Tetraneura Ulmi on:
[Wikipedia]
[Google]
[Amazon]
''Tetraneura ulmi'', the elm sack gall aphid and also known as a fig gall, is a species of aphid in the family Aphididae. It was described by Carl Linnaeus and named in his ''
Systema Naturae
' (originally in Latin written ' with the ligature æ) is one of the major works of the Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the system, now known as binomial nomen ...
'', published in 1758. The mite is found in Asia, Europe and North America, causing abnormal plant growths, known as 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 their primary host, elm trees ''( Ulmus'' species). They feed on a secondary host, the roots of various grasses.
Description
The gall is a stalked, club-like smooth pouch (7−15 mm high) on the leaves of elm trees. Feeding inside the gall is a nymph and some wax. Partly formed galls are pale yellow patches with irregular lumpy projections on the top surface of the leaf. On the underside of the leaf, young galls may have a hairy opening.Life cycle
Mature asexual females leave the galls in the summer and lay eggs on grass roots. The aphids are pink, orange or purple, 2–3 mm long and covered in a thin layer of powdered wax. In the autumn, winged forms fly to elms and give birth to wingless mites of both sexes. After mating each female lays an egg and a female nymph hatches in the spring and starts feeding on the underside of a leaf. The leaf reacts by forming a tiny, yellowish pimple on the upper side, which is the early growth of a gall, into which the nymph enters, feeds and produce offspring. Galls have been found on the following species, small-leaved elm ('' Ulmus minor'') and wych elm ('' Ulmus glabra''); rarely on American elm ('' Ulmus americana''), David elm (''Ulmus davidiana
''Ulmus davidiana'', also known as the David elm, or Father David elm, is a small deciduous tree widely distributed across China, Mongolia, Korea, Siberia, and Japan, where it is found in wetlands along streams at elevations of 2000–2300 m ...
''), European white elm (''Ulmus laevis
''Ulmus laevis'' Pall., variously known as the European white elm, fluttering elm, spreading elm, stately elm and, in the United States, the Russian elm, is a large deciduous tree native to Europe, from France northeast to southern Finland, east b ...
'').
References
Further reading
* * *External links
{{Taxonbar, from=Q10693851 Eriosomatinae Insects described in 1758 Insects of Europe Gall-inducing insects Taxa named by Carl Linnaeus