Species Details

Bombus insularis

University of Alberta E.H. Strickland Entomological Museum Read more about this collection »

SeasonalityQueens may be seen flying from late March to late October; males from late April to late September (Thorp et al. 1983). IdentificationBombus insularis belongs to the subgenus Psithyrus which was historically treated as a separate genus from the rest of the Bombus due to its parasitic lifestyle (Alford 1975). Michener (2000) considers all species formerly treated as Psithyrus to be Bombus. Psithyrusis a parasitic subgenus, and all species lack a worker caste, cannot produce wax, have a stronger exoskeleton, and have no pollen baskets (Alford 1975). Psithyrus males can be distinguished by an almost straight penis valve shaped like an arrow head; the hind tibia of Psithyrus queens is convex with a hairy outer surface (Williams 2008). Bombus insularis queens have yellow pile covering the mesopleura to the base of legs, dark venter, fourth antennal segments that are much shorter than the third or the fifth, and moderately stained wings (Franklin 1912). Bombus insularis can be distinguished from the closely related Bombus fernaldae by the presence of yellow hair between the antennal bases (Thorp et al. 1983). Queens vary in length from 13.5 mm to 18 mm; in wingspan from 32 mm to 38 mm; and in width of second abdominal segment from 7 mm to 9 mm (Franklin 1912).

Scientific Name Bombus insularis Habitat Found in a wide range of habitats due to its parasitic lifestyle (Alford 1975). Seasonality Queens may be seen flying from late March to late October; males from late April to late September (Thorp et al. 1983). Identification
Bombus insularis belongs to the subgenus Psithyrus which was historically treated as a separate genus from the rest of the Bombus due to its parasitic lifestyle (Alford 1975). Michener (2000) considers all species…
Bombus insularis belongs to the subgenus Psithyrus which was historically treated as a separate genus from the rest of the Bombus due to its parasitic lifestyle (Alford 1975). Michener (2000) considers all species formerly treated as Psithyrus to be Bombus. Psithyrusis a parasitic subgenus, and all species lack a worker caste, cannot produce wax, have a stronger exoskeleton, and have no pollen baskets (Alford 1975). Psithyrus males can be distinguished by an almost straight penis valve shaped like an arrow head; the hind tibia of Psithyrus queens is convex with a hairy outer surface (Williams 2008). Bombus insularis queens have yellow pile covering the mesopleura to the base of legs, dark venter, fourth antennal segments that are much shorter than the third or the fifth, and moderately stained wings (Franklin 1912). Bombus insularis can be distinguished from the closely related Bombus fernaldae by the presence of yellow hair between the antennal bases (Thorp et al. 1983). Queens vary in length from 13.5 mm to 18 mm; in wingspan from 32 mm to 38 mm; and in width of second abdominal segment from 7 mm to 9 mm (Franklin 1912).
Life History
Bombus insularis is a cleptoparasite of the nests of other Bombus species. Bombus insularis parasitizes at least 6 other Bombus subgenera (Thorp et al. 1983), an unusually large host range for the Psithyrus subgenus…
Bombus insularis is a cleptoparasite of the nests of other Bombus species. Bombus insularis parasitizes at least 6 other Bombus subgenera (Thorp et al. 1983), an unusually large host range for the Psithyrus subgenus which normally specializes in a single subgenus (Alford 1975). Alford (1975) reviews the life history of B. insularis. Queens of B. insularis emerge later in spring than other Bombus queens and forage on pollen and nectar until a suitable nest to invade is found. Mature nests that were founded earlier in the year appear to be preferred, although entrance to the colony is normally easier if the colony is smaller. The queen enters the nest and will remain motionless with legs drawn in close if she is attacked. Upona successful entrance, the queen will hide for a short time, presumably to acquire the odor of the colony to avoid further attacks by workers. Sometimes B. insularis queens will kill the host queens, but often they are able to cohabitate. She will then construct her own egg cells and quickly lay eggs, sometimes feeding on the host brood. Her eggs and larva are reared by the host workers alongside the host brood. The newly emerged queens and males will immediately leave the nest to acquire mates. The B. insularis queen will then leave and seek out other nests to parasitize.
Conservation Unknown. Diet Info Bombus insularis were observed foraging on 16 plant families with 30 genera in California. The predominant families fed upon were Compositae, Rosaceae, Ericaceae, and Polygonaceae (Thorp et al. 1983). Range Western and eastern neartic regions (Williams 1998).
Bombus insularis
Bombus insularis

Citation

Page Citation for Bombus insularis

Page Citation

"Species Details - Bombus insularis, University of Alberta E.H. Strickland Entomological Museum." University of Alberta Museums Search Site, https://search.museums.ualberta.ca/g/2-38255. Accessed 29 Mar. 2024.

Authorship

Name Vandervalk, L.
Role species page author
Date 2011

References

Specimen Information

There are 24 specimens of this Species.

24 results plotted on map in 15 markers.
Note: Only records with latitude and longitude coordinates are plotted on map.

UASM327717 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Beaverlodge Collected ByKlassen, W. Date Collected1956-07-02

UASM327718 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Beaverlodge Collected ByKlassen, W. Date Collected1956-06-13

UASM327719 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, George Lake Date Collected1965-06-22

UASM327720 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, George Lake Date Collected1965-07-28

UASM327721 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Abee Collected ByHoreczko, N. Date Collected1957-05-17

UASM327722 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Menaik Collected ByHocking, B. Date Collected1954-07-26

UASM327723 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Ponoka Collected ByHocking, B. Date Collected1954-07-24

UASM327724 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Thunder Lake Collected ByBuerger, G. Date Collected1965-06-20

UASM327725 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Gorge Creek Collected ByHochachka, P. W. Date Collected1958-06-02

UASM213720 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2012-08-04

UASM213939 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-08-09

UASM213940 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-08-30

UASM213953 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-05-26

UASM213954 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-05-29

UASM213955 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Saskatchewan, Killaly Collected ByAnweiler, G. G. Date Collected2013-06-17

UASM340401 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Tawatinaw Collected ByAnweiler, G. G. Date Collected2013-09-05

UASM340402 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Saskatchewan, Crooked Lake, Melville Beach Collected ByAnweiler, G. G. Date Collected2013-06-18

UASM340403 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-05-30

UASM340404 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-07-19

UASM340405 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-07-21

UASM340455 - Bombus insularis

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByAnweiler, G. G. Date Collected2013-06-01

Adult Seasonal Distribution