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 A
Graphic Guide for Identification of Adult European Craneflies;
Tipula
paludosa and T.
oleracea (Diptera:Tipulidae)
Eric LaGasa,
Washington State Department of Agriculture
The cranefly known as the
European cranefly in the
Pacific Northwest, Tipula
paludosa Meigan, is
an introduced exotic pest first found in the region in 1965
in British Columbia, Canada. Since then, it has gradually
spread into Washington State and parts of Western Oregon and
has become the most serious economic pest of lawns, pastures
and hayfields in the northwest.
In 1998, a second, closely
related cranefly species from Europe was found in the Pacific
Northwest. The new species, Tipula
oleracea L.,
is almost identical in appearance to T.
paludosa and similar biologically.
It is also considered a serious pest of turf and other plants
in its native Europe. However, T.
oleracea can complete two
generations per year (European cranefly has one) and adult T.
oleracea emerge in the
spring as well as the fall, when most European craneflies emerge.
Between 1998 and 1999, Tipula
oleracea was found in a
few locations in Western British Columbia, Western Washington,
and Western Oregon, but the extent of the currently infested
area is not known. The following graphics and information have
been developed by the Washington State Department of Agriculture
(WSDA) to help future efforts to delimit the distribution of
T. oleracea
in North America. |
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As
mentioned above, Tipula
paludosa and
T. oleracea
are extremely similar species, but they may be separated by
the characters presented below. In general appearance,
they are large craneflies with grayish-brown bodies.
Male craneflies may have a wingspan from 1¼ to 1½ inches.
Females are larger, with a wingspan of 1½ to 2 inches.
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wings are slightly cloudy, with a darker area and a white stripe
along the leading edge - visible in the following pictures against
dark and light backgrounds. Other than the leading edge
stripes, there are no pigmented areas on the veins or cross-veins
and no other spots or "pictures" in the wings. |
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Figure
4. T.
oleracea
wing, white background.
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Figure
5. T.
oleracea
wing, dark background.
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very clear character for distinguishing the two species apart
is the separation of the compound eyes on the ventral surface
(underside) of the head, as shown in the following figures.
(Character from
Brodo, 1994) |
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Figure
6. Tipula
oleracea ventral
eye space
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Figure
7. Tipula
paludosa ventral
eye space
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