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The morphology and ultrastructure of female accessory reproductive glands of Anopheles maculipennis s.s., Anopheles labranchiae and Anopheles stephensi were investigated by light and electron microscopy. The reproductive system in these species is characterized by two ovaries, two lateral oviducts, a single spermatheca and a single accessory gland. The gland is globular and has a thin duct which empties into the vagina, near the opening of the spermathecal duct. Significant growth of the accessory reproductive gland is observed immediately after blood meal, but not at subsequent digestion steps. At ultrastructural level, the gland consists of functional glandular units belonging to type 3 ectodermal glands. The secretory cells are elongated and goblet shaped, with most of their cytoplasm and large nucleus in the basal part, close to the basement lamella. Finely fibrous electron-transparent material occupies the secretory cavity that is in contact with the end of a short efferent duct (ductule) emerging from the gland duct. The present study is the first detailed description of female accessory gland ultrastructure in Anophelinae and provides insights into the gland's functional role in the reproductive biology of these insects., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Sperm structure of four Systellognatha species, Dinocras cephalotes (Curtis, 1827) and Perla grandis (Rambur, 1841), family Perlidae, Siphonoperla torrentium (Pictet, 1841), family Chloroperlidae, and Isoperla grammatica (Poda, 1761), family Perlodidae, was investigated by light microscopy, scanning and transmission electron microscopy, and immunofluorescence microscopy. The spermatozoa of all the species are filiform and flagellate; they have an elongated compact nucleus, topped by either a bi-layered or three-layered acrosomal complex, and a '9+9+2' axoneme flanked by two mitochondrial derivatives. However, some variations have been observed, particularly regarding the morphology of the acrosomal complex, the shape of the nucleus, two more or less evident accessory bodies flanking the axoneme and the degree of crystallisation of the mitochondrial derivatives. Our results support the suggestion that Systellognatha is a monophyletic group, showing a single sperm pattern. Chloroperlidae and Perlodidae retain the plesiomorphic condition of some sperm characters while Perlidae show some autoapomorphies. A phylogenetic affinity between Plecoptera and the other orders of Polyneoptera has been confirmed.

The ultrastructure of spermatozoa of four Plecoptera species, Leuctra fusca Linnaeus, Brachyptera risi (Morton), Taeniopteryx stankovitchi Ikonomov, T. kuehtreiberi (Aubert), was investigated by light microscopy, scanning and transmission electron microscopy, and immunofluorescence microscopy. The spermatozoa of all the species have a complex acrosome, are filiform and flagellate, with a '9+9+2' axoneme flanked by two mitochondrial derivatives. However, the structure shows a certain interspecific heterogeneity. L. fusca has a short conical nucleus in the apical position and an axoneme flanked by two accessory bodies. In the sperm of the Taeniopterygidae, the nucleus is a long cylindrical body which lies between the two mitochondrial derivatives flanking the axoneme for most of its length. Our results suggest a close phylogenetic affinity between Plecoptera and the other orders of Polyneoptera, although the proposed sister-group relationship between Plecoptera and Embioptera cannot be confirmed.