurrent nervure entering second submarginal cell slightly nearer apex than the first does to base; legs dark red, white pubescent, yellow on tarsi beneath, middle and hind meta- tarsi not quite as broad as their tibiae, the middle ones with rather long stiff whitish pubescence exteriorly, front metatarsi with a thin but long fringe posteriorly; spurs reddish-testaceous; claws reddish-testaceous basally, brighter red apically, with short and sharp basal setae, almost toothed.
Abdomen cordate, apical segments shining, punctures fine, quite close on basal segments, rather sparse on apical ones except the sixth; pubescence short and black, entirely white on segment 1 and white basally on segment 2; segments 1-5 with entire conspicuous apical white fasciae, narrow on segments 1 and 2, broader on 3-5; segments quite deeply impressed apically at sides, but slightly so medially; segment 6 quite broad, closely and finely punctured, slightly but distinctly concave at sides when viewed from above, straight in profile, with an obscure median longitudinal ridge on which the pubescence is black and



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19271 New Megachilid Bees 107
appressed and best seen in profile, on either side of this the the surface is covered with subappressed white pubescence, while the extreme tip is clothed with dense appressed fuscous pubes- cence, begment with erect black hairs across the base, conspicuous at sides; scopa yellowish-white, black on segment 6, and with a small tuft of black hairs at extreme sides of segment 5. Length 13 mm.
Type: Female (Type No. 15707, Mus. Comp. Zool.) ; Austin, Texas, May 8, 1901 (C. T. Brues, collector). Megachile wheeleri n. sp.
9 . Head broad, eyes subparallel, pubescence greyish-white on face, thin and white on cheeks, long and black or fuscous on vertex, extending down on cheeks for a short distance; supra- clypeal plate quite closely punctured, shining spaces between the punctures medially; clypeus with punctures close above and laterally, more separate in middle where the surface is shining, apex entire, smooth and -impunctate, thickened on the edge which is slightly grooved; mandibles broad, reddened apicdly, sparsely punctate above, 4-dentate, the three apical teeth sub- equal in size and rounded, the inner one acute, a slightly in- curved bevelled edge between the two inner teeth; cheeks about as broad as eye, shining, the punctures rather large but shallow, quite close, finer, closer and deeper above; vertex shining, nearly flat, with punctures well separated in general, close along edge behind ocelli; lateral ocelli slightly nearer edge of vertex than to nearest eye; front below ocelli densely punctured; antennae black above, obscurely reddened below, middle joint's but slightly longer than broad.
Thorax white pubescent at sides and behind, largely black on mesonotum and scutellum, whitish on mesonotum anteriorly and on scutellum posteriorly; mesonotum quite deeply and closely punctured, but the punctures well separated in center where the surface between them is shining; scutellum closely and finely punctate; pleura very closely and finely punctate above, the punctures larger and not so much crowded below; sternum with large, rather close punctures; propodeum with



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108 Psyche [April
minute indistinct punctures, closer posteriorly, surface rather shiny, basal triangle tessellate; tlegulee ferruginous, yellowish in front, rather closely punctured, t.he punctures small but distinct; wings subhyaline, clouded apically, nervures piceous to brownish, second recurrent nervure entering second submarginal cell slight- ly nearer apex than first does to base, but both rather distant; legs black, white pubescent, yellowish on tarsi beneath; middle metatarsi almost as broad as the tibiae, densely yellowish-white pubescent without; hind metatarsi almost as broad as the tibiae also; spurs pale yellow; claws pale ferruginous basally, some- what deeper red apically, basal teeth distinct. Abdomen ovoid, shining; segments 1 and 2 entirely white pubescent, and segment 3 narrowly white pubescent at base; segments 3-5 with rather long erect black pubescence on discs; segments 1-5 with dense, entire, white, apical fasciae, very broad on the apical segments, narrow on the first two; punctures fine, close on basal segments, very sparse on the fifth which is highly polished; segment 6 rounded apically and straight at the sides in dorsal view, straight in profile, shining, finely and rather closely punctured, with white appressed pubescence which is dense apically, thinning out basally, and with numerous long, erect, stiff black hairs; scopa white with a very faint yellowish tinge, black on segment 6 and on the apex of segment 5 medially. Length 12 mm.
Type: Female (Type No. 15708, Mus. Comp. Zool.) ; Alta Meadow, California, altitude 9000 ft., Aug. 23, 1917 (W. M. Wheeler, collector). Paratypes : 4 females, topotypical; 2 fe- males, Calgary, Alberta, Aug. 26, 1925 (Geo. Salt, collector). This is very close to M. chrysofhamni Ckll., but in the latter the punctures of the mesonotum are much closer and there are no blackhairs on the scutellum. The fifth abdominal segment is much more closely punctured also than in this species. Both of the species described here may be separated from chrysothamni by the following key :
1. Clypeus almost impunctate in the center, with very minute widely scattered punctures, but deeply punc- tate at sides. . . . . . . . . . . . .. . . . . . . . . . . . . . . . . austinensis Clypeus closely and strongly punctured throughout. . . .2.



