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Sapling sycamore aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host Damage & Control
Identification & Distribution:
Immature Drepanosiphum acerinum (see first picture below) are pale yellow-green or pinkish green with long cylindrical siphunculi and red eyes. All adult viviparae are alates. These alates are pale whitish-green to chrome yellow, with thoracic lobes darker (see second picture below). The forewings may have dusky spots at the ends of the veins, but the pigment does not extend between the vein endings (cf. Drepanosiphum aceris which has a dusky patch at the end of the forewing). There are often one or two short brown bars on abdominal tergites 4-5 only (cf. Drepanosiphum platanoidis which never has black bands across abdominal tergites 4-5 only), and usually a conspicuous brown-black spot in front of the base of each siphunculus (see second picture below). The siphunculi are only slightly swollen, and are either entirely or distally dark or black. The long antennae are pale but the segments have brownish tips. The body length of an adult Drepanosiphum acerinum is 2.1- 3.3 mm.
Drepanosiphum acerinum aphids live on sycamore (Acer pseudoplatanus) saplings in the shade. Sexual forms occur in September-October. The species is found throughout Europe, except the Baltic region.
Biology & Ecology:
In Britain Drepanosiphum acerinum is the least common of the four aphid species that live on sycamore - the others are Drepanosiphum platanoidis, Periphyllus acericola and Periphyllus testudinaceus. It is described by Stroyan (1977) as being local. It is the last of these species to hatch from the eggs, well after bud burst in late April when the leaves are nearly fully grown. Unlike the common sycamore aphid, the sapling sycamore aphid reproduces all summer with no aestivation. The picture below shows some immature nymphs we found on sycamore in mid-August.
Wellings (1981) has shown that at high temperatures the growth rate of the sapling sycamore aphid is significantly higher than that of the common sycamore aphid. Dixon & Hopkins (2010) comment that this seems to indicate that it is not poor nutrition but high temperatures that make sycamore a poor host for some other aphid species in mid-summer leading them to aestivate. The picture below shows a Drepanosiphum acerinum adult alate extruding a drop of honeydew.
Oviparae (see pictures below) and males are produced in October.
As with the ovipara of Drepanosiphum aceris, the abdomen behind the siphunculi is produced into an ovipositor-like extension.
After mating, overwintering eggs are laid on the sycamore saplings.
Other aphids on same host:
Drepanosiphum acerinum has been recorded on 7 Acer species (Acer campestre, Acer ibericum, Acer monspessulanum, Acer obtusatum, Acer opalus, Acer pseudoplatanus, Acer pseudoplatanus).
Blackman & Eastop list 12 species of aphid as feeding on sycamore (Acer pseudoplatanus) worldwide, and provide formal identification keys.
Of those aphid species, Baker (2015) lists 8 as occurring in Britain: Aulacorthum solani, Drepanosiphum acerinum, Drepanosiphum dixoni, Drepanosiphum platanoidis, Macrosiphum euphorbiae, Periphyllus acericola, Periphyllus testudinaceus. and Stomaphis graffii.
Damage and control
Drepanosiphum acerinum is a relatively rare species so control is not normally an issue. However, there is evidence that it is a vector of Maple Leaf perforation virus (Sutakova, 1984) which could be a problem for ornamental varieties.