''Euhexomyza simplicoides'' is a species of

fly Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...

in the family

Agromyzidae The Agromyzidae are a family of flies, commonly referred to as the leaf-miner flies for the feeding habits of their larvae, most of which are leaf miners on various plants. It includes roughly 2,500 species, they are small, some with wing length ...

and forms woody

gall Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants. Plant galls are abnormal outgrowths of plant tissues, similar to benign tumors or war ...

s on many species of

willow Willows, also called sallows and osiers, of the genus ''Salix'', comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions. Most species are known ...

Description

The woody gall is a spindle-shaped swelling tapering into the stem. It is about 2 cm long and at its widest 0.5 cm, but can be indistinct, with the stem barely swollen. Several galls may form around the stem. During the summer there is one white larva in a spherical chamber, which pupates and overwinters in the gall. The

puparium A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages the ...

is yellowish, with bright reddish brown front segments. Goat willow ( ''S. caprea'') is considered to be the main host but has been recorded from many species of

sallow Willows, also called sallows and osiers, of the genus ''Salix'', comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions. Most species are known ...

including ''S. alba'', ''S. triandra'' and ''S. viminalis'' and on the hybrids between them. Also recorded on ''S. aurita'', ''S. cinerea'', ''S. cinerea'' subsp. ''oleifolia'', ''S. pedicellata'' and ''S. repens''

Distribution

Recorded from United States, Austria, Belgium, Finland, France, Germany, Hungary, Italy,

Kyrgyzstan Kyrgyzstan, officially the Kyrgyz Republic, is a landlocked country in Central Asia lying in the Tian Shan and Pamir Mountains, Pamir mountain ranges. Bishkek is the Capital city, capital and List of cities in Kyrgyzstan, largest city. Kyrgyz ...

, Lithuania, Netherlands, Poland, Spain and Switzerland.

Parasitoids

* '' Sphegigaster glabrata'' Graham, 1969 — a

parasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...

wasp.

References

Agromyzidae Diptera of Asia Diptera of Europe Diptera of North America Gall-inducing insects Insects described in 1920 Taxa named by Friedrich Georg Hendel Willow galls {{Opomyzoidea-stub