Sperm ultrastructure of the wasp Agelaia vicina (Hymenoptera, Vespidae)

Abstract

The present research represents the first description of a Vespidae species spermatozoon. In Agelaia vicina, the sperm head is composed of an acrosome and a nucleus. The acrosome consists of an acrosomal vesicle, oval shaped in cross sections, and a perforatorium, that projects into the anterior nuclear region. The nucleus is elongated and oval shaped in cross sections. The nucleus-flagellum transition region includes the centriolar adjunct, the nucleus base and the anterior portions of the axoneme and of the large mitochondrial derivative. The centriolar adjunct begins as a thin layer between the nucleus and the large mitochondrial derivative, while just below it acquires a lateral extension partially surrounding the large mitochondrial derivative. In its medial portion, it is triangular shaped, situated laterally to the axoneme and the large mitochondrial derivative, and it finishes in contact with the tip of the small mitochondrial derivative. The flagellum is composed of a 9+9+2 axoneme, two mitochondrial derivatives and two accessory bodies. The large mitochondrial derivative begins laterally to the nuclear base, and the small one below the centriolar adjunct. Only the large mitochondrial derivative presents a paracrystalline core, situated distally in relation to the axoneme. In the posterior flagellar region, the small mitochondrial derivative finishes first, followed by the large one and both accessory bodies. Although Vespidae belong to the superfamily Vespoidea, as Formicidae, the sperm ultrastructure of A. vicina is phylogenetically more closely related to Apoidea, and curiously very different from that observed for ants. This study supports the use of insect sperm morphology as a tool for phylogenetic analysis, especially in the Hymenoptera order.

Morphology of the male reproductive system and spermiogenesis in Hypanthidium foveolatum (Alfken, 1930) (Hymenoptera: Apidae: Megachilinae)

“…The arrangement observed in the axoneme with 9 + 9 + 2 microtubules is the pattern for Aculeata with the central microtubules and the nine doublets terminating first, followed by the accessory microtubules (Lino-Neto et al, 2000b, Zama et al, 2001, Zama et al, 2004, Zama et al, 2005a, Zama et al, 2005b, Zama et al, 2007, Báo et al, 2004, Araújo et al, 2005, Fiorillo et al, 2005and Mancini et al, 2006. Based on the characteristics compared above, the spermatozoa of H. foveolatum are, for the most part, similar to the majority of the Hymenoptera ( Jamieson et al, 1999).…”

“…The nuclear base penetrating into the beginning of the axoneme has also been observed in Apinae (Peng et al, 1993 andLino-Neto et al, 2000b) and Vespidae (Mancini et al, 2006). However, it is uncommon for the vast majority of Apoidea, which have the nuclear base finishing in a short cone above the axonemal implantation (Zama et al, 2001, Zama et al, 2004, Zama et al, 2005a, Zama et al, 2005b, Báo et al, 2004and Fiorillo et al, 2005.…”

“…The asymmetry in length and diameter of the mitochondrial derivatives is common for most Apoidea (Lino-Neto et al, 2000b;Zama et al, 2001, Zama et al, 2004, Zama et al, 2005a, Zama et al, 2005b, Báo et al, 2004and Fiorillo et al, 2005, Vespidae (Mancini et al, 2006), and some Symphyta (Newman and Quicke, 1999a). Furthermore, the mitochondrial regions in H. foveolatum are very similar to those described for other Apoidea ( Lino-Neto et al, 2000b;Zama et al, 2001, Zama et al, 2004, Zama et al, 2005a, Zama et al, 2005b, Araújo et al, 2005and Fiorillo et al, 2005.…”

Morphology of testicular and post-testicular spermatozoa in Microstigmus arlei Richards, 1972 and M. nigrophthalmus Melo, 1992 (Hymenoptera: Apoidea: Pemphredoninae) with phylogenetic consideration

“…Vespidae it varies from 13 to 577 μm ( Quicke et al, 1992 andMancini et al, 2006) while in Apoidea, these measurements vary between 80 μm and 450 μm for sphecids ( Quicke et al, 1992 andZama et al, 2005b) and bees (e.g. Baer et al, 2003, Zama et al, 2004, Báo et al, 2004, Fiorillo et al, 2005aand Fiorillo et al, 2005b, except for Euglossini with 750 to 1.500 μm in length .…”

“…This nuclear insertion is displaced to one side (asymmetric) as we also observed in Microstigmus. Despite these exceptions, the acrosome in Hymenoptera is made up of an acrosomal vesicle and a perforatorium (bilayered pattern) ( Cruz-Höfling et al, 1970, Wheeler et al, 1990, Quicke et al, 1992, Newman and Quicke, 1999a, Lino-Neto and Dolder, 2001a, Lino-Neto and Dolder, 2002, Zama et al, 2001, Zama et al, 2004, Zama et al, 2005c, Báo et al, 2004, Badke et al, 2005, Fiorillo et al, 2005a, Fiorillo et al, 2005band Mancini et al, 2006 or includes an additional third layer, an extracellular sheath, which covers all the acrosomal vesicle and part of the nucleus ( Quicke et al, 1992, Newman and Quicke, 1998, Newman and Quicke, 1999b, Lino-Neto et al, 1999, Lino-Neto et al, 2000aand Lino-Neto and Dolder, 2001a. As a rule, the perforatorium is dense and compact, but in some bees ( Báo et al, 2004, Fiorillo et al, 2005a and in the Vespidae Agelaia vicina ( Mancini et al, 2006), it appears slightly paracrystalline.…”