Showing papers in "Hystrix-italian Journal of Mammalogy in 1986"

Elementi di paleobiogeografia dei mammiferi terziari dell'Italia

Abstract: Abstract In this paper the Italian continental Tertiary mammalofaunas are examined. For each known layer the faunal composition, the age and the center of spreading of each component are pointed out. Besides some isolated remains collected in marine sediments, faunistic assemblages coming from three Eocene, six Oligocene, six Miocene, three Mio/Pliocene, six Lower Pliocene, more than ten Upper Pliocene and two Pleistocene sites interesting for mammalian Tertiary biogeography are analysed. Riassunto Vengono esaminate le faune a mammiferi continentali del Terziario italiano. Per ogni giacimento viene indicata la composizione della fauna, l'eta e l'area di provenienza delle varie componenti. A prescindere dai resti isolati raccolti in sedimenti marini, vengono analizzate le faune di trentasei localita (tre eoceniche, sei oligoceniche, sei mioceniche, tre mio/plioceniche, sei plioceniche inferiori, dieci plioceniche superiori e due pleistoceniche) che presentino interesse per la biogeografia del Terziario.

On Paleobiogeography of Italian Tertiary Mammals / Elementi di Paleobiogeografia dei mammiferi terziari dell'Italia

Abstract: In this paper the Italian continental Tertiary mammalofaunas are examined. For each known layer the faunal composition, the age and the center of spreading of each component are pointed out. Besides some isolated remains collected in marine sediments, faunistic assemblages coming from three Eocene, six Oligocene, six Miocene, three Mio/Pliocene, six Lower Pliocene, more than ten Upper Pliocene and two Pleistocene sites interesting for mammalian Tertiary biogeography are analysed. Riassunto Vengono esaminate le faune a mammiferi continentali del Terziario italiano. Per ogni giacimento viene indicata la composizione della fauna, l'eta e l'area di provenienza delle varie componenti. A prescindere dai resti isolati raccolti in sedimenti marini, vengono analizzate le faune di trentasei localita (tre eoceniche, sei oligoceniche, sei mioceniche, tre mio/plioceniche, sei plioceniche inferiori, dieci plioceniche superiori e due pleistoceniche) che presentino interesse per la biogeografia del Terziario.

Trophic systems and chorology: data from shrews, moles and voles of Italy preyed by the barn owl / Sistemi trofici e corologia: dati su Soricidae , Talpidae ed Arvicolidae d'Italia predati da Tyto alba (Scopoli 1769)

Abstract: In small Mammals biogeography, available data are up to now by far too scanty for elucidate the distribution of a lot of taxa, especially with regard to the absence from a given area. In this respect, standardized quantitative sampling techniques, like Owl pellets analysis can enable not only to enhance faunistic knowledges, but also to estimate the actual absence probability of a given taxon "m", lacking from the diet of an individual raptor. For the last purpose, the relevant frequencies of "m" in the other ecologically similar sites of the same raptor species diets are averaged ($f_m$ ): the relevant standard error (multiplicated by a coefficient, according to the desired degree of accuracy, in relation of the integral of probabilities) subtracted ($\overline{F}_m - a E$): then, the probability that a single specimen is not pertaining to "m" is obtained ($P_0 = 1 - F_m + a E$); lastly, the desiderate accuracy probability ($P_d$) is chosen. Now, "$N_d$" (the number of individuals of all prey species in a single site needed for obtain, with the desired probability, a specimen at least of "m") is obtained through $$N = \frac{\ln P_d}{\ln P_0}$$ Obviously, every site-diet with more than "N" preyed individuals and without any "i" specimen is considered to be lacking of such taxon. A "usefulness index" for the above purposes is outlined and checked about three raptors. Some exanples about usefulness of the Owl pellet analysis method in biogeography are given, concerning Tyto alba diets in peninsular Italy about: - Sorex minutus , lacking in some quite insulated areas; - Sorex araneus (sensu stricto, after GRAF et al., 1979), present also in lowland areas in Emilia-Romagna; - Crocidura suaveolens and - Suncus etruscus , present also in the southermost part of Calabria (Reggio province); - Talpa caeca , present also in the Antiapennines of Latium (Cimini mounts); - Talpa romana , present also in the middle of Tuscany; - Clethrionomys glareolus , lacking in few small, insulated areas, but present in coastal woodlands; - Microtus (Pitymys) sp., apparently lacking only in some coastal areas of Toscana and Liguria, or in some Etna slopes (Linguaglossa). Riassunto Un metodo standardizzato e quantitativo di raccolta dei dati quale l'esame delle borre di rapaci consente non solo di integrare le conoscenze faunistiche, ma pure di tentare una valutazione della probabilita di assenza di un dato taxon da un'area geografica. In proposito, vengono presentati esempi originali circa Sorex minutus , Sorex araneus , Crocidura suaveolens , Suncus etruscus , Talpa caeca , Microtus (Pitymys) savii e Microtus (Pitymys) multiplex in Italia peninsulare.

