Scheltinga, D.M., Jamieson, B.G.M.
and McDonald, K.R.
2002b. Ultrastructure of the spermatozoa of Litoria
(Hylidae, Anura, Amphibia): modifications for penetration of a
gelatinous layer surrounding the arboreal egg clutch. Memoirs of the
Queensland Museum 48, 215-220.
Spermatozoa of Litoria
longirostris are
highly modified for its unique mode of fertilisation and differ
distinctively
from the sperm of the 10 Litoria species previously examined.spermatozoa are longer in head,
tail and total. The head is long and
straight
with a distinct acrosome vesicle compared to a short curved hea L.
longirostris
d in
other
Litoria spermatozoa. The
acrosome vesicle is well developed and
surrounds
approximately the apical third of the perforatorium only. The
perforatorium is
a solid homogenous rod that attaches to the nucleus asymmetrically
along one side.
The nucleus and midpiece are similar in size and structure to those of
other
Litoria species. The axial
fibre is greatly enlarged and a
juxta-axonemal fibre
at doublet 3, usual in anuran sperm, is absent. Although the
spermatozoa of L.
longirostris are highly modified, having secondarily lost the
bufonoid
synapomorphy of a putative conical perforatorium consisting of fibres,
it can
still be distinguished as a eubufonoid by the mitochondrial collar.
Thus, we
assert that sperm morphology is correlated with phylogenetic
relationships as
well as mode of fertilisation and that spermatozoal morphology can
provide
useful information in resolving phylogenetic relationships.