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Macrosiphum aphidsOn this page: Genus Macrosiphum Macrosiphum albifrons Macrosiphum cholodkovskyi Macrosiphum euphorbiae Macrosiphum euphorbiellum Macrosiphum funestum Macrosiphum gei Macrosiphum hellebori Macrosiphum ptericolens Macrosiphum rosae Macrosiphum tinctum
Genus Macrosiphum [Macrosiphini]
Macrosiphum are large spindle-shaped pink or green aphids, with long legs and antennae, the latter usually longer than the body. The adult viviparae may be winged or wingless. The antennal tubercles are rather high, smooth, and divergent. Siphunculi are long, flanged and not swollen, with a zone of regular polygonal reticulations covering the one-tenth to one-sixth near the end of the siphunculus. The cauda is always pale and very elongate.
Macrosiphum occur on rose (Rosaceae) and many other hosts including teasel (Dipsacaceae), Apiaceae, Valerianaceae and Ranunculaceae. They usually do not host alternate, although some species retain host alternation with rose as the primary host. They are not attended by ants.
Macrosiphum albifrons (Lupin aphid)
Macrosiphum albifrons apterae are large pale bluish grey-green oval-shaped aphids dusted with white wax (cf. Macrosiphum euphorbiae which is not dusted with wax). Their antennae and legs are pale or dusky with blackish apices. The siphunculi are light brown with dark tips, and are 0.21-0.32 times the body length, and 1.6-2.2 times the length of the cauda. The cauda is pale, slender and rather pointed. The body length of adult Macrosiphum albifrons apterae is 3.2-5.1 mm.
The alate (see second picture above) has a dusky head, brown thorax, a bluish green abdomen with small marginal spots and dusky siphunculi. The alate shown is a teneral - in other words it has just moulted and has yet to produce its wax covering. Mature alates are dusted with wax. Immatures (also in second picture above) have all dark siphunculi and are dusted with wax.
The lupin aphid does not host alternate but spends its entire life cycle on Lupin (Lupinus species). It lives mainly on the leaves, stems and flower spikes. It originates in North America where sexual forms with alate males develop in the autumn, and the aphid overwinters as eggs. In Europe Macrosiphum albifrons was first recorded in England in 1981 where it overwinters as viviparae. It is now widely distributed and considered an invasive pest species over much of Europe.
Macrosiphum cholodkovskyi (Meadow Sweet aphid)
Macrosiphum cholodkovskyi apterae are yellow-green to dark blue-green (see first picture below of a green adult) or coral-pink to red (see second picture below of a pink immature), often with a darker longitudinal mid-dorsal band. The antennae are rather dark except at the bases, and are longer than the body. The femora and tibiae are dark distally. The siphunculi are mainly dusky, with a dark tip and a pale base, and are 1.7-2.2 times the length of the rather thick and blunt cauda. The body length of adult Macrosiphum cholodkovskyi apterae is 3.1-5.1 mm.
The meadowsweet aphid does not host alternate but spends its entire life cycle on meadow sweet (Filipendula ulmaria), and occasionally on valerians (Valeriana alliariifolia). Macrosiphum cholodkovskyi lives on the stem and among the flowers. It is found throughout Europe and parts of Asia.
Macrosiphum euphorbiae (Potato aphid)
Macrosiphum euphorbiae apterae are either green with a darker green longitudinal stripe or red (see pictures below), and often rather shiny. Their eyes are noticeably red, and the antennae are darker towards their tips. The fused apical rostral segment (RIV+V) is 0.83-1.02 times longer than the second hind tarsal segment (HTII) (cf. Macrosiphum tinctum for which RIV+V is 0.98-1.11 times longer than HTII and cf. Macrosiphum funestum for which RIV+V is 1.2-1.5 times longer than HTII). Their femora are brownish and rather pale with the apices not dark or only slightly so (cf. Macrosiphum hellebori, Macrosiphum gei, Macrosiphum cholodkovskyi and Macrosiphum euphorbiellum which all have dark apices to the femora). The siphunculi are pale sometimes with the tips darker, but not as dark as the tips of the tibiae (cf. Macrosiphum rosae which has the siphunculi entirely black). The siphunculi are reticulated on the apical 13-20% and are 1.7-2.2 times the length of the cauda. The cauda is rather pointed and not constricted. The body length of Macrosiphum euphorbiae apterae is 2.0-4.0 mm.
The alate (see third picture above) has pale greenish to yellow-brown thoracic lobes, with only the antennae and siphunculi noticeably darker than in the apterae.
