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The Dahomey Gap in West Africa is a human-derived savannah-like vegetation zone interspersed by patches of moist forest, with large rainforest blocks at both West (Upper Guinean Forest) and East (Lower Guinean Forest) of its limits. Togo is a tiny country situated in the middle of the Dahomey Gap. In this paper, a biogeographic analysis of the composition of the mammalian fauna of Togo is presented, by classifying each species on the basis of five distinct ecological distribution patterns. The greatest proportion of species were Pan-African (88.0%). Excluding the Pan-African species from the analysis, the mammalian fauna appeared to be affiliated similarly to both Upper Guinean and Lower Guinean Forest blocks. Only three endemic species were observed, all of them being rodents: Cryptomys zechi (Batyergidae), Funisciurus substriatus (Sciuridae), and Leimacomys buettneri (Muridae). Considering only the multispecies genera, the great majority did not show any barrier effect by the Dahomey Gap on their own species, as all of them did occur on both sides of Togo. A barrier effect by the Dahomey Gap was uncovered in 8 genera; overall, the Dahomey Gap apparently showed a barrier effect on 28.6% of the multispecies genera. It is emphasized that the full understanding of the role of the Dahomey Gap as a biogeographic barrier and of its island forests as centers of endemism is impeded by the lack of biogeographic reviews and meta-analyses on the composition of faunal and floral groups of the entire region.

In an era of environmental crises, conservation and management strategies need a new generation of applied ecologists. Here, we stimulate the next-generation applied ecologists to acquire a pragmatic mentality of problems solvers in real contexts, using the wide arsenal of concepts, approaches and techniques available in the project management (PM) arena using a road map based on the main steps of conservation project cycle. The acquisition of the conceptual and operational framework of PM can allow the next-generation applied ecologists to take on a more important role in nature conservation strategies: from data samplers, analyzers and interpreters to suppliers of solutions and decisions driving changes in species' targets inhabiting real contexts. Since the high number of applied ecologists, this change in approach (from analytical to operational) could make the difference in conservation science. We also provided, as a conceptual framework, a set of suggestions and approaches useful to facilitate this change.

Tropical savannah ecosystems are characterized by extensive grasslands with more or less sparse trees and thickets, and are threatened globally by anthropogenic forces. These grassland habitats house a rich and diversified fauna assemblage, with some of its conspicuous elements (for instance, small mammals) that have not been sufficiently investigated so far. In this paper, we meta-analyze the literature data available on the community structure and diversity patterns of shrews and rodents in West African savannahs. Overall, 10,197 small mammal individuals belonging to 111 species of Rodentia and 55 species of Soricomorpha were found in the various studies carried out in the countries covered by the present study. Studies using a combination of methods (e.g., live trapping, pitfalls, cover boards, visual encounter) detected more species in both Soricomorpha and Rodentia, and there was a positive survey (=trap ⁄ night) effort effect on the species richness in rodents. GLM models showed (i) that there was also no effect of trapping design (transect versus grid) on species richness per site, (ii) in both rodents and soricomorphs, the number of savannah species by country depended on the total species richness of that given country, but there was no effect of the relative surface covered by savannahs in that country. The number of sympatric species per site was 2.73± 1.7 (range = 1-7) in Soricomorpha and 6.33 ± 3.8 (range 1-15) in Rodentia. Dominance index was significantly different among countries, with Nigeria having lower values than all other countries and Ghana, Benin and Sierra Leone had significantly highest values. The conservation implications of the observed patterns are discussed.

