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Genus DysaphisMealy apple gall aphidsOn this page: Dysaphis angelicae apiifolia aucupariae bonomii crataegi crithmi devecta gallica hirsutissima lappae lauberti neostroyani newskyi plantaginea pyri radicola ranunculi sorbi tulipaeGenus Dysaphis [Macrosiphini]On their primary hosts Dysaphis are medium-sized, plump-bodied aphids, greenish, bluish or pinkish grey in colour and covered in wax meal. On their secondary hosts they are oval in shape with less wax. The adult viviparae may be winged or wingless. Characteristic features are the presence of spinal tubercles on head and posterior abdominal segments and short to moderate length tubular siphunculi. The cauda is short and often helmet-shaped. Dysaphis is a Palaearctic genus of about 110 species. Most species retain a sexual stage in their life cycle and host alternate. Spring colonies distort and discolour the leaves of apple and related trees (Maloideae), before migrating to umbellifers (Apiaceae) and other families. Colonies are almost always attended by ants. Several species are important pests of fruit trees. Dysaphis angelicae (Hawthorn - angelica aphid) EuropeThe fundatrix of Dysaphis angelicae induces a cherry-red to crimson curled-leaf gall on hawthorn (see first picture below). Neither the leaf gall nor the fundatrix of Dysaphis angelicae can be distinguished from others of the Dysaphis crataegi species group (the hawthorn-umbellifer aphids: Dysaphis angelicae, Dysaphis apiifolia, Dysaphis crataegi, and Dysaphis lauberti). The plump fundatrix of members of this group is bluish grey and densely powdered with wax. Their 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 (see second picture below) and nearly all develop to winged forms, known as 'spring migrants' or emigrant alates .
The alate can be identified to species. The Dysaphis angelicae emigrant alate has the bands on its doral abdomen fused to form a solid black patch (see third picture above). 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 (adding both sides together) is 0-31, but is never less than 6 in spring migrants, and usually exceeds 9 (cf. Dysaphis lauberti where the total number of secondary rhinaria on antennal segment V is usually 0-3, and never exceeds 9). On their secondary host (angelica), Dysaphis angelicae adult apterae (see fourth picture above) are greyish green with some white wax powdering. They also have a little reddish suffusion around the around the siphunculi, but this is much more prominent in immatures. Their antennae are short - about 0.3 times the body length. Their siphunculi are also quite short at 0.083-0.12 times the body length, but their length is more than twice their basal width. The hawthorn - angelica aphid host alternates between hawthorn (Crataegus spp.) as the primary host and angelica (Angelica sylvestris) as the secondary host. On the primary host Dysaphis angelicae induces a cherry-red leaf gall. All females of the second generation are winged and migrate. On the secondary host it forms colonies on the lower leaf bases. Dysaphis angelicae occurs throughout much of Europe. Dysaphis apiifolia (Hawthorn-parsley aphid) CosmopolitanThe fundatrix of Dysaphis apiifolia induces a cherry-red to crimson curled-leaf gall on hawthorn (see first picture below). Neither the leaf gall nor the fundatrix of Dysaphis apiifolia can be distinguished from others of the Dysaphis crataegi species group (the hawthorn-umbellifer aphids: Dysaphis crataegi, Dysaphis angelicae, Dysaphis apiifolia and Dysaphis lauberti). On the primary host the plump fundatrix (see second picture below) of members of this group is bluish grey and densely powdered with wax. Their 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 of aphids in this species group 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 Dysaphis crataegi fundatrix is 1.7-2.3 mm. Nearly all of the generation produced in the gall are winged (see third picture below) and migrate to the ground level parts of various Apiaceae. These winged adult females are known as 'spring migrants' or emigrant alates
