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Daisy root aphidsOn this page: Trama Trama caudata Trama maritima Trama rara Trama troglodytes
Trama are medium to large aphids. Apterae are whitish and densely hairy, with small compound eyes and no dark dorsal pigmentation. Their antennae are about 0.5 times the body length, with the antennal terminal process less than 0.25 times the base of antennal segment 6. The hind tarsus is greatly elongated. Most of the species (those in the subgenus Neotrama) have siphuncular pores on low cones, but the three species in the nominate subgenus have neither siphunculi nor siphuncular pores. The cauda is rounded.
There are 14 Trama species worldwide, mostly living on the roots of Asteraceae where they are attended by ants.
Trama (Neotrama) caudata (Garden root aphid)
Adult apterae of Trama caudata (see first picture below) are whitish, pale yellow or brownish with no dark sclerotic bands. Trama caudata is differentiated from the closely related Trama maritima by having a relatively shorter antennal segment III relative to the lengths of antennal segments IV and V. For Trama caudata antennal segment III is 1.80-2.35 × (usually 2.0-2.2 times) the length of antennal segment IV, and 0.90-1.35 times the length of antennal segment V. (cf. Trama maritima for which antennal segment III is 2.1-2.8 times (usually 2.4-2.7 times) the length of antennal segment IV, and 1.35-1.80 times the length of antennal segment V). Siphuncular pores are present on very low cones. The body length of the adult aptera is 2.5-3.3 mm.
Trama caudata feeds on the roots of plants in the daisy family (Asteraceae). They are commonly found on agricultural crops such as chicory (Cichorium) and lettuce (Lactuca), as well as non-cultivated genera including cats ears (Hypochaeris), oxtongues (Picris), hawkbits (Leontodon), sowthistles (Sonchus) and dandelions (Taraxacum). Sexual morphs have not been found, so it is assumed that all reproduction is parthenogenetic and that they overwinter as viviparae. Trama caudata occurs over most of Europe, but has yet to be found in Scandinavia.
Trama (Neotrama) maritima (Coastal root aphid)
Adult apterae of Trama maritima (see first picture below) are whitish, pale yellow or brownish with no sclerotic bands. The species is differentiated from the closely related Trama caudata by having a relatively longer antennal segment III relative to the lengths of antennal segments IV and V. So for Trama maritima antennal segment III is 2.1-2.8 times (usually 2.4-2.7 times) the length of antennal segment IV, and 1.35-1.80 times the length of antennal segment V (cf. Trama caudata for which antennal segment III is 1.80-2.35 × (usually 2.0-2.2 times) the length of antennal segment IV, and 0.90-1.35 times the length of antennal segment V. Siphuncular pores are present on very low, light brown cones. The body length of the adult Trama maritima aptera is 2.6-3.9 mm.
The alate viviparous female (not pictured) has dark dorsal and marginal sclerites on the abdomen. Immature Trama maritima (see second picture above) are usually straw-coloured, sometimes with a green tinge.
Trama maritima live in colonies on the roots of bristly oxtongue (Picris echioides) and spiny sowthistle (Sonchus asper, mainly in coastal regions. They are attended by ants, especially Lasius flavus. Sexual forms have not been found, so it is assumed that they reproduce parthenogenetically through the year.
Trama rara live in ant attended colonies on the roots of dandelion (Taraxacum spp.) and a few other Asteraceae. It is found in Europe, parts of Asia and in North America.
Trama troglodytes (Artichoke tuber aphid)Trama 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 & 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 sclerite (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. 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.