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Marram flower aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host
Identification & Distribution:
Adult apterae of Laingia psammae are dirty straw-coloured to greyish-green (see first picture above). They have a very elongate body, more than 2.5 times longer than its maximum width. The siphunculi are on abdominal tergite 6 (cf. Atheroides species where the siphunculi are on tergite 5) and are as slightly raised pores with sclerotic rims. Their diameter is greater than that of the hind tibia at midlength. The body length of the adult Laingia psammae aptera is 1.6-2.8 mm.
First image above copyright Thomas Legrand, all rights reserved.
Laingia psammae alates (see second picture above) have dark transverse bars on the dorsal abdomen.
The marram flower aphid is widespread across Europe. It is typically found in the flower heads of marram grass (Ammophila arenaria) on sand dunes, but has also been found on many other grasses such as couch grass (Elymus), reed grass (Calamagrostis) and tufted hair grass (Deschampsia caespitosa) and some sedges e.g. lesser pond sedge (Carex acutiformis). Laingia psammae is sometimes attended by ants. Sexual forms have been found in autumn and at other times of year. It is widely distributed in Europe and across Asia to east Siberia.
Biology & Ecology:
Laingia psammae can be abundant on Ammophila arenaria (marram grass, see picture below) in coastal environments.
We found this species for the first time when we visited Sandwich Bay in Kent. Marram flowers aphids were living, sometimes in large numbers, in the developing seed heads of marram grass (see two pictures below) growing on the beach above the high tide mark. The colonies are seldom attended by ants, and then quite loosely, so there is often plenty of honeydew around the colony.
Laingia psammae do not only feed on the seed heads - Vandegehuchte et al. (2010) also found this species on plants with no inflorescences, living on the leaves. It reached peak densities in early to mid-July, somewhat earlier in the season than another grass feeding aphid, Schizaphis rufula which peaked in late July to early August.
Peña (2016) found the facultative endosymbiont bacteria Serratia symbiotica in all specimens of Laingia psammae sampled from dunes on the Belgian coast. This endosymbiont has been reported to be pivotal in protection against heat shocks in several species of aphids, and in arid areas a relatively high proportion of aphids carry this symbiont (Henry et al., 2013).
We have found no reports in the literature of Laingia psammae predators, but we did find the larvae of two species of Syrphidae (see pictures below) preying on them in marram flower aphids at Sandwich Bay.
We have so far been unable to identify the larval syrphids, but Martens et al. (2011) notes that the highest numbers of (aphidophagous) adult Syrphidae sampled in water traps in dunes on the Belgian coast were the migrants Episyrphus balteatus, Eupeodes corollae and Scaeva pyrastri.
Other aphids on the same host
Blackman & Eastop list 17 species of aphid as feeding on marram grass (Ammophila arenaria) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 13 as occurring in Britain (Show British list).