Evolutive pattern of Calomys hummelincki (Husson, 1960; Rodentia, Sigmodontinae) inferred from cytogenetic and allozymic data.

The main purpose of this research was to understand the evolutive history of the sigmodontine rodent Calomys hummelincki (Husson 1960), tribe Phyllotini from chromosomal and allozymic data, and evaluate the hypotheses that explains the colonization and evolution of sigmodontine rodents in South America. C. hummelincki is restricted to the Northern South American region, which comprises Venezuela, Aruba and Curaçao islands where specimen sampling was done. The cytogenetic analysis showed that all populations studied have the same diploid number (2n=60) and fundamental number (FN=64). Constitutive heterochromatin was observed on pericentromeric positions in almost all chromosomes. NOR regions were observed on four pairs of acrocentric chromosomes. G-banding allowed us to identify almost all pair positions in the C. hummelincki chromosome complement. The G-banding also permitted a comparison of the C. hummelincki pattern with those published for C. callidus, C. venustus and C. laucha species. G-banded information indicates that hummelincki is not directly derived from laucha. The results are constrained with published allozymic and molecular data obtained in previous studies. The overall analysis seems to support Reig´s hypothesis of a south to north colonization of genus Calomys in South America

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

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

Biochemical systematics and evolution of Myoxidae

<strong>Abstract</strong> Genetic variation and divergence were analysed among 43 populations representing the five western Palaearctic genera of the family Myoxidae: <em>Myoxus</em>, <em>Myomimus</em>, <em>Muscardinus</em>, <em>Eliomys</em> and <em>Dryomys</em>. Intraspecific and interspecific genetic divergence were evaluated by electrophoretic analysis of 38-42 gene loci and compared with data from fossil records. The mean values of heterozygosity per locus for each species ranged from 0.024 in <em>Myomimus roachi</em> to 0.062 in <em>Dryomys nitedula</em>. The mean values of intraspecific genetic distance ranged from 0.04 in <em>Dryomys nitedula</em> to 0.081 in <em>Eliomys melanurus</em>. A comparison of the five genera, based on 38 gene loci indicated a high level of differentiation. Only two loci were found monomorphic and fixed for the same allele in the five genera: <em>Ldh-2</em> and <em>Got-2</em>. The lowest mean value of genetic distance was observed between the genera <em>Myoxus</em> and <em>Eliomys</em> (<em>D</em> = 1.283). <em>Muscardinus</em> displayed a higher value of genetic distance in comparison with <em>Myoxus</em> and <em>Eliomys</em> (<em>D</em> = 1.629). The highest mean value of genetic distance was displayed by these three genera in comparison with <em>Myomimus</em> and <em>Dryomys</em> (<em>D</em> = 2.251). A high value of genetic distance was also observed between <em>Myomimus</em> and <em>Dryomys</em>: <em>D</em> = 1.811. These values are in agreement with the ancient origin of this family, that had its highest expansion and diversification during the Miocene. <strong>Riassunto</strong> <strong>Sistematica biochimica ed evoluