Synonyms and other taxonomic changes
Coccinella transversoguttata Mulsant
Explanation of Names
transversoguttata (L). "across" + "spotted"
Head black with two white spots (white spots faded in spmns)
Pronotum black with white marking on each side
Elytra with solid black band or band of black spots behind pronotum, two elongated or teardrop-shaped black markings on each side
- per Lost Ladybug Proj. spotter data
- Worldwide in Northern Hemisphere; in North America: CA-VA-Labrador to AK, plus Greenland(!) (1)
Based on Lost Ladybug Project and BugGuide records, the species is now most frequently found in the Rocky Mountains.
mostly: May-Sept (BG data)
Numbers of this species are declining throughout its range, perhaps due to competition from introduced species such as the Seven-Spotted Lady Beetle (Coccinella septempunctata) and Multicolored Asian Lady Beetle (Harmonia axyridis):
"This was certainly the most abundant, widespread ladybug in Alberta up until the arrival of the seven-spot....[T]he relative abundance (among the aphid-eating ladybugs other than the seven-spot) of transverse ladybugs declined steeply during the decade after the seven-spot's arrival." (John Acorn, Ladybugs of Alberta
, p. 135.)(2)
Ladybugs of Alberta also cites studies conducted in Maine, Manitoba, and South Dakota that found similar declines in Transverse Lady Beetle populations after the introduction of Seven-Spotted and Multicolored Asian Lady Beetles; see chapter 4, "Introduced Ladybugs and Conservation."
considered by New York State to be a "Species of Greatest Conservation Need" (SGCN) (3)
Three-banded Lady Beetle, Coccinella trifasciata - Front of pronotum usually with white border; head of male and some females with white center; usually with wide black bands instead of narrow teardrop-shaped spots on sides.
Coccinella monticola, Coccinella fulgida - Single large black spot behind pronotum, not narrow band; markings on sides often larger.
Some species of Hippodamia have similar markings on elytra, but shape elongated, tapered, not rounded; pronotum often with white border and/or more than two white markings; legs long and always visible from above.
Gordon, 1985, especially pp. 790-793, figures 641-642.(1)
Acorn, "Ladybugs of Alberta," especially pp. 49-51 (conservation), pp. 135-136 (identification).
Harrison, W.C., and J. Acorn. 2000. The effects of the introduced lady beetle, Coccinella septempunctata, on the native coccinelline fauna of Alberta. Proc. Entomol. Soc. Alta. 48: 6.
Mulsant, M.E. 1850. Species de Coleopteres trimeres securipalpes. Annales des Sciences Physiques et Naturelles d'Agriculture et d'Industrie 2: 1-1104. (p. 117