An ultrastructural comparative study of the sperm of Hyla pseudopseudis, Scinax rostratus, and S. squalirostris (Amphibia: Anura: Hylidae)

Abstract

We make detailed comparisons of the ultrastructure of the spermatozoon among three species of the family Hylidae, Hyla pseudopseudis, Scinax rostratus, and S. squalirostris. The acrosome complex consists of two conical structures covering the nuclear rostrum, the acrosome vesicle, and the subacrosomal cone. The nucleus has a moderately condensed chromatin with a conical shape in longitudinal sections and a circular shape in cross-sections. In H. pseudopseudis, mitochondria are numerous and circular, and in S. rostratus and S. squalirostris there are fewer mitochondria that are more elongate in longitudinal and transverse sections. In H. pseudopseudis, the mitochondrial collar starts adjacent to the distal centriole, occupying the whole midpiece, whereas in both Scinax species the mitochondrial collar starts only at the posterior one-third of the midpiece. In both Scinax species, the presence of juxta-axonemal fiber, axial sheath, and axial fiber in the tail are seemingly plesiomorphic characters, widespread among bufonoid frogs. In H. pseudopseudis, however, the absence of axial fiber and axial sheath seems to be derived from the typical bufonoid condition. The differences between Hyla and Scinax sperm endorse the separation of the two genera and suggest that sperm ultrastructure can be a useful tool to investigate relationships at the intrafamily level.

A comparative ultrastructural analysis of spermatozoa in Pleurodema (Anura, Leptodactylidae, Leiuperinae)

“…The acrosome complex of the spermatozoa in most species of Pleurodema is formed by a subacrosomal cone below the acrosome vesicle, similarly to that observed in most studied hyloid frogs. This configuration was observed in Batrachylidae (Pugin and Garrido, ), Bufonidae (Burgos and Fawcett, ; Rastogi et al, ; Lee and Jamieson, ; Meyer et al, ; Báo et al, ), Calyptocephalellidae (Pugin and Garrido, ), Dendrobatidae (Garda et al, ; Aguiar‐Jr et al, 2003, 2004; Veiga‐Menoncello et al, ), Hylidae (Rastogi et al, ; Lee and Kwon, ; Lee and Jamieson, ; Costa et al, ), other Leptodactylidae (Amaral et al, ; Scheltinga, ; Zieri et al, ; Santos et al, ), Microhylidae (Scheltinga et al, ), Myobatrachidae (Lee and Jamieson, ), and Rhinodermatidae (Pugin and Garrido, ). The subacrosomal cone was also observed in Ascaphidae (Jamieson et al, ), Leiopelmatidae (Scheltinga et al, ), Pelodytidae (Pugin‐Ríos, ), Megophryidae, and Pelobatidae (Scheltinga, ).…”

“…The ultrastructural features of the spermatozoid tail of the studied species of Pleurodema are also noticeably variable. In most hyloids, the typical tail arrangement includes an axoneme and evident accessory fibers (juxtaxonemal fiber + axial fiber) separated by a thin undulating membrane (Scheltinga, ; Costa et al, , as “Bufonoidea”). In Pleurodema , a striking variety of arrangements have been observed in the tail morphology.…”

Comparative analysis of the sperm ultrastructure of three species of Phyllomedusa (Anura, Hylidae)

“…2002b), the position and length of the mitochondrial collar (Meyer et al . 1997; Costa et al . 2004), the number and shape of mitochondria (Costa et al .…”

“…1997; Costa et al . 2004), the number and shape of mitochondria (Costa et al . 2004), and the arrangement of tail elements (Lee and Jamieson 1993; Meyer et al .…”

“…Few studies were made on Neotropical genera, including Pachymedusa (Rastogi et al . 1988) and Hyla (Pugin‐Rios and Garrido 1981; Costa et al . 2004).…”