The histochemistry of the moulting cycle in Gammarus pulex (Crustacea, Amphipoda)

Abstract

The structure and formation of the cuticle of Gammarus pulex L. is described and is found to be basically similar to that of decapod Crustacea. A scheme for designating stages in the moulting cycle is given. The principal food reserve is lipoid which is stored in the digestive gland and extensive adipose connective tissue. Glycogen is stored only in slight quantities, if at all, in intermoult animals, but appears in connective tissues, muscle sarcoplasm and epidermis during pre‐moult. During pre‐moult the muscle sarcoplasm forms an additional site for storing lipoid, which also appears in the epidermis. Following a moult the quantities of lipoid in muscle sarcoplasm and epidermis, and of glycogen in all sites, decline as the new cuticle approaches completion. Calcium is not stored. Animals fed on an enriched diet will store glycogen in all storage sites during intermoult. It is concluded that the lipoid and glycogen appearing in the epidermis are utilized in the formation of the new integument. The possible function of the tegumental glands in the Peracarida is discussed.

Review of the reproductive biology of amphipods and their endocrine regulation: Identification of mechanistic pathways for reproductive toxicants

“…Coordination of the molting of the rigid exoskeleton with the ovarian cycle also facilitates the movement of the newly ovulated oocytes through the oviducts into the marsupium, while the new exoskeleton is still flexible enough to allow their passage [29]. The molt cycle stages for females have been described for the gammaridean amphipods Orchestia gammarella [30] and Gammarus pulex [31] as well as the terrestrial talitridean amphipod O. cavimana [32]. Lipid and protein are required to form the new cuticle [31].…”

“…The molt cycle stages for females have been described for the gammaridean amphipods Orchestia gammarella [30] and Gammarus pulex [31] as well as the terrestrial talitridean amphipod O. cavimana [32]. Lipid and protein are required to form the new cuticle [31]. The principal energy reserve of gammaridean amphipods is lipid, and the main site for its storage is extensive adipose connective tissue in the head and thorax and in the abdomen surrounding the rectum.…”

“…The principal energy reserve of gammaridean amphipods is lipid, and the main site for its storage is extensive adipose connective tissue in the head and thorax and in the abdomen surrounding the rectum. Martin [31] concluded that lipid and glycogen appearing in the epidermis are used in the formation of the new cuticle under the old exoskeleton.…”

Effects of low pH and humus on the survivorship, growth and feeding of Gammarus pulex (L.) (Amphipoda)

“…It was hypothesized that death would occur within 4 days of moulting. At this time the new cuticle is incompletely laid down (within 22% of the moulting cycle; Martin, 1965) and the animal is most sensitive to osmotic stress (Sutcliffe, 1978). This was not clearly corroborated since although mortality did reach a peak about 4 days after moulting, it continued for 20 days (Fig.…”

A Scanning Electron Microscope Investigation of the Effects of Pollutants on the Hepatopancreatic Ceca ofGammarus pulex(L.)

“…These ceca are lined with epithelial cells located on a basement membrane, which is enclosed by a thin muscle network covered with connective tissue: a myoepithelium (Martin, 1965;Schultz, 1976;Schmitz and Scherrey, 1983). The epithelial cells are known to facilitate the digestion of food and assimilation of nutrients (Agrawal, 1965;Schmitz and Scherrey, 1983).…”