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Dysaphis lauberti

Hawthorn-hogweed aphid

On this page: Identification & Distribution Biology & Ecology Other aphids on the same host

Identification & Distribution

The Dysaphis lauberti fundatrix induces a cherry-red to crimson curled-leaf gall on hawthorn (see first picture below of gall of Dysaphis crataegi species group, (the hawthorn-umbellifer aphids: Dysaphis crataegi, Dysaphis angelicae, Dysaphis apiifolia and Dysaphis lauberti). Neither the leaf gall nor the fundatrix of Dysaphis lauberti can be distinguished from others of the group. Their plump fundatrix is bluish grey and densely powdered with wax. The antennae are short, at about 0.3 times the body length. The terminal process is 1.3-2.0 times the base of the last antennal segment. The siphunculi are quite short, about 0.08-0.09 times the body length and 1.4-1.8 times the cauda. The body length of the fundatrix is 1.7-2.3 mm. The generation produced in the gall are similarly heavily waxed and nearly all develop to winged forms, known as 'spring migrants'. These emigrant alates (not pictured), migrate to Heracleum sphondylium (common hogweed).

Summer colonies of Dysaphis lauberti on hogweed are often found as mixed-species colonies with Anuraphis subterranea, (see second and third pictures below) and/or Dysaphis newskyi, and are attended by ants which tent the colony on the basal leaf sheaths and root collar. Adult apterae of Dysaphis lauberti on the secondary host (see second picture below) are pinkish to greenish grey with orange areas around the siphunculi and wax dusted (cf. Anuraphis subterranea which is greenish-brown to chocolate-brown and not wax-dusted). Hairs on the third antennal segment are maximally 27-56 μm long, distinctly longer and more acute than those on abdominal tergite 3. Secondary rhinaria (up to 26 on antennal segment III, and up to 13 on segment IV) are present only in alatiform apterae, which have dark cross bands on abdominal tergites I-IV. (cf. Dysaphis newskyi which always has secondary rhinaria, with 12-55 on segment III, 0-20 on IV and 0-3 on V). There are usually no marginal tubercles on abdominal tergite VII (cf. Dysaphis newskyi which almost always has marginal tubercles on abdominal tergite VII). The siphunculi are 1.2 - 2.6 times the length of the cauda. The body length of adult Dysaphis lauberti apterae is 1.7-2.6 mm.

The alate Dysaphis lauberti has the bands on its dorsal abdomen fused to form a solid black patch (see second picture below). The longest hair on abdominal tergite III is more than 40 µm long (cf. Dysaphis apiifolia, and Dysaphis crataegi, where that hair is 40 µm or less). The total number of secondary rhinaria on antennal segment V is usually 0-3, and never exceeds 9 (cf. Dysaphis angelica where the total number of secondary rhinaria on antennal segment V (adding both sides together) is 0-31, but is never less than 6 in spring migrants, and usually exceeds 9).

The clarified slide mounts below are of adult viviparous female Dysaphis lauberti : wingless, and winged.

Micrographs of clarified mounts by permission of Roger Blackman, copyright AWP all rights reserved.

The hawthorn - hogweed aphid host alternates between hawthorn (Crataegus spp.) as the primary host and usually hogweed (Heracleum) as the secondary host (occasionally other Apiaceae). On the primary host Dysaphis lauberti induces a deep red curled-leaf gall. Almost all the females of the second generation are winged and migrate. On the secondary host it forms colonies on the lower leaf bases. Dysaphis lauberti has been recorded from Britain and a few other European countries, as well as Turkey and Tajikistan.

 

Biology & Ecology

We have only found Dysaphis lauberti on a single occasion - on Heracleum sphondylium at Seasalter near Whitstable on the Kent coast. The colony was on the leaf sheath of a senescent yellowing leaf on an otherwise completely dried out hogweed plant (see picture below). We have noticed this effect before with aphids (Takecallis arundinariae) feeding on a senescent bamboo leaf. The aphid colony creates a feeding 'sink' which increases the flow of nutrients to the infested part of the leaf, keeping it (more or less) green, while the rest of the plant dies off.

The colony in this case was multispecies: comprised of large numbers of Anuraphis subterranea and a few Dysaphis lauberti. In the picture below, the two large unwaxed aphids are adult apterous Anuraphis subterranea, and the smaller orange-brown unwaxed aphids are the immatures of this species. All the waxed aphids, usually with orange patches around the bases of their siphunculi, are immature Dysaphis lauberti.

Multispecies colonies are quite common with Dysaphis and Anuraphis species, much as we described for Cinara species on larch. The picture below shows the head of a feeding adult Anuraphis subterranea with several wax-powdered Dysaphis lauberti in the background.

 

Other aphids on same host:

Dysaphis lauberti has been recorded from 8 Heracleum species.

Blackman & Eastop list more than 33 species of aphid as feeding on Heracleum species worldwide, and provide formal identification keys.

Of those, Baker (2015) lists 20 as occurring in Britain: Anuraphis subterranea, Aphis brohmeri, Aphis fabae, Aphis spiraecola, Cavariella aegopodii, Cavariella archangelicae, Cavariella konoi, Cavariella pastinacae, Cavariella theobaldi, Dysaphis crataegi, Dysaphis lauberti, Dysaphis newskyi, Hyadaphis foeniculi, Hyadaphis passerinii, Macrosiphum euphorbiae, Macrosiphum gei, Myzus ascalonicus, Myzus ornatus, Myzus persicae and Paramyzus heraclei.

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).

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