Clupeid fish hosts a Peniculus sp. (Pennellidae, Siphonostomatoida, Copepoda)—First report on new host and season dependent prevalence

Abstract

Pennellid copepod Peniculus fistula fistula (Nordmann, 1832) (Synonym: Peniculus fistula Nordmann, 1832, Aphia ID: 745880), a worldwide distributed species, has been recovered from at least 19 teleost families. The present paper reports for the first time from the Malabar coast (South India), not only the existence of a new host family, Clupeidae, hosting this parasitic copepod species (P. fistula fistula) but also their season dependent hosting. A total of 123 marine fish species, belonging to 77 genera and 38 families surveyed along the Malabar coast, only the clupeid, Anadontostoma chacunda (Hamilton, 1822) was shown to be infected by this copepod species; all the recovered (copepod) parasites were invariably found attached at the mid portion of the caudal fin lobes and lying parallel to the host body, indicating the strict site-specific parasitisation. There is a discrete seasonality in the prevalence (P<0.05) as the sign of infection was noticed during the period from September to May with relatively high prevalence during winter months (November–January). During the monsoon months (June–August), the host fish was found completely free from Peniculus infection. Interestingly, all the 229 recovered specimens (P. fistula fistula) were gravid females having paired uniserrate egg sacs with the length more than its own body length.