Genus Protrama

Protrama [Tramini]

Protrama are medium to large aphids. The apterae are normally alatiform, with dark dorsal cross bands. The eyes are large and the antennae are about half the body length. The hind tarsus is 0.5-0.9 times as long as the hind tibia. Siphuncular cones are present and are dark, low and hairy. The cauda is rounded.

Protrama feed on underground parts of members of the daisy family, Asteraceae, (especially thistles and wormwoods), or of the buttercup family, Ranunculaceae. Heie (2009) points out that amongst the Lachnini, members of the genera Protrama, Neotrama and Trama are the only ones that do not live on trees as their only host. He poses the questions "What was the original primary host of these species? ... Or did their ancestor conquer herbs as its only host in one step?"

Protrama radicis (thistle root aphid) Europe, South-west & Central Asia

Adult apterae of Protrama radicis are dirty-white to pale-yellow or pale brownish-green. Each segment of the dorsum has a transverse dark sclerotized bar (cf. Trama species which have no dark bars on the dorsum of the aptera). The bars may be more strongly sclerotized (see first picture below, thistle race) or rather less sclerotized (see second picture below, artichoke race). The head and appendages are dark. The antennal terminal process of Protrama radicis is 0.33-0.69 times the length of the base of the sixth antennal segment. The hind tarsus is 0.72-0.87 times the length of the hind tibia (cf. Protrama flavescens where the hind tarsus is only 0.59-0.70 times as long as the hind tibia). Siphunculi are present as pores placed on small brown cones. The body length of the adult aptera is 2.5-3.4 mm. The immatures are yellow brown with small siphuncular pores and resemble the immatures of Trama species.

Until now, only apterae and alatoid apterae have been described - alate Protrama radicis have been unknown. But we have recently reared alatae from a host race of Protrama radicis living on globe artichoke (see third picture above). The alate has sclerotized dorsal bars not quite reaching the marginal sclerites on most or all of the abdominal segments.

Protrama radicis lives in ant attended colonies on the roots of various Asteraceae, especially thistles (Cirsium and Carduus) but also Arctium, Centaurea, and Cynara. They feed on the roots close to the soil surface. They reproduce parthenogenetically throughout the year, and no sexual morphs have been found.

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Acknowledgements Whilst we make every effort to ensure that identifications are correct, we cannot absolutely warranty their accuracy. We have mostly made identifications from high resolution photos of living specimens, along with host plant identity. In the great majority of cases, identifications have been confirmed by microscopic examination of preserved specimens. We have used the keys and species accounts of Blackman & Eastop (1994) and Blackman & Eastop (2006) supplemented with Blackman (1974), Stroyan (1977), Stroyan (1984), Blackman & Eastop (1984), Heie (1980-1995), Dixon & Thieme (2007) and Blackman (2010). We fully acknowledge these authors as the source for the (summarized) taxonomic information we have presented. Any errors in identification or information are ours alone, and we would be very grateful for any corrections. For assistance on the terms used for aphid morphology we suggest the figure provided by Blackman & Eastop (2006).

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References Heie, O.E. (2009). Aphid mysteries not yet solved/Hemiptera:Aphidomorpha/. Monograph: Aphids and other hemipterous insects 15, 31-48.  Full text