Extracted from THE POLLEN-COLLECTING BEES OF THE ANTHIDIINI OF CALIFORNIA (Hymenoptera: Megachilidae) by GRIGARICK A., A. (1968).
Megachile emarginata Say, 1824. In Keating, Nam Long's
2nd Exped., 2:352 1825, appendix, 83. Type 9, Missouri
(type lost). Anthidium atrifrons Cresson, 1868. Trans. Amer. Ent. Soc.,
1:387. 4 9 Syntypes, New Mexico, Colorado (ANSP). Anthidium atriventre Cresson, 1878. Trans. Amer. Ent. Soc,
7:111. Holotype 9, California (ANSP). NEW SYNONYMY. Anthidium saxorum Cockerell, 1904. Bull. South. Calif. Acad.
Sci. 3:72. Holotype $, "re" (Rock Creek, California)
(AMNH). NEW SYNONYMY. Anthidium collectum ultrapictum Cockerell, 1904. Bull. South.
Calif. Acad. Sci., 3:73. Holotype $, Tehachapi, California
(AMNH). NEW SYNONYMY. Anthidium titusi Cockerell, 1904. Bull. South. Calif. Acad.
Sci., 3:73. Holotype $, Fort Collins, Colorado (AMNH).
Anthidium bernardinum aridum Cockerell, 1904. Bull. South.
Calif. Acad. Set., 3:76. Holotype $, "re" (Rock Creek,
California) (AMNH). NEW SYNONYMY. Anthidium astragali Swenk, 1914. Nebr. Univ. Studies, 14:16;
6, 9. Holotype £, Sioux Co., Nebraska (UN). NEW
Anthidium fresnoense Cockerell, 1925. Proc. Calif. Acad. Sci.,
Series 4, 14:347. Holotype 9, Huntington Lake, Fresno Co.,
California (CAS). NEW SYNONYMY. Anthidium angulatum Cockerell, 1925. Proc. Calif. Acad. Sci.,
Series 4, 14:357. Holotype $, Huntington Lake, Fresno
Co., California (CAS). NEW SYNONYMY. Anthidium hamatum Cockerell, 1925. Proc. Calif. Acad. Sci.,
Series 4, 14:358. Holotype $, Mt Timpanogos, Utah
(CAS). NEW SYNONYMY. Anthidium spinosum Cockerell, 1925. Proc. Calif. Acad. Sci.,
Series 4, 14:359. Holotype $, Fallen Leaf Lake, California
(CAS). NEW SYNONYMY. Anthidium lucidum Cockerell, 1925. Proc. Calif. Acad. Sci.,
Series 4, 14:361. Holotype <$, Huntington Lake, Fresno
Co., California (CAS). NEW SYNONYMY. Anthidium rhodophorum Cockerell, 1925. Ann. Mag. Nat. Hist.,
Series 9, 16:623. Holotype 9, Colorado (AMNH). NEW
Anthidium sculleni Schwarz, 1930. Jour. New York Ent Soc., 38:10. Holotype <$, Wallowa Lake, Oregon (OSU). NEW SYNONYMY.
Biology.—Hicks, 1926a, Colo. Univ. Studies, 15:247.
CALIFORNIA INSECT SURVEY
CwtMM d tlll»lll|, (M MlMlHtofl UNIVMSITV 0» CAIIFORHIA
Map 13. California distribution of Anthidium emarginatum
Geographic range.—British Columbia, Nebraska, and Kansas, west to Washington and California.
California records.—ALPINE CO.: Hope Valley, 1 9, VII-18-48 (P. Hurd, CIS). Kinney Reservoir, 1 £, VI-8-60 (O. Stage, CIS). Silver Creek, 2 2, VII-13-48 (R. Bohart, CIS). DEL NORTE Co.: Little Grayback Pass, 1 i, VII-9-58 (J. Powell, CIS). EL DORADO Co.: Echo Lake, 1 9, VI-21-61 (W. MiddlekaufT, UCR). Fallen Leaf Lake, 1 o, VI-ll-15 (E. Van Dyke, CAS). FRESNO Co.: Huntington Lake, 2 $ , 3 9, VII-1917, on Phacetia (I. McCracken, CIS). INYO Co.: Big Pine, 1 9, VI-23-37 (E. Van Dyke, CAS). Lone Pine, 10 6,2 9, VI-S-37, on Astragalus Bolanderi (C. Michener, UCR). Mammoth, 1 9, VII-1933 (E. Linsley, UCR). Mazourka Canyon, Inyo Mts., 1 $, VI-1-37, on Phacelia (C, Michener, UCR). Westgard Pass, 1 £, V-17-37, on Dalea Fremontii (C. Michener, UCR). Wyman Canyon, White Mts., 4 9, VI-21-61 (J, Buckett, LACM); 3 9, VI-27-61, on Penstemon (J. Powell, CIS). KERN Co.: Mill Potrero, 16 o, 6 9, VII-8-59 (R. Bohart, P. Marsh, A. Menke, UCD). Seartes Station, 1 S, V-25-49 (E. Linsley, CIS). LASSEN Co.: Hallelujah Junction, 1 2, VI-28-62 (M. Irwin, UCD). Snag Lake, 1 2, VII-5-57 (R. Schoep-pner, UCD). Los ANGELES Co.: Big Pine Camp, IS d, 13 2, VII-17-27, on Phacelia heterophylla, Phacelia ramosisst'ma, Lotus argyracus ssp. multicaulis, Erigeron toliosus var. sreno-phyllus (P. Timbertake, UCR). Camp Baldy, 1 9, VI-26-50 (H. Hansen, CIS). Crystal Lake, 1 9, VI-29-50, on Eriodic-tyon (P. Hurd, CIS). MODOC Co.: Cedar Pass, 1 9, VI-29-58 (R. Browning, UCD). MONO Co.: Blanco's Corral, Whilo Mts., 1 S, 4 9, VII-7-53 CJ. MacSwain, CIS). Crooked Creek, White Mts., 5 3,1 9, VI-23-61 (J. Powell, CIS). Elory Creek, 1 6 , VII-31-58 (J. Jesson, UCD). June Lake, 1 o, VI-30^19 (H. Cott, UCD). Monitor