''Synanthedon flaviventris'', the sallow clearwing, is a moth of the family Sesiidae. The larvae form pear-shaped

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, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...

s on sallows (''Salix'' spp).

Description

The eggs are laid in the

axils A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, st ...

on slender shoots (<10 mm diameter) of sallows, and the first year larva excavates a tunnel which shows no external signs of the larva. In the spring of the following year the larva can be as long as 17–18 mm and tunnels deeper into the tissue of the stem, excavating a vertical tunnel 50–75 mm long and 3 mm in diameter. By the second autumn the frass is pressed into cavities between the bark and wood, and the pear-shaped gall is noticeable. The larva feeds on sallows and their hybrids; eared willow (''

Salix aurita ''Salix aurita'', the eared willow, is a species of willow distributed over much of Europe, and occasionally cultivated. It is a shrub to 2.5 m in height, distinguished from the similar but slightly larger ''Salix cinerea'' by its reddish ...

''), goat willow ('' S. caprea''), creeping willow ('' S. repens''), grey willow ('' S. cinerea''), white willow ('' S. alba''), crack willow ( ''Salix'' × ''fragilis''), European violet willow ('' S. daphnoides'') and rosemary-leaved willow ('' S. rosmarinifolia''). Before pupation, the larva makes an exit hole and the

pupa A pupa ( la, pupa, "doll"; plural: ''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 ...

(11–13 mm long) is yellowish and formed head down in a chamber above the gall. There is no cocoon. Adults have a

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the other wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingspan of ...

of 17–20 mm and are on the wing in June and July. The species has a two-year life cycle, with adults present mostly in even years.

Distribution

It is found in most of

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

(except

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and t ...

, the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

, the

Iberian Peninsula The Iberian Peninsula (), ** * Aragonese and Occitan: ''Peninsula Iberica'' ** ** * french: Péninsule Ibérique * mwl, Península Eibérica * eu, Iberiar penintsula also known as Iberia, is a peninsula in southwestern Europe, defi ...

, most of the

Balkan Peninsula The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...

and

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...

). and

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

(southern Siberia, Baikal, Irkutsk, Chaborowsk, Ussuri).

Notes

References

{{Taxonbar, from=Q2283130 Sesiidae Gall-inducing insects Moths described in 1883 Moths of Asia Moths of Europe Taxa named by Otto Staudinger Willow galls