Lee, M.S.Y. and Jamieson, B.G.M. 1992g. The
ultrastructure of the spermatozoa of three species of myobatrachid
frogs (Anura, Amphibia) with phylogenetic considerations. Acta
Zoologica (Stockholm) 73, 213-222.
Comparison of the spermatozoa of three
genera of limnodynastines (Myobatrachidae: Anura) with those of 42
species of frogs (in 11 families) previously examined allows the
phylogenetic inferences. The bufonoid neobatrachians (corresponding
Arcifera of some classifications) form a monophyletic assemblage which
characterized by the possession, unique for the Anura, of a conical
perforatorium; the rod-like perforatorium, which is plesiomorphic for
tetrapods, is absent. Of the taxa investigated, the myobatrachids
appear to be
the sister-group of the remaining bufonoids, here termed eubufonoids
(leptodactylids, rhinodermatids, hylids, and bufonids). The spermatozoa
myobatrachids Limnodynastes, Neobatrachus, and Mixophyes are very
each other despite extremely varied fertilization biology.
for the Anura which they exhibit include the conical acrosome with
material, the elongate, cylindrical nucleus, single flagellum and,
this, an undulating membrane which is supported by a longitudinal
axial (major) fibre, the latter being accompanied in the midpiece by
mitochondria. A myobatrachid synapomorphy appears to be the presence of
periaxial sheath enclosing the axial fibre of the flagellum. Forward
of the axial fibre into the centriolar fossa in myobatrachids is seen
only exceptionally (in the bufonid Nectrophynides).
Bufonids, and most
eubufonoids including leptodactylids, differ apomoprhically from
and Neobatrachus in location
of the mitochondria at the axonemal end
(and in a
collar) rather than the axial fibre end of the undulating membrane. In
surround the nuclear-axonemal junction in a
droplet and are probably shed with this at maturity.