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Item Redescription of sperm structure and ultrastructure of Trichogramma dendrolimi (Hymenoptera: Chalcidoidea: Trichogrammatidae)(Acta Zoologica, 2001-04) Lino-Neto, José; Dolder, HeidiTo verify the questionable description of sperm structure of Trichogramma dendrolimi, in relation to Chalcidoids, a reinvestigation was undertaken. The spermatozoa appear wavy along their entire length. A small acrosome, together with the anterior nuclear region, is surrounded by an extracellular sheath, from which filaments radiate. The nucleus is helicoidal and attached to the flagellum by a centriolar adjunct. The axoneme has the 9 + 9 + 2 microtubule arrangement pitched in a long helix, with the spiralling mitochondrial derivatives coiling around it. Therefore, the spermatozoa of T. dendrolimi are very similar to those of other chalcidoids and different from the first description. It is now possible to affirm that the helical sperm structures are an apomorphic homology for Trichogrammatidae as well as Eulophidae, Pteromalidae, Eurytomidae, Torymidae, Mymaridae and for some other chalcidoids, if not all.Item Sperm structure and ultrastructure of the Melittobia hawaiiensis, Perkins and M. australica, Girault (Chalcidoidea: Eulophidae)(Tissue and Cell, 2009-04) Lino-Neto, José; Brito, Pedro; Dolder, HeidiSpermatozoa morphology has, for some years, been used to help answer some phylogenetic questions for Hymenoptera. This is the second study describing spermatozoa morphology of an Eulophidae species in which important characteristics were observed. Melittobia spermatozoa are spiralled and measure approximately 270 μm in length. The head contains a small acrosome, apparently formed only by an acrosomal vesicle, which, together with the initial nuclear region, is surrounded by an extracellular sheath, from which innumerable filaments irradiate. The nucleus is helicoidal and completely filled with compact chromatin. A centriolar adjunct is observed at the nucleus–flagellum transition; it associates laterally with the nucleus and exhibits two small expansions, which reach around the centriole. In the flagellum there are two mitochondrial derivatives, which in cross-sections are asymmetric. In the derivative with the larger diameter, two distinct regions are observed, a small one, near the axoneme, with a clear “fissure” inside, and a larger region where the cristae occur. Both derivatives initiate at the nuclear base, but the larger diameter derivative finishes first, before the flagellum extremity. At the end of the axoneme, the accessory microtubules are the first to finish.Item Morphology of the male reproductive system and spermatozoa in Centris Fabricius, 1804 (Hymenoptera: Apidae, Centridini)(Micron, 2012-06) Gomes, Luiz Fernando; Badke, Juliana P.; Zama, Uyrá; Dolder, Heidi; Lino-Neto, JoséThe genera Centris and Epicharis constitute the Centridini and are widely distributed in the Neotropical region. Centris is also found in the southern portion of the Neartic region, although both genera are more abundant in the humid tropical regions. To describe the structure of the male reproductive system and spermatozoa, light and transmission electron microscopy were used. The male reproductive system of Centris sp. is formed by a pair of testes, a pair of deferent ducts, a pair of seminal vesicles, a pair of accessory glands and an ejaculatory duct connected to the external genitalia, the aedeagus. In this species, testes and the pre-vesicular deferens ducts as well as the seminal vesicles are encapsulated in a single conjunctive capsule, the scrotal membrane. Each testis consists of four testicular follicles, made up of cysts with up to 64 germinative cells. Histologically, the seminal vesicles are formed by a simple cylindrical epithelium, basal membrane and muscular tunic. The spermatozoa of Centris analis, C. fuscata, C. tarsata and Centris sp. are morphologically similar. They have two easily distinguishable regions: the head and flagellum. The head is formed by the two-layer acrosome, the linear nucleus and the flagellum, the centriole adjunct, the axoneme of pattern 9 + 9 + 2 microtubules, two asymmetric mitochondrial derivatives and two accessory