Abstract: Abstract: 【Aim】 Sperm ultrastructure has great importance for species recognition and phylogenetics of insects. Studying sperm ultrastructure in the Fulgoroidea can provide more evidence towards phylogenetic analysis which, so far, remains controversial. 【Methods】Both the spermatozoon morphology and the ultrastructure of Euricania clara Kato were observed by ultramicrotomy in combination with light and transmission electron microscopy.【Results】 Mature spermatozoa of E. clara form a sperm bundle called spermatodesm, and each individual spermatozoon has no polymorphism and consists of a head, neck and long flagellum. The head includes the apical bilayered acrosome and nucleus. The neck region is comprised of a centriole and centriolar adjunct. The long flagellum mainly consists of a pair of symmetrical D-shaped mitochondrial derivatives, a pair of fishhook-shaped accessory bodies, and axoneme with the typical 9+9+2 microtubule pattern. 【Conclusion】The characteristics of fish-hook shaped accessory bodies of E. clara are generally consistent with those of other fulgoroids known to date, but are significantly different from other auchenorrhynchans. Furthermore, the number, size, and cross-section morphology and composition of spermatozoic mitochondrial derivatives of E. clara differ significantly from those of other insects. Although there is some consistency within the suborder Auchenorrhyncha, there are obvious differences. This study provides scientific data for phylogenetic analysis of the Fulgoroidea.

Key words: Auchenorrhyncha; Ricaniidae, Euricania clara, sperm, ultrastructure, mitochondrial derivative, accessory body