The assessment of habitat selection and temporal patterns of activity rhythms is paramount for wildlife conservation. Studies on behavioural ecology of wild mammals are particularly challenging in tropical areas, mostly when involving rare or elusive species. Despite being a common species in Italy, the crested porcupine Hystrix cristata is threatened of extinction throughout most of its sub-Saharan range. All available information on the ecology of this species has been collected in Italy, whereas no data is present in the scientific literature on spatiotemporal behaviour of this large rodent in Africa. In this work, we attempted to determine habitat selection and temporal patterns of activity rhythms of the crested porcupine in northern Benin and neighbouring countries, through intensive camera-trapping. We collected a total of 146 records of crested porcupine, 91 in the dry season (October-March) and 55 in the rainy season (April-September). Porcupines used most habitats in proportion to their local availability, while selecting rock outcrop formations (possibly used as shelter sites) and avoiding open areas, wetlands and gallery forests. A mostly nocturnal behaviour was confirmed throughout the year, with some diurnal activity at the start and at the end of the rainy season. The importance of rains in determining birth peak has been also showed, with juvenile individuals always observed at the start and at the end of the rainy season. Full moon always inhibited activity of this large rodent, most likely evolved as an antipredatory behaviour to limit encounters with potential predators (common leopard Panthera pardus, spotted hyaena Crocuta crocuta and honey badger Mellivora capensis) and humans. Poaching pressure towards porcupines in West Africa is strong. Porcupines are killed for the traditional medicine, for their meat and because they are widely considered as a crop pest. This assessment should therefore be used as a basic tool to design conservation plans to preserve this rodent species in its native range.

Gia Lai bent-toed gecko (Cyrtodactylus gialaiensis) was firstly described in 2017, and is an endemic species with very restricted distributional range, estimated to be less than 10 km2 in coffee plantation in Gia Lai province, Central Highland of Vietnam. This species is listed as Critically Endangered (CR) in the IUCN Red List. To date, the natural history of this species is totally unknown. In this paper, we provide the first-of-ever natural history data on this highly threatened gecko species, with emphasis on morphometrics, habitat preferences, thermal ecology, and activity patterns. In 23 days of surveys, we captured 42 C. gialaiensis individuals and recaptured 4 of them. Sex ratio was not skewed from equality and juveniles accounted for 23.8% of the observed individuals. The two sexes did not differ in terms of mean Snout-to-Vent Length, Tail Length and weight, but the adult females had longer head than adult males. Geckos were observed at a mean substratum temperature of 24.2±1°C (n=14), and exhibited a mean body temperature of 29.5±2.5°C (n=14). There was no significant correlation between substratum and body temperatures. Body temperatures were significantly higher than substratum temperatures. The study species exhibited a clearly nocturnal above-ground activity, with main peak occurring between 20:00-21:30 h.

Adult sex ratios and age structures are important wildlife population parameters, but they have been poorly investigated in ungulate species in West African savannahs. We used line transects to investigate these parameters in 11 ungulates from a protected area in south-western Burkina Faso during the period 2010-2018. We created an empirical model of “detectability” for each species based on its main ecological characteristics (habitat and group size) and body size, and then compared the observed interannual inconsistency in sex ratios and age structures with the a priori detectability score. Six out of 11 species showed low interannual inconsistency in sex ratio and age structure. In 82% of the study species, however, the predicted detectability score matched the observed score, with two exceptions being Tragelaphus scriptus and Sincerus caffer.

Many practices have been proposed in conservation education to facilitate a re-connection between nature and the young digital generation in anthropized contexts. In this paper we suggest that, at least in some specific circumstances (urban and suburban areas), non-native invasive species may have a paradoxical and positive impact in conservation education strategies, playing a role as an experiential tool, which represents a cultural ecosystem service, i.e. an ecosystem service that produces cultural benefits by improving pro-environmental behaviours in young people.

Ecological data on ungulate mammals are poorly available for Togo (West Africa), also with regard to the populations inhabiting the various protected areas. To provide preliminary data on the ecology of Togolese ungulates, several field missions were carried out between September 2014 and August 2017 in the various ecological units considered as key areas for large mammals of the Mono Transboundary Biosphere Reserve (MTBR). MTBR, located along the Mono River, has several ecological units of varying sizes, with the Togodo Protected Areas Complex being the largest within the biosphere reserve (25,500 ha). A total of 12 species belonging to four families were recorded on the basis of direct observations and/or signs of presence. These include: Tragelaphus eurycerus, Tragelaphus gratus, Tragelaphus phaleratus, Syncerus brachyceros, Kobus kob, Philantomba walteri, Cephalophus rufilatus, Cephalophus sylvicultor, Sylvicapra grimmia, Hippopotamus amphibius, Potamochoerus porcus, Phacochoerus africanus. Another species (Kobus ellipsiprymnus) has been reported from hunter surveys. The field sightings of ungulates were especially concentrated in the Togodo protected area complex, but also the smaller ecological units (such as the Afito pools, the Avéve forest and the Akissa forest) seemed to play an important role in consolidating the ecological functioning of th biosphere reserve. Indeed, groups of T. gratus, T. phaleratus and H. amphibius are reported by hunters to seasonally move between the complex of protected areas of Togodo and its units.