bodies. These Centris species share various morphological characteristics of the male reproductive system and spermatozoa with the other bees previously described, indicating that several characteristics are synapomorphic for the family Apidae. Studies on the morphology of the male reproductive system and spermatozoa in Hymenoptera have demonstrated the diversity of the information provided by these reproductive structures, which can be used in taxonomy studies and the phylogeny of this important group of insects.Item Sperm morphology of Muscidifurax uniraptor (Hymenoptera: Chalcidoidea: Pteromalidae)(Arthropod Structure & Development, 2016-05) Santos, Helen Pinto; Barcellos, Marcelo Silva; Reis, Aline Beatriz; Dolder, Heidi; Lino-Neto, JoséSperm morphology of the parasitoid Muscidifurax uniraptor was investigated under light and transmission electron microscopy. M. uniraptor sperm are filiform, spiraled, approximately 150 μm in length, with a distinctive head, hooded by an extracellular sheath and a flagellum. This extracellular layer, from which many filaments radiate, measures approximately 90 nm in thickness and covers a small acrosome and the anterior nuclear region. The acrosome is composed of an acrosomal vesicle and a perforatorium with its base inserted in the nuclear tip. The nucleus is filled with homogeneously compacted chromatin. The centriolar adjunct extends towards the anterior portion in a spiral around the nucleus for 3.5 μm in length. The two mitochondrial derivatives begin exactly at the centriole adjunct base and, in cross-section, have a circular shape with equal areas that are smaller than the axoneme diameter. It is coiled, with 9 + 9 + 2 microtubules and begins from the centriole, just below the nuclear base. The axoneme is connected to the mitochondrial derivatives by two small irregularly shaped masses. Between the derivatives and the axoneme, the ‘center-flagellar material’ is observed. Overall, these characteristics are recognized in other Chalcidoidea, especially in the eurytomids, but together they form a set of species-specific data.Item Morphology of spermatozoa of Dissomphalus connubialis (Ashmead, 1893) (Hymenoptera: Bethylidae)(Micron, 2012-07-17) Oliveira, Claudia Miranda de; Fraga, Felipe Bertholdi; Brito, Pedro; Gomes, Luiz Fernando; Dolder, Heidi; Lino-Neto, JoséIn this study, the morphology of spermatozoa of Bethylidae Dissomphalus connubialis (Pristocerinae) was analyzed using light and transmission electron microscopy. Spermatozoa of this species are thin, measure approximately 130 μm in length and comprise a head region and flagellum region. The head is formed by the acrosome and nucleus. The acrosome consists of the acrosome vesicle and the perforatorium, the posterior portion of which is inserted into a cavity at the anterior extremity of the nucleus. The nucleus is compact, electron-dense and measures 15 μm in length. The flagellum possesses two mitochondrial derivatives, two accessory bodies and one axoneme with a 9+9+2 microtubular pattern. The nucleus is connected to the flagellum by the centriole adjunct. Mitochondrial derivatives are compact, apparently without paracrystalline material and with rare mitochondrial cristae. They are asymmetric in length, such that the larger mitochondrial derivative begins parallel to the posterior region of the nucleus and the smaller mitochondrial derivative begins just below the centriole adjunct. The basic structure of spermatozoa of D. connubialis is similar to that of other Aculeata studied. However, this species shows characteristics not seen in other Hymenoptera, such as the wide electron-lucid region that separates the acrosomal vesicle from the perforatorium and the depth of the cavity in the anterior extremity of the nucleus, into which the base of the perforatorium is inserted. There are also characteristics that distinguish this species from Bethylidae Prorops nasuta, including the fact that one of the mitochondrial derivatives lies to parallel to the nucleus over a long distance, the small quantity of cristae, the absence of paracrystalline material in these organelles, and the fact that the accessory microtubules are the first to terminate in the final portion of the flagellum.