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Currant - mint aphidsOn this page: Cryptomyzus alboapicalis ballotae galeopsidis korschelti maudamanti ribis
Genus Cryptomyzus [Macrosiphini]Cryptomyzus is a genus of fragile pale whitish, straw-coloured or very pale green aphids the adult viviparae of which may be winged or wingless. The apterae have long antennae and long capitate hairs on the body which are placed on warts. They also often have such hairs on the antennae and legs. The dorsal cuticle in wingless forms is colourless and membranous. The first antennal segment usually has an angular projection at its apex. The siphunculi are thin and either cylindrical or slightly swollen. The cauda is rather blunt. Winged forms have a blackish dorsal patch in front of the siphunculi which may be broken up by colourless lines or patches. The hairs of alates have almost normal apices and are not placed on warts.
There are 17 species worldwide. Typically, Cryptomyzus species retains a sexual stage in their life cycle and host alternate from species of currant (Ribes, in the Grossulariaceae family) where they cause leaf distortion to various species of mint (Lamiaceae). However, some forms live continuously on currant or mint.
Cryptomyzus alboapicalis (White dead nettle aphid) Europe, West Asia
Apterae of Cryptomyzus alboapicalis (see first picture below) are pale greenish with a green median stripe or yellowish with greenish transverse intersegmental stripes. The antennae are much longer than the body, and the antennal terminal process is more than ten times the length of the base of antennal segment VI. The body and appendages have numerous thick, capitate hairs. The siphunculi are slightly swollen and 1.0-1.5 times the length of the cauda. The body length of Cryptomyzus alboapicalis apterae is 1.6-2.9 mm.
Alates of Cryptomyzus alboapicalis (see second picture above) have a dark brown dorsal abdominal patch, deeply indented along the sides.
Cryptomyzus alboapicalis feeds on the undersides of the lower leaves of white dead nettle (Lamium album) and occasionally on other related species. It does not host alternate, and it is not attended by ants. Oviparae and males are produced in autumn, and the species (usually) overwinters in the egg stage. It is found in Britain and across northern and central Europe to western Siberia and the Caucasus.
Cryptomyzus ballotae (Hairy horehound aphid) Europe
Adult apterae of Cryptomyzus ballotae (see first picture below) are dark grey-blue to mottled light green. Their antennae are 1.1 to 1.3 times the body length, with a terminal process that is 5.9-9.0 times the length of the base of antennal segment VI. The apical segment of the rostrum is 1.5-1.6 times the length of the second hind tarsal segment. The body and appendages have numerous thick capitate hairs. Abdominal tergite III of Cryptomyzus ballotae has 2 pairs of equally long spinal hairs, 1-2 pairs of pleural hairs, and 3-5 pairs of marginal hairs. The siphunculi of Cryptomyzus ballotae are swollen on the distal part and are 3.7-4.1 times the length of the rounded triangular cauda. The body length of adult apterae is 1.7-2.1 mm.
The hairy horehound aphid does not host alternate. It feeds on black horehound (Ballota nigra) and other Lamiaceae including white dead-nettle (Lamium album), red dead-nettle (Lamium purpureum) and balm (Marrubium vulgare). Oviparae and alate males have been obtained in the laboratory, but the species is thought to mainly overwinter as parthenogenetic viviparae. Cryptomyzus ballotae is distributed over most of central, western and southern Europe.
Cryptomyzus galeopsidis (European blackcurrant aphid) Europe, West Asia, North America
Adult apterae of Cryptomyzus galeopsidis on their primary host are pale greenish-white, or sometimes yellowish, often with a darker green spinal stripe (see first picture below). Their antennae are longer than the body with the antennal terminal process 9-14 times longer than the base of antennal segment 6. The longest hair on the third antennal segment is distinctly longer than the basal diameter of that segment. Abdominal segments I-V each have 6 thick capitate hairs, two spinal, two pleural and two marginal, arising from tuberculate bases (see first picture below of aptera on its secondary host - hemp nettle) . Their siphunculi have the distal third slightly swollen, and are 1.1-2.1 times longer than the cauda. The body length of apterae is 1.3-2.6 mm.
