pilullare were dominant because both ectoparasites have direct life cycle and great capacity for reproduction in eutrophic environments (Marcogliese et al., 2006; Pinheiro, Tavares-Dias, Dias, Santos, & Marinho, 2013; Tavares-Dias et al., 2014; Pantoja et al., 2016), such as the ecosystem investigated here (TavaresDias et al., 2014; Pantoja et al., 2016).
Parasites with direct life cycles like the ectoparasites were, therefore, the most prevalent in this host that inhabit lentic environment, which leads to the accumulation of eggs and larval stages of parasites, especially of these organisms that have a short life-span and high reproduction rate.
For example, winged, flying insects are more likely to be consumed by web spinning or foliage/flower hunting spiders than they are by non-web spinning, ground hunters or burrowing, sit and wait predators, which can be expected to feed primarily on non-flying, mainly fully terrestrial prey and are thus, more likely to be hosts to mermithids with a direct life cycle. Interestingly, the ecology of all but one of the spiders reported by Poinar & Benton (1986) as hosts of A.
The large number of non-web spinning, cursorial Lycosidae (Table 1; 38% of all species, excluding nomina dubia) with undescribed mermithids, suggests that a direct life cycle may be involved in some instances.
Direct life cycles are characterized by direct penetration of the spider host through the integument by the infective stage larva following emergence from the egg.
Capillaria species have direct life cycles and can spread from one fish to another by ingestion of infective larvae.
Even though Capillaria species have direct life cycles a tubifex worm may act as a paratenic (alternative) host and "carry" infective stages of Capillaria to the fish that consumed them.
Direct life cycles involve only one definitive host, whereas indirect life cycles involve a definitive host and one or more intermediate hosts.
Direct life cycles involve a single host where the parasite often spends most of its life (usually as an adult) and where it reproduces.