Some observations on Pseudomenopon pilosum (Amblycera, Menoponidae), the louse vector of Pelecitus fulicaeatrae (Nematoda, Filarioidea) of coots, Fulica americana (Aves, Gruiformes)

Breeding populations of Pseudomenopon pilosum (Scopoli, 1763) became established on 10 laboratory-reared juvenile American Coots (Fulica americana Gmelin) initially infested with 5 adult male and 5 adult female lice. Eggs of P. pilosum hatched less than 10 days after deposition and the combined duration of the three nymphal instars was 10–20 days. Nymphs and adults occupied all regions of the body. Pseudomenopon pilosum might thus acquire microfilariae of Pelecitus fulicaeatrae (Diesing, 1861) by simply randomly moving to and feeding on the legs where, in infected coots, the skin-inhabiting microfilariae of P. fulicaeatrae are known mainly to occur. Pseudomenopon pilosum occurred on all of 13 adult coots and three 1-week-old coot chicks collected in June in western Canada where P. fulicaeatrae is enzootic. Third-stage larvae of P. fulicaeatrae were found in adult P. pilosum on two of four adult coots harbouring microfilariae, but prevalence in lice was low (5.5% of 18 lice on one coot and 1.1% of 90 on the second) and only one third-stage larva was present in each infected louse. Four other species of lice were present on adult coots but only one other on 1-week-old chicks. Experiments showed that P. pilosum could occur as a straggler on chickens (Gallus gallus (L.)) and Red-necked Grebes (Podiceps grisegena (Boddaert)) although it did not establish on either species.