Structural specialization in the flagellum of the spermatozoon of the bloodsucking bug (Rhodnius prolixus; Hemiptera, Reduviidae)

Abstract

Spermatozoa of the triatomideo Rhodnius prolixus possess an axoneme with a 9 + 9 + 2 microtubule pattern and two mitochondrial derivatives. Bridges occur between axoneme and mitochondrial derivatives. Two paracrystalline structures embedded in amorphous regions were observed in the mitochondrial derivative. The use of the negative staining technique shows a zig-zag profile in the mitochondrial derivatives due to infolding to the cristae, regularly spaced with approximately 50 nm. This spacing is also observed in the distribution of the strands of particles in the mitochondrial membrana as seen in freeze-fracture replicas. In the P-fracture face of the flagellar plasma membrane, a regular array of the intramembranous particles was observed. This array consists of two rows, with 12-15 particles, and occurs in the space between the mitochondrial derivatives. Thus R. prolixus spermatozoon present a membrane domain, localized in the flagellar region, and bridges between mitochondrial membrane derivatives and the plasma membrane are probably attached to the flagellar components. These membrane specializations may be related to the production of coordinated flagellar movement, and can contribute significantly to further phylogenetic studies.

Ultrastructure and heteromorphism of spermatozoa in five species of bugs (Pentatomidae: Heteroptera)

“…The loss of accessory bodies was also observed in species of Nepomorpha (Lee, 1991;Lee and Lee, 1992), Cimicomorpha, Reduviidae (Báo and DeSouza, 1994) and Auchenorrhyncha (Chawanji et al, 2005(Chawanji et al, , 2006. The accessory bodies are possibly a homoplastic characteristic in Hemiptera, considering that the presence and absence of this structure have already been reported in the suborders, Auchenorrhyncha and Heteroptera.…”

“…Among the Heteroptera, the ultrastructure of spermatozoa has been described in species of Pentatomidae (Trandaburu, 1973;Fernandes and Báo, 1998), Reduviidae (Dolder, 1988;Báo and DeSouza, 1994), aquatic Heteroptera (Afzelius et al, 1985;Lee, 1991;Lee and Lee, 1992), Leptopodomorpha , Cimicomorpha, Gerromorpha, and Pentatomomorpha (Dallai and Afzelius, 1980). These works revealed the presence of two or three crystalline bodies in mitochondrial derivatives as a synapomorphy for Heteroptera.…”

“…In Hemiptera, studies on spermatozoa ultrastructure are rare and restricted to some species (Danilova et al, 1983;Báo and DeSouza, 1994;Carcupino et al, 1998;Chawanji et al, 2005Chawanji et al, , 2006Chawanji et al, , 2007Araújo et al, in press, 2010). The production of polymorphic spermatozoa has been reported in some Pentatomidae (Bowen, 1922;Schrader and Leuchtenberger, 1950), Largidae (Araújo et al, in press), and Cicadidae (Kubo-Irie et al, 2003;Chawanji et al, 2005Chawanji et al, , 2006.…”

Contribution of the golgi Complex—Endoplasmic reticulum system during spermiogenesis in three species of phytophagous bugs (Hemiptera : Pentatomidae)

“…Heteropteran spermatozoa have common characteristics, which are not found in other insects : 2-3 crystalline bodies within the mitochondrial derivatives and bridges between the mitochondrial derivatives and 2 of the axonemal microtubules (Afzelius et al, 1976;Afzelius et al, 1985;Dallai and Afzelius, 1980;Dolder, 1988;Báo and de Souza, 1994a). But, like other insects, the heteropteran spermatozoa possess a head containing nucleus and acrosome, and the tail, which, contains axoneme and mitochondrial derivatives.…”

“…Heteropteran spermatozoa have certain characteristics in common that are not found in other insects : 2-3 crystalline bodies within the mitochondrial derivatives and bridges between the mitochondrial derivatives and 2 of the axonemal microtubular doublets (Afzelius et al, 1976;Dallai and Afzelius, 1980;Dolder, 1988;Báo and de Souza, 1994a).…”