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Aphid Genera : Eriosomatinae
Tribes Eriosomatini, Fordini & PemphiginiOn this page: Tribe Eriosomatini Tribe Fordini Tribe Pemphigini
The Eriosomatinae have 301 species in 48 genera and 3 tribes: the Eriosomatini, Fordini and Pemphigini. More detail
Genus Colopha [Eriosomatini]
Colopha is a small aphid genus, related to the genus Kaltenbachiella. Apterae on the secondary host differ from Kaltenbachiella apterae in having the fore-tarsi parallel-sided, with a ventral hair arising from a distal protrusion. Alatae have a once-branched media in the fore wing and one oblique vein in the hind wing.
There are 6 Colopha species worldwide, all in the northern hemisphere. Three of these have a sexual stage, and host alternate from elm, where they live in cockscomb-like galls, to grasses or sedges, where they live on the roots or aerial parts. Three species have lost their primary host and their sexual stages and live parthenogenetically year-round on grasses and sedges.
Image copyright Maria Fremlin, all rights reserved.
Genus Eriosoma [Eriosomatini]
Both winged and wingless aphids have rather conspicuous siphuncular pores with partially chitinized rims surrounded by a ring of hairs. The forewing of winged individuals usually has only one branch in the medial vein.Most stages are covered in a dense floculent wax.
There are about 35 species most of which host alternate between galls on elm (Ulmaceae) and secondary hosts such as apple (Rosaceae) and currants (Grossulariaceae). They have a sexual stage in the life cycle. They are not attended by ants.
Genus Kaltenbachiella [Eriosomatini]
Kaltenbachiella are a genus of eight species related to Colopha and Tetraneura. But instead of producing a gall on the leaf lamina, first instar Kaltenbachiella fundatrices cause a gall near the base of leaf mid-rib. The hind wing of Kaltenbachiella alates has two oblique veins.
Image copyright Dr László Érsek, all rights reserved.
Genus Paracolopha [Eriosomatini]
Paracolopha aphids induce galls on their primary host, Japanese zelkova (Zelkova serrata). Their antennae are very short and 5-6-segmented, and the tarsi are 1 or 2-segmented. The rostrum is long, with a slender ultimate segment. Wax gland plates are arranged longitudinally on the dorsum in rows. On the exule alate the siphunculi are on abdominal tergite V and are displaced towards the midline. Siphunculi are absent on the emigrant alate.
This genus at present includes two species, Paracolopha morrisoni and Paracolopha takahashii. Paracolopha morrisoni host alternates from Japanese zelkova (Zelkova serrata) to the roots of small bamboos. Paracolopha takahashii is only known from its secondary host, the base of the sedge Carex breviculmis.
Genus Tetraneura [Eriosomatini]
Small aphids. Wingless forms have one-segmented tarsi and the winged forms have a simple, unbranched medial vein in the forewing. Wax gland plates may be present or absent.
About 30 species of which at least seven species host alternate between leaf galls on elm (Ulmaceae) and roots of grasses (Poaceae). They have a sexual stage in the life cycle. The fundatrices induce stalked, pouch-like red, yellow or green galls on the upper sides of leaves. They are not attended by ants.
Genus Aploneura [Fordini]
Aploneura are medium sized aphids. The apterae have very short 4- or 5-segmented antennae. Unlike most root aphids, Aploneura produce copious white wax and probably because of this are not attended by ants. The alatae have very short 6-segmented antennae, the third and fourth segments of which each bear bear a single large secondary rhinaria on the distal half. The wings of the alate are held flat against the abdomen when at rest.
There are only three species in the genus Aploneura. They host alternate betweeen galls on Pistacia and the roots of grasses and vines.
Genus Baizongia [Fordini]
Baizongia aphids produce large galls on their primary host, Pistacia species. In summer they host alternate to grasses where they feed on the roots. In northern areas the populations are anholocyclic on grass roots. The adult apterae on roots have well-developed wax pore-plates, much like Aploneura. The anal aperture is dorsal (as in Geoica) with the hairs on the anal plate and abdominal tergite VIII forming a trophobiotic organ to retain droplets of honeydew until they are removed by ants. The apterae have 5-segmented antennae and the alatae have 6-segmented antennae. These aphids, like for example Forda, Geoica, Paracletus, Prociphilus and some Trama, have no siphunculi. Baizongia alatae hold their wings roof-like when at rest, and the pterostigma has a dark central patch.
Very large populations of Baizongia develop in large, elongate horn-like galls on Pistacia species. Favoured hosts are Pistacea palaestina, Pistacea lentiscus and Pistaceia terebinthus in the Mediterranean, and Pistacea integerrima in northern India.
Guest image copyright George Konstantinou, all rights reserved.
Genus Forda [Fordini]
These are medium-sized aphids. On the primary host they live in galls. The fundatrix initially forms a small temporary gall near the apex of the leaf, but her offspring move to the leaf margin where they form characteristic leaf-edge galls by folding and rolling the leaf margins. Emigrant alates have a dark head and thorax and a pale body. Apterae on the secondary host are often yellowish-white and plump-bodied and are not waxy.
About 10 species host alternating (in the Mediterranean region and south-west Asia) from pistacchio (Pistacia) to the roots of grasses and cereals. Outside the range of Pistacia, several species are known only from their secondary hosts. They are attended by ants on the secondary host and often live in ants' nests.
Image copyright www.aphotofauna.com, all rights reserved.