On the Paleobiogeography of Pleistocenic Italian Mammals / Osservazioni sulla paleobiogeografia dei mammiferi del Pleistocene italiano

Abstract: In this paper the main Italian Pleistocene mammalofaunas are examined and a chronological sequence of the main deposits is proposed. Centers of spreading, times of first appearence in Italy and ranges through the peninsula of the more representative species are indicated, as far as possible. The insular faunas and the different degrees of endemism they show, are particularly discussed. Riassunto Vengono esaminate sinteticamente le principali faune a mammiferi del Pleistocene d'Italia e viene proposta una successione cronologica per i principali giacimenti. Per le specie piu rappresentative vengono indicati, per quanto possibile, le aree di provenienza, il momento della comparsa e la loro diffusione nella penisola. Particolare attenzione viene posta alle forme insulari ed al loro carattere endemico.

Allometric and Isometric variations in the Italian Apodemus sylvaticus and Apodemus flavicollis with respect to the conditions of allopatry and sympatry / Variazioni allometriche e isometriche in Apodemus sylvaticus e Apodemus flavicollis italiani, rispetto alle condizioni di allopatria e simpatria

Abstract: In Italy there are two species of Apodemus ( Sylvaemus ): Apodemus sylvaticus on the mainland and the main island, and Apodemus flavicollis only on the mainland. The trend of some morphometric characters of the skull (incisive foramen length - FI; interorbital breadth = IO; length of palatal bridge = PP; upper alveolar length = $M^1M^3$ ) was analized and some theoretical models verified for A. sylvaticus . If one considers the sympatric population of A. sylvaticus and A. flavicollis simultaneously the characters PP, IO and $M^1M^3$ appear significantly isometric being directly correlated ($P \leq O.O1$), while FI character results allometric with respect to the previous ones, as expected. If one considers the sympatric populations of each of the species separately, the scenario is different. For A. sylvaticus only PP and $M^1M^3$ are isometric ($P \leq 0.05$). For A. flavicollis only $M^1M^3$ and FI appear to be correlated, although not as significantly as for A. sylvaticus ($P \le 0.05$; one tail). The insular populations of A. sylvaticus do not show significant correlations, except for FI and $M^1M^3$ ($P \le 0.05$). On the contrary, considering all populations, sympatric and allopatric, of A. sylvaticus at the same time are significant correlations ($P \le 0.05$) in all combinations of characters, except for those involving the IO. We suggest that the isometric relations in sympatric assemblages are confined within a morphological range available to the genus Apodemus . In such a space, the two species are split in two different and innerly homogeneous distributions. We found no evidence to confirm the niche variation hypothesis. On the contrary, the variability expressed as SO or CV's appears higher in the sympatric populations than in the allopatric ones, for three of the four characters, confirming previous results. For the character displacement hypothesis, we found that A. sylvaticus when not found together with A. flavicollis , shows adimensional increase of PP up to an intermediate value between the mean values of A. sylvaticus and A. flavicollis sympatric assemblages. Also $M^1M^3$, FI and FI + PP increase in allopatry, but to a value greater than that of A. flavicollis ; on the other hand, IO growth in allopatry is not significant, as expected, because such character is allometric in the species under study. Lastly, the model was completely inadequate for FI, a character that in sympatry is higher in A. sylvaticus , but increases to a greater extent in the allopatric populations of A. sylvaticus . As far as the convergence on a given phenotype is concerned, the scarse available data are not in agreement with the model. The comparison between the sympatric A. sylvaticus and A. flavicollis shows a correlation of the IO and FI + PP value, when considered in the same localities ($P \le 0.05$). Similar observations were made by Tvrtkovic' (1979) on FI and $I-M^3$ (upper tooth length) for several european localities ("character's paralleling"). Moreover, for some isometric and allometric characters, the variability is higher when comparing the interspecific averages between the local and total values. This suggests that homotopic average of the cumulative dimension of the two species, is more variable than the interspecific homotopic differences. Possibly, A. sylvaticus , on the islands, where his congener is not present, tends to invade the morphological range of A. flavicollis . At A. sylvaticus specific level, all characters linked to the skull length appear isometric, whereas IO linked to skull breadth is allometric. Conversely, concerning heterospecific sympatric assemblages, the all pairs of characters linked to skull dimension are isometric, while FI (negatively linked to bones thickness and positively linked to skull length) is allometric. The intraspecific comparison perhaps reflects a gradient of skull length, whereas the interspecific one a difference in size and thickness between A. sylvaticus and A. flavicollis skull. On the other hand it appears, from Filippucci et al. (1984) that the importance of genetical factors is highly dependent on the particular character examined and on the species under study. In such a manner, results which are ecologically rather similar could be obtained with different processes. Conversely, the isometry and allopatry of characters seems to depend on different ways from the taxonomical, evolutive and ecologica1 context taken into account. Namely, some characters seem to be more subject to the competitive pressure, others to the genera1 structural model of the species. On the other hand, it is not sure that competition can explain all the observed phenomena, some of which may have a multiple base. More research is needed in order to elucidate such casual aspects of observed phenomena. Riassunto Su Apodemus sylvaticus dell'Italia insulare e su A. sylvaticus ed Apodemus flavicollis dell'Italia peninsulare sono stati studiati alcuni caratteri cranici, evidenziandone l'isometria o l'allometria. Su detti caratteri sono stati verificati e discussi i modelli eco1ogici: variazione di nicchia, spostamento dei caratteri, convergenza fenotipica e parallelismo di caratteri in condizione di simpatria e/o allopatria.

