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Aphids on common fleabane (Pulicaria dysenterica)

Species Overview: Ovatus inulae  Brachycaudus helichrysi  Identifying fleabane 

Aphids on common fleabane

Blackman & Eastop list about 11 species of aphids  as feeding on common fleabane worldwide, and provide formal identification keys for aphids on Pulicaria. Of those, 6 species have been recorded by Baker (2015)  as occurring in Britain: Aphis fabae,  Aulacorthum solani,  Brachycaudus helichrysi,  Myzus ornatus,  Myzus persicae,  and Ovatus inulae. 

Note: 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. 

The two species below are those we have found on fleabane most frequently, listed in rough order of abundance. Only one of these - Ovatus inulae - is (more or less) specific to fleabane. Assistance on identifying the plant, common fleabane is given below. 

 

Ovatus inulae (Fleabane aphid)

Adult apterae of Ovatus inulae range from lemon-yellow to pale green in colour. The fused last two segments of the rostrum (RIV+V) are 2.2 - 2.4 times longer than the second segment of the hind tarsus and bears 15-25 small accessory hairs (cf. all other Ovatus  species which have a shorter RIV+V with only 2-6 accessory hairs). The head has a well-developed median frontal tubercle, as well as rounded forwardly directed processes on the antennal tubercles, all clearly visible in the first picture below.

 

The Ovatus inulae alate has a pale greeny-yellow abdomen and a brown thorax. Like the aptera, the last two segments of its rostrum (RIV+V, which are fused) are unusually long - more than 2.2 times longer than the second segment of the hind tarsus.

Ovatus inulae lives all year round on common fleabane (Pulicaria dysenterica). It feeds on the undersides of the leaves and shoot apices, and especially the bases of the flowers. It can also be found on certain Inula and some other Asteraceae species. Sexual forms are produced in the autumn. The species is found throughout Europe into central Asia.

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Brachycaudus helichrysi (Leaf-curling plum aphid)

On its primary host, the adult aptera of Brachycaudus helichrysi (see first picture below) is variable in colour, ranging from yellow to green to brown, often shiny with a slight wax dusting. On its secondary hosts (see second picture below) Brachycaudus helichrysi can be yellow, green, or almost white or pinkish. 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 leaf-curling plum aphid host alternates between various plum (Prunus) species (especially domestic plum and blackthorn) and a wide range of Asteraceae including Pulicaria dysenterica (common fleabane).

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Identifying fleabane

We only look at one fleabane species, the common fleabane (Pulicaria dysenterica) which is native to Europe and western Asia, and is common and widespread in southern England. It is a perennial which is about 60 cm high at maturity and forms dense clusters of plants. Leaves are alternately arranged, densely hairy and clasp the stem. The yellow flowers are composed of a centre of 40-100 disc florets surrounded by 20-30 ray florets.

 

The name 'fleabane' arises because smoke from burning the plant is reputed to drive away fleas and midges. Chemical investigation of the Pulicaria genus has shown the presence of terpenes, diterpenes and sesquiterpenes. Various biological activity, including antibacterial, antifungal and insecticidal properties, has been reported by Khan & Asghari (2012). 

Acknowledgements

We have made provisional 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).

Useful weblinks 

References

  •  Blackman, R.L. & Eastop, V.F. Aphids on the world's plants An online identification and information guide. Full text