Family common name: web-spinning and leaf-rolling sawflies
Genus: Neurotoma Konow, 1897
Neurotoma are web-spinners that spin silk while they feed. Adults are medium-sized, usually patterned, and often colorful. They feed on cherry, plum, peach, almond, and hawthorn trees in North America (Middlekauff 1958).
There are 22 described species worldwide restricted to the Northern Hemisphere. Five species occur in North America, including the introduced N. edwardi (Taeger et al. 2010).
A key to North American species of Neurotoma is included in Middlekauff 1958.
Pamphiliidae are recognized by a somewhat quadrate head and tarsal claws with inner teeth. Neurotoma can be distinguished from Pamphilius and Onycholyda by the lack of fore wing vein Sc1 and the lateral ocellar furrow, and from other genera in the family by the obviously bifid claw, in contrast to a small inner tooth (Goulet 1992).
One Japanese species, N. harai, is unique in that it feeds on Quercus sp. (oak) trees rather than Rosaceae. It is not generally considered a pest in its native range (Shinohara et al. 2018).
Larvae feed on plants of the family Rosaceae, including Prunus serotina (black cherry), P. pennsylvanica (pin cherry), P. americana (American plum), P. domestica (European plum), P. nigra (Canada plum), P. besseyi (sand cherry), P. cerasus (sour cherry), P. tenella (dwarf Russian almond), P. davidiana (Chinese wild peach), Crataegus succulenta (fleshy hawthorn) and C. brainerdi (Brainerd’s hawthorn) (Middlekauff 1958).
Females insert eggs singly or in groups on the underside of leaves alongside a vein. Eggs are long and white/gray. After hatching, larvae spin webs of silk, frass, and leaf matter in which they feed, safe from predators. Some species feed gregariously, others singly in small individual webs on flower buds or leaves. Mature larvae fall to the ground and burrow into the soil where they overwinter. Pupation and emergence occur in the spring. Neurotoma is generally univoltine (Middlekauff 1958).
Neurotoma inconspicua is commonly called the plum web-spinning sawfly and was recorded as a pest in the early twentieth century. Gregarious larvae feed in groups of as many as 46 at a time, sometimes seriously damaging Prunus (cherry, plum) crops in the Midwest (Severin 1920).
World: Neurotoma is known from Europe, including east through Russia and in East Asia, including Japan, Korea, China, and as far south as Thailand (Middlekauff 1988, Taeger et al. 2010, Shinohara et al. 2018).
North America: In North America, Neurotoma is found in the Northeast and Midwest United States and eastern Canada, as far west as eastern British Columbia in the north, and as far south as Virginia in the east (Middlekauff 1958, Middlekauff 1988).
Map data from: GBIF.org (26 June 2019) GBIF Occurrence Download Neurotoma
Details about data used for maps can be found here.