Family common name: argid sawflies
Genus: Schizocerella Forsius, 1927
Argidae is a family of typical sawflies that 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, this family exhibits some uncommon behaviors like the excretion of defensive compounds and subsocial habits (Smith 1992).
Schizocerella are small, about 4–6 mm in length, and in North America are generally orange and black in color. They are recognized by orange abdominal stripes and short, characteristic 3-segmented antennae, which in males are distinctly forked (Smith 1971c, Smith 1992, Vikberg 2004).
The family Argidae can be distinguished from other sawfies by the single-segmented flagellum of the antenna. The genus Schizocerella can be distinguished from other genera in the family by the orange and black stripes on the abdomen, short antennae, and its lack of a preapical spur. Males are distinguished from related genera Arge and Atomacera by the conspicuous forked antennae (Smith 1992).
The female oviposits into an incision she makes on the edge of a leaf. Up to four eggs are deposited in each leaf. After hatching, larvae feed on the foliage of the plant. The two North American species of Schizocerella feed on the same host and have overlapping ranges, but have distinctly different feeding strategies. S. pilicornis is a leaf-miner and S. lineata is an external defoliator. There are 5 larval instars. At maturity the prepupa drops to the ground, burrows into the top 5 cm of soil, then builds a cocoon of woven fibers and bits of soil. After pupation, the adult chews a small hole in the cocoon, then climbs out of the soil. Adults typically live 25–27 hours, during which time they mate and reproduce (Gorske et al. 1977).
North America: Schizocerella occurs from southern Canada south through Central America (Hartsough et al. 2007).
Map data from: GBIF.org (26 June 2019) GBIF Occurrence Download Schizocerella
Details about data used for maps can be found here.