Genus Geoica [Fordini]
Geoica are small to medium-sized pale-coloured aphids. A characteristic feature of their apterae is the presence of fan-shaped 'spatulate' hairs as well as normal hairs. The anus and anal plate are displaced dorsally, and the anal plate is enlarged to form a trophobiotic organ as in Baizongia. Apterae developing on grasses have 4- or 5-segmented antennae, whereas in alatae the antennae are always 6-segmented. There are no faceted wax glands and, like for example Forda, Baizongia, Paracletus, Prociphilus and some Trama, these aphids lack siphunculi. Geoica alatae have variably developed dorsal abdominal cross-bands, and a rather different trophobiotic organ from that in apterae. The anal plate and cauda are extended laterally to unite and form a sclerotised perianal ring, enclosing a membranous area with the anal aperture at its centre.
Most species of Geoica form globular galls near the bases of leaflets of Pistacia and migrate to and from grass roots. The complete cycle takes two years. Gall-forming populations are present in southern Europe and south Asia where they host alternate to grass roots. Permanently parthenogenetic, grass-feeding populations of two species have become widely distributed in northern Europe, Asia and North America.
Genus Melaphis [Fordini]
The genus Melaphis currently has two named species in North America, Melaphis rhois and the recently named Melaphis asafitchi, but a third species is also believed to be present in America. As far as is known, they all host alternate from sumac to moss.
Melaphis induce galls on their primary host, sumac (Rhus typhina). The galls are globular to pyriform, mottled reddish-pink and green with the gall surface is often irregular or weakly lobed. Antennal tubercles on the aphids are undeveloped and the front of the head is convex. Compound eyes are absent in the aptera, but triommatidia are present in both the aptera and alate. The antenna of alatae are 6-segmented, with a short terminal process. Secondary rhinaria are present in alatae, consisting of narrow annuli on antennal segments III-VI. The rostrum is 4-segmented; the apical segment is conical, with apex rounded. Siphunculi are absent. The cauda is arc-shaped and the anal plate is entire.
Image by permission, copyright Claude Pilon, all rights reserved.
Genus Smynthurodes [Fordini]
Smynthurodes are rather small aphids, the apterae of which have two distinctive characteristics: (a) The second segment of the antenna is distinctly longer than the first, being similar in length to the third segment. (b) The primary rhinaria on the last two segments have thick, hairless, sclerotized rims. The alatae have the forewing veins dark-bordered, and the third antennal segment has numerous hairs, most of which are much longer than basal diameter of that segment.
There is only one species in the genus, Smynthurodes betae. It produces small midrib galls (for fundatrix) or larger leaf-edge galls (for her offspring) on Pistacia in the Mediterranean region, and as far east as Pakistan. The parthenogenetic generations feed on the roots of many dicotyledonous plants.
Genus Grylloprociphilus [Pemphigini]
Grylloprociphilus aphids form large waxy colonies on beech trees. The antennae are 6-segmented. The fore wings have a simple media vein. The hind wings have the media and cubitus originating near the same point. The metafemora (= hind femora) of the sexuparae and of apterae on the secondary host are distinctly larger than the pro- or mesofemora. The cauda is rounded and indistinct.
There is only one species in the genus, Grylloprociphilus imbricator, which lives in North America and host alternates between American beech (Fagus grandifolia) as the primary host and the roots of swamp cypress (Taxodium distichum) as the secondary host.
Images copyright Katja Schulz, Creative Commons.
Genus Mimeuria [Pemphigini]
The Mimeuria genus, in the Pemphigini, contains one species: Mimeuria ulmiphila. It is characterised by the antennal terminal process on both winged and wingless adults being vestigial, less than 0.1 times the length of the base of the last antennal segment. Also the apterae on the secondary host have one-segmented tarsi.
Mimeuria ulmiphila makes a leaf-nest gall on maple.
Image copyright Dr László Érsek, all rights reserved.
Genus Pachypappa [Pemphigini]
About 13 species which host alternate between Populus (poplar) species and the roots of Picea (spruce).
Image copyright Volker Fäßler, all rights reserved.
Genus Patchiella [Pemphigini]
The Patchiella genus has only one species of aphid, which host alternates between lime trees (Tilia) and the roots of plants in the Araceae family.
Genus Pemphigus [Pemphigini]
Small to medium-sized aphids which form galls on poplar. The fundatrix in the gall is covered with wax (removed from the one in the picture to show features). The winged viviparae that emerge from these galls have a black head and pterothorax and a rather elongate greenish wax-dusted abdomen.
There are about 70 species most of which host alternate and have a sexual stage in the life cycle. The primary host is poplar (Populus: Salicaceae) where it induces a gall the leaves and twigs. The secondary host is a herbaceous plant where they form colonies on the roots or in a woolly wax mass above soil level. They are not attended by ants.
Genus Prociphilus [Pemphigini]
The Prociphilus genus contains about 50 species which are fairly evenly distributed through the northern hemisphere. Prociphilus have lost their evolutionary constraint to Populus and transferred their sexual generation in relatively recent times to live in pseudogalls on various more advanced "primary" hosts, e.g. in Rosaceae, Caprifoliaceae and Oleaceae. However, as in the related genus Pachypappa, the parthenogenetic generations have retained an association with the roots of conifers.
Image copyright Alan Watson Featherstone, all rights reserved.
Genus Thecabius [Pemphigini]
Small to medium-sized aphids (alate body length usually 2 - 3 mm) which have short antennae and siphuncular pores. Dorsal wax gland plates are present on all segments producing a dense covering of wax spicules.
About 17 species most of which host alternate and have a sexual stage in the life cycle. The primary host is poplar (Populus: Salicaceae) where it induces a gall on the leaves, petioles or branches. The secondary host is the roots or stems of plants such as buttercups (Ranunculus: Ranunculaceae) and Lysimachia (Myrsinaceae). They are not attended by ants.