The alate can be identified to species. Most individuals of alate Dysaphis apiifolia (all in summer and autumn) have paired or unpaired marginal tubercles on abdominal tergite VII (cf. Dysaphis crataegi where summer and autumn alatae never have paired marginal tubercles on abdominal tergite VII). The hairs on abdominal tergite VIII are usually short and blunt, rarely more than 30 µm in spring migrants and not more than 26 µm in summer and autumn. (cf. Dysaphis crataegi alates on which the longest hairs on abdominal tergite VIII are 18-87 µm). Apterae on the secondary host (see fourth picture above) are yellowish grey or greenish grey and lightly wax powdered. The longest hairs on abdominal tergite 8 are at most 11-36 µm in length, and rarely greater than 30 µm. Those pictured above were feeding on alexanders (Smyrnium olusatrum) in southern England. The hawthorn-parsley aphid can be found on a wide range of Apiaceae, especially parsley (Petroselinum), but also hemlock (Conium, celery (Apium), fennel (Foeniculum and alexanders (Smyrnium). Dysaphis apiifolia has not been classified into various subspecies determined by the secondary host species. Host alternation is often present in Europe, but permanent parthenogenetic populations are also common in Europe and other parts of the world. Dysaphis aucupariae (Wild service aphid) Europe, Australia, North AmericaThe spring generations of Dysaphis aucupariae live in characteristic reddish to yellowish rolled or twisted pseudogalls on the leaves of Sorbus torminalis (wild service tree) (see first picture below). Apterae of Dysaphis aucupariae on their primary host are heavily wax-powdered (see second picture below). The colour under the wax is greyish green or pinkish yellow with distinctive brownish to reddish areas at siphuncular bases. These reddish areas are often visible on recently ecdysed aphids. The head, antennae (except segment III), legs, siphunculi and cauda are all dark. Their antennae are about 0.6 to 0.7 times the body length. The dorsum of Dysaphis aucupariae is membranous with cross bars on the thorax and abdominal tergites VI and VIII only, and smaller sclerites on other segments. The siphunculi are 2.5 to 3.1 times the length of the triangular cauda. Their body length is 2.2-2.6 mm.
The alate viviparous female Dysaphis aucupariae from the primary host has the abdomen ochreous to greenish-yellow with a black trapeziform dorsal patch on tergites III-V and spinal cross bands on tergites I and II. Apterae on the secondary host are pinkish ochreous with reddish or brownish areas at the siphuncular bases. The alate from the secondary host is reddish ochreous with a blackish sclerotic pattern. Dysaphis aucupariae host alternates from wild service tree to various plantain species (Plantago lanceolata, Plantago media, Plantago major), where they live in the grooves between the veins on the undersides of the leaves. They are often attended by ants. Dysaphis aucupariae is found in Europe east to Crimea and the Caucasus and the Azores. It has (presumably) been introduced to Australia, New Zealand, Argentina and Washington, USA. Dysaphis bonomii (Parsnip mealy gall aphid) EuropeColonies of Dysaphis bonomii are attended by ants which tent the colony on the basal parts of Pastinaca sativa (wild parsnip), sometimes completely covering it with soil particles (see first picture below). The apterae which live under the tenting are pale to dull greyish green and are wax-dusted (see second picture below). The dorsal abdomen has complete dark cross bands on many or all of abdominal tergites 1-8. The siphunculi of Dysaphis bonomii are quite long and slender, 4 times or more longer than their basal diameters (see first micrograph below). The cauda is helmet shaped, a little shorter than its basal width in dorsal view (see second micrograph below). The body length of Dysaphis bonomii aptera is 1.2-2.5 mm.
