In this study, we evaluated the possible role of Ligia italica as a bioindicator for the monitoring of heavy metals pollution in the suppralittoral zone of marine rocky coasts. Between 2004 and 2011 specimens of L. italica were collected along the Eastern Sicilian coasts from sites known for their high pollution levels as they are near to an area where in September 2001 a refinery plant discharged into the sea some waste containing Hg. Other specimens were collected from the Vendicari Natural Reserve located about 30 miles from the polluted sites and used as control area. On a consistent number of animals, the concentration in toto of As, Cd, Cr, Hg, Ni, Pb, V, was determined by Atomic Absorption Spectrometry. On other animals, investigations were carried out in order to check for ultrastructural alterations of the hepatopancreas, that is the main metals storage organ in isopods. Results revealed the presence, in the animals collected in 2004 from the polluted sites, of considerable concentrations of Hg and of lower concentrations of other metals such as As, Pb and V. The Hg bioaccumulation resulted in remarkable ultrastructural alterations of the two cellular types (B and S cells) in the epithelium of the hepatopancreas. Surprisingly, a moderate amount of Hg was also found in specimens collected in 2004 from the Vendicari Natural Reserve, proving that the Hg pollution can also spread many miles away. Animals collected from the polluted sites in the following years showed a progressively decreasing Hg content, reaching very low levels in those from the last sampling. Also, the ultrastructural alterations found in the hepatopancreas of the animals from the last sample were quite irrelevant. In conclusion, Ligia italica can represent a good bioindicator and the ultrastructure of the hepatopancreas could be used as ultrastructural biomarker of heavy metals pollution in the supralittoral zones.

A morphological and ultrastructural study of the spermatheca of some species of Orthoptera Tettigoniidae was carried out to understand the role of this female organ in the reproductive biology because no literature exists about it in this insect group. In all the examined species, the spermatheca is of ectodermal origin and is composed of a seminal receptacle, mainly involved in the collection and storage of the spermatozoa, and of a spermathecal duct. In both these organs, the epithelium of the wall is made up of two different cell types: cuticle-forming cells, underlying the cuticular intima, and gland cells. Both of these cell types have secretory features that differ among the species and also within the same species, in relation to the tracts examined. In particular, the ultrastructure of the distal tract of the spermathecal duct indicates a more marked secretory activity than in the other tracts of the duct. This activity is often accompanied by ultrastructural aspects, suggesting a lysis activity in both the epithelium and the upper cuticle. Based on these findings, it is hypothesized that the seminal receptacle and the spermathecal duct have different functional roles, despite having a similar general structural organization.

The aim of this study was to evaluate the efficacy of sperm storage in the seminal receptacle in females of Armadillidium granulatum after the first mating and in the absence of further mating. Females of A. granulatum were bred in the laboratory, isolated from males, until they were sexually mature, and then they were allowed to mate. They were then isolated again from the males and observed to evaluate their reproductive behaviour until their natural death. Some females were sacrificed at various time intervals to carry out ultrastructural observations of the seminal receptacle and of the spermatozoa inside. All the females had the first brood at about 20 days after mating; a little less than 50% of the females had a second brood during the first reproductive season; only 10% of the females had another brood during the second reproductive season. The average number of juveniles produced by each female was about 25 at the first brood, but fall with the successive broods; the sex ratio of juveniles was about 1 male : 4 females. The ultrastructural observations showed some variations in the seminal receptacle wall over time with respect to reproductive activity while there was no appreciable modification as regards the spermatozoa present in the organ, the number of which progressively decreased during the period of reproductive activity.

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In females of Isopoda Oniscidea, the genital system displays a remarkable variability of its morphological and functional organization as possible adaptation to different strategies of sperm storage. In all the oniscidean species, the sperm received from the male during mating are temporarily stored in the bursa copulatrix, a chitinous pouch of the oviduct. In 27 of the 32 species we studied, the sperm that remain in the bursa copulatrix after the fertilization of eggs of the first oviposition are transferred into the seminal receptacle, where they can be stored for a variable time. In these species, the seminal receptacle is a small kidney-shaped cup, localized at the insertion of the oviduct into the ovary. Only in two species of the genus Trichoniscus, in which the oviduct is very short, is the bursa copulatrix modified to form a large lateral diverticle.Instead, in three species of the family Halophilosciidae, Halophiloscia couchii, Halophiloscia hirsuta and Stenophiloscia glarearum, the ovary is consistently shorter, while the seminal receptacle is greater; after mating, both seminal receptacle and ovary appear completely filled with sperm. Finally, in two species of the family Tylidae, Tylos europaeus and Helleria brevicornis, the female genital system lacks specialized structures for sperm storage, and every oviposition requires a mating for the eggs fertilization.The authors present some hypotheses to explain the variability of the female genital system morphology and the sperm storage strategies.