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Gli anfibi costituiscono un ottimo modello per esplorare gli aspetti storici della distribuzione delle specie a causa della loro bassa capacità di dispersione e della bassa vagilità individuale. I bufonidi sono una delle famiglie di Anuri più ricche di specie, tra cui il rospo comune, Bufo bufo, diffuso nelle regioni eurasiatiche. Abbiamo eseguito uno studio cariologico con tecniche standard di bandeggio C e sequenziali con fluorocromi (Cromomicina A3 (CMA) e Diamidinofenilindolo (DAPI) su diversi girini di diverse popolazioni del Centro e Sud Italia. Tutti i girini esaminati presentavano il cariotipo Bufo standard, di 2n = 22 cromosomi a due braccia, con le prime sei coppie più grandi delle altre cinque (7 - 11), e l'eterocromatina NOR associata distale sui bracci lunghi della sesta coppia di cromosomi, che era anche l'unica regione cromosomica CMA-positiva. Il bandeggio C ha evidenziato eterocromatina centromerica, DAPI positiva, su tutti i cromosomi in tutte le popolazioni studiate dell'Italia centrale. Le popolazioni dell'Italia meridionale differivano per bande C paracentromeriche aggiuntive sui bracci corti dei cromosomi 1, 3 e 5. Questi risultati supportano la suddivisione delle popolazioni centrali di B. bufo da quelle meridionali, come evidenziato anche da studi filogenetici molecolari., BORNH Bulletin of Regional Natural History, V. 2 N. 3 (2022): BORNH 03/2022

Here we report the results of a longitudinal field study (2002 -2018) aimed at monitoring the presence and the breeding activity of the Italian Green Toad, Bufotes balearicus, within the area of the administrative boundaries of Naples. We identified breeding sites in five sub-areas (Bagnoli – ex sito industriale, Mostra d'Oltremare, Parco del Poggio, Scalo Ferroviario-zona orientale, Parco Massimo Troisi), one of which (Parco M. Troisi) since 2018. Only in two subareas (Mostra d’Oltremare and Parco del Poggio) the reproductive activity took place regularly, almost every year, although the development of tadpoles was often compromised by a variety of anthropogenic disturbances. However, the major potential threat to the survival of this amphibian for the entire study area is represented by the isolation of its population mainly due to the scarcity of natural and semi-natural green areas in a highly urbanized territory. We hope that our research will be helpful to plan management activity for this species in the urban area of Naples., BORNH Bulletin of Regional Natural History, V. 1 N. 3 (2021): BORNH 03/2021

A repeated DNA sequence, named RepHv-390, isolated from DNA samples of male and female specimens of the European Western wipe snake, Hierophis viridiflavus, was used as probe for FISH analysis to detect its distribution on chromosomes of this colubrid species and of other species of the same and of different snake families. We observed positive results in all the studied species, namely: H. viridiflavus, Coronella austriaca, Elaphe quatuorlineata (Colubridae), Phisalixella variabilis (Lamprophiidae) and Vipera aspis (Viperidae). Intense and abundant hybridization signals of RepHv-390 were observed on all chromosomes of H. viridiflavus, C. austriaca, E. quatuorlineata and V. aspis and on nuclei of P. variabilis. Its wide presence on the chromosomes of all the studied species suggests that RepHv-390 is a segment of transposable element (TE) of ancient origin in snakes. Probably, the ancient TE arose in a common Colubroidea ancestor before the diversification into different lineages of this superfamily. Preliminary analysis of RepHv-390 evidenced no significant identity with any other known sequence, suggesting that RepHv-390 is a segment of an unclassified TE element