The Dysaphis bonomii alate viviparous female (see third image above) also has clearly marked black dorsal bands. The parsnip mealy aphid feeds on the basal parts of wild parsnip (Pastinaca sativa), and is attended by ants. It does not host alternate. Apterous males and oviparae occur in the autumn. Dysaphis bonomii has been found in a few European countries, namely (southern England, Sweden, Germany, Austria and Italy). They are monoecious holocyclic with apterous males. Dysaphis crataegi sp. group (Hawthorn - umbellifer aphids) Europe, Asia, North AmericaThe fundatrix of Dysaphis crataegi induces a cherry-red to crimson curled-leaf gall on hawthorn (see first picture below). Neither the leaf gall nor the fundatrix of Dysaphis crataegi can be distinguished from others of the Dysaphis crataegi species group (the hawthorn-umbellifer aphids: Dysaphis apiifolia, Dysaphis angelicae, Dysaphis crataegi and Dysaphis lauberti). The plump fundatrix (see second picture below) of members of this group is bluish grey and densely powdered with wax. Their 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. Dysaphis crataegi 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. Nearly all of the generation produced in the gall are winged (see second picture below) and migrate to the ground level parts of various Apiaceae. These winged adult females are known as 'spring migrants' or emigrant alates
The alate and can be identified to species. Abdominal tergite VII of the Dysaphis crataegi alate never has paired marginal tubercles (cf. Dysaphis apiifolia, alate which usually has paired marginal tubercles on abdominal tergite VII). The total number of secondary rhinaria on the 5th antennal segment of Dysaphis crataegi (adding both sides together) is usually 0-3 (cf. Dysaphis angelicae which has more than 9 secondary rhinaria on the 5th antennal segment). The longest hairs on the third antennal segment of Dysaphis crataegi are 6-19 µm. (cf. Dysaphis lauberti which has the longest hairs on the third antennal segment at 14-35 µm). Apterae on the secondary host (see second picture above) are yellowish grey or greenish grey and lightly wax powdered. The longest hairs on abdominal tergite 8 are again usually >30 µm in length. The hawthorn-carrot aphid comprises a group of closely related subspecies. They all have hawthorn (Crataegus spp.) as the primary host, where they cause deep cherry-red curled-leaf galls in spring and migrate to umbellifers (Apiaceae) in summer. The secondary host depends on the subspecies involved. In western Europe Dysaphis crataegi crataegi migrates to wild carrot (Daucus carota) or sometimes to cow parsley (Anthriscus sylvestris), Dysaphis crataegi kunzei migrates to wild parsnip (Pastinaca sativa), and Dysaphis crataegi aethusae migrates to fools parsley (Aethusa cynapium) and to hedge parsley (Torilis spp.). There are two further subspecies in Asia. As well as the various subspecies of Dysaphis crataegi detailed above, there are also several other hawthorn-feeding host-alternating 'full' species which are difficult to distinguish from Dysaphis crataegi. These include Dysaphis angelicae which migrates to wild angelica (Angelica sylvestris), Dysaphis apiifolia which migrates to parsley (Petroselinum) and sometimes to other umbellifers, and Dysaphis lauberti which migrates to hogweed (Heracleum). Dysaphis crithmi (Rock samphire aphid) Western & Southern EuropeDysaphis crithmi live concealed in the sheathing leaf bases of rock samphire (Crithmum maritimum, see first picture below) growing in sheltered locations. Adult Dysaphis crithmi apterae (see second picture below) are grey to greenish grey, with a reddish area around their siphunculi. The colour is largely obscured by a thick layer of wax-powder. The antennal terminal process is 2.0-3.0 times the length of the base of antennal segment VI. The longest hairs on antennal segment III are 0.6-1.1 times longer than the basal diameter of that segment. The head and abdominal tergites VIII may have very small spinal tubercles. The rather short black siphunculi are only 1.25-2.0 times longer than the cauda. Their cauda is helmet-shaped, not longer than its basal width in dorsal view, with 4-5 hairs. The body length of adult Dysaphis crithmi apterae is 1.7-2.2 mm. Early instars (see third picture below) are pale ochreous, turning to greenish grey with a reddish area around the siphuncular bases as they mature.
Alate Dysaphis crithmi (not pictured here) are pale ochreous greyish on the non-sclerotised parts, with slight wax powdering on the ventral surface. They have large dark marginal marginal sclerites and a black mid-dorsal patch on the abdomen. Dysaphis crithmi colonies live in the sheathing leaf bases of samphire (Crithmum maritimum) growing in sheltered situations, such as rock clefts and crevices in sea walls. Their colonies are usually ant-attended. Dysaphis crithmi is thought to be completely anholocyclic - sexual forms are unknown. It is found in western and southern Europe, including the Iberian peninsula and the Mediterranean islands of Corsica, Malta, and Cyprus. Dysaphis devecta sp. grp. (Rosy leaf-curling apple aphids) EuropeThe Dysaphis devecta species group includes three species: Dysaphis devecta, Dysaphis anthrisci and Dysaphis chaerophylli. All members of the Dysaphis devecta group roll the edges of apple leaves and turn them red to produce a characteristic gall on apple (see first picture below). Late spring colonies of Dysaphis devecta sensu stricto (which do not host alternate) include many apterae or alatiform apterae with sclerotized thorax. Apterae are bluish-grey and wax-powdered (see second picture below). Immature future alatae are dark green to reddish. Late spring colonies of other members of the group (Dysaphis anthrisci & Dysaphis chaerophylli, both of which host alternate) include many immatures and adult alates.