A new Appenninic station of Dryomys nitedula Pallas, 1979 (Rodentia, Gliridae) / Nuova stazione appenninica di Dryomys nitedula (Pallas, 1779) (Rodentia, Gliridae)

Abstract: A new record of Dryomys nitedula from the massif of Pollino (Southern Italy) is given and the value of the subspecific division ( D. nitedula intermedius , D. nitedula aspromontis ) in Italy is discussed. Riassunto Viene segnalato il ritrovamento di un esemplare di Dryomys nitedula sul Massiccio del Pollino e ridiscusso il valore della ripartizione sottospecifica ( D. nitedula intermedius , D. nitedula aspromontis ) in Italia.

Recent shifts of Middle-Adriatic Italian Range of Hystrix cristata Linnaeus, 1758 / Modificazioni recenti dell'areale di Hystrix cristata Linnaeus, 1758, nell'Italia centrale adriatica

Abstract: The expansion of Hystrix cristata L. in the Adriatic sea belt of Italy is reported for the first time. The diffusion area is presently limited to the north by the Foglia river. Some hypothesis on the possible causes for such expansion are presented. Riassunto Viene segnalata l'espansione di Hystrix cristata L. in zone del versante adriatico italiano precedentemente considerate al di fuori dell'areale della specie. In particolare la sua diffusione e stata seguita a partire del 1978, nelle Marche, dove al momento attuale la specie ha raggiunto i confini settentrionali. In base alle conoscenze attuali quindi l'areale dell'istrice in Italia risulta esteso anche al versante adriatico con un limite settentrionale corrispondente al decorso della valle del Fiume Foglia. Sono presentate anche ipotesi sulle possibili cause di questa espansione.

The small mammals of an upper piedmontese Po plain site (Leinì, Turin prov.) / La micromammalofauna di una stazione planiziaria piemontese

