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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 sperm ultrastructure of Leucoptera coffeella (Lepidoptera: Lyonetiidae)(Acta Zoologica, 2006-05-09) Lino-Neto, J.; Alves, L.; Mancini, K.; Dolder, H.The male reproductive tract of Leucoptera coffeella was processed for light and transmission electron microscopy. In the testis, the eupyrene cells are arranged in individual cysts, while the apyrene cysts form aggregates, never observed in other Lepidoptera. Both cysts contain 128 spermatozoa, which differ from the typical pattern. In the seminal vesicle, both types of spermatozoa are dispersed in the lumen, also different from other Lepidoptera. The apyrene spermatozoa are similar to those observed for other Lepidoptera. They present an anterior region covered by a dense cap and the flagellum is composed of a 9 + 9 + 2 axoneme and two mitochondrial derivatives. The eupyrene spermatozoa, however, differ from the typical pattern for Lepidoptera. Their anterior region contains a nucleus, an acrosome and a peculiar arc of eight accessory microtubules connected to the plasma membrane by dense bridges. In the nucleus–flagellum region, the ninth accessory microtubule is assembled between both mitochondrial derivatives, to participate in the axoneme. The flagellum comprises a 9 + 9 + 2 axoneme and two mitochondrial derivatives with paracrystalline cores. External to the plasma membrane and close to the accessory microtubules, there are tufts of an amorphous material, suggesting reduced lacinate appendages, while the reticular ones are absent. The reduction of lacinate appendages and the absence of sperm bundles in the seminal vesicle support the concept that the appendages of other Lepidoptera could be associated with the eupyrene aggregations. The characters ‘number of spermatozoa per cyst’ and ‘absence of bundles’ should be considered plesiomorphic, supporting the position of this taxon in the base of the Ditrysia.Item The rectum of Oxaea flavescens (Andrenidae) has a specialized structure among bees(Micron, 2003-11-10) Serrão, José Eduardo; Marques-Silva, Solange; Martins, Gustavo FerreiraThe rectum of the bee Oxaea flavescens contains six hollow rectal papillae, in contrast to rectal pads found in others Hymenoptera. The rectal epithelium is formed by cubical cells with structural specializations for fluid transport, such as apical plasma membrane invaginations, endocytic vesicles, scalariform junctions, wide extracellular space and double-membrane vesicles. Globular-shaped cells form the rectal papillae with surface plasma membrane invaginations that vary from small depressions to very large sinuses. The cell–cell contact is narrow, exhibiting extensive regions with scalariform junction, while cytoplasmic free ribosome-like material is prominent. These ultrastructural features are discussed in relation to their role in excretion in this bee.Item Sperm ultrastructure of the honey bee (Apis mellifera) (L) (Hymenoptera, Apidae) with emphasis on the nucleus-flagellum transition region(Tissue and Cell, 2000-05-26) Lino-Neto, J.; Báo, S.N.; Dolder, H.The flagellum of Apis mellifera (Hymenoptera, Apidae) consists of two mitochondrial derivatives, an axoneme and two accessory bodies. The mitochondrial derivatives are of unequal size and lie parallel to the axoneme. In the larger derivative four regions can be distinguished while in the smaller, only three. The region occurring only in the larger derivative consists of paracystalline material. The smaller mitochondrial derivative terminates anterior to the larger one. An extremely long centriolar adjunct is observed between the nucleus and the smaller mitochondrial derivative. This adjunct is compact, very electron dense and gradually tapers from base toward apex, finishing at the anterior extremity of the axonemal microtubules. In this flagellar region, there is only one accessory body present between the larger mitochondrial derivative and the axoneme. Anteriorly, the tips of the axonemal microtubules are inserted in a well developed mass of granular appearance. This material surrounds the nuclear base, separating it from the anterior end of the larger mitochondrial derivative. We believe that the structure identified here as a centriolar adjunct is homologous to that observed in Formicidae, Ichneumonoidea and Symphyta. Therefore, very probably, it is common to most Hymenoptera.Item Sperm structure and ultrastructure of the fire ant Solenopsis invicta (Buren) (Hymenoptera, Formicidae)(Tissue and Cell, 2002-03-22) Lino-Neto, José; Dolder, HThe spermatozoa of Solenopsis invicta are long and slender, measuring about 70 μm in length, of which the head region measures approximately 13 μm. The head consists of an acrosome formed by an acrosomal vesicle covering a perforatorium and a nucleus. This latter measures about 12 μm, has compact chromatin, and many translucent areas. The flagellum consists of an axoneme of 9+9+2 microtubules that begins just below the nuclear base. The two mitochondrial derivatives are of almost equal diameter, and there are two accessory bodies. The nucleus is attached to the flagellum by a centriolar adjunct located between the baso-lateral region of the nucleus and the anterior mitochondrial derivative extremities. Therefore, the nucleus–flagellum transition region of the spermatozoa of S. invicta is very similar to that of other ants and differs from the first description of this species [Ann. Entomol. Soc. Am. 67 (1967) 632]. In relation to other aculeates, it is possible that three characteristics (type of centriolar adjunct, presence of paracrystalline areas in each mitochondrial derivative, and the position of these areas within each derivative) may be autopomorphies for the Formicidae.Item Ultrastructure of the midgut endocrine cells in Melipona quadrifasciata anthidioides (Hymenoptera, Apidae)(Brazilian Journal of Biology, 2003-11-30) Neves, C. A.; Gitirana, L. B; Serrão, J. E.In this study we describe the ultrastructure of the endocrine cells observed in the midgut of M. quadrifasciata anthidioides. This bee has two types of endocrine cells, which are numerous on the posterior midgut region. Cells of the closed type are smaller and have irregular secretory granules with lower electrondensity than those of the open cell type. The open cell type has elongated mitochondria mainly on the basal area, where most of the secretory granules are also found. Besides the secretion granules and mitochondria, endocrine cells in this species have well-developed autophagic vacuoles and Golgi complex elements.