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The sand boa Eryx jaculus (Linnaeus, 1758) is found in the southern Balkans, Middle East and North Africa (Sindaco et al., 2013). Only recently The presence of this species has been confirmed in Italy, in a small area of southern Sicily (Insacco et al., 2015). Knowledge of the sand boa in Sicily is limited with few data on geographical distribution, morphology, and habitat (Insacco et al., 2015; Faraone et al., 2017). Even at a global scale the biology of this species is little known due to its secretive habits (Tokar & Obst, 1993).

The Atlantic blue crab Callinectes sapidus Rathbun, 1896 is included among the worst invasive alien species in the Mediterranean Sea. Here, we report the finding of the species in two Sicilian rivers, the Irminio and the Imera Meridionale, where it was collected up to 6 km from the river mouths. Although several records of the species are already available from Italy, this is the first evidence of the occurrence of this invasive crab so far from the coastline in the whole country. In the light of the well-known impact of the Atlantic blue crab on the invaded water bodies, the monitoring of the species and appropriate mitigation strategies should be implemented in order to protect the threatened native biota of Sicilian inland waters.

Ambient vibration modal identification, also known as Operational Modal Analysis, aims to identify the modal properties of a structure based on vibration data collected when the structure is under its operating conditions, i.e., no initial excitation or known artificial excitation. This procedure for testing and/or monitoring historic buildings, is particularly attractive for civil engineers concerned with the safety of complex historic structures. However, since the external force is not recorded, the identification methods have to be more sophisticated and based on stochastic mechanics. In this context, this contribution will introduce an innovative ambient identification method based on applying the Hilbert Transform, to obtain the analytical representation of the system response in terms of the correlation function. In particular, it is worth stressing that the analytical signal is a complex representation of a time domain signal: the real part is the time domain signal itself, while the imaginary part is its Hilbert transform. A 3DOF numerical example will be presented to show the accuracy of the proposed procedure, and comparisons with data from other methods assess the reliability of the approach. Finally, the identification method will be extended to the real case study of the Chiaramonte Palace, a historic building located in Palermo and known as “Steri”.

The Javelin Sand Boa, Eryx jaculus, is reported to be a predator of mammals, lizards and their eggs, and occasionally of birds and invertebrates, but data on its diet are scarce and fragmentary. Here we describe some aspects of the feeding behavior of E. jaculus on the Mediterranean island of Sicily. A total of 132 individual snakes were examined. Prey remains were found in 43% of them, both in their feces (82.5%) and gut contents (17.5%). The number of snakes observed and their feeding rate decreased in August, probably as a result of the relatively higher temperatures. Feeding rate increases were observed in adult females in September, perhaps to enhance body reserves before hibernation. The overall prey spectrum is dominated by small mammals, with a frequency of occurrence of 71.4%, but also consisted of lizard eggs (30.2%) and lizards (7.9%). Lizards seem to be occasional prey, and our frequent detection of ingested autotomized tails suggests E. jaculus has low efficiency as a saurian predator. We observed a relationship between prey type and snout- vent length of the snakes. Lizard eggs are most frequently eaten by smaller snakes, which could be linked to gape size ontogenetic variation. We found differences in the prey spectrum between sexes and age classes. Our results indicate that juveniles, adult males, and females seem to adopt different foraging strategies. Females probably adopt ambush predation on small mammals, while juveniles are active foragers of lizard eggs. Adult males appear to be slightly more versatile predators, consuming both types of prey, probably because of their high mobility rates during the mating period.

The presence of the Javelin sand boa in Sicily has recently been confirmed. Here the morphological characters and sexual dimorphism of the Sicilian population of Eryx jaculus are presented. Seven meristic and six metric characters in 96 specimens from Sicily were examined. The results show that tail length, snout-vent length, the distance between nostrils and the number of ventral and subcaudal scales are different between sexes. The characters found in the Sicilian population of the Javelin sand boa resemble those of the African population (ssp. jaculus) rather than the Eurasian population (ssp. turcicus), but biomolecular studies are necessary to understand its taxonomic identity., Acta Herpetologica, Vol 14 No 2 (2019)