Family common name: argid sawflies
Genus: Sterictiphora Billberg, 1820
Argidae are found in all non-polar regions of the world (Smith and Middlekauff 1987, Smith 1992). They are external foliage feeders with a wide range of host plants. Additionally, the family exhibits some uncommon behaviors like the excretion of defensive compounds and subsocial habits (Smith 1992).
Sterictiphora are about 6–7 mm in length, and are generally black or orange and black in color. Adults are rarely observed, as they only fly in the early spring. Larvae have a distinct feeding habit that can be easily recognized in the field (Smith 1969c, Eiseman 2015).
A key to North American species of Sterictiphora is included in Smith 1969c.
The family Argidae can be distinguished from other sawflies by the single-segmented flagellum of the antenna. The genus Sterictiphora can be distinguished from other genera in the family by the wing venation, interantennal carina, and the simple tarsal claws. Males differ from related genera Arge and Atomacera because of their conspicuous forked antennae (Smith 1992).
Larvae are external leaf feeders on trees from Rosaceae, most commonly Prunus pensylvanica (fire cherry) and Prunus serotina (black cherry), but also other Prunus sp. and Amelanchier canadensis (Canadian serviceberry) (Smith 1969c).
The female deposits eggs into the margins of leaves. Upon hatching, larvae feed in a unique manner; starting at the leaf margin working towards the midrib, the larva chews a channel, about 8 mm in width and 10 mm in length, that winds back-and-forth in a repeating “S” pattern, much like a meandering river. The body of the larva fits along the curved inside edge as it feeds. Mature larvae are translucent green and measure about 13 mm in length. Prepupae burrow into the soil and construct brown, loosely woven cocoons, in which they overwinter and emerge the following spring (Eiseman 2015).
North America: Sterictiphora generally has two distinct ranges, one west of the Rocky Mountains, and one in the mid-Atlantic north through New England and eastern Canada. There are also records of one species, S. transversa in Alaska and Alberta (Smith 1969c).
Map data from: GBIF.org (26 June 2019) GBIF Occurrence Download Sterictiphora
Details about data used for maps can be found here.