Recent molecular evidence suggests that Sciurus vulgaris populations from Calabria (southern Italy) are distinct from those occurring in northern and central Italy. Here, we re-analyzed using multivariate and univariate techniques an historical dataset provided by Cavazza (1913), who documented measurements for the now extinct squirrel population from Campania. Both univariate and multivariate analyses confirmed that the sample from Calabria was homogenous and relatively distinct compared to the rest of the squirrel samples.

African manatees (Trichechus senegalensis) and crocodiles are threatened species in parts of their range. In West Africa, crocodiles may constitute the main predators for manatees apart from humans. Here, we explore the macro-habitat selection of manatees and two species of crocodiles (West African crocodiles Crocodylus suchus and dwarf crocodile Osteolaemus tetraspis) in the Niger Delta (Nigeria), testing the hypotheses that (i) manatees may avoid crocodiles in order to minimize risks of predation, and (ii) the two crocodile species do compete. The study was carried out between 1994 and 2010 with a suite of different field techniques. We observed that the main macro-habitat types were freshwater rivers and coastal lagoons for manatees, mangroves for West African crocodiles, and rivers and creeks for dwarf crocodiles, with (i) the three species differing significantly in terms of their macro-habitat type selection, and (ii) significant seasonal influence on habitat selection of each species. Null models for niche overlap showed a significantly lower overlap in macro-habitat type use between manatee and crocodiles, whereas the two crocodiles were relatively similar. Null model analyses did not indicate any competitive interactions between crocodiles. On the other hand, manatees avoided macro-habitats where crocodiles, and especially West African crocodiles, are abundant.

The presence of Crocidura sicula Miller, 1900 is reported for the first time from the Comino island. Two specimenswere obtained from the analysis of Long-eared Owl Asio otus (Linnaeus, 1758) pellets.

Rapoport’s rule states that species at high latitudes have broader ranges than species at low latitudes. This rule has been strongly disputed over the years, and the majority of current scientists think that this is mostly a local phenomenon. However, if Rapoport’s rule applies, it should be a priori expected that taxa occurring in equatorial and tropical regions should be more threatened than those at temperate regions. In this paper, we test 1) whether Rapoport’s rule applies to Sciuridae genera (Mammalia, Rodentia) and, if so, 2) whether the research efforts by scientists have been concentrated on those taxa that, because of their range size, may be predicted to be more threatened (i.e. equatorial and tropical taxa). Distribution data on Sciuridae came from literature and were transformed as maps according to World Map Program, and data about number of papers published by genus and by latitude were collected from the ISI Web of Knowledge. Our analysis verified the occurrence of a Rapoport’s effect in Sciuridae in both the hemispheres: mean range size increased significantly with latitude increases in both hemispheres. However, literature data inspection revealed that only a few genera accounted for the great majority of studies, and these genera were widely distributed and found at high latitudes. Thus, there is a potentially serious gap between current knowledge and threat expectations for Sciuridae worldwide. We therefore strongly urge scientists to give priority attention towards field studies of tropical Sciuridae genera.

