Paurorhynchus hiodontis, a New Genus and Species of Trematoda (Bucephalidae: Paurorhynchinae n. subfam.) from the Mooneye Fish, Hiodon tergisus

What is hidden under an eggshell? Ultrastructural evidence on morphology of “passive” Prosorhynchus squamatus miracidium (Digenea: Bucephalidae)

“…Its function seems to be distributed among two structures: the hypodermal cyton and the apical gland associated with the stylet. The stylet was previously described for bucephaloid larvae (Willemoes-Suhm, 1873, Dickerman, 1954, Suloeva, 1999. Presence of the stylet was also documented for miracidia of Sanguinicolidae (Tang, Ling, 1975;Simon-Martin et al, 1987), Encyclometridae (Ginetsinskaya, 1968) and Brachylaymidae (Lewis, 1969).…”

“…ciliated rods and spines on the surface of the larvae (e.g. Baylis, 1938;Allison, 1943;Dickerman, 1954). All of these schemes reflect simplified morphology of these tiny organisms.…”

Dollfustrema durum n. sp. and Heterobucephalopsis perardua n. sp. (Digenea: Bucephalidae) from the giant moray eel, Gymnothorax javanicus (Bleeker) (Anguilliformes: Muraenidae), and proposal of the Heterobucephalopsinae n. subfam

“…6), and in inhabiting the intestine of fishes. In contrast, the Paurorhynchinae lack a seminal duct, possess a rhynchus that is a small and weakly developed pad, and has members that occur within the swim bladder and/or body cavity of their host [41]. From the Macrorchirhynchinae Bilqees, Ibrahim, Khan, Ajazuddin & Talat, 2010, for which we do not have molecular data, the new material differs in the combined possession of a spinose body surface, the rhynchus lacking papilla, the pharynx situated anterior to the testes, and the testes in the posterior half of the body.…”

“…The embedding of Paurorhynchus (albeit based on a single sequence) within the Bucephalinae is interesting, but not surprising. The subfamily is biologically unique, occurring in the swim bladder, body cavity, and/or stomach of the host [41]. We suggest that the distinctive morphology of this group, which includes a small rhynchus, a mouth that opens in the anterior third of the body, lobed testes positioned in the posterior two-fifths of the body, the cirrus-sac only half as long as the posterior testis, a short pars prostatica, an ovary variable in shape and number of lobes, and vitelline follicles in linear series [41], arose in association with an ecological shift.…”