The two endemic Italian brown frog species, Rana latastei and R. italica, have a very similar morphology: the diagnostic characters are the tympanum, larger in R. latastei and the nostril distance that is almost equal to the interorbital length in R. latastei, while is slightly greater in R. italica. The most important parameter in order to discriminate between the two species is their different areals: R. latastei is mostly widespread in the Po Valley, while R. italica inhabits almost only the Apennine rivers. The S1 satellite DNA from Palaearctic brown frogs displays a different structure in all the previously tested species, and this complete species- specificity was verified also for R. latastei and R. italica. Southern Blot of DNA samples from the two species, digested with five different restriction enzymes, displays different patterns of hybrid bands. Both species present two repetitive units S1a and S1b. The S1a repetitive unit has the same size but different restriction sites, while the S1b unit differs both in size and restriction sites. In conclusion, the S1 satellite DNA is a powerful molecular marker in order to discriminate the Palaearctic brown frog species.

Anguis fragilis (Squamata: Anguidae). Sono stati studiati vari individui di tre popolazioni italiane di Anguis fragilis mediante metodi di colorazione standard dei cromosomi. Tutti gli individui studiati mostrano un cariotipo di 2n=44 elementi (20 macro- e 24 microcromosomi). Tre coppie di macrocromosomi (1, 4 e 5) sono metacentrici, la decima coppia è formata da cromosomi subtelocentrici, mentre tutti i rimanenti macrocromosomi sono telocentrici. I risultati ottenuti indicano che le popolazioni italiane di orbettino sono cariologicamente uniformi, ma differiscono dalle popolazioni centro-europee, che hanno cariotipi in cui gli elementi della decima coppia sono telocentrici.

Nel presente lavoro abbiamo esaminato la distribuzione e la densità per quadrante degli Anfibi della Campania. Gli Anfibi più comuni nella regione sono Pelophylax sp., Bufo bufo, Rana italica e Lissotriton italicus, rinvenuti in più del 30% dei quadrati UTM 10x10 km investigati. L’Anfibio più raro è Lissotriton vulgaris che è confinato all’area nordoccidentale della regione. Degna di nota è la presenza, anche in sintopia, di Salamandrina perspicillata e Salamandrina terdigitata, al momento unico caso finora noto in Italia.

A karyological study conducted by both conventional and banding staining methods (Ag-NOR-, CMA3, and C-banding) evidenced a peculiar heterochromatin pattern on chromosomes of Moldovan specimens of the agile frog, Rana dalmatina. As is normal for all agile frogs, the Moldovan population presented 2n = 26 chromosomes, with NOR loci on the short arms of the third chromosome pair, but differed in showing heavy centromeric, CMA3 positive C-bands on the seventh chromosome pair, and light centromeric, DAPI positive C-bands on five chromosome pairs. In contrast, Moldovan specimens showed no significant difference in two segments of the 16S mitochondrial rRNA gene and in the S1 satellite DNA sequence and organization, in comparison with the GenBank deposited 16S rDNA and S1 DNA satellite sequences of R. dalmatina. Molecular similarity and chromosomal differences between agile frogs from Moldovan and extra-Moldovan populations are discussed.

A new highly abundant satellite DNA from Discoglossus pictus (Dp-sat1) was isolated and characterized. The repetitive unit (0.51 kb) has 2 Hin dIII sites and only one Spe I site: digestion of genomic DNA with Hin dIII produces 3 fragments: HA (0.17 kb), HB (0.34 kb), and HC = HA + HB (0.51 kb), while digestion with Spe I produces the whole repetitive unit (0.51 kb) that contains both Hin dIII sites. Sequence analysis of cloned repeats indicates an average A + T content of 71%, with many A- and T-runs. Southern blot analysis shows an arrangement of multiple bands of the 0.51 kb monomer in Spe I-digested DNA, while Hin dIII-digested DNA shows a ladder composed of all the possible combinations of the 3 digested fragments. Quantitative dot-blot indicates that Dpsat1 accounts for about 6% of the D. pictus genome: this value represents about 1.5 ! 10 6 copies of repetitive units per nucleus. This satellite DNA is also a major repetitive DNA in 4 other Discoglossus species, in which the repetitive unit presents the same size and restriction sites except in D. montalentii where it contains a unique Hin dIII site. This DNA was absent in all the other tested archaeo- and neobratrachian species, as well as non-amphibian species. Fluorescent in situ hybridization (FISH) analysis shows that Dpsat1 is localized only in peri- and/or para-centromeric areas of the 7 small chromosome pairs, while no labeling was observed in the 7 large chromosome pairs. Remarkably, Dpsat1 heterochromatin is found only at one pole of the nucleus, suggesting that during interphase all 7 small chromosome pairs are located in the same nuclear region.