Pass, 4 mi. E, 1 $, VI-24-62 (J. Powell, CIS). McKay Creek, Sonora Pass, 1 3,2 9, VIII-18-60 (C. Toschi, CIS). Poison Creek, White Mts., 1 9, VI-26-61 (D. Miller, UCD). Rock Creek, 1 9, VI-23-57, on Phacelia (C. Michener, UCR). Sonora Pass, 7 9, VIII-IO-60 (M. Irwin, UCD). Walker Lake, 1 3, VII-23-05 (CIS). NEVADA CO.: Sa^chcii Creek, near Hobart Mills, 1 3, VII-5-62 (J. Powell, CIS). PLUMAS CO.: Quincy, 4 mi. W, 3 3,7 9, VI-26^19 (R. Bechtel, CIS). RIVERSIDE CO.: Idyllwilcl, 1 $, 1 9, VII-3-30, on Phacelia calilornica (P. Timbcrlake, UCR). SAN BENITO Co.:Idria, 1 o", VI-29-55, on Phacelia (P. Hurd, CIS). SAN BERNARDINO CO.: Big Bear Lake, 1 £, VII-4-34 (I. McCracken, CAS). Big Pines, 1 6 , VI—16—25, on Phacelia heterophylla (P. Timber-lake, UCR); 1 9, VII-12-37, on Phacelia ramosissima (P. Timberlake, UCR). Camp Baldy, 2 5,3 2, VI-30-56 (L. Stange, LACM). Cajon Pass, 2 mi. W, 1 9, VI-7-58 (E. Schlinger, UCD). Forest Home, 1 9, VII-5-36, on Cryptantha intermedia (P. Timberlake, UCR). Wrightwood,
1 6\ VI-14-59 (J. Hall, UCD). SANTA BARBARA Co.:
Carpinteria, 1 3, VII-21-37 (B. White, CAS). SISKIYOU Co.:
Mt. Shasta, 1 9, VIII-1-50 (LACM). Lava Beds Nat'l Mon.,
2 9, VIII-6-63, on Phacelia (J. Schuh, JS). TRINITY Co.:
Big Flat, Coffee Creek, 1 9, VI-21-34 (T. Aitken, UCR).
Coffee Creek, 10 mi. N, 1 o , VII—15—55. on Symphoricarpos
(J. MacSwain, CIS). TULARE Co.: Mineral King, 1 2, VIII-
4—22 (C. Fox, CAS). TUOLLMNE CO.: Blue Canyon, Sonora
Pass, 3 6,1 9, VIII-18-60 (A. Menke, UCD). Sonora Pass,
1 9, VII-11-51 (J. MacSwain, CIS).
A. emarginatum is one of the most difficult species to distinguish in California since it presents a con¬siderable amount of variation. The seta! brush of the
males varies in color from nearly all black to reddish-black. However, the presence of a well-developed lateral and median lobe on sternum VI (fig. 35) to¬gether with the lateral lobe of tergum VII (fig. 34 mean width subequal to distance from center spine) will serve to separate the males from all other species except dammersi and mormonum. The median lobe of sternum VI is much narrower than in mormonum and not parallel-sided as in dammersi. In addition, the setal brush of emarginatum is always darker than in mormonum.
The females of emarginatum, tenuifiorae, and dam¬mersi also pose problems in recognition. The convex clypeus of emarginatum (fig. 95) separates it from the rather flat clypeus of tenuifiorae (fig. 96), and the convex tergum VI of emarginatum differs from the relatively straight one of dammersi. The key utilizes color, and emarginatum is conspicuously vari¬able in this regard. To overcome the difficulty, emarginatum is keyed out twice. This is necessary since emarginatum in southern California has much larger pale maculations including a nearly all yellow clypeus as opposed to the dark clypeus in northern California. In addition, the southern California popu¬lations are bright yellow in contrast to the paler northern California populations. The color patterns of the two extremes are conspicuously different when compared; however, since sufficient intergraclation in intermediate localities (Inyo Co.) exists, division into subspecies does not appear to be warranted. This increase of maculation in southern California is found in several other species, such as in fenui-fiorac and atripes, although not as extreme.
A. emarginatum is a fairly common species as indi¬cated by widespread records of 148 males and 156 females. The species prefers montane environments and is found in nearly all the major mountain ranges of California except the north-central part of the Coast Range.
A. emarginatum has been recorded visiting plants in six families but was most frequently collected on Phacelia in the Hydrophyllaceae. Hicks (1926a) ob¬served a female of emarginatum collecting down from stems of Cirsium undulatum in Colorado. Down nests and larvae collected by E. Jaycox are shown in figure 214. The only record of parasitism of emarginatum was by Leucospis affinis Say according to Graenicher (1906).