Identification: Patchiella has only one species of aphid, which host alternates between lime trees (Tilia) and the roots of plants in the Araceae family.
Patchiella reaumuri (Lime leaf-nest - Taro root aphid.)
In spring, Patchiella reaumuri forms compact leaf-nest galls (see first picture below) by twisting and stunting the epicormic shoots of Tilia species (lime). These aphids are usually attended by ants, which may remain in the gall unless disturbed but provide the most reliable indicator of the presence of Patchiella reaumuri. The fundatrix (see second picture below) is very dark green or brown, plump-bodied with a body length of about 3.5 mm. The fundatrix has no siphunculi. The immatures which cluster on and around the fundatrix are green, and all develop to alatae. The alate has numerous hairs on its antennae, and 0-3 secondary rhinaria on the fifth antennal segment. The body length of the alate is 2.1-2.7 mm.
The apterae on the secondary host live on the rhizomes of Arum. They are whitish with a powder wax coating.
Patchiella reaumuri host alternates between its winter host lime (Tilia), where it forms a leaf nest, to its summer host - which, in Europe, is mainly cuckoo-pint (Arum maculatum). Males and females occur in autumn and eggs are laid on lime in autumn. The Lime leaf-nest - Taro root aphid has an apparently rather patchy distribution in Europe, including Britain, but is probably underecorded in some countries. Populations in some countries (Hawaii, Solomon Islands) have lost their primary host, and reproduce parthenogenetically all year on the roots of Araceae.
- Blackman, R.L. & Eastop, V.F. (2006). Aphids on the world's herbaceous plants and shrubs. Vols 1 and 2. John Wiley & Sons.