A New Endoparasitic Oligochaete (Naididae) from a North American Tree-Toad, Hyla squirella Latreille, 1802

Elucidating the Life History and Ecological Aspects ofAllodero hylae(Annelida: Clitellata: Naididae), A Parasitic Oligochaete of Invasive Cuban Tree Frogs in Florida

“…Representative specimens were dehydrated, cleared in clove oil, mounted in damar balsam, and examined with phase-contrast microscopy. Allodero hylae was the only species of Allodero collected from frogs during this study, which were identified by comparisons with paratypes (from the U.S. National Parasitology Collection and Smithsonian Institution) and drawings from Goodchild's (1951) To assess the ability of A. hylae to undergo a morphological change in a free-living environment, worms collected from the ureters of O. septentrionalis were placed in groups of 10-30 worms into 5 cm petri dishes with aged tap water. Tree frog skin and feces, or filtered pond water (Dietz and Alvaredo, 1970), was added to the dish to provide a food source.…”

“…is conjectural, on the basis of limited experimental observations (Lutz, 1927) and field collections (Goodchild, 1951;Harman and Lawler, 1975;Pinder et al, 1998). To our knowledge, Lutz's (1927) experiments are the only attempt to culture a species of Allodero in a free-living environment, and he suggested that these worms may require a free-living stage in their life cycle.…”

“…More important, host specificity of A. hylae appears to vary geographically, with worms infecting H. cineria, but not sympatric H. squirella and H. versicolor in Mississippi (Harman and Lawler, 1975), whereas worms infected H. squirella and H. versicolor in Louisiana, but not sympatric H. cineria (Harman, 1973). Further, Goodchild (1951) found A. hylae infecting H. squirella but not sympatric H. cineria. Such local host specificity has not been explained in A. hylae, but previous studies (e.g., Bolek and Janovy, 2007;Langford and Janovy, 2013) have found that parasites of amphibians may exploit different subsets of hosts across their geographic ranges.…”

“…Further, it is unknown whether worms infect tadpoles or adult frogs (or both) or in what environment transmission occurs. Goodchild (1951) suggested that Allodero hylae relied upon the host's breeding season to prompt sexual reproduction and produce an infective generation that could infect tadpoles. Harman and Lawler (1975) conducted field studies to test Goodchild's hypothesis and found no infected tadpoles or young-of-the-year frogs from a small breeding pond with infected adult tree frogs, thus concluding that A. hylae is not transmitted in the breeding pond and may have developed a terrestrial life cycle.…”

“…Given the ubiquitous nature of oligochaetes and their obvious physical and physiological attributes that are reminiscent of many helminths (Stunkard, 1937(Stunkard, , 1940Goodchild, 1951), it is surprising that more oligochaete worms (Annelida: Clitellata) have not adopted an endoparasitic lifestyle. Indeed, endosymbiotic oligochaetes are rare, being restricted to 2 genera in the Naididae (Gelder, 1980).…”