Eriocampa

Taxonomy

Family: Tenthredinidae
Family common name: common sawflies
Subfamily: Allantinae
Tribe: Eriocampini
Genus: Eriocampa Hartig, 1837
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 Allantinae subfamily are mostly black and shining, sometimes with other colors. They have agricultural importance as some species are pests on cultivated and ornamental plants (Smith 1979a). They can be distinguished from other subfamilies by wing venation (Smith 2003a).

Eriocampa are relatively large, about 6–9 mm in length, and fairly robust. All North American species are mostly black and have short antennae (Smith 1979a).

Diversity

There are 28 described species worldwide. Three species occur in North America, two of which are introduced from Europe/West Asia (Taeger et al. 2010).

A Nearctic key to species is included in Smith 1979a.

Diagnostic characteristics

Subfamily characters

Genus characters​

May be confused with

Eriocampa can be confused with similar species in the subfamily Allantinae or tribe Eriocampini. It is most easily recognized by the circular carina forming a ring around the ocellus (Smith 1979a).

Exotic pest species of concern

none

Host associations

In North America, Eriocampa feeds on Juglans nigra (black walnut), Alnus rubra (red alder), A. incana (speckled alder) and A. glutinosa (black alder). In Europe, E. ovata is also recorded on Ulmus (elm) and Corylus (hazel) (Smith 1979a).

Life history

The female Eriocampa lays an egg into the midrib of the leaf. After hatching, the larvae feed externally on the leaves. Larvae are known to secrete a white substance in long trails while feeding, which appears similar to bird fecal matter on the foliage. At maturity they drop to the ground and spin a cocoon in leaf matter at the base of the plant (Mackay and Wellington 1977, Smith 1979a).

Eriocampa ovata in North America is parthenogenetic, and males are not known. It has a bivoltine life cycle (Smith 1979a). Larvae mature through 6–7 instars (Mackay and Wellington 1977).

Distribution

World: This genus is widespread in Europe (Liston 1995) and occurs in China and Taiwan (Wei et al. 2006, Haris 2015).

North America: Eriocampa juglandis is common in the eastern half of the United States north into Ontario. Eriocampa ovata was introduced to the Northeast and Northwest, possibly independently, and now ranges in New England and the Great Lakes area as well as in Washington, British Columbia, and Alaska (Smith 1979a, Discover Life 2019).

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

Details about data used for maps can be found here.

Eriocampa ovata female lateral habitus; photo by J. Orr, WSDA

Eriocampa ovata female lateral habitus; photo by J. Orr, WSDA

Eriocampa ovata female dorsal habitus; photo by J. Orr, WSDA

Eriocampa ovata female dorsal habitus; photo by J. Orr, WSDA

Eriocampa ovata female face; photo by Q. Baine, WSDA

Eriocampa ovata female face; photo by Q. Baine, WSDA

Eriocampa juglandis male lateral habitus; photo by J. Orr, WSDA

Eriocampa juglandis male lateral habitus; photo by J. Orr, WSDA

Eriocampa juglandis male dorsal habitus; photo by Q. Baine, WSDA

Eriocampa juglandis male dorsal habitus; photo by Q. Baine, WSDA

Eriocampa juglandis male face; photo by Q. Baine, WSDA

Eriocampa juglandis male face; photo by Q. Baine, WSDA

Eriocampa ovata wings; photo by P. Jones, WSDA

Eriocampa ovata wings; photo by P. Jones, WSDA