Although rodents are not considered among the most threatened mammals, there is ample historical evidence concerning the vulnerability to extinction of several rodent phylogenetic lineages. Owing to the high number of species, poor taxonomy and the lack of detailed information on population status, the assessment of threat status according to IUCN criteria has still to be considered arbitrary in some cases. Public appreciation is scarce and tends to overlook the ecological role and conservation problems of an order representing about 41 percent of mammalian species. We provide an overview of the most relevant information concerning the conservation status of rodents at the genus, subfamily, and family level. For species¿poor taxa, the importance of distinct populations is highlighted and a splitter approach in taxonomy is adopted. Considering present constraints, strategies for the conservation of rodent diversity must rely mainly on higher taxon and hot-spot approaches. A clear understanding of phyletic relationships among difficult groups -such as Rattus, for instance- is an urgent goal. Even if rodent taxonomy is still unstable, high taxon approach is amply justified from a conservation standpoint as it offers a more subtle overview of the world terrestrial biodiversity than that offered by large mammals. Of the circa 451 living rodent genera, 126 (27,9 %), representing 168 living species, deserve conservation attention according to the present study. About 76 % of genera at risk are monotypic, confirming the danger of losing a considerable amount of phylogenetic distinctiveness.

Tradizionalmente, differenti approcci alla conservazione sono stati adottati in maniera indipendente l'uno dall'altro. L'attenzione dei programmi di conservazione si è incentrata alternativamente sulle specie incluse nelle liste rosse, sulle aree più ricche di specie, sui taxa con maggiore "diversità filogenetica" e, infine, su specie considerate come "indicatori" ecologici dell'integrità degli ecosistemi. Sarebbe forse auspicabile, in considerazione delle limitate risorse disponibili, giungere ad una sintesi specialmente per quanto riguarda le iniziative di conservazione a scala locale. Ciò appare particolarmente importante in Italia, in quanto le liste delle specie protette dall'Unione Europea non appaiono soddisfacenti nell'indirizzare l'attenzione verso la parte più significativa della biodiversità del nostro Paese. In assenza di dati filogenetici, abbiamo utilizzato come "surrogato" una serie di parametri derivati dalla sistematica, tassonomia e distribuzione macrogeografica dei Mammiferi dell'Italia centrale, al fine di identificare quei taxa prioritari per programmi di conservazione e monitoraggio. Abbiamo poi comparato i risultati di questa classifica "tassonomica" con una scala di sensibilità ecologica alla frammentazione ambientale, ottenuta dalla letteratura. Le due analisi concordano nell'assegnare alti valori ai Gliridi e al genere Neomys e, a seguire, al genere Sorex. Carnivori e Chirotteri ricevono valori "tassonomici" molto bassi a fronte spesso di un valore ecologico a volte considerevole, che si scontra però anche con difficoltà nel monitoraggio. Appare necessario, inoltre, valutare la sensibilità delle specie alle diverse componenti del processo di frammentazione (area, isolamento, qualità/risorse), fattori che tra l'altro ricalcano la metodologia d'individuazione delle specie focali proposta da Lambeck (1997). I dati inerenti i valori minimi dei suddetti fattori per il mantenimento della vitalità di meta-popolazioni di specie sensibili in Italia sono carenti, e ciò rallenta la definizione di iter oggettivi per l'identificazione di strategie di pianificazione (specie target) e conservazione (specie focali o specialiste sequenziali). I primi risultati sembrano indicare che è possibile conciliare almeno due dei maggiori approcci alla conservazione, focalizzando l'attenzione sia sull'unicità filogenetica di un gruppo che sull'integrità dell'ecosistema.

L'attuale distribuzione delle specie di Insettivori e Roditori in Italia riflette la dinamica geologica, la storia climatica e i processi ecologici avvenuti nel corso del Pleistocene. Al fine di ricostruire le recenti relazioni evolutive dei vari taxa, partendo da un confronto tra le cenosi a micromammiferi durante il Pleistocene-Olocene con quelle attuali, si analizzano i pattern di distribuzione e, quando disponibili, i dati genetici (filogeografici) delle singole specie dei due ordini. Delle 108 specie di mammiferi (escluse 14 specie marine) presenti in Italia tra il 40.7% e il 45.3% appartengono a Insettivori (16-19 specie) e Roditori (28-30). Cinque sono le specie endemiche di Insettivori e solo una, o forse due, di Roditori. Due taxa endemici appartengono alla regione Alpino-Appenninica, uno all'Alpino-Orientale, due-tre all'Appenninica e uno all'Insulare (Sicilia). Una sola specie (Castor fiber) si è estinta in tempi storici (XVI-XVII secolo). Cinque sono le specie di Roditori introdotte, oltre a Mus, Rattus rattus e R. norvegicus, mentre non risultano specie introdotte per gli Insettivori. I dati genetici, attualmente disponibili per alcune specie, confermano l'alto grado di differenziazione delle popolazioni che caratterizzano la Penisola italiana (al pari delle altre penisole del Mediterraneo) non solo come area di rifugio durante le ultime glaciazioni ma come un vero e proprio centro di endemismo. È auspicabile che ulteriori studi genetici, abbinati a quelli morfometrici, siano estesi a tutti i taxa di Insettivori e Roditori, prendendo in considerazione il maggior numero di popolazioni (anche attraverso una comparazione tra popolazioni di bassa e alta quota) al fine di avere delle conferme e ottenere un quadro delle conoscenze più esaustivo sulla strutturazione intraspecifica della nostra mammalofauna.

