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Lesser rose aphidIdentification & Distribution Biology & Ecology Damage & Control Other aphids on rose
Identification & Distribution:Wingless adults of Myzaphis rosarum are yellow-green to green with no pleural stripes (cf. Myzaphis bucktoni which has a pair of broad dark stripes converging at the level of the siphunculi). The antennal tubercles are low, but the median tubercle is quadrate and strongly projecting (cf. Myzaphis bucktoni which has the median tubercle rounded). The dorsal cuticle is pitted all over. The siphunculi are quite long, and are slightly swollen and dark-tipped. The cauda is long and conspicuous. The body length of Myzaphis rosarum is 1.2-2.4 mm.
Myzaphis rosarum live all year round on wild and cultivated roses, especially climbers, and frequently also on shrubby Potentilla species. There is no host alternation. They feed mainly along the mid-ribs on both the upper and undersides of young leaves. In Europe oviparae and small dark apterous males appear in November. Myzaphis rosarum is native to Europe, but is now almost cosmopolitan.
Biology & Ecology:
Like many aphid species, Myzaphis rosarum abundance can vary greatly from year to year, hence the standard texts (being based upon relatively few observations) are not always a reliable guide. We only found Myzaphis rosarum for the first time in early April 2015, despite the fact it is regarded as common and a (minor) pest species.
Jaskiewicz (2003) describes the species composition and number of aphids on rose bushes in urban conditions over three years. Myzaphis rosarum appeared on roses late May to early June, reaching maximum numbers in June or early July. They disappeared from one site in late summer, but persisted at the other into December. Lesser rose aphids comprised 6-26% of the aphids feeding on roses.
We have also found that aphids may remain on roses into mid-winter, albeit in the very mild winter of 2015-16. The two pictures below show Myzaphis rosarum in late January on garden rose in Alfriston, East Sussex.
Myzaphis rosarum also occurs on Potentilla (see pictures below).
Damage and control
Myzaphis rosarum is often hidden from view amongst furled leaflets, and may only be noticed when populations are unusually large. It is not considered particularly damaging.
Other aphids on same host:
Blackman & Eastop list about 70 species of aphid found feeding on Rosa (rose) species worldwide, and provide formal identification keys.
The genus Rosa contains perhaps a hundred species, plus hybrids thereof, and thousands of cultivated varieties of 'garden' & agricultural roses. Blackman & Eastop (1984) list thirty-or-so species of aphids that feed on cultivated 'roses', worldwide. Of those aphid species, Baker (2015) lists 12 as occurring in Britain: Chaetosiphon fragaefolii, Chaetosiphon tetrarhodum, Longicaudus trirhodus, Macrosiphum euphorbiae, Macrosiphum rosae, Maculolachnus submacula, Metopolophium dirhodum, Myzaphis bucktoni, Myzaphis rosarum, Rhodobium porosum, Sitobion fragariae and Wahlgreniella nervata.