For members of the Dysaphis devecta species complex, the antennae of apterae are shorter than the distance from the frons to the base of the siphunculi, and antennae of alatae are less than the body length (cf. Dysaphis plantaginea which has antennae of apterae at least as long as the distance from the frons to the base of the siphunculi, and those of the alate about as long as the body.) The Dysaphis devecta species group includes Dysaphis anthrisci and Dysaphis chaerophylli. Dysaphis devecta remains all year on apple and has no alternate host. Sexual morphs appear before mid-summer, after only three parthenogenetic generations, and overwintering eggs are laid on apple. Dysaphis anthrisci host alternates between apple and cow parsley (Anthriscus sylvestris). Dysaphis chaerophylli host alternates between apple and the leaf bases of various Chaerophyllum species. Members of the Dysaphis devecta species group are found in Europe. Dysaphis gallica (Ivy-leaved toadflax aphid) EuropeThe aptera of Dysaphis gallica has been described variously as 'leaden coloured' and 'dark mottled blackish green, usually with a reddish tinge at bases of siphunculi'. The reddish tinge is more apparent in fourth instar nymphs (see below). The head has quite prominent antennal tubercles and a scabous median frontal tubercle. Their siphunculi are dusky, dark towards the apices, and are 2.4-3.3 times the length of the short, helmet-shaped cauda. The body length is 1.2-1.6 mm.
The Dysaphis gallica alate has a dark central abdominal patch. It has 27-41 secondary rhinaria on the third antennal segment, 16-35 on the fourth antennal segment and 0-8 on the fifth antennal segment. Dysaphis gallica has mostly been found on their secondary hosts - various members of the Scrophulariaceae, especially Cymbalara muralis (ivy-leaved toadflax), but also Antirrhinum majus (common snapdragon), and Veronica anagallis-aquatica (speedwell). In Britain they repropduce parthenogenetically through the winter, but in northern Germany they host alternate to a primary host, possibly Cotoneaster tomentosus or apple (Malus). Dysaphis gallica has been recorded on its secondary hosts in England, France, Switzerland, Italy, Sicily and Israel. Dysaphis hirsutissima (Hairy mealy root aphid) EuropeColonies of Dysaphis hirsutissima are attended by ants which tent the colony on the basal parts of Anthriscus sylvestris (cow parsley), sometimes completely covering it with soil particles (see first picture below). The adult apterae of Dysaphis hirsutissima are bluish-green with a dark dorsal pattern of paired sclerites and cross-bands (see second picture below). Dorsal hairs are long and very numerous on each tergite. The longest hairs on antennal segment III are 57-97 μm long, 2.5-3.7 times the basal diameter of that segment (cf. Dysaphis anthrisci which has longest hairs on antennal segment III at 26-72 μm and dorsal hairs less numerous and shorter). Immatures of Dysaphis hirsutissima (see third picture above) are also blue-green and are very hairy like the adult, but they lack the black markings. They also have an orange patch around each siphunculus as do immatures of several other Dysaphis species. Dysaphis hirsutissima is found on the stem base and in leaf sheaths of cow parsley (Anthriscus sylvestris). It has only been recorded from Britain, Denmark, the Netherlands, Sweden, Switzerland and Italy, but is probably widespread over most of Europe. Dysaphis lappae (Burdock mealy root aphid) Europe, West Asia, North Africa, South AmericaColonies of Dysaphis lappae are attended by ants which tent the colony on the basal parts of Arctium spp. (burdock), in this case completely covering it with sand and plant fragments (see first picture below). Adult apterae of Dysaphis lappae are dirty olive greenish to brownish, sometimes with a purple tinge (see second picture below). Older adults may have yellowish margins to the abdomen. The rostrum reaches behind the hind coxae. There are rather large marginal tubercles on the prothorax and abdominal segments I-V. The siphunculi are about 1.5-2.0 times the length of the cauda. The body length of female adult apterous Dysaphis lappae is 1.7-2.5 mm.