Molecular evidences that satellite DNA evolution is saltatory

The taxonomic status of B. pachypus is controversial even today. However, following recent electrophoretic studies, some authors believe that Italian populations in the area between the Po River and the southern tip of Calabria should be ascribed to the new monotypic species Bombina pachypus. The range of the Apennine yellow-bellied toad, which is endemic to Italy, extends from central Liguria to the Aspromonte area. B. pachypus is most often sighted in the small, shallow water catchments where it reproduces: temporary puddles, potholes in dirt roads, oxbow lakes and stagnant loops in streams and small basins and troughs. In southern Italy, B. pachypus is most often found in hilly and mountainous environments, whereas in northern Italy, it is normally found in planitial and hilly environments. B. pachypus is active from April to October, hibernating underground or under vegetation-covered stones usually not far from the water bodies it frequents in late autumn and winter. Bombina pachypus has a rather long reproductive period, which lasts from the end of April well into September. Apennine yellow-bellied toads can mate several times during the breeding season, which coincides with the annual period of activity. This remarkable reproductive flexibility is possible thanks to prolonged spermiation in males and to the presence of post-vitellogenic follicles in the ovaries of females throughout the activity period. Although some populations of B. pachypus are reported to have disappeared following the destruction and/or alteration of their reproductive sites, it is impossible to say for certain whether the absence of previously reported populations in other stations is due to natural demographic fluctuations or to true extinction of the local population.

Nel 2001 al Dipartimento di Zoologia dell’Università di Napoli è stata affidata la redazione della carta Ittica della Provincia di Avellino. Sono state scelte 34 stazioni rappresentative del sistema idrografico della Provincia. Le indagini hanno riguardato: 1) la valutazione della qualità delle acque mediante l’Indice Biotico Esteso (I.B.E.); 2) lo studio delle popolazioni ittiche; 3) l’indagine genetica condotta sui salmonidi per l’individuazione dei ceppi Atlantici o Mediterranei. L’I.B.E. ha evidenziato un degrado ambientale dei tratti pedemontani e collinari dei fiumi dovuto all’assenza di impianti di depurazione nei vari paesi che si affacciano sui bacini. Nei tratti montani è stata osservata una notevole integrità ambientale (I.B.E. 11-12). Acque molto inquinate sono localizzate nei pressi dei centri abitati, come nel fiume Sabato tra Atripalda ed Avellino. L’analisi genetica di Salmo trutta ha accertato la presenza contemporanea in tutti i bacini sia del ceppo Mediterraneo che di quello Atlantico, con la prevalenza del primo solo in alcuni siti. Tra i ciprinidi, le specie dominanti, ben strutturate, sono rappresentate da Leuciscus cephalus, Barbus tyberynus e Rutilus rubilio. Tra le altre specie, Telestes muticellus si localizza in biotopi reofili dove forma consistenti popolazioni. Alburnus albidus è sporadica, ma forma una comunità ben strutturata nel bacino dell’Ofanto al limite con la Provincia di Foggia. Tra le specie emergenti da segnalare, la lampreda di ruscello Lampetra planeri, frequente nel tratto medio-alto del bacino del Sele, e il gambero di fiume, Austropotamobius pallipes, apparentemente localizzato in due siti, alle sorgenti del fiume Sabato e in un affluente dell’alto corso del Calore

Pubblicato su: Boll. Sez. Campania A.N.I.S.N. (N.S.), vol.24

Pubblicato da Pianura (Cremona), vol. 13