Mucus-secreting Glands in the Paragnaths and second Maxillipeds of the Banana Prawn, Penaeus merguiensis de Man

Abstract

Glands are abundant in the paragnaths and distal endopod segments of the second maxillipeds of Penaeus merguiensis. Seven gland types have been identified and their secretions differentiated into acidic sulfated mucopolysaccharides and carboxylated mucopolysaccharides. In the paragnaths secretions are discharged through groups of pores on the oral and aboral surfaces, and in the second maxillipeds through a dense row of pores on the aboral surface at the propodus-dactylus articulation. Glands are not sexually dimorphic and glandular morphology does not change during the moult cycle. Glandular products probably have a role in feeding by lubricating large particles and entangling particulate matter in mucus.

Functional morphology of the membranous lobe within the preoral cavity of Thenus orientalis (Crustacea: Scyllaridae)

“…Tegumental rosette glands beneath the oral surface contain acidic sulphated mucopolysaccharides and are comparable with those in the metastome of Penaeus merguiensis (McKenzie & Alexander, 1989). Acidic mucopolysaccharides form the basis of muco-compounds which are primarily lubricatory in function (Brimacombe & Webber, 1964) and aid in the passage of food along the oesophagus.…”

“…They did not describe either its structure or role within the preoral cavity, simply stating that it is drawn back during ingestion. Another brief mention of a metastome was made by McKenzie & Alexander (1989) in the banana prawn Penaeus merguiensis de Man. They illustrated the metastome as a small structure at the base of the paragnaths, and reported the presence of tegumental glands that contained acidic sulphated mucopolysaccharides.…”