Species Details

Fenusa dohrnii

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

Common NameEuropean Alder leafminer SeasonalityUnknown in Canada, in Europe and New York state adults are active in mid May (Frankenhuyzen van 1970, Slingerland 1905 cited in Smith 1971). IdentificationAdults: Females only, males not recorded. Small black sawflies approx. 4 mm long. Middle tibia whitish, all tarsi black to whitish but variable. Can be distinguished from Fenusa pumila by length of antennae; are longer than thorax in F. dohrnii (shorter than thorax in F pumila). All sawflies of this group posses an ovipositor modified to be used as a saw to facilitate the deposition of eggs under the surface of leaves. Serrula (teeth) of lancet (saw) low and flat but more obvious than those on the saw of F. pumila. Larvae: Creamy white with a black band on the ventral surface of the thorax, more visible in the later feeding stages. The body is covered in small dark spines and with fewer teeth on the mandibles than Fenusa ulmi or F. pumila. There are 6 instars. The three North American Fenusa species complete development inside leaves of the host plant. Therefore, the larval host is an important diagnostic character. Fenusa dohrnii feeds in Alder, F. pumila on Birch and F. ulmi occurs in eastern North America on Elm. Adapted from Smith 1971.

Scientific Name Fenusa dohrnii Common Name European Alder leafminer Habitat Unknown for adults, larva feeders on wild and ornamental Alder. Seasonality Unknown in Canada, in Europe and New York state adults are active in mid May (Frankenhuyzen van 1970, Slingerland 1905 cited in Smith 1971). Identification
Adults: Females only, males not recorded. Small black sawflies approx. 4 mm long. Middle tibia whitish, all tarsi black to whitish but variable. Can be distinguished from Fenusa pumila by length of antennae; are…
Adults: Females only, males not recorded. Small black sawflies approx. 4 mm long. Middle tibia whitish, all tarsi black to whitish but variable. Can be distinguished from Fenusa pumila by length of antennae; are longer than thorax in F. dohrnii (shorter than thorax in F pumila). All sawflies of this group posses an ovipositor modified to be used as a saw to facilitate the deposition of eggs under the surface of leaves. Serrula (teeth) of lancet (saw) low and flat but more obvious than those on the saw of F. pumila. Larvae: Creamy white with a black band on the ventral surface of the thorax, more visible in the later feeding stages. The body is covered in small dark spines and with fewer teeth on the mandibles than Fenusa ulmi or F. pumila. There are 6 instars. The three North American Fenusa species complete development inside leaves of the host plant. Therefore, the larval host is an important diagnostic character. Fenusa dohrnii feeds in Alder, F. pumila on Birch and F. ulmi occurs in eastern North America on Elm. Adapted from Smith 1971.
Life History
Generally similar to other members of the tribe. Only available description of the life history from Slingerland 1905 (as cited in Smith 1971). Species is believed to be parthenogenic. Females oviposit in the leaf…
Generally similar to other members of the tribe. Only available description of the life history from Slingerland 1905 (as cited in Smith 1971). Species is believed to be parthenogenic. Females oviposit in the leaf surface in the centre part of newly expanded or expanding Alder leaves (Frankenhuyzen van 1970). Larvae feed for approximately 3 weeks before dropping to the ground to pupate. Based on larval activity still being evident in September there are likely multiple generations per year (Smith 1971). Digweed & Langor (2004) observed active larvae in late August and early September in the Northwest Territories, south of the 64th parallel indicating a similar life history in Canada.
Conservation Not of concern, an occasional minor pest throughout its range. Diet Info
Larvae feed in Alder (Alnus), a member of the Betulaceae, from a number of species; Speckled Alder (A. incana subsp rugosa), Mountain Alder (A. incana subsp. tenuifolia), European Alder (A. glutinosa) and A. rugosa
Larvae feed in Alder (Alnus), a member of the Betulaceae, from a number of species; Speckled Alder (A. incana subsp rugosa), Mountain Alder (A. incana subsp. tenuifolia), European Alder (A. glutinosa) and A. rugosa (serrulata). From records in Digweed & Langor 2004 and Smith 1971.
Range North America, Europe, Japan, South Africa (Smith 1971).

Citation

Page Citation for Fenusa dohrnii

Page Citation

"Species Details - Fenusa dohrnii, University of Alberta E.H. Strickland Entomological Museum." University of Alberta Museums Search Site, https://search.museums.ualberta.ca/g/2-5773. Accessed 28 Mar. 2024.

Authorship

Name MacQuarrie, C. J. K.
Role species page author
Date 2004

References

Specimen Information

There are 7 specimens of this Species.

6 results plotted on map in 3 markers.
Note: Only records with latitude and longitude coordinates are plotted on map.

UASM73643 - Fenusa dohrnii

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Banff National Park, Banff Collected ByStrickland, E. H. Date Collected1945-06-19

UASM73644 - Fenusa dohrnii

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Banff National Park, Banff Collected ByStrickland, E. H. Date Collected1949-08-11

UASM73645 - Fenusa dohrnii

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Evansburg Collected ByStrickland, E. H. Date Collected1938-06-30

UASM73646 - Fenusa dohrnii

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Evansburg Collected ByStrickland, E. H. Date Collected1938-06-20

UASM73655 - Fenusa dohrnii

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByStrickland, E. H. Date Collected1937-06-20

UASM73656 - Fenusa dohrnii

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta, Edmonton Collected ByStrickland, E. H. Date Collected1945-08-24

UASM73657 - Fenusa dohrnii

University of Alberta E.H. Strickland Entomological Museum

Place CollectedCanada: Alberta Collected ByStrickland, E. H. Date Collected1932-06-20

Adult Seasonal Distribution