Cryptomyzus galeopsidis alatae have a large quadrangular dorsal abdominal patch on tergites III-VI, which is more-or-less divided intersegmentally into broad cross bands. Antennal segment III has 40-60 prominent secondary rhinaria. The ovipara is yellowish without a green median stripe. The alate male has a dark dorsal patch and cross bands.
In spring Cryptomyzus galeopsidis lives on the underside of young leaves of blackcurrant (Ribes nigrum) and rarely on other Ribes species. It does not induce a gall on blackcurrant. In June it migrates to hemp nettle (Galeopsis), and other Lamiaceae, where it curls and rolls the young leaves. Some populations do not migrate from Ribes, and are currently regarded as subspecies of Cryptomyzus galeopsidis. The species is common and widespread throughout Britain and Europe, and is also found in the Russian Far East and North America.
Cryptomyzus korschelti (Woundwort aphid) Europe, West & Central AsiaCryptomyzus korschelti apterae, on their secondary host, are pale greenish-yellow with a bright green median stripe and further green mottling over the dorsum. The dorsal body hairs are thick and capitate, much longer than the basal diameter of the third antennal segment, and arising from tuberculate bases (cf. Cryptomyzus stachydis where dorsal body hairs are mostly shorter than the basal diameter of the third antennal segment). The siphunculi are distinctly swollen on the distal half, and are 3.1-3.9 times the length of the cauda (cf. Cryptomyzus ribis which has siphunculi 2.3-3.1 times the length of the cauda and Cryptomyzus galeopsidis which has siphunculi 1.1-2.1 times the length of the cauda). The body length of Cryptomyzus korschelti apterae is 1.6-2.9 mm.
The woundwort aphid host alternates from alpine currant (Ribes alpinum) to hedge woundwort (Stachys sylvatica). On currant they live beneath red or yellow leaf blister galls. Cryptomyzus korschelti is widespread in Britain and Europe eastward to central Asia.
Cryptomyzus maudamanti (Yellow archangel aphid) Europe
Cryptomyzus maudamanti apterae are pale yellow to light green, occasionally with a faint green longitudinal stripe. Their antennae are about 1.5 times the body length, and the terminal process is about 9.6 times the length of the base. The longest hairs on antennal segment III are longer than the basal diameter of that segment, similar in length to those on the antennal segment I. Abdominal tergites I-IV each bear 8-14 capitate hairs. Their rostrum reaches the hind coxae. The siphunculi of Cryptomyzus maudamanti are slightly but distinctly swollen on the distal part (more so than in Cryptomyzus galeopsidis) and about 3-4 times as long as the cauda. The body length of Cryptomyzus maudamanti is 1.1-2.3 mm.
The alate (see clarified mount below) has 3-4 broad, rather short , brown, dorsal cross bars, much like Cryptomyzus galeopsidis.
Cryptomyzus maudamanti host alternates from Ribes rubrum (redcurrant) to Lamium galeobdolon (yellow archangel) and other Lamium species. Oviparae and alate males occur in autumn. Cryptomyzus maudamanti is found in England, Netherlands, Germany, Lithuania, Czech Republic and Italy.
Cryptomyzus ribis (Red currant aphid) Europe, Asia, North America
Cryptomyzus ribis apterae on their primary host are whitish to pale green or yellowish often with a greenish median stripe. The antennae are about 1.2 times the body length, and the terminal process is 9.0-11.5 times the length of the base of antennal segment VI. The longest hair on antennal segment III is much shorter than the longest hair on the inner side of antennal segment I. Their dorsal hairs are thick and capitate. The siphunculi of Cryptomyzus ribis are more or less cylindrical (cf. Cryptomyzus korschelti which has the siphunculi distinctly swollen on the distal half). On the primary host the siphunculi are about 3-4 times the length of the cauda, but on the secondary host they are usually shorter relative to the length of the cauda (2.4 - 3.1 times). The body length of apterae is 1.6-2.3 mm.
The redcurrant aphid host alternates between redcurrant (Ribes rubrum) and woundworts (Stachys spp.). Raised leaf galls are produced on Ribes (see picture above) which are broadly open on the underside where the aphids live. The upperside of the gall turns bright red. Red currant aphids are found throughout Europe, Asia and North America, and can be a serious pest of currant bushes.