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Sea-blite aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host
Identification & Distribution:
Adult Clypeoaphis suaedae apterae are pale olive-green and covered in mealy wax (see first picture below). The terminal process of the sixth antennal segment is slightly shorter than the base of that segment. The antennae of Clypeoaphis suaedae apterae have no secondary rhinaria whilst those of alates have 4-7 on the third antennal segment. The siphunculi are short, tubular or barrel shaped, much longer than their basal width and with a weak flange (see micrograph below). The cauda is thumb-shaped and longer than the siphunculi; its length is more than twice its basal width and it bears 4-9 hairs. Adult apterae of Clypeoaphis suaedae are very small at only 1.2-1.6 mm long.
Clypeoaphis suaedae alates are reputedly rare, and we have yet to find any. Oviparae (see second picture above) have very slightly to moderately swollen hind tibiae. The males are apterous and small. The micrographs below are dorsal and ventral views of a Clypeoaphis suaedae aptera in alcohol.
Clypeoaphis suaedae feeds on Chenopodioideae, especially annual sea-blight Suaeda maritima and Suaeda fruticosa. Oviparae and small apterous males are produced in autumn. The sea-blight aphid is found in Europe, the Middle East, North Africa, Central Asia and Korea.
Biology & Ecology:
We have found this rare species of aphid in two saltmarsh locations in southern England. The first was in Rye Harbour Nature Reserve in East Sussex, and the second was at the Lymington to Keyhaven Nature Reserve in Hampshire. Clypeoaphis suaedae is rare at Rye Harbour, but at Keyhaven we found good populations on a few plants.
Clypeoaphis suaedae is a salt marsh specialist, although little is known about this aphid's adaptations to the marine environment. It has a reputation for being difficult to find and not easily dislodged (Gimingham, 1942) - beaters take note. It is found on annual sea-blight (see picture below) and shrubby sea-blight, plants restricted to salt marshes and sea shores.
Clypeoaphis suaedae uses two methods to escape natural enemies. When the aphid is on the green parts of the plant, the olive-green colour of the aphids is excellent cryptic coloration (see picture below).
An additional method of avoidance, less often used by aphids, is active hiding. Any disturbance to the sea blight aphid sends the aphids down the stem where they are concealed under the leaf sheaths (see picture below taken immediately prior to the aphid disappearing from sight).
The abundance of chrysopid eggs on infested plants (see picture below) suggests that lacewing larvae may be important predators.
Mifsud et al. (2011) reported finding Clypeoaphis suaedae as small colonies or scattered on stems of Suaeda vera and Suaeda maritima in salt marshes in Malta. Joger et al. (2012) reports Clypeoaphis suaedae as one of only 19 aphid species found on plants growing on the dried up floor of the Aral sea (see picture below), surely one of the more hostile environments for any insect.
Other aphids on same host:
Clypeoaphis suaedae has been recorded on 5 Suaeda species (Suaeda fruticosa, Suaeda glauca, Suaeda maritima, Suaeda physophora, Suaeda vermiculata), also on Kochia scoparia and Salsola komarovii.