The alate is pinkish grey, slightly wax powdered with a rather extensive dark dorsal patch (see third picture above). The alate has 37-55 secondary rhinaria on the third antennal segment, 9-19 on the fourth segment and 0-1 on the fifth segment. Dysaphis lappae nymphs are pinkish grey. There are three subspecies with different hosts:
The burdock mealy root aphid lives on the basal parts of stems, root collar and roots of burdock species (Arctium minus, Arctium lappa and Arctium tomentosum ). Sexual forms are found in autumn. It is usually attended by ants. Dysaphis lappae is found in Britain, most of Europe, Transcaucasia, Central Asia, Western Siberia, parts of North Africa and introduced to Brazil. Dysaphis lauberti (Hawthorn-hogweed aphid) Europe, West AsiaThe 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 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. Dysaphis neostroyani (Orchid root-collar aphid) Southern & Eastern EuropeAdult apterae of Dysaphis neostroyani (see largest individuals in two pictures below) are elliptic, generally greenish grey, but orange brown around the siphunculi, and with dark siphunculi and cauda; they are covered with a waxy pulverulence. The head, and bands on the pronotum and tergites VI-VIII are brown sclerotic, as are variably-sized sclerites on the mesonotum, metanotum and tergites I-V. Antennal tubercles and the median frontal tubercle are rather low. The antennae are 6-segmented, with the terminal process 3.1-3.6 times the base of antennal segment VI (cf. Dysaphis eremuri on Liliaceae in Asia, which has that process about twice the base). They are without secondary rhinaria. The longest hair on antennal segment III is 0.6-1.3 times the basal diameter of that segment. The rostrum reaches abdominal segments I-II, with the apical rostral segment (RIV+V) 1.5-1.8 times the second hind tarsal segment (HTII) (cf. Dysaphis tulipae on Liliaceae, which has RIV+V 1.0-1.4 times HTII). The number of hairs on the first tarsal segment is 3, 3, 2 (fore, mid, hind). Protuberant marginal tubercles are always present on the prothorax, and usually on tergites I-V. The siphunculi are cylindrical, narrowed to the apex, and indistinctly S-shaped; they are about twice the length of the cauda. The cauda is shield-shaped, not longer than its basal width, with 4-5 hairs. Body length of adult Dysaphis neostroyani apterae is 1.5-2.4 mm.
Images above copyright Francisco Rodriguez (Faluke) under a creative common licence. The alate Dysaphis neostroyani (not pictured) has a dark head, thorax, a compact central patch on tergites III-V, and bands on tergites VI-VIII. Secondary rhinaria are elliptical, and are distributed 31-50 on antennal segment III, 10-19 on IV and 0-1 on V. Dysaphis neostroyani is monoecious on orchids (Orchidaceae). The species is assumed to be anholocyclic, because no sexuales have been found. It was first found by Ilharco (1965) on the root collar, stems and leaves of the sombre bee orchid (Ophrys fusca) in Portugal. It was later found on Orchis species in southern France and Ukraine. Dysaphis newskyi (Hogweed mealy root aphid) EuropeAdult apterae of Dysaphis newskyi are pinkish to lilac grey and wax dusted (cf. Anuraphis subterranea apterae which are greenish-brown to pinkish-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. The antennae always have secondary rhinaria with 12-55 on segment III, 0-20 on IV and 0-3 on V (cf. Dysaphis lauberti which only has secondary rhinaria in alatiform apterae with dark cross bands on abdominal tergites I-IV). Abdominal tergite VII almost always has a pair of marginal tubercles (cf. Dysaphis lauberti which rarely has marginal tubercles on abdominal tergite VII). The siphunculi are 1.2 - 2.6 times the length of the cauda and do not have close-set rows of minute fine spinules (cf. Anuraphis subterranea which have rows of spicules on their siphunculi). The body length of Dysaphis newskyi apterae is 1-5-2.7 mm. The clarified slide mounts below are of adult viviparous female Dysaphis newskyi : wingless, and winged.