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19271 New Megachilid Bees 109
2.
Pubescence of scutellum entirely light; punctures of me- sonotum very close throughout. . . . . . . . . . . chrysothamni Scutellum with some long black hairs; punctures of me- sonotum distinctly separated in center. . . . .. . .wheeleri Megachile inimica jacumbensis n. subsp.
3.
This resembles M. sayi Cress. except that the front tarsi are much shorter, the first joint being definitely shorter than the tibia and inclined to blackish along the anterior border; the lateral ocelli are about equally distant from the eyes and from each other; the clypeus has a quite definite though small median emargination; the legs except the front tarsi are black and the pubescence is white.
Type: Male (Type No. 15709, Mus. Comp. 2001.); Jacum- ba, California, Aug. 17, 1917 (Coll. W. M. Wheeler). Paratypes : 6 males, topotypical; 1 male, Warren, San Diego Co., California, Aug. 13, 1917.
This has been made a subspecies of inimica rather than of sayi because of the fact that inimica was described in 1872 (Trans. Am. Ent. Soc. Vol. 4), and sayi, which has been con- sidered the typical form, was not described until 1878 (Trans. Am. Ent. Soc. Vol. 7). In sayi s. str. the tarsal scale is much more produced above than in the form here described, and the scale at the anterior margin is fully as long as the tibia. There is also a tendency in sayi toward shortening the distance be- tween the lateral ocelli, this being usually somewhat shorter than the distance from the ocelli to the nearest eye or to the edge of the vertex, and the clypeus is not so definitely emarginate medially in the specimens which have been compared. Megachile spokanensis n. sp.
8. Head broad, eyes subparallel, pubescence entirely pale ochraceous, with no black hairs, nearly white on cheeks; clypeus closely and finely punctured, apex entire, completely covered with long dense pubescence; mandibles 3-dentate, the middle tooth small, outer margin rounded in the dorsal view, inferior



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110 Psyche [April
tooth very large, occupying about two-thirds of the inferior margin of the mandible, the outer margin of the tooth long, the inner margin from the apex of the tooth to the base of the man- dible much shorter, fringed with short yellowish pubescence, the apex being submedian with reference to the upper surface of the mandible; cheeks fairly broad, shining, finely punctured, the punctures close below, well separated above, lower angle with a rather small bare concavity, but with a robust tooth which is densely pubescent on the apex; vertex slightly rounded, closely and quite finely punctured, the punctures deep, pubes- cencelong and erect, much thinner than on face; lateral ocelli about equally distant from eyes and edge of vertex; antennae piceous above, somewhat paler below, rather short, the middle joints but slightly longer than broad, the apical one flattened and considerably dilated.
Thorax with pubescence entirely pale,
ochraceous above
fading to white below, quite long and dense on mesonotum, but not hiding the surface which is deeply and closely punctured throughout ; scutellum closely and rather more finely punctured pleura also finely and closely punctured; mesosternum concave, shining, almost impunctate, with two anterior, broad, trans- versely flattened spines which are rounded apically, one behind each front coxa; propodeum finely punctate, with long, rather dense pale pubescence; tegulse pale ferruginous, finely and rather closely punctured, pubescent anteriorly; wings subhyaline, clouded apically, nervures brownish, basal nervure slightly be- yond transverse median, second recurrent nervure entering .second submarginal cell nearer apex than first does to base. Legs black to piceous, pubescence white, pale yellowish on four posterior tarsi beneath; front cox% broad, bare, polished, with long, very broad and much flattened spatula-like spines, these incurved on inner apex, the apex narrowed and rounded, no red bristles on the coxse, the spines long white pubescent behind; anterior femora very strongly keeled, the posterior face being very wide, dark, rather closely and finely punctate, but nearly bare of pubescence, upper face also dark, the antero- inferior face polished testaceous, ferruginous basally and along upper margin; outer face of front tibiae dark, punctate and white