Vengono presentati i primi dati relativi ad una popolazione di Scoiattolo variabile Callosciurus sp. presente sulla costa di Maratea (PZ). La popolazione, originatasi dal rilascio di pochissimi individui in un parco privato, appare in notevole espansione; e ciò comporta notevoli rischi per le biocenosi naturali, assume grande interesse considerata per le implicazioni ambientali che ne potrebbero derivare l?intensa attività di scortecciamento che questa specie esercita sulle essenze arboree e la potenziale competizione che si potrebbe verificare con l?autoctono Scoiattolo rosso Sciurus vulgaris meridionalis. Il rischio di impatto appare particolarmente concreto in considerazione della , vista la particolare conformazione urbanistica di Maratea, con poche abitazioni immerse nel verde che costituisce un continuum con l?ambiente naturale circostante. L?area dove è stata fino ad ora accertata la presenza della specie interessa praticamente tutta la fascia costiera della Basilicata, per un?ampiezza di qualche chilometro, e riguarda i boschi costieri di Leccio Quercus ilex e Pino d?Aleppo Pinus halepensis, oltre che tutto il verde urbano e le colture arboree, dove sono stati accertati estesi fenomeni di scortecciamento su tutte le specie arboree. È questa la seconda popolazione di Callosciurus nota per l?Italia, oltre a quella presente in un parco urbano di Acqui Terme (AL).

Abstract In Italy there are four species of squirrels: the native red squirrel and other three species recently introduced. The red squirrel is present in the Italian peninsula with three subspecies, and is missing only in Salento, and Italian islands. This species is common on Alps and Apennines, while in the plains it is declining because of the habitat loss. Competition with the grey squirrel and habitat fragmentation are considered the major threats to the survival of the red squirrel. The grey squirrel is present in Piedmont and Liguria. A study on the Piedmontese colony showed that the red squirrel is disappearing from the area colonised by the grey squirrel and the damage due to bark-stripping and feeding is considerable. Free-ranging populations of the Siberian chipmunk live in Belluno, Verona, and Rome, but records of single animals were reported for other areas. The Finlayson's squirrel is present with a small nucleus in an urban area of Piedmont. Here, the impact of this species on the vegetation appears dramatic. The eradication of the grey squirrel is a priority for the conservation of the red squirrel, but control plans for the other introduced species are also needed.

Abstract A synthesis on the status of the Italian mammals species is reported. For each order, faunistic and biogeographic data and conservation concern are considered. In addition, a list of endemic, rare and/or endangered mammal species, classified according to the new IUCN criteria is provided as well as the species and subspecies recently introduced in Italian territory.

Abstract With reference to the literature and original data, a description is given of the present distribution and status of the Dormouse species found in Italy (Dryomys nitedula, Eliomys quercinus, Muscardinus avellanarius and Myoxus glis). Possible causes of reduction in numbers and distribution of the four Dormouse species are also discussed. Riassunto Distribuzione e conservazione dei Mioxidi in Italia - È riportata su dati bibliografici ed originali la distribuzione del Driomio (Dryomys nitedula), del Quercino (Eliomys quercinus), del Moscardino (Muscardinus avellanarius), e del Ghiro (Myoxus glis) in Italia. Inoltre vengono sinteticamente discusse, per ogni specie, le possibili cause di rarefazione e riduzione degli areali delle popolazioni.

