Monophadnus

Taxonomy

Family: Tenthredinidae
Family common name: common sawflies
Subfamily: Blennocampinae
Tribe: Phymatocerini
Genus: Monophadnus 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 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).

Monophadnus are medium-sized, about 6.5–7.5 mm in length, and are mostly black with markings of white or red and with short, stocky antennae (Smith 1969d).

Diversity

There are 25 described extant species worldwide. Seven species occur in North America (Taeger et al. 2018).

Diagnostic characteristics

Subfamily characters

Genus characters

May be confused with

Monophadnus can be confused with similar species in the subfamily Blennocampinae. It can be distinguished from most other genera by the fourth antennal segment, which is longer than the third, and the straight apex to fore wing veins 2A and 3A; and from Monophadnoides by the lack of the tarsal claw basal lobe and the presence of hind wing cell M (Smith 1969d, Goulet 1992).

Exotic pest species of concern

none

Host associations

In North America, Monophadnus feeds on species of Ranunculus (buttercup) (Goulet 1992).

Life history

The specific biology of Monophadnus in North America is unknown.

Monophadnus monticola in Europe is recorded sequestering toxic compounds from the host plant. When threatened, the larvae exude hemolymph containing the toxins as a defense against predators. This habit may be present in some North American species as well (Boevé and Müller 2005, Prieto et al. 2007).

Distribution

World: This genus is known from North America, South America, Europe, India, Indonesia, Laos, Japan, China, and Korea (Taeger et al. 2018).

North America: Monophadnus occurs throughout the northern United States and southern Canada, and farther south into California in the west (Smith 1969d).

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

Details about data used for maps can be found here.

Monophadnus pallescens female lateral habitus; photo by J. Orr, WSDA

Monophadnus pallescens female lateral habitus; photo by J. Orr, WSDA

Monophadnus pallescens ​female dorsal habitus; photo by J. Orr, WSDA

Monophadnus pallescens ​female dorsal habitus; photo by J. Orr, WSDA

Monophadnus pallescens ​female face; photo by Q. Baine, WSDA

Monophadnus pallescens ​female face; photo by Q. Baine, WSDA

Monophadnus contortus ​male lateral habitus; photo by Q. Baine, WSDA

Monophadnus contortus ​male lateral habitus; photo by Q. Baine, WSDA

Monophadnus contortus ​male dorsal habitus; photo by J. Orr, WSDA

Monophadnus contortus ​male dorsal habitus; photo by J. Orr, WSDA

Monophadnus contortus ​male face; photo by Q. Baine, WSDA

Monophadnus contortus ​male face; photo by Q. Baine, WSDA

Monophadnus contortus wings; photo by P. Jones, WSDA

Monophadnus contortus wings; photo by P. Jones, WSDA