Internal anatomy of female Paramphiascella fulvofasciata (Copepoda, Harpacticoida)

The gross internal anatomy of females of a harpacticoid copepod, Paramphiascella fulvofasciata Rosenfield and Coull, 1974, was studied using light and transmission electron microscopy. The central nervous system consists of a protocerebrum, connectives, a subesophageal ganglion, and a ventral nerve chain bifurcating twice in the abdomen. The longitudinal musculature of the trunk consists of ventral and dorsal bilaterally symmetrical bundles of muscle fibres. The protractors and dilatators of a swimming leg are attached to tendons of the exoskeleton and the protopodite. The female genital system comprises an unpaired ovary in the frontal portion of the cephalothorax and a pair of oviducts extending towards a chitinized antrum, which lead to the genital apertures or vulvae. The formation of paired egg sacs is discussed. The alimentary tract consists of an esophagus, midgut, and hind gut. A midgut diverticulum is absent. The anus opens between and dorsal to the caudal rami and is overlapped by an anal operculum. Food uptake and fecal pellet formation are discussed.