Abstract The study of morphological and morphometric characteristics of Apodemus (Sylvaemus) sylvaticus and A. (S.) flavicollis is examined in this paper. The examined specimens were living in sympatry and allopatry in two Mediterranean habitat-types (a long-trunked forest and a cultivated treed field) in southern Italy. Through discriminant analysis, trends of skull measurements (which characterize the different situations of co-presence and/or absence of the two sibling species) are examined. Isometric dental measurements best discriminate the examined populations. Possible causal factors which could affect discriminant measures are discussed. Riassunto Un metodo per la discriminazione morfometrica in popolazioni di Apodemus (Sylvaemus) dell'Italia meridionale - In questo studio preliminare sono state prese in esame le caratteristiche morfologiche e morfometriche di Apodemus (Sylvaemus) sylvaticus e A. (S.) flavicollis in condizioni di simpatria e allopatria in due ambienti mediterranei (bosco maturo e campo prossimo ad un frutteto) del sud Italia. Mediante analisi discriminante sono state studiate le tendenze delle misure craniche a caratterizzare i diversi gruppi in situazione di allopatria e/o simpatria delle due specie sorelle. Le misure isometriche dentarie mostrano una maggiore capacità di discriminare i gruppi considerati. Vengono discussi i possibili fattori causali che potrebbero influire sulle misure discriminanti.

Abstract Tooth diversity of palaearctic Arvicolidae seems to be not directly and strictly linked to the environmental characters of the range of relevant populations (according to an intraspecific approach) or species (according to an interspecific approach). A significant correlation was found with the minimal (not with the average) genetic distance, as estimator of evolutionary speciation time. Such correlation was not dependent from any linkage between genetic distance and quantitative similarity of dentary forms. As mainly non-adaptative, the studied characters can be substancially affected by time "entropic" consequences on isolated informational systems. Riassunto La diversità dentaria degli arvicolidi paleartici sembra non essere direttamente e strettamente correlata alle caratteristiche ambientali degli areali di distribuzione delle varie popolazioni (secondo un approccio intraspecifico) o specie (secondo un approccio interspecifico). Una correlazione significativa è stata trovata con la minima (non con la media) distanza genetica, quale stima di tempo evolutivo di speciazione. Tale correlazione non dipende da nessun legame tra la distanza genetica e la similarità quantitativa delle forme dentarie. I caratteri studiati, essenzialmente non adattativi, possono essere influenzati da un aumento "entropico" tipico dei sistemi informazionali isolati.

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.

Abstract The setting up of a "data bank" dealing with the findings of Rodents specimens (Families: Gliridae, Arvicolidae, Muridae) of peninsular and insular Italy available for 1950-1981 years in the italian museums and collections. The file, wherever possible, has been filled up with cartographic, bioclimatic and synanthropic data. With the use of a microcomputer has thus become possible to make inquires related both to biological and environmental data. Data management allows the following function: file maintenance (insert, delete and modify record); cross - reference search; search index; report generation. In the first phase challenges have been formulated, requiring simple data processing. Some informations were obtained as reply about the prevalences in the capturing referred to sex and season, as well as the connections between Rodents coenosis and bioclimatic condition of the territory. Riassunto È stata avviata una "banca dati" dei rinvenimenti di esemplari di Roditori (Famiglie: Gliridae, Arvicolidae, Muridae) dell'Italia peninsulare ed insulare catalogati negli anni 1950-1981 nei Musei e collezioni italiani. L'archivio, laddove possibile, è stato completato con i dati cartografici, bioclimatici e sinantropici. L'uso del microcomputer ha permesso di formulare domande incrociate sia sui dati biologici che su quelli ambientali. La gestione dei dati consente le seguenti funzioni: gestione dell'archivio (inserimento, cancellazione e modifica del record); ricerca incrociata; ricerca per indice; stampa. In una prima fase sono state formulate alcune domande richiedenti semplici elaborazioni sulle preponderanze delle catture in rapporto al sesso ed alla stagione, nonché sui rapporti tra cenosi a Roditori ed assetto bioclimatico del territorio.