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front, the outer anterior margin with a&ortyellowish fringe, the inner one with a longer, more brownish fringe, the scale produced apically over the second joint, looking like the bow of a boat from without, the second joint narrowly produced apically, ex- tending slightly beyond the apex of joint 1, the third joint but very slightly dilated, the fourth not at all, fifth joint somewhat reddened apically, tarsal fringe white, rather yellowish within and tipped with fuscous or black, this evident at the edge of the fringe without; middle and hind lega entirely dark, the middle tarsi not much modified, with basal joint densely white pubescent exteriorly amd with a long white hair fringe, middle tibise with a bare impunctate area on outer face apically; hind tarsi rather peculiar, the basal joint short and thick, the following onea parallel-aided, hardly at all narrowed at baae or widened apicdly, outer surface strongly convex, the inner surface flat; spurs pale testaceous; claws reddish testaceous basally, piteous apically, rather deeply cleft on the four anterior legs, not so deeply on the hind legs.
Abdomen quite broad, pubescence pale ochraoeous, with no black hairs, segments 2-5 with dense apical fascisB of somewhat more whitish pubescence, punctures fine and close on basal seg- ments, more sparse on the apical segments, which are shining; segment 6 shining, rugose-punctate above the carina, neither emarginate nor produced medially, but the margin coarsely ir- regularly and rather sharply denticulate, a median rather deep concavity on the lower surface of the segment, rather coarsely rugoso-punctate on either side of thia, the apical margin with two large teeth, one on either side of the middle, these widely separated, sublateral in position, close to the incompicuous angles which represent the true lateral teeth; segment 7 large and cons- picuous, closely and finely punctured, rather evenly rounded, but the apex drawn out into a rather long slender spine; four ventral segments visible, these finely and closely punctured along their bases, the margins shining and impunctate, the fourth segment



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112 Psyche [April
broadly membraneous and transparent on the apical margin. Length 11 mm.
Type: Male (Type No. 15717, Mus. Comp. 2001.); Little Spokane, W. T., Washington Territory July 26, 1882 (Samuel Henshaw, collector). Paratypes: 1 male, Camp Umatilla, W. T. (across the Columbia River from Umatilla, Ore.), June 26, 1882; 2 males, Alta Meadow, California, altitude 9000 ft., Aug. 23, 1917 (W. M. Wheeler, collector).
This is quite near M. manifesto Cress. but in the latter species there are no spines on the mesosternum, the apical spine of segment 7 is much longer, and the hind tarsi are more nearly normal. The inferior mandibular teeth, the front tarsi, and the carina of segment 6 are almost exactly alike in the two species. It is quite possible that this is the male of M. wheeleri, since two of these males were caught in the type locality of that species. Megachile pseudonigra n. sp.
9 . Head broad, eyes parallel, pubescence fuscous, hardly black; supraclypeal plate finely punctured, somewhat sparsely so in center; clypeus very finely and closely punctured above, sparsely and more coarsely so on apical two-thirds, apex entire, with a raised or thickened impunctate edge; mandibles broad, black, \obscurely reddish apically, with a very few scattered punctures above, doubly punctate on outer face at base, dis- tinctly 4-dentate, the two apical teeth truncate, the third and fourth acute, a bevelled cutting edge between the latter; cheeks fairly broad, closely punctured above and below, shining above; vertex slightly rounded, punctures close medially, rather widely separated laterally; lateral ocelli about equally distant from eyes and edge of vertex; front below ocelli densely and finely punc- tured; antennae black above, obscurely reddish below, middle joints but slightly longer than broad.
Thorax with fuscous pubescence, apparently blacker on sur- face of mesonotum (specimen somewhat rubbed) ; mesonotum sparsely punctate medially, closely so laterally and behind, the surface finely tessellated; scutellum closely and finely punctate, and the pleura very finely and closely punctate above, more



