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Aphids on Tanacetum (tansies)On this page: Species lists Metopeurum fuscoviride Macrosiphoniella tanacetaria Uroleucon tanaceti Aphis fabae Brachycaudus cardui Brachycaudus helichrysi Coloradoa tanacetina Trama troglodytes Species of TanacetumAphids on tansy & feverfewThe 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. 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. Metopeurum fuscoviride (Pink tansy aphid) - a garden tansy specialistMetopeurum fuscoviride is a medium-sized pink or greenish aphid with a large black dorsal spot on the abdomen. It has no wax powdering and no marginal sclerites. The antennal tubercles are very weakly developed, so that the front of head is very shallowly concave. The antennae are 0.9-1.1 times the body length, with a terminal process that is 3.3-5.5 times the base of segment VI. The fused apical segment of the rostrum (RIV+V) is 0.7-0.8 times the length of the second hind tarsal segment (HTII). The siphunculi are dark and thin and 1.3-2.0 times the length of the cauda. The cauda is dusky or dark, elongate triangular with a rather narrow apex, less than 1.7 times longer than its basal width. The body length of Metopeurum fuscoviride apterae is 2.2-2.9 mm.
The alate has marginal sclerites on the abdomen, at least on segments I-III, but the abdomen is otherwise unsclerotized. The siphunculi are 1.2-1.8 times the length of the cauda. The pink tansy aphid feeds on tansy (Tanacetum vulgare) and there is no host alternation. Large colonies can sometimes develop near the stem bases where they are regularly tended by ants, of which Lasius niger is the most common. Sexual forms develop from August onwards, and the species overwinters in the egg stage. Metopeurum fuscoviride is found throughout most of Europe, and is the species we have found most often on tansy in southern England. Macrosiphoniella tanacetaria (Tansy aphid) - a garden tansy specialistMacrosiphoniella tanacetaria apterae (see first picture below) are large wax powdered green or pinkish-brown aphids. The antennae are black including the base of the third segment (cf. Macrosiphoniella artemisiae which has the base of antennal segment 3 brown). The legs, siphunculi and cauda are also black. There are no body hairs on dark scleroites. The antennae are 1.0-1.3 times the body length with the terminal process 2.9-3.5 times the length of the base of the last antennal segment. The siphunculi are 0.1-0.2 times the body length and 0.6-0.9 times the length of the cauda. The body length of apterae is 3.2-4.1 mm. The female alate (see second picture below) is much like the Macrosiphoniella tanacetaria aptera.
The principal host plant of Macrosiphoniella tanacetaria is tansy (Tanacetum vulgare), but the range of reserve hosts seems greater than in most Macrosiphoniella, including records from other Tanacetum species, species of Achillea, Anthemis, Artemisia, Aster, Bidens, Chamaemelum, Chrysanthemum, Dendranthema and Matricaria, and also Salvia officinalis (common sage). 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. Uroleucon tanaceti (Crimson tansy aphid) - a garden tansy specialistApterae of Uroleucon tanaceti are red, reddish brown or crimson, with yellowish antennae and black apices. Body hairs are long and placed on small, discrete scleroites. Antesiphuncular and marginal sclerites are absent. The legs are (usually) yellow with the apices of the tibiae black. The siphunculi are brown or black, often with the middle part paler brown giving a characteristic bicoloured appearance. The cauda is yellow. The body length of Uroleucon tanaceti is 2.2 to 3.4 mm.
The crimson tansy aphid is found on 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. Aphis fabae (Black bean aphid) - a polyphagous species, common on feverfewThe Aphis fabae adult aptera is matt black or very dark brown, sometimes with a distinct greenish hue. It has a variable abdominal sclerotic pattern - confined to abdominal tergites 6-8 in smaller apterae, but broken bands are present in larger ones. Marginal tubercles are protuberant but small. The antennae usually have segments III-IV and the base of V quite pale. The longest femoral and tibial hairs are longer than the least width of the tibia. Their siphunculi and cauda are dark. The black bean aphid immatures (see second picture below) often have discrete white wax spots, as do sometimes the adults. The body length of Aphis fabae adult apterae is 1.2-2.9 mm.