The potato aphid is a common and highly polyphagous species. It is often a pest on various crops such as potato (Solanum tuberosum), lettuce (Lactuca sativa) and beets (Beta vulgaris) as well as on numerous garden ornamentals. Macrosiphum euphorbiae is a vector of about one hundred plant viruses. The species originates from the north-eastern USA where it produces sexual forms and host alternates with rose (Rosa) as its primary host. Elsewhere it usually overwinters as viviparae. Aphid numbers increase rapidly from early spring, and alates spread infestations to other plants. It is an especial problem in unheated greenhouses. Macrosiphum euphorbiae was introduced to Europe about 1917 and is now cosmopolitan.
Macrosiphum euphorbiellum =Macrosiphum amygdaloides (Euphorbia aphid)
Macrosiphum euphorbiellum adult apterae (see first picture below) are usually green, sometimes with a darker green longitudinal stripe, but may also be pink, magenta or wine red. Their eyes are reddish and the antennae are dusky. The antennal terminal process is 4.2-5.2 times longer than the base of the sixth antennal segment. The apical parts of the femora are black (cf. Macrosiphum euphorbiae which has the apical parts of the femora pale or only slightly dusky). The siphunculi are pale with the tips darker. The cauda is rather pointed and not constricted. The body length of Macrosiphum euphorbiellum apterae is 2.0-4.0 mm.
The alate (see second picture above) is similarly coloured to the aptera.
The euphorbia aphid does not host alternate, but spends its entire life cycle on spurge, especially wood spurge (Euphorbia amygdaloides) and red spurge (Euphorbia characias). It feeds on the stems and in the flowerheads. Red oviparous females and red winged males have been found in autumn in Switzerland. Macrosiphum euphorbiellum is found in southern England, southern Ireland and much of central and southern Europe.
Macrosiphum funestum (Blackberry aphid)
The adult apterae of Macrosiphum funestum (see first picture below) are a rather dull green or red. Their antennae are dark or dusky with darker tips to each segment, and are longer than the body. Antennal hairs are long enough to be conspicuous (cf. Sitobion fragariae which has short and blunt antennal hairs less than half the width of the base of antennal segment III). The tips of the tibiae and the ends of the femora are dark. The abdomen is unsclerotized apart from small marginal and antesiphuncular sclerites (cf. Sitobion fragariae which has the dorsum sclerotized). The siphunculi are dusky but not black, and have paler bases (cf. Macrosiphum rosae which has siphunculi entirely black). The siphunculi are about 0.33 times the body length, 2.5-3.5 times the length of the cauda (cf. Sitobion fragariae which has siphunculi 1.7-2.7 times the length of the cauda). The siphunculi are reticulated on the apical 12-15%. The body length of Macrosiphum funestum apterae is 3.0-4.3 mm.
The alate viviparous female (see third picture above) has the abdomen green or red with rather distinct black marginal and antesiphuncular sclerites. The antennae are up to 1.5 times the body length, with segment III bearing 15-33 rhinaria along one side.
The blackberry aphid does not host alternate but spends its entire life cycle on blackberry (Rubus fruticosus agg.). Macrosiphum funestum lives mostly on the young shoots and leaves. Sexual forms are produced in autumn and the aphid overwinters as eggs on the blackberry stems.
Macrosiphum gei (Herb Bennet aphid)
Macrosiphum gei apterae are spindle-shaped, usually mid-green to bluish green (see first picture below) or wine red (see second picture below), occasionally mauve with green mottling. The femora and siphunculi are somewhat darker at the apices. Their antennae are pale at the bases but darker towards the apices. The terminal process of antennal segment VI is 4.5-6 times the length of its base. The hairs on the dorsum of Macrosiphum gei are noticeably long (see first picture below) with the longest hair on abdominal tergite III usually more than 55 μm (cf. Macrosiphum euphorbiae for which the longest hair on abdominal tergite III is usually less than 38 µm). The siphunculi are 1.7-2.1 times the length of the cauda with reticulation on the apical 11-17%. The cauda is rather pointed and not constricted.
The Macrosiphum gei alate (see third picture above) has the head and thorax brown with indistinct marginal sclerites and dark antennae and siphunculi; there are 8-26 secondary rhinaria on the third antennal segment. Immatures (see second picture below) are green or red and may be lightly dusted with wax.
Macrosiphum gei is found in dense colonies on the upper parts of the flower stem of Geum urbanum (herb Bennet, wood avens). It can also occur on the undersides of the leaves of some Apiaceae, especially Anthriscus. Records of this species as a pest of potatoes result from misidentification of Macrosiphum euphorbiae as Macrosiphum gei. It is found in Europe and west Siberia and has been introduced to North America.
