Fenella

Taxonomy

Family: Tenthredinidae
Family common name: common sawflies
Subfamily: Heterarthrinae
Tribe: Fenusini
Genus: Fenella Westwood, 1839
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, size and form (Goulet 1992).

Sawflies in the Heterarthrinae subfamily are generally small and dark-colored. Many species of this family are economic pests of trees and shrubs and can be characterized by their skeletonizing or leaf-mining larval feeding behaviors. Heterarthrinae adults can be distinguished from those of other subfamilies by wing venation (Smith 1971a).

Fenella is monotypic in North America. Fenella nigrita females are all black with darkened wings. The male is unknown (Smith 1971a).

Diversity

There are 11 described extant species worldwide. One species occurs in North America (Taeger et al. 2010).

Diagnostic characteristics

Subfamily characters

Genus characters

May be confused with

Fenella can be confused with other genera in the subfamily, especially similar genera Profenusa and Fenusa. It can be distinguished by the number of antennal segments, open cell R1 of the hind wing, and lack of a completely haired mesonotum (Goulet 1992).

Exotic pest species of concern

none

Host associations

Fenella nigrita in North America feeds on Potentilla (cinquefoil) (Smith 1971a).

Life history

The specific biology of F. nigrita is unknown. Larvae are leaf miners (Smith 1971a).

Distribution

World: This genus is known from North America, Europe, North Africa, western Asia, eastern Siberia, Mongolia, Japan, and Korea (Zombori 1978, Taeger et al. 2018)

North America: Fenella nigrita is an introduced species from Europe that was first discovered in North America in Ottawa, Ontario. It now occurs in northeastern states and eastern provinces, as far west as Michigan (Smith 1971a).

Map data from: GBIF.org (29 October 2019) GBIF Occurrence Download Fenella and the Smithsonian National Museum of Natural History Entomology Collection (USNM)

Details about data used for maps can be found here.

Fenella sp. female lateral habitus; photo by J. Orr, WSDA

Fenella sp. female lateral habitus; photo by J. Orr, WSDA

Fenella sp. female dorsal habitus; photo by J. Orr, WSDA

Fenella sp. female dorsal habitus; photo by J. Orr, WSDA

Fenella sp. female face; photo by Q. Baine, WSDA

Fenella sp. female face; photo by Q. Baine, WSDA

Fenella nigrita wings; photo by J. Orr, WSDA

Fenella nigrita wings; photo by J. Orr, WSDA