Ultrastructure of the accessory glands of the Mediterranean flour moth

Abstract

Five regions are recognized in the accessory glands of the Mediterranean flour moth, Anagasta kuehniella (Zeller), on the basis of cellular morphology and aggregates of secretory material in the lumen. Some variation is found in each of the posterior four regions, especially the third one. In the most anterior region (region 1) the epithelium is composed of a single type of cell, while in each of the other regions there are two classes of cells. The cells of region 1 and one class in each of the other four regions are fairly typical exocrine cells with extensive rough endoplasmic reticula. Secretion is primarily via Golgi-derived vesicles. Apocrine secretion in the form of sloughing off of the apical cytoplasm probably also occurs in all regions but is most prominent in the posterior two regions. One class of cells is very similar in morphology in each of the posterior four regions though their secretory products form characteristic aggregates in the lumen. The second class of cells (foliate cells) occurring in the posterior four segments is most notably characterized by elongate apical projections that extend out into the lumen. The apical projections contain large quantities of glycogen, some microtubules, and, in some cases, many minute mitochondria. The membrane content of the projections is also very high. In the anterior regions, the membranes are mostly fused in pairs and typically form multilayered whorls. Fusion and whorl formation decrease in the posterior regions. The cytoplasm of the foliate cells has a high organelle content including many lysosomes and mitochondria. The latter exhibit considerable polymorphism, with particular forms occurring in the different regions of the glands. The apical projections of the foliate cells are detached during copulation, presumably as the result of nervous stimulation, and become a part of the ejaculate. Replenishment of all secretory material, including the apical projections, occurs after copulation.

Structure of the male reproductive accessory glands ofPterostichus nigrita(Coleoptera: Carabidae), their role in spermatophore formation

“…Bairati 1968;Adiyodi and Adiyodi 1974;Dapples et al 1974;Gadzama et al 1977;Ramalingam and Craig 1978;Cassier and Huignard 1979;Riemann and Thorson 1979;Grimes and Happ 1980;Couche and Gillot 1990;Kaulenas 1992;Dallai et al 1997Dallai et al , 2012Cruz Landim and Dallacqua 2005;Fernandez and Cruz-Landim 2005;Freitas et al 2007;Marchini et al 2009;Freitas et al 2010; this study). Freitas et al (2007) suggested that basal infolding of the plasma membranes of cells indicated that they are absorbing substances from the hemolymph.…”

“…Tongu et al 1972;Dapples et al 1974;Ramalingam and Craig 1978;Riemann and Thorson 1979), we fixed small portions of tissue for TEM from two regions of the glands, hereinafter referred to as the distal and proximal (furthest and closest to joining the vas deferens, respectively) regions ( Figure 1). In addition, we also fixed tissues from the posterior vas deferens because this region of the male reproductive system had a glandular appearance ( Figure 1).…”

“…Those of L. decemlineata (De Loof and Lagasse 1972), Periplaneta americana (Adiyodi and Adiyodi 1974), Tenebrio molitor (Gadzama et al 1977;, and Frankiniella occidentalis (Dallai et al 1997) have one type only. By contrast, the tubular accessory glands of other male insects can be divided into distinct regions, each region with a different type of secretory cell and/or secretion (Ramalingam and Craig 1978;Riemann and Thorson 1979;Lai-Fook 1982;Marchini et al 2009). Two morphological types of epithelial cells were found in the male accessory glands of P. nigrita, one with a cytoplasm full of secretory droplets and an apical plasma membrane lacking microvilli (type 1 cells), and a second type (type 2 cells) lacking secretory droplets but with well-developed microvilli.…”

“…Studies on the structure of the accessory glands of male insects have shown that the glands not only vary in size, shape, and number between species, but also in the morphology of their epithelial cells and types of secretions within the glands (Odhiambo 1969a,b;De Loof and Lagasse 1972;Tongu et al 1972;Leopold 1976;Riemann and Thorson 1979;Lai-Fook 1982;Chen 1984;Davey 1985;Happ 1992;Dallai et al 1999;Sukontason et al 2009). Although secretory product variability exists between species, most produce a secretion rich in proteins and peptides (Leopold 1976;Davey 1985;Happ 1992;Wolfner 1997;Gillott 2003;Marchini et al 2009).…”

Morphostructural analysis of the male reproductive system and DNA barcoding in Balclutha brevis Lindberg 1954 (Homoptera, Cicadellidae)

“…It should be noticed, in this regard, that despite a holocrine-type secretion way has been hypothesized in the male accessory glands of other insects (Chen, 1984;Perotti, 1971;Riemann and Thorson, 1979), this finding has not been found in the Homoptera until now.…”