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Item Sperm bundles in the seminal vesicle of the crematogaster victima (Smith) adult males (Hymenoptera: Formicidae)(Neotropical Entomology, 2014-06) Oliveira, C. M.; Lino-Neto, J.; Moreira, J.; Gomes, L. F.; Camargo-Mathias, M. I.This study establishes the presence of spermatodesm in the seminal vesicles of sexually mature males of Crematogaster victima (Smith). In this species, the spermatozoa are maintained together by an extracellular matrix in which the acrosomal regions are embedded. This characteristic has not yet been observed in any other Aculeata. However, the sperm morphology in this species is similar to that described for other ants. The spermatozoa measure on average 100 μm in length, and the number of sperm per bundle is up to 256. They are composed of a head formed by the acrosome and nucleus; this is followed by the flagellum, which is formed by the centriolar adjunct, an axoneme with a 9 + 9 + 2 microtubule pattern, two mitochondrial derivatives, and two accessory bodies. The acrosome is formed by the acrosomal vesicle and perforatorium. The nucleus is filled with compact chromatin with many areas of thick and non-compacted filaments. Both mitochondrial derivatives have the same shape and diameters. The presence of sperm bundles in sexually mature males differentiates C. victima from other ants; however, the similarities in the sperm ultrastructure support the monophyly of this insect group.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 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.