Tube building by the amphipods Lembos websteri Bate and Corophium bonnellii Milne Edwards

Abstract

Lembos websteri Bate and Corophium bonnellii Milne Edwards are tubicolous. The morphology of tubes collected from Laminaria holdfasts is described and contrasted with that of tubes built amongst filamentous algae in a wave-sheltered environment. In both species tube length is a function of animal length. Corophium build tubes with openings raised above the substratum more commonly than Lembos, and will construct mats of tubes away from solid surfaces; Lembos tend to build against solid surfaces. Tube construction appears to depend upon the ‘knitting’ activity of the first two pairs of peraeopods, utilizing a secretion containing acid and sulphated mucopolysaccharides. The process of tube construction on substrata of known granulometry and the morphology of tubes built in the laboratory are described. The burrowing capabilities of both species are compared. On sand, Lembos tend to build on the sediment surface, whilst Corophium tend to burrow into the substratum. Corophium begin tube building after transference to a new situation much sooner than Lembos, with female Lembos starting to build sooner than male Lembos, Corophium can build a covering tube in < 15 min. In the absence of extraneous material, both species line glass tubes with a meshwork of mucoid filaments. In empty dishes, mucoid tubes are rarely built. The ability of Lembos to colonize wave-exposed sites may be related to its preference for more sheltered spaces within kelp holdfasts.