Seasonal occurrence of Opechona pyriforme metacercariae in the Eirene tenuis population from Laguna Madre, Mexico was analyzed in zooplankton samples collected in October 1997 and January, May, and July 1998. Eirene tenuis medusae were present in May, July, and October, although parasites were found only in October and July samples. Host population density was positively correlated with both surface water temperature and salinity. Total sample prevalence was 3.74%, mean abundance of the parasite was 0.06, and intensity of infection ranged between 1 and 59 metacercariae/host. Prevalence differed significantly among seasons, while intensity of infection did not. Parasite distribution was found to be highly aggregated. Although O. pyriforme infected hydromedusae of all sizes, prevalence was higher in sizes above 2.11 mm umbrella diameter. Additionally, a tendency towards increasing intensity of infection values with increasing umbrella diameter of medusae was observed. This is the first record of E. tenuis as a second intermediate host of O. pyriforme, as well as the first record of this helminth in the Gulf of Mexico.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 97 • No. 1