Extracted from: Roberts, 1973. Bees of Northwester America: AGAPOSTEMON. Agricultural Experimental Station. Oregon State University.
Diagnosis. The male of this species has a bright metallic green head and thorax; the metasoma is black and yellow banded, with metallic tints apically. The male of A. angelicus may be distinguished from males of A. coloradinus and A. virescens by the presence of yellow on its last two visible sterna (fifth and sixth), from males of A. melliventris by the presence of an apical black stripe on the posterior surface of its hind tibia (Figs. 4, 6), and from males of A. texanus and A. femoratus by the lack of a medial brown or black stripe on the anterior surface of its hind tibia (Figs. 3-5). Agapostemon texanus may lack the anterior tibial stripe, but such specimens also lack the posterior stripe present in A. angelicus.
The female of A. angelicus has a bright metallic green head, thorax, and metasoma. It may be distinguished from females of most other species by the presence of two sizes of punctures on its scutum (Figs. 14-15). The females of A. texanus are similarly colored and also have two sizes of scutal punctures. Thus, females of A. texanus and A. angelicus cannot be distinguished by morphological features.
Distribution. Although common only in the and regions of the
southwestern United States and northern Mexico, males of A. angelica:
have been found as far north as west-central North Dakota, as far south as northern Durango (Mexico), as far east as central Iowa, and as far west as southwestern California (Fig. 18).
Distribution. Although common only in the and regions of the
southwestern United States and northern Mexico, males of A. angelica:
have been found as far north as west-central North Dakota, as far south as northern Durango (Mexico), as far east as central Iowa, and as far west as southwestern California (Fig. 18).
In the Northwest A. angelicus has been collected only in northern
Utah, southeastern Oregon, and in the Snake River Valley of Idaho. It
may also occur in northern Nevada.
In the Northwest A. angelicus has been collected only in northern
Utah, southeastern Oregon, and in the Snake River Valley of Idaho. It
may also occur in northern Nevada. This species ranges from below sea level in Death Valley, California, to 12,000 feet (3,658 m) on Mt. Evans, Colorado, where timberline is 11,700 feet. The recorded altitudinal range of this species surpasses that of almost all other North American bees. In the southern portion of its range (Arizona) males of this species have been collected from April through November. Further north in Kansas males of A. angelicus have been collected from June through October.
Biology. Little is known of the biology of this species, but it is probably similar to the biology of its close relative, A. texanus. Agapostemon angelicus has been observed (Linslev, 1962) sleeping on the dried flower heads of a clump of Heterotheca suhaxillaris (Compositae) in southeastern Arizona. Numerous males and occasional females were seen on these plants on 26 of 28 consecutive nights. The females always slept alone, but the males tolerated each other's presence and as many as six could be seen crowded onto one flower head. Grasping the plant with their legs, the males slept with their bodies extended, wings folded, and antennae held forward and pressed together or only slightly divergent. The author has observed the males of this species sleeping atop sunflowers (Helianthus sp.) in a pasture in eastern Colorado, in a manner similar to that noted by Linsley (1962). Both flowers and hers were covered with a heavy dew. As the morning was cold, the bees did not dry off and fly until about nine o'clock. This species, like most bees, normally forages from about 9 a.m. to noon when the weather is warm and sunny. However, it is obvious that the females are able to adapt their foraging period to the availability of a locally abundant pollen source. Agapostemon angelicus females have been reported (Linslev and Hurd, 1959) gathering pollen from the afternoon-flowering Rientzelia pumila (Loasaceae) at sunset (5:40 p.m. ). The same species has been reported (Linslev, 1960) collecting pollen from the matinal flowering Curcurbita foetidissima at 5:35 a.m. when the
Distribution. Although common only in the and regions of the
southwestern United States and northern Mexico, males of A. angelica:
have been found as far north as west-central North Dakota, as far south as northern Durango (Mexico), as far east as central Iowa, and as far west as southwestern California (Fig. 18). In the Northwest A. angelicus has been collected only in northern Utah, southeastern Oregon, and in the Snake River Valley of Idaho. It may also occur in northern Nevada.
This species ranges from below sea level in Death Valley, California, to 12,000 feet (3,658 m) on Mt. Evans, Colorado, where timberline is 11,700 feet. The recorded altitudinal range of this species surpasses that of almost all other North American bees.
In the southern portion of its range (Arizona) males of this species have been collected from April through November. Further north in Kansas males of A. angelicus have been collected from June through
October. Air temperature was 52-54 F (11.1-12.2 C) and a heavy overcast was threatening rain.