Micrographs of clarified mounts by permission of Roger Blackman, copyright AWP all rights reserved. Dysaphis newskyi does not host alternate, but lives all year round on hogweed (Heracleum spp.). It can be found in ant-attended colonies on the basal leaf sheaths and root collar of its host. The species has been found in Britain, Austria and Italy and more recently in Poland and Finland. Dysaphis plantaginea (Rosy apple aphid) CosmopolitanDysaphis plantaginea is a medium-sized globe-shaped aphid. They induce yellowish crumpled leaf galls on apple in spring (see first picture below). The adult apterae are dull pinkish to slate grey or purplish grey with a greyish-white wax bloom (see second picture below). The antennae of apterae are at least as long as distance from the frons to the base of the siphunculi. The siphunculi of Dysaphis plantaginea are quite long compared to other Dysaphis species, blackish brown and tapered with flanged tips. The cauda is dark, short and triangular. The Dysaphis plantaginea aptera body length is 2.1-2.6 mm.
Alatae from galls (see third picture above) have a reddish-grey abdomen with an extensive dark dorsal patch. The rosy apple aphid host alternates from apple (Malus spp.) where it forms yellowish crumpled leaf galls to plantain (Plantago) where it forms colonies along the veins on the undersides of the leaves. Aphids remain on apple until mid-summer by which time attacked shoots are stunted and twisted. Colonies are often attended by ants. Fruits from infested shoots are small and malformed. Dysaphis plantaginea occurs in Europe, Africa, much of Asia and North and South America. Dysaphis pyri (Pear-bedstraw aphid) Europe, North Africa, Asia, North AmericaDysaphis pyri induce yellowed pseudogalls on Pyrus (pear) in spring (see first picture below). Adult apterae of Dysaphis pyri are medium to rather large globe-shaped, brownish-red to dark brown aphids, thickly coated with grey wax meal (see second picture below). The antennae are pale yellow near the base, but darker towards the apex. The first 5 abdominal tergites have a double row of small dark spots. Hemispherical marginal tubercles are usually present only on abdominal tergites 1-5. The siphunculi are black and perpendicular to the body. They are 3.4-4.1 times their diameter at midpoint, and longer than the cone-shaped cauda. The adult aptera has a body length of 2.1-3.2 mm. Immature Dysaphis pyri are a pale yellowish brown, with reddish suffusion around the bases of their siphunculi (see third picture below). Spring migrant alates have the abdomen brownish-red with a black dorsal patch. They have 23-36 secondary rhinaria on antennal segment III, 2-10 on segment IV and 0-1 on segment V. The primary host of Dysaphis pyri is common pear (Pyrus communis). Leaves and shoots are yellowed and distorted to form a pseudogall. After about three generations on pear, alatae are produced which migrate to the secondary hosts. These are bedstraws, especially hedge bedstraw (Galium mollugo) and cleavers (Galium aparine) and sometimes squincywort (Asperula cynanchica). Dysaphis pyri may form colonies on the roots and prostrate stems, where it is attended by ants. Dysaphis pyri is found throughout Europe, the Middle East, North Africa and Central and South Asia, and has been introduced into the USA. Dysaphis radicola (Apple-dock gall aphid) Europe, Asia, AustraliaColonies of Dysaphis radicola on the basal parts of Rumex (dock) are usually heavily ant-tented with soil particles (see first picture below). Apterae of Dysaphis radicola are greyish-brown to lead grey or greyish-green (see second picture below), and are slightly to moderately wax powdered. Spinal tubercles are present on the head and abdominal tergites VIII, or VII and VIII. The longest hairs on the third abdominal tergite are shorter than the basal diameter of the third antennal segment. Dysaphis radicola siphunculi are 2.0-2.5 times longer than the cauda. Immatures (see third picture below) are grey-green with orange patches around the siphunculi.
