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.