Morphogenesis of the gut in the nauplius stages of the parasitic copepodLernaea cyprinacea

Post-Embryonic Development of the Copepoda

“…A dorsal diverticulum of the midgut forms at NIII of Euterpina acutifrons (see Fanta, 1972). The tubular foregut of Lemaea cyprinacea develops at Nil but does not become funnel-shaped until NIII, during which stage the midgut begins to form (Benedetti et al, 1992). NIII is the last naupliar stage reported for L. cyprinacea after which a complete gut is present at the first copepodid.…”

Formation of the gut in the first two naupliar stages of Acartia clausi and Hemidiaptomus roubaui (Copepoda, Calanoida): comparative structural and ultrastructural aspects

“…Grobben (1881), in his description of the embryonic and larval development of Calanus finmarchicus (= Cetochilus septentrionalis), mentions that a midgut is already present at stage I (though according to his drawings, it would seem to be probably a nauplius II) and the open hindgut in nauplius III. Among other groups, Benedetti et al (1992), using interferential microscopy, studied the morphogenesis of the gut in the parasitic cyclopoid copepod Lernaea cyprinacea, whose development consists of only three naupliar stages before the copepodid I stage. The midgut arises from granular and agranular cells surrounding the residual yolk mass, by a process resembling that observed in A. clausi, but its differentiation takes place only at the late nauplius III stage and it is fully developed at the early copepodid I stage.…”

“…These works, done mostly during the last three decades, are restricted in the case of calanoid copepods to adult forms (Lowe 1935;Arnaud et al 1978Arnaud et al , 1980Muskó 1988) and copepodids (Hallberg and Hirche 1980;Baldacci et al 1985;Nott et al 1985); some deal with cyclopoids (Defaye et al 1985;Muskó 1986), harpacticoids (Sullivan and Bisalputra 1980;Yoshikoshi 1988aYoshikoshi , 1988b, or the digestive tract of some parasitic species (John and Nair 1975;Briggs 1977;Gresty 1992). Regarding the anatomy of larval stages, only scanty information is available on a free-living harpacticoid (Fanta 1972), cyclopoid (Dudley 1966), and on some parasitic species (Sabatini et al 1987;Benedetti et al 1992), but none of these works have used an ultrastructural approach. The only study of free-living calanoid nauplii dates from the end of the 19th century (Grobben 1881) and the data need to be reconsidered.…”