Macrosiphum hellebori (Hellebore aphid)
Macrosiphum hellebori apterae (see first picture below) are yellowish green with darker marbling, with dark apices to the antennal segments, femora, tibiae and siphunculi (cf. Macrosiphum euphorbiae in which the femora are entirely pale or slightly dusky distally). The terminal process of antennal segment VI is 6.4-7.9 times the length of its base. The fused apical segment of the rostrum (RIV+V) is 0.8 times the length of the second hind tarsal segment. The siphunculi are 2.2-2.8 times the length of the rather thick and blunt cauda.
Macrosiphum hellebori lives in sometimes large colonies on the undersides of leaves of Helleborus spp. On mainland Europe it overwinters in the egg stage and oviparae and alate males are found in autumn. In Britain it overwinters mainly as viviparae. Macrosiphum hellebori is found in Europe and has been introduced to New Zealand and Australia.ers mainly as viviparae. Macrosiphum hellebori is found in Europe and has been introduced to New Zealand and Australia.
Macrosiphum ptericolens (Bracken aphid)
The apterae (see first picture below of fourth instar) and alates (see second picture below) of Macrosiphum ptericolens are pale yellowish green to a darker shiny green. Their antennae are longer than the body, with the terminal process 5.1-6.5 times the length of the base of antennal segment VI, and 1-15 secondary rhinaria in an irregular row on the basal two fifths of antennal segment III. The abdominal dorsum is pale and smooth, being entirely but lightly sclerotized. The siphunculi are strongly tapering, and have 5-10 rows of distinct reticulations with the reticulated area sometimes distinctly constricted. The siphunculi are 2.7-3.5 times the length of the rather short, tapering cauda. The body length of Macrosiphum ptericolens apterae is 2.3-3.3 mm.
The alate is similar to the apterous viviparous female, but with 38-62 secondary rhinaria on antennal segment III.
The bracken aphid does not host alternate, but spends its entire life cycle on bracken (Pteridium spp.). Macrosiphum ptericolens is indigenous to eastern North America, but has been introduced into England, central Europe and South America.
Macrosiphum rosae (Rose aphid)
Adult Macrosiphum rosae apterae are green or deep pink to red-brown. The antennae and sometimes the head are dark, as are the ends of the tibiae and femora. The abdomen may or may not have small marginal sclerites and antesiphuncular sclerites. The siphunculi are black and bent outwards and are reticulated on the apical 10-17%. They are about 0.27-0.41 times the body length and 1.9-2.4 times the length of the cauda. The cauda is pale yellow. The adult aptera of Macrosiphum rosae is 1.7-3.6 mm long.
Macrosiphum rosae alatae have conspicuous black sclerites along the sides of the abdomen (see third picture above). They also have green and red colour forms. Immatures are similar in appearance to the adult apterae, but the cauda is not developed and the siphunculi are dusky, not black.
The rose aphid usually overwinters in the egg stage on rose bushes (its primary host), although in mild winters some adults may continue to reproduce parthenogenetically. In spring they colonise the young growth of rose, and produce large numbers of alates. These mostly migrate to their secondary hosts, teasels (Dipsaceae) and valerians (Valerianaceae). However, colonies can be found all summer on rose and the species is an important horticultural pest. Macrosiphum rosae has a worldwide distribution.
Macrosiphum tinctum (Green willowherb aphid)
Macrosiphum tinctum apterae are mid to blue green with a darker spinal stripe (see first picture below), or less commonly pink-red (see second picture below). The antennal terminal process is.6-7.1 times the base of the sixth antennal segment. The fused last two segments of the rostrum (RIV+V) are 0.98-1.1 times longer than the second segment of the hind tarsus (cf. Macrosiphum euphorbiae in which (RIV+V) are 0.83-1.02 times longer than the second segment of the hind tarsus). The femora of Macrosiphum tinctum are entirely pale. The dark apical sections of the tibiae are usually markedly swollen to 1.5 or more times their least diameter (cf. Macrosiphum euphorbiae which does not have the apical sections of the tibiae so swollen). The siphunculi are dusky at their apices and are 0.30-0.37 times the body length.
The alate viviparous female (not pictured) has a green (or rarely red) abdomen and, as with the aptera, the dark apical sections of the tibiae are often markedly swollen.
The green willowherb aphid does not host alternate. Macrosiphum tinctum is found on willowherbs (Epilobium species), mainly Epilobium angustifolium (rosebay willowherb) and Epilobium montanum (broad-leaved willowherb).