The alate of Dysaphis radicola always has marginal tubercles on abdominal tergite 7. In most of Europe Dysaphis radicola host alternates from Malus (apple) to the roots of Rumex (dock). The small primary gall near the apex of the apple leaf produced by the fundatrix comprises a longitudinal fold near the mid-rib (transverse for related Dysaphis species). Subsequent generations roll and redden the lateral margins of leaves of Malus (apple) in the same way as its close relatives. Alates produced in the second generation migrate to the roots of Rumex (dock). This host alternating aspect of Dysaphis radicola biology is lost in British (and other) populations, and the aphids stay on dock all year. On dock the aphids feed at the base of the plant where they are attended by ants. The ants usually tent over the colony with soil particles. Dysaphis radicola occurs throughout Europe, in the Caucasus, in Japan and Australia and possibly the USA. Dysaphis ranunculi (Hawthorn-buttercup mealy gall aphid) Europe, West & Central AsiaThe curled-leaf gall (see first picture below) of Dysaphis ranunculi on hawthorn (Crataegus monogyna) its primary host is pale yellowish-green, often suffused with rosy pink (our gall was yellowish green but had no pink colour). There is no sharp demarcation between the pink of the gall and the green of the leaf lamina (cf. Dysaphis crataegi, where such a demarcation is present). The Dysaphis ranunculi fundatrices are deep blue-grey with a wax bloom, and the immature offspring of the fundatrix are usually brownish grey to grey. The immature offspring in the gall shown were light green with wax markings - hence the identification of this gall as resulting from Dysaphis ranunculi, based on gall-appearance, may not be correct.
Winged forms arise in the second generation and the alate adults migrate to the basal parts of buttercups (Ranunculus spp.). On Ranunculus the adult Dysaphis ranunculi apterae (see second picture above) are mottled grey-green, brownish around the bases of the siphunculi, wax dusted and with variable dark sclerotization. There are usually 9 or more secondary rhinaria on the fifth antennal segment (cf. Dysaphis crataegi, where there are usually 0-1). Immatures (see third picture above) are yellowish green when young, darker green as they mature, and with conspicuous orange-red patches around the siphunculi. Dysaphis ranunculi colonies are attended by ants. There is a return migration to hawthorn in September. The hawthorn-buttercup aphid is found throughout Europe and in central Asia. Dysaphis sorbi (Rowan aphid) Europe, AsiaColonies of Dysaphis sorbi live in large leaf nests on Sorbus aucupariae (rowan) (see first picture below). The mature leaf nest is characterized by the leaf lamina senescing and turning brown, but the mid rib remaining green. The adult apterae are reddish-brown to dark green (see second picture below). The antennae are somewhat shorter than the body. A distinctive feature of the apterae is that they have small but prominent marginal tubercles on abdominal tergites I to VII, just visible on the micrograph of an aptera in alcohol (see below). The pale yellowish siphunculi are cylindrical and slender and are 2.4-3.2 times the length of the cauda. The cauda has 140 hairs. The body length of an adult aptera is 1.8-2.8 mm.
Winged females developing on the primary host have dark antennae and dark slender cylindrical siphunculi, plus an ochreous to reddish yellow abdomen with a dark trapeziform dorsal patch. Dysaphis sorbi is facultatively host alternating, with rowan (Sorbus aucuparia) as its primary host and bellflowers (Campanula) as its secondary host. Winged females are not produced till June and colonies may be found on rowan all year. On the primary host aphids may be found either in leaf galls or on the stems bearing developing berries. Dysaphis tulipae (Tulip aphid) CosmopolitanAdult apterae of Dysaphis tulipae (see first picture below) are pale greenish yellow, but may appear whitish because of an overlay of white powder. There is often a reddish suffusion around the siphunculi which is more prominent in immatures (see second picture below). The longest hairs on the third antennal segment are 10-27 μm, often somewhat blunt apically, and 0.6-1.1 times longer than the basal diameter of that segment. There are spinal tubercles on the head and on abdominal tergite 8. The siphunculi are 1.5-2.0 times the length of the cauda and are slightly thickened in the middle. The body length of the Dysaphis tulipae aptera is 1.7-2.3 mm.
The alate Dysaphis tulipae (see first picture below) has a dorsal patch with lateral extensions which close the space between it and the prominent marginal sclerites. The antennae have 24-55 secondary rhinaria on the third antennal segment, 3-14 on the fourth segment, and none on the fifth. The tulip bulb aphid is found on the bulbs, shoots and leaves of many monocotyledonous plants in the lily and tulip (Liliaceae), crocus, gladiolus and iris (Iridaceae), arum (Araceae) and banana (Musaceae) families. The species is entirely parthenogenetic with no sexual forms. Colonies are commonly ant attended. Dysaphis tulipae has a worldwide distribution apart from South America.
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