Genus Heterarthrus

Heterarthrus

There are 23 species in the genus Heterarthrus primarily located in the palaearctic region. In Britain they are represented by seven species and in Ireland by four species (fiora, microcephalus, nemoratus and vagans).

within the Heterarthrinae, the genus Heterarthrus can be characterised as follows. The antennae have between ten and twelve segments (sometimes more in the males). In dorsal view the head is less gobose than other genera in this sub-family being much wider than it is long. The malar space is about twice the width of the front ocellus. There is no post-genal carina. The prepectus is also absent. On the legs, the tarsal claws are bifid with two subequal teeth close together and with a large basal lobe. The forewing has a complete anal cell with a cross vein. The hindwing lacks both the Rs and the M cells.

The larvae live in blister mines in tree leaves and make a distinctive circular cocoon in the leaf. The host plants are as follows.

AlderHeterarthrus vagans
BirchHeterarthrus nemoratus
Field MapleHeterarthrus wuestneii
Poplars esp. AspenHeterarthrus ochropoda
Sycamore

Heterarthrus cuneifrons

Heterarthrus fiora

WillowsHeterarthrus microcephalus

Species list:

Heterarthrus cuneifrons Altenhofer & Zombori, 1987

Heterarthrus fiora Liston, 2019 = Heterarthrus aceris (Kaltenbach, 1856) in Benson

Heterarthrus microcephalus (Klug, 1818)

Heterarthrus nemoratus (Fallén, 1808)

Heterarthrus ochropoda (Klug, 1818)

Heterarthrus vagans (Fallén, 1808)

Heterarthrus wuestneii (Konow, 1905)

References:

Benson, R.B., 1952. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(a-c), Royal Entomological Society, London

Liston A, Knight G, Sheppard D, Broad G, Livermore L (2014) Checklist of British and Irish Hymenoptera - Sawflies, ‘Symphyta’. Biodiversity Data Journal 2: e1168. https://doi.org/10.3897/BDJ.2.e1168

Liston, A., Mutanen, M. and Viitasaari, M., 2019. On the taxonomy of Heterarthrus (Hymenoptera, Tenthredinidae), with a review of the West Palaearctic species. Journal of Hymenoptera Research, 72, p.83.

Smith, D. R. 1971: Nearctic Sawflies. III. Heterarthrinae: Adults and larvae (Hymenoptera: Tenthredinidae). - Technical Bulletin, U.S. Department of Agriculture, Washington 1420: 1-84

Späth, J. & Liston, A. D. 2003: Bestimmung von Blattminen der Blattwespengattung Heterarthrus an Ahorn (Acer sp.) sowie Neunachweise aus Deutschland. (Hymenoptera, Tenthredinidae). - Nachrichtenblatt der Bayerischen Entomologen, München 52(3/4): 60-70