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Aphids on Tanacetum (tansies)Species Overview: Aphid species Metopeurum fuscoviride Macrosiphoniella tanacetaria Aphis fabae Brachycaudus cardui Coloradoa tanacetina Trama troglodytes Uroleucon tanaceti Species of Tanacetum
Aphids on tansy & feverfew
The genus Tanacetum comprises about 160 species of flowering plants (Asteracea), mostly native to the Northern hemisphere. Just two species are native to Britain: Tanacetum vulgare (garden tansy) and Tanacetum parthenium (feverfew) see below.
Blackman & Eastop list 28 aphid species as feeding on plants in the Tanacetum genus worldwide. Of those aphid species, Baker (2015) lists 23 species as occurring in Britain: Aphis fabae, Aphis gossypii, Aphis spiraeola, Aphis vandergooti, Aulacorthum solani, Brachycaudus cardui, Brachycaudus helichrysi, Colaradoa tanacetina, Macrosiphoniella abrotani, Macrosiphoniella artemisiae, Macrosiphoniella millefolii, Macrosiphoniella oblonga, Macrosiphoniella persequens, Macrosiphoniella sanborni, Macrosiphoniella tanacetaria, Macrosiphoniella tapuskae, Macrosiphum euphorbiae, Metopeurum fuscoviride, Myzus persicae, Nasonovia ribisnigri, Pleotrichophorus glandulosus, Trama troglodytes, and Uroleucon tanaceti.
Bell et al. (2015) (Appendix S2) have also published an "annotated checklist of aphids present in the UK". We discuss some of the reasons for the differences between Baker's and Bell's lists in our rare aphids page.
Below are pictures and descriptions of the aphid species we have found most frequently on tansy and/or feverfew in Britain, roughly in order of how often we have encountered them.
The pink tansy aphid mainly feeds on tansy (Tanacetum vulgare). It is regularly tended by ants, of which Lasius niger is the most common. Metopeurum fuscoviride is found throughout most of Europe.
The tansy aphid spends it entire lifecycle on tansy (Tanacetum spp.), chrysanthemum (Chrysanthemum spp.) and mayweed (Matricaria spp.) Colonies occur on upper parts of stem and between the flowers. Eggs are laid on the stem and withered leaves. Macrosiphoniella tanacetaria is common and widespread throughout Europe extending into North Africa, parts of Asia and the Americas.
The black bean aphid host alternates between spindle (Euonymus europaeus) as the primary host and many herbaceous plant species including feverfew (Tancetum parthenium) as secondary hosts. Sexual forms occur in autumn. Aphis fabae is found throughout the northern continents, and has been introduced to many tropical and subtropical countries where it may reproduce parthenogenically all year round. In Europe there is a complex of sibling species or subspecies which can only be distinguished by their choice of secondary host coupled with transfer experiments.
In continental Europe Brachycaudus cardui host alternates between various Prunus species, mainly cherry, plum and apricot, and various wild and cultivated daisies (Asteraceae) especially thistle (Carduus and Cirsium spp.) and borage (Boraginaceae). It is also commonly found on feverfew (Tanacetum parthenium). In Britain it seems to live all year round on Asteraceae. Infested leaves undergo severe curling. Dense colonies occur at the base of flower heads and on the leaves. A return migration to primary hosts occurs in autumn. The plum-thistle aphid is found throughout Britain and Europe as well as in Asia, north Africa and North America.
Winged forms (not shown) have 9-15 secondary rhinaria on antennal segment 3, 5-11 on segment 4 and 1-9 on segment 5.
Coloradoa tanacetina feed in the indentations at the leaf margins of tansy (Tanacetum vulgare). Sexual forms of the aphid (pale green oviparae and very small orange-yellow males) occur in September and October. Coloradoa tanacetina are found across northern Europe, and have been introduced to USA.
The artichoke tuber aphid lives on the roots of many Asteraceae, especially Achillea, Artemisia, Cirsium, Sonchus and Tanacetum. They are invariably attended by ants. These aphids mainly overwinter as parthenogenetic forms, but oviparae and blind wingless males have been found in southern England. Trama troglodytes is found in Europe, west Siberia, Central Asia and Japan.
Second image copyright Nigel Gilligan, all rights reserved
The crimson tansy aphid is found on garden tansy (Tanacetum spp.), especially on the lower yellowing leaves. It also occurs on cultivated Chrysanthemum species. Winged males and wingless female oviparae occur in October. Uroleucon tanaceti is distributed throughout Europe to Siberia and Central Asia, and North America.
We cover two species of Tanacetum, tansy (Tanacetum vulgare) and feverfew (Tanacetum parthenium). Tansy (see first picture below) is a perennial herb with a stout erect stem which grows up to about 80 cm. The leaves are fragrant. alternate and pinnately lobed. The golden-yellow flowers are roundish, flat -topped and button-like and are produced in terminal clusters. The leaves and flowers contain thujone which is toxic.
Feverfew (see second picture above) is also perennial and grows up to around 60 cm high. The leaves are pinnate. It produces many flower heads which have a yellow centre surrounded by white rays. Feverfew has been used as a herbal treatment to reduce fever and treat headaches, but there is little evidence of its efficacy.
Both tansy and feverfew are common herbs throughout Europe, and are now invasive in other parts of the world.