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19271 New Megachilid Bees 113
coarsely so below; propodeurn with numerous fine indistinct punctures, tessellate, the basal triangle tessellate or granular; tegulse bronze-piceous, minutely punctured; wings subhyaline, faintly clouded apically, nervures brownish-testaceous, basal ner- vure beyond transverse median, second recurrent nervure en- tering second submarginal cell nearer apex than the first does to base; legs black, pubescence fuscous, tinged with red beneath tarsi and on middle metatarsi without, black on the outer faces of the tibiae, middle and hind metatarsi fully as broad as their tibiae; spurs yellowish-brown; claws reddish-testaceous basally, darker apically, with indistinct basal teeth. Abdomen cordate-ovoid, shining, finely punctate, closely so on basal segments, sparsely so on the apical ones except the sixth, pubescence black, entirely fuscous on segment 1, and segments 2-5 with inconspicuous apical fuscous fascise; segment 6 very slightly, if at all, concave at sides in the dorsal view, straight in profile, shining, finely and rather closely punctured, with sub- appressed fuscous pubescence and numerous erect black hairs; scopa fuscous, shorter and deeper black on segment 6. Length 10.5 mm.
Type: Female (Type No. 15718, Mus. Comp. Zool.) ; Uma- tilla, Oregon, June 24, 1882 (Samuel Henshaw, collector). This would appear to be near M. vandykei Ckll., but in that species the pubescence is entirely black, and the clypeus is des- cribed as being "densely rugoso-punctate, with a polished shining spot at middle of upper edge, and a median band in which the surface is shining between the punctures, lower margin thick- ened, slightly emarginate in middle." The clypeus in this species does not answer to that description at all, and the pubescence is fuscous rather than black, with definite though inconspicuous fuscous fasciae. It may be possible that this is a melanistic form of some light haired species.
Megachile mendica snowi n. subsp.
9. Head with eyes slightly converging below; supra- clypeal plate shining, sparsely punctate medially; clypeus close- ly and rather coarsely punctured in general, but with the punc- tures well separated in the center, apical margin entire, the edge



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114 Psyche [April
thickened and slightly grooved; mandibles black, broad, with a few scattered punctures above, 4-dentate, but the margin be- tween the two inner teeth with a slight angular protuberance, approaching the 5-dentate condition; cheeks quite narrow and quite closely punctured, with short, rather dense, white pubes- cence; vertex very slightly rounded, the punctures distinct and well separated, surface shining between the punctures, pubes- cence black, erect, and quite long; lateral ocelli about equally distant from eyes and edge of vertex; front below ocelli densely punctate; antennae piceous below, somewhat darker above, length of middle joints about one and a half times their breadth; pubescence of face below anterior ocellus white, slightly mixed with black above antennae, very thin on clypeus. Thorax with pubescence largely white, but mostly black on mesonotum posteriorly, mixed with whit-e in the middle, and largely replaced by white anteriorly, with some shorter whitish pubescence in the scutello-mesothoracic suture, but this not conspicuous; mesonotum with punctures quite close, more or less separated in center, the surface between them tessellate; scutellum closely punctured, the punctures separated medially, with long black hairs and shorter, softer, white pubescence; pleura with punctures fine and crowded above, larger and dis- tinctly separated below; propodeum tessellate, the punctures very fine and indistinct, basal triangle tessellate below, granular or subrugose above; tegulae piceous, obscurely testaceous an- teriorly, with fine shallow punctures; wings subhyaline, faintly clouded apically, nervures yellowish-ferruginous, second recur- rent nervure entering second submarginal cell very near the apex, the first rather far from base; legs piceous to dark red, white pubescent, yellow on tarsi beneath; middle tarsi slightly narrower than the tibiae, densely pale pubescent without, the following joints but slightly narrowed; hind metatarsi slightly narrower than the tibiae; spurs pale yellow; claws with distinct basal teeth, darker apically, pale basally. Abdomen cordate, short black pubescent, but the pubescence entirely white on segments 1 and 2, and segments 2-5 with white apical fasciae, these entire but rather narrow; segment 6 slightly concave at sides viewed from above, the apex rather evenly



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19271 New Megachilid Bees 115
rounded, slightly concave in profile also, but so slightly as to be hardly noticeable, with no erect hairs visible in profile, finely and closely punctured, pubescence appressed, yellowish-white, more or less reddened medially to apex, hiding the surface on apical half, thin basally, with scattered inconspicuous erect black hairs at sides; scopa entirely yellow, but with a few lateral dark hairs on segment 6. Length 13 mm.
Type: Female (Type No. 15719, Mus. Comp. Zool.); Oak Creek Canyon, Arizona, 6000 ft. altitude, Aug. (F. R. Snow, collector). Paratype : 1 female, topotypical. In mendica s. str. the pubescence of segment 2 is black on the