Abstract: The 24 small mammals listed as living in Leini (Piedmontese Po plain, near Turin, 245 m on sea level) (only the red fox, Vulpes vulpes is not sure), are briefly analysed (Chiroptera excepted). List and analysis are the results of studies pursued for about 35 years. However, in Verona's Museum of Natural History, the housed materials are related to the last eighteen years (1966-1984) (Tab. I). For a complete analysis, this fauna is compared with the Veronese Po plain one, especially with the Busatello one (Gazzo Veronese-Ostiglia). This site is a stretch of marshes named "Valli Grandi Veronesi and Ostigliesi" (Tab. II). In this analysis, if we don't consider the not native species ( Myocastor coypus and Mustela vison ), the estinguished species ( Lutra lutra ), the Mediterranean species (living only along the border of the Po plain basin) ( Suncus etruscus ) and the hunting species ( Lepus europaeus and Oryctolagus cuniculus ) we have 23 taxa for Lein and only 17 and 13, respectively, for Veronese Po plain and Busatello. The richer small mammal fauna of the Piedmontese Po plain is, above all, supported by different ecological conditions but the preservation of some species (e.g. Glis glis and Muscardinus avellanarius ) in Leini is surely related also to historical problems and to a land anthropization pushed forward to a lesser degree. Riassunto Vengono elencate e brevemente commentate tutte le specie di micromammiferi presenti a Leini (Torino), Chirotteri esclusi. Si tratta di un complesso di 24 specie (solo la volpe non e del tutto sicura) per ognuna delle quali gli autori, sinteticamente, espongono le osservazioni raccolte in circa 35 anni. A maggior chiarimento del significato faunistico del popolamento, viene presa in esame anche la micromammalofauna della pianura padano veneta, precisamente la pianura veronese ed in particolar modo la micromammalofauna del Busatello (Gazzo Veronese e Ostiglia), ultimo lembo delle Valli Grandi Veronesi. Ne deducono che la maggior ricchezza faunistica di Leini (Tabella II) dipende soprattutto da fattori ecologici ma anche da fattori storici, per cui l'ambiente naturale ha meglio conservato le caratteristiche originali permettendo la conservazione di alcune entita che nel Veronese invece sono andate perdute in conseguenza dell'impatto antropico.

Italian Moles: a Morphometric approach to their systematic relationships / Le talpe italiane: un approccio morfometrico alle relazioni sistematiche

Abstract: It has been performed a multivariate analysis on skeletal components (mandible) of Italian moles ( T. europaea , T. romana , T. caeca ). The results indicate that the three taxa are highly discriminated. The Wagner network produced shows a greater distance between T. romana and T. europaea than between the latter and T. caeca . The three taxa are considered phenetically as different species. Riassunto Per chiarire le relazioni sistematiche tra le talpe italiane ( T. europaea , T. romana , T. caeca ) e stata condotta un'analisi multivariata su componenti scheletrici (mandibola). I risultati indicano che i tre taxa sono altamente discriminati. Il Wagner network mostra una maggiore distanza tra T. romana e T. europaea rispetto a T. caeca . Su base fenetica i tre taxa sono quindi considerati specie separate.

Micromammals (Insectivora; Rodentia) of "Valle dell'Inferno" (Rome) / Micromammiferi (Insectivora; Rodentia) della Valle dell'Inferno (Roma)

Abstract: A research on micromammals in the area of "Valle dell'Inferno" (in the north-west of Rome) was carried out. The study was based on a previous phytosociological survey which describes a Quercus suber population in the valley (a once larger residua1 of a roman cork-tree wood which is now included in the town). Specimens from Rodents ( Apodemus sylvaticus , Mus domesticus , Rattus rattus , R. norvegicus , Pitymys savii ) and Insectivores ( Crocidura suaveolens , Erinaceus europaeus ) were captured by live traps. Most of Insectivores specimens are represented by C. suaveolens . Generally C. suaveolens lives in sympatry with C. leucodon but no specimens of the latter were found in this area. Three different kinds of landscape are present in the "Inferno" valley, namely, the wood, the meadow, and the bottom valley (with high anthropic impact); we have compared these three landscapes with biotic indexes (index of faunistic affinity, index of biocoenotic affinity and index of environmental evaluation). We have also compared through the same indexes, the micromammal fauna of the "Inferno" valley with six other differently polluted localities in Latium, where animals were captured with the same live traps. This area retains its natura1 environment in despite of the high anthropic impact. Riassunto E stato effettuato uno studio sulla micromammalofauna terrestre della Valle dell'Inferno situata a nord-ovest di Roma. Lo studio e basato su una precedente indagine fitosociologica effettuata per la caratterizzazione vegetazionale di una sughereta un tempo molto estesa ed ora racchiusa nell'abitato cittadino. E stato pertanto possibile tracciare, tramite gli indici biotici, una correlazione tra microteriocenosi ed effetti dell'impatto antropico.