Extracted from: Roberts, 1972. The University of Kansas Science Bulletin.
Agapostemon angelicus Cockerell 1924. Type 9, California Academy of Sciences.
I have seen the type in San Francisco and it is from Pond Island Bay, Angel de la Guarda Island in the Gulf of California, Mexico. As the males of A. texanus are rare relative to those of A. angelicus in this region, it seems reasonable and expedient to consider this type to be conspecific with those males which differ in genitalia and color pattern from those of A. texanus.
Distribution. All males of A. angelicus have been found well within
the range of the males of A. texanus. Owing to this sympatry and my
inability to distinguish between females of A. texanus and A. angelicus, I have here considered the distribution of males and disregarded females.
Although common only in the arid regions of the southwestern United
States and northern Mexico, males of A. angelicus have been found as far north as west-central North Dakota, as far south as northern Durango (Mexico), as far east as central Iowa, and as far west as southwestern California. This species ranges from below sea level in Death Valley, California, to 12,000 ft. (3,658 m) on Mount Evans (timberline is at 11,700 ft.) in Colorado. The altitudinal range of A. angelicas is as astounding as the latitudinal range of A. texanus. In Arizona males of A. angelicas have been collected from April through November; in Kansas from June through October; and in Mexico from June through October. (Map, Fig. 20.)
Albeit uncommon, A. angelicas does occur in the Great Plains, where
it is found together with A. texanus in the gallery forests of the tributaries of the Missouri and Mississippi Rivers. This habitat is the "Northern Floodplain Forest" of Popalas, Salix, and Ulmas (no. 98 in Appendix A). While not as diverse as those of A. texanus, its habitats are numerous (39 of the 116 given by A. W. Kiichler 1964 cf. Appendix A).
Diagnosis. The male may be distinguished from many other species by
its toothed hind femora, the apical stylus on its gonostylus, and the lack of a low medial ridge on the apical half of its last visible sternum; and from A. texanus by the shorter apical stylus with swollen base and enlarged apex on its gonostylus, and by the presence of a posterior stripe and absence of an anterior stripe on its hind tibia. The female may be distinguished from most other species by its bright metallic green to blue metasomal terga, its almost hyaline wings, and by the presence of two distinct sizes of mesoscutal punctures. I have labeled females of A. angelicas as "Agapostemon texanus or A. angelicus" because I am unable to separate them from A. texanus.
Sandhouse (1936) claimed that these species differ in the punctation of the mesoscutum and in the color of the pubescence. After having examined many thousands of females of these species I am forced to conclude that the variation within A. texanus nearly encompasses the range of variation within A. angelicus, thus invalidating the characters used by Sandhouse. It is probably true that the modes of A. angelicus characters differ from those of A. texanus but this cannot be demonstrated without positively identified females of both species. If one were able to positively identify A. angelicus females, perhaps by means of rearing, it might be possible to utilize a discriminant function to distinguish between females of the two species. Owing to the occurrence of A. texanus males within the range of A. angelicus males, I was unable to obtain females which were indisputably A. angelicus. Even if one were to find an area where only A. angelicus
occurred, one could not be sure that differences between these females and females of A. texanus were not simply geographic variations.
Variation. Basing the probable identity of females on the relative
abundance of males, it would seem that most females of A. angelicus have a slightly shinier mesoscutum and whiter pubescence than most of those of A. texanus. Like the males, the females of A. angelicus probably average slightly smaller than those of A. texanus, but the variation within each species is far greater than any difference between them. In both males and females of A. angelicus the metallic coloration is the same green as that of the sympatric A. texanus. The most noticeably variable character of A. angelicus is the amount of melanic pigmentation on the fore coxae of males, which range in color from yellow to brown-black, but intra-locality variation is far greater than inter-locality variation.
Description male (Figs. 73-74, 164, 181)
Males as in A. texanus but only about 85% as large with whiter
pubescence on the mesonotum and metanotum; with dark stripe present
posteriorly and absent anteriorly on its hind tibia (Fig. 164) ; with apical stylus on its gonostylus shorter, swollen basally, and larger apically; with medial plate on its gonostylus smaller; and with basal stylus on its gonostylus broader and blunt apically (Fig. 181).
female (Figs. 67-68)
As in A. texanus but always green and probably smaller with shinier
mesoscutum and whiter pubescence.
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