INFLUENCE OF MICROPHALLUS SZIDATI MARTORELLI, 1986 (TREMATODA) ON THE FECUNDITY OF THE SECOND INTERMEDIATE HOST, PALAEMONETES ARGENTINUS NOBILI, 1901 (DECAPODA: NATANTIA)

MERLO, M.J.; PARIETTI, M.; ITUARTE R.B.

JOURNAL OF CRUSTACEAN BIOLOGY

CRUSTACEAN SOC

Lugar: Lawrence, Kansas, USA; Año: 2016 vol. 36 p. 94 - 98

0278-0372

Parasites usually have strong negative effects on the fitness of their hosts, as in the reduction of host fecundity. We evaluated the femalefecundity of Palaemonetes argentinus Nobili, 1901 from two populations with contrasting levels of parasitism: the population from NahuelRucá (NR), Argentina that was fully parasitized by a larval digenean (Microphallus szidati Martorelli, 1986) and the population from ElBurro (EB) that was completely free of parasites. Realized and actual fecundity (i.e., number of newly spawned embryos and number ofembryos ready to hatch, respectively) were higher in the parasitized females from NR. Moreover, infected females from NR producedheavier eggs than uninfected ones from EB. Egg loss (estimated as difference between realized and actual fecundity), however, was higherin the parasitized population (18.6 versus 10%). Higher egg loss is likely a negative effect of parasitism; however, the differences infecundity between the two P. argentinus populations may be explained by differences in local ecological conditions. Future studies undercontrolled experimental conditions should compare realized and actual fecundity between parasitized and non-parasitized P. argentinusfrom a same population. Our results highlight the importance of parasitism as a biotic factor to be considered in analyzing life history traitsin shrimp populations.