Blennogeneris

Taxonomy

Family: Tenthredinidae
Family common name: common sawflies
Subfamily: Blennocampinae
Tribe: Lycaotini
Genus: Blennogeneris MacGillivray, 1923
Subgenera: none

Background

The Tenthredinidae are the most species-rich family and are found throughout the world, in all continents but Antarctica. They are known as the “common sawflies.” They can generally be recognized by a cylindrical body and long, segmented antennae. Otherwise, they come in a variety of colors, sizes, and forms (Goulet 1992).

Sawflies in the subfamily Blennocampinae have a diverse set of life histories and habits. Many species are restricted to subtropical and tropical regions, but the genus is still fairly species-rich in North America. Blennocampinae includes many sawflies that feed on ornamental and forestry crops. This subfamily can be recognized by wing venation and bidentate mandibles (Smith 1969d).

Blennogeneris is a genus of medium-sized, mostly black sawflies with reddish legs. Blennogeneris spisspes has an uncommon life history: it develops in bud galls of snowberry (Smith 1969d).

Diversity

There are three described extant species worldwide, and all are restricted to North America (Taeger et al. 2010).

Diagnostic characteristics

Subfamily characters

Genus characters

May be confused with

Blennogeneris can be confused with similar species in the subfamily Blennocampinae. It can be distinguished from most other genera by the complete fore wing anal cell and from similar genus Lycaota by the clear wings and reddish-brown colored legs (Goulet 1992).

Exotic pest species of concern

none

Host associations

In North America, B. spissipes feeds on Symphoricarpos (snowberry) (Smith 1993). Hosts for the other species are unknown (Smith 1969d).

Life history

Blennogeneris spissipes is a gall-inducing sawfly. Females oviposit eggs into terminal leaf buds when the buds first start forming in the spring (Smith 1969d). The galls induced by the larvae are oblong, globular, and somewhat fleshy. They vary in size from 10–35 mm in diameter and often appear in pairs on the bud. The larvae feed inside the gall and make small holes in the walls to push out built-up frass (Larew and Capizzi 1983, Russo 2006). At maturity, the larvae leave the gall and burrow into the soil to overwinter (Ross 1932b, Smith 1969d).

Distribution

World: This genus is known only from North America (Taeger et al. 2010).

North America: Blennogeneris is a generally western genus that occurs in the Pacific Northwest and Rocky Mountain regions, as far south as California, and as far east as Minnesota and Manitoba (Smith 1969d).

Map data from: GBIF.org (29 October 2019) GBIF Occurrence Download Blennogeneris

Details about data used for maps can be found here.

Blennogeneris coloradensis female lateral habitus; photo by Q. Baine, WSDA

Blennogeneris coloradensis female lateral habitus; photo by Q. Baine, WSDA

Blennogeneris coloradensis female dorsal habitus; photo by J. Orr, WSDA

Blennogeneris coloradensis female dorsal habitus; photo by J. Orr, WSDA

Blennogeneris spissipes female face; photo by Q. Baine, WSDA

Blennogeneris spissipes female face; photo by Q. Baine, WSDA

Blennogeneris sp. male lateral habitus; photo by Q. Baine, WSDA

Blennogeneris sp. male lateral habitus; photo by Q. Baine, WSDA

Blennogeneris sp. male dorsal habitus; photo by J. Orr, WSDA

Blennogeneris sp. male dorsal habitus; photo by J. Orr, WSDA

Blennogeneris sp. male face; photo by Q. Baine, WSDA

Blennogeneris sp. male face; photo by Q. Baine, WSDA

Blennogeneris gittinsi fore wing; photo by J. Orr, WSDA

Blennogeneris gittinsi fore wing; photo by J. Orr, WSDA