There are several subspecies of Aphis fabae:
Although one can tentatively assign Aphis fabae on the plants above to a particular subspecies, they also colonise a huge range of other plants (for example many umbellifers) which are not associated with a particular subspecies. Also some hosts, such as docks (Rumex spp), seem to be acceptable to all Aphis fabae subspecies. The black bean aphid host alternates between spindle (Euonymus europaeus) as the primary host and many herbaceous plant species 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 parthenogenetically 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. Brachycaudus cardui (Plum-thistle aphid) - a polyphagous species, on garden tansy and feverfewBrachycaudus cardui apterae (see first picture below) are brownish-yellow, pale green or brown, with separate cross bars on thoracic segments, a large shining black spot situated dorsally on the abdomen and 2 or 3 black stripes at the tip. The Brachycaudus cardui rostrum is long and reaches the hind coxae. The longest hairs on abdominal tergite 8 are 85-110 μm long, and the longest hairs on the hind femur are 40-80 μm long. (cf. the short-haired Brachycaudus lateralis. for which the longest hairs on abdominal tergite 8 are 20-61 μm long, and the longest hairs on the hind femur are 10-25 μm long. ) Their siphunculi are black, thick and cylindrical and 1.7-3.4 times the length of their cauda. The body length of apterae is 1.8-2.4 mm.
The alate Brachycaudus cardui (see second picture above) has a large black patch on the dorsal abdomen. Immatures are greenish or reddish. 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). 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. Brachycaudus helichrysi (Leaf-curling plum aphid) - a polyphagous aphidThe adult aptera of Brachycaudus helichrysi (see first picture below) is variable in colour, ranging from yellow to green to pink to white, often shiny with a slight wax dusting. Their antennae are shorter than the body with dusky tips. The dorsum of the abdomen is without a black shield. Their siphunculi are pale, tapered and short - 0.8-2.0 times the length of the cauda. The cauda is pale, short and blunt. The body length of Brachycaudus helichrysi apterae is 0.9 - 2.0mm.
The alate Brachycaudus helichrysi (see second picture above) has a dark dorsal abdominal patch, with 13-46 secondary rhinaria on the third antennal segment and 0-18 on the fourth. The leaf-curling plum aphid host alternates between various plum (Prunus) species (especially domestic plum and blackthorn) and a wide range of Asteraceae such as asters, chrysanthemums, yarrow and groundsel. Brachycaudus helichrysi populations on red clover (Trifolium pratense) have been called var warei, but are not thought sufficiently distinct to warrant subspecific status. This aphid is a serious pest on fruit trees causing the leaves to roll up tightly perpendicular to their mid-rib (see second picture above). Coloradoa tanacetina (Tansy leaf margin aphid) - a rather rare tansy specialistAdult apterae of Coloradoa tanacetina are yellowish green or greenish yellow-brown, with the tips of the antennae and tarsi dark. The antennal terminal process is 1.4-2.0 times longer than the base of antennal segment 6. The last two fused segments of the rostrum (RIV+V) are 0.9-1.0 times longer than the second hind tarsal segment The longest hairs on abdominal tergite 8 are only 14-24 μm. The siphunculi are cylindrical and 1.3-2.2 times longer than the cauda. The length of the adult aptera of Coloradoa tanacetina is 1.1-2.0 mm.
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. Trama troglodytes (Artichoke tuber aphid) - a polyphagous species, mainly on garden tansyTrama troglodytes adult apterae are white, yellowish-white or grey depending on age. Their antennae are about 0.5-0.6 times the body length. The terminal process of the aptera antenna is shorter than the base of the sixth antennal segment (see first micrograph below). The most distinctive character of this aphid is the elongate hind tarsus. The second segment of hind tarsus (HTII) is 0.65-0.82 times the length of the hind tibia (cf. Trama rara which has HTII 0.84-0.92 times the length of the hind tibia). Siphuncular pores are absent (cf. Trama caudata and Trama maritima which both have siphuncular pores). Their cauda is semi-circular. The body length of Trama troglodytes aptera is 2.5-3.9 mm.
The Trama troglodytes alate has dark dorsal sclerites and marginal sclerites (see second picture above - it shows an alate whose wings have been chewed off by an ant). The antenna of the alate has 0-4 secondary rhinaria on segment III, 0-4 on segment IV and 0-6 on segment V. The artichoke tuber aphid lives on the roots of many Asteraceae, especially Achillea, Artemisia, Cirsium and Sonchus. They are invariably attended by ants. Trama troglodytes 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. Species of TanacetumWe 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.
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