Aglaostigma

Taxonomy

Family: Tenthredinidae
Family common name: common sawflies
Subfamily: Tenthredininae
Tribe: Tenthredopsini
Genus: Aglaostigma W.F. Kirby, 1882
Subgenera: Aglaostigma, Astochus, Bivena, Macrophyopsis, Neurosiobla

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 Tenthredininae subfamily are relatively large compared to others in the family, often with distinct colorful markings. Some are wasp-like with black and yellow stripes (Goulet 1992). Many species’ life histories are not known. Some Tenthredininae species feed uniquely, as adults, on flower pollen and other insects (Smith 1993). They can be distinguished from other subfamilies by wing venation (Goulet 1992).

Aglaostigma is a widespread, species-rich, relatively large-sized sawfly. In North America they are often orange or red and black in color (Goulet 1992, BugGuide 2019).

Diversity

There are 56 described extant species worldwide. Seven species occur in North America (Taeger et al. 2010).

An incomplete key to Nearctic species is included in Ross 1943a.

Diagnostic characteristics

Subfamily characters

​Genus characters

May be confused with

Aglaostigma can be confused with similar species in the subfamily Tenthredininae. It can be distinguished from most other genera by the angle on the posteroventral area of the metepimeron and lack of an occipital ridge (Goulet 1992).

Exotic pest species of concern

none

Host associations

Aglaostigma in North America feed on a variety of plants from different families, including Sambucus (elderberry) (Smith and Middlekauff 1987) and Galium (bedstraw) (Goulet 1992). Aglaostigma semiluteum is known to feed on Impatiens (jewelweed), including I. capensis (orange jewelweed), and A. quattuordecimpunctatum is known to feed on Podophyllum peltatum (mayapple) (Smith 2006e, Pickering 2009, Smith and Strazanac 2016).

Life history

unknown

Distribution

World: This genus is widespread and known from North America, Europe, North Africa, and Asia (Taeger et al. 2010).

North America: North American Aglaostigma species are split into two general ranges. The western range includes California, British Columbia, Idaho, Nevada, Oregon, and Washington, and the eastern includes New England, Quebec, Ontario, New York, Pennsylvania, Maryland, Ohio, Iowa, Illinois, North Carolina, and Virginia (Ross 1943a).

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

Details about data used for maps can be found here.

Aglaostigma rubens female lateral habitus; photo by Q. Baine, WSDA

Aglaostigma rubens female lateral habitus; photo by Q. Baine, WSDA

Aglaostigma rubens female dorsal habitus; photo by J. Orr, WSDA

Aglaostigma rubens female dorsal habitus; photo by J. Orr, WSDA

Aglaostigma rubens female face; photo by Q. Baine, WSDA

Aglaostigma rubens female face; photo by Q. Baine, WSDA

Aglaostigma rubens male lateral habitus; photo by J. Orr, WSDA

Aglaostigma rubens male lateral habitus; photo by J. Orr, WSDA

Aglaostigma rubens male dorsal habitus; photo by J. Orr, WSDA

Aglaostigma rubens male dorsal habitus; photo by J. Orr, WSDA

Aglaostigma rubens male face; photo by Q. Baine, WSDA

Aglaostigma rubens male face; photo by Q. Baine, WSDA

Aglaostigma rubens fore wing; photo by J. Orr, WSDA

Aglaostigma rubens fore wing; photo by J. Orr, WSDA