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Growth rate of a wild population of the Javelin Sand Boa, Eryx jaculus (Linnaeus, 1758): first evidence from a long-term study in Sicily, Italy
Full text linkOn the occurrence of Eudiaptomus gracilis (G.O. Sars, 1863) (Copepoda: Diaptomidae) in Madeira (Portugal)
Full text linkCalanoid copepods belonging to the diaptomid genus Eudiaptomus Kiefer, 1932 were collected in an artificial water body on the island of Madeira, Portugal. The morphological and molecular identification of the collected specimens unequivocally proved that they belong to the allochthonous species Eudiaptomus gracilis (G. O. Sars, 1863), possibly unwarily introduced along with fish stockings or ornamental aquatic plants. In the sampled site, the species co-occurred with the non-native cyclopoid copepod Acanthocyclops americanus (Marsh, 1893) and some anomopod species. This is the first record of the species for Portugal and the whole Macaronesia, whereas the possible presence of E. gracilis in the Iberian Peninsula should
be verified.Copépodos calanoides pertenecientes al género de diaptómido Eudiaptomus Kiefer, 1932 fueron recolectados en una masa de agua artificial en la isla de Madeira, Portugal. Las identificaciones morfológicas y moleculares de los especímenes recolectados demostraron inequívocamente que pertenecían a la especie alóctona Eudiaptomus gracilis (G. O. Sars, 1863), posiblemente introducida inadvertidamente con introducciones de peces o plantas acuáticas ornamentales. En la localidad muestreada, la especie coexistía con el copépodo ciclopoide no nativo Acanthocyclops americanus (Marsh, 1893) y algunas especies de anomopodos. Esta es la primera cita de la especie para Portugal y para Macaronesia, aunque la posible presencia de E. gracilis en la Península Ibérica necesita verificación
Molecular Cytogenetic Characterization of the Sicilian Endemic Pond Turtle Emys trinacris and the Yellow-Bellied Slider Trachemys scripta scripta (Testudines, Emydidae)
Full text linkTurtles, a speciose group consisting of more than 300 species, demonstrate karyotypes with
diploid chromosome numbers ranging from 2n = 26 to 2n = 68. However, cytogenetic analyses have
been conducted only to 1/3rd of the turtle species, often limited to conventional staining methods.
In order to expand our knowledge of the karyotype evolution in turtles, we examined the topology of
the (TTAGGG)n telomeric repeats and the rDNA loci by fluorescence in situ hybridization (FISH)
on the karyotypes of two emydids: the Sicilian pond turtle, Emys trinacris, and the yellow-bellied
slider, Trachemys scripta scripta (family Emydidae). Furthermore, AT-rich and GC-rich chromosome
regions were detected by DAPI and CMA3 stains, respectively. The cytogenetic analysis revealed that
telomeric sequences are restricted to the terminal ends of all chromosomes and the rDNA loci are
localized in one pair of microchromosomes in both species. The karyotype of the Sicilian endemic
E. trinacris with diploid number 2n = 50, consisting of 13 pairs of macrochromosomes and 12 pairs
of microchromosomes, is presented here for first time. Our comparative examination revealed
similar cytogenetic features in Emys trinacris and the closely related E. orbicularis, as well as to other
previously studied emydid species, demonstrating a low rate of karyotype evolution, as chromosomal
rearrangements are rather infrequent in this group of turtles
First data on the genetic structure of Trachemys scripta populations in Sicily (Testudines: Emydidae)
Full text linkThe pond slider Trachemys scripta is one of the most widespread alien turtle species in the world. Its
unregulated trade and the consequent uncontrolled releases into the wild led to negative impacts on the native turtles of
the invaded areas. In Italy, alien pond sliders are widely spread, and the occurrence of hatchlings and well-established
populations is known in some areas. However, to date in Sicily, only a single female of Trachemys scripta laying eggs was
reported. Besides that, nothing is known about the actual reproduction success and establishment of self-sustaining
T. scripta populations in Sicily. Therefore, based on 14 previously characterised highly polymorphic microsatellite loci,
we aimed to unravel if the alien turtles successfully reproduce in Sicily, in both natural and semi-natural areas (i.e., lake
“Biviere di Gela” and “Parco d’Orléans”, respectively). Our results show a clear structuring of the two studied
populations. Several full-sibling relationships between the sampled turtles were found, suggesting actual reproduction in
the wild of the pond sliders in Sicily. However, further sampling is desirable since no parent-offspring relationships were
observed in the studied populations. Due to our results, systematic monitoring of alien pond sliders in the whole of Sicily
is crucial for better planning of mitigation strategies in order to protect the native biota of Sicilian inland waters
Further evidence of the southern Mediterranean medicinal leech Hirudo verbana (Annelida, Hirudinea) feeding on fish, with a review of the use of fish hosts by Hirudo spp.
No full textAlthough often considered primarily hematophagous on mammalian blood, the leeches belonging to the genus Hirudo can feed on several other vertebrate hosts. However, to date, little is known about the feeding ecology of medicinal leeches in the wild, and the few available observations mostly deals with the European medicinal leech, Hirudo medicinalis. Since even closely related Hirudo species have different functional morphology and ecological preferences, the observations carried out on one species cannot be automatically generalized to the other medicinal leeches, and targeted surveys must be realised to better understand the feeding habits of these leeches. A wide geographical belt ranging from the Iberian Peninsula to the Caucasus and Central Asia is inhabited by the southern European medicinal leech, Hirudo verbana. Although quantitative data are missing, the species seems characterized by a general decline throughout its distribution range, whose causes are not fully understood. Accordingly, a better understanding of H. verbana dietary composition is crucial to characterise its role in the trophic webs of the ecosystems it inhabits, with important consequences for the correct management of the populations of the species. Here, we report the observation of Hirudo verbana feeding on fish in the wild in southern Italy. This observation constitutes one of the first direct evidences of the species using fish as host organisms, since to date wild H. verbena had been observed mostly feeding on amphibians and mammals. Such information is useful to better characterise the diet of the wild populations of H. verbana, and to understand the trophic resources which could be exploited by the species in different ecosystems. Finally, a review of all the available evidence dealing with the use of fish as hosts organisms by Hirudo spp. is carried out
DNA taxonomy of the potamid freshwater crabs from Northern Africa (Decapoda, Potamidae)
No full textThe Mediterranean area, from southern Balkans to western Maghreb, is inhabited by the Potamon subgenus Euthelphusa, with three currently recognised species. The Maghrebian species P. (E.) algeriense is isolated from other Potamon species by the Mediterranean Sea and the Sahara Desert, and nearly no molecular data are currently available for this taxon. Present study investigated the mtDNA and nuDNA diversity in Potamon algeriense s.l. with the aims of exploring its molecular diversity pattern throughout its known distribution range, and testing the possible presence of cryptic taxa currently lumped under this binomen. The phylogenetic and DNA taxonomy analyses showed the presence of two well‐supported clades of species rank within P. algeriense s.l, with an eastern clade including the populations from Tunisia and Numidia, and a western, highly structured clade including the populations from central Algeria and Morocco. In agreement with a typical Maghrebian biogeographic pattern, the distribution of these two species shows a clear east–west divide, with a disjunction zone located in Kabylia, and a strong link between molecular diversity and segregation within different hydrographical basins is evident. The Maghreb thus proved to host an unexpectedly high genetic diversity of, and to constitute a biodiversity hot‐spot for, the Potamon subgenus Euthelphusa. In the light of the existence of two well‐characterised species currently lumped under P. algeriense s.l., and of their noteworthy molecular structuring, the status of Maghrebian Potamon populations should be re‐assessed for both the species present in the area, which are to be considered as independent management units
First records of the Brahminy blindsnake, Indotyphlops braminus (Daudin, 1803), in Italy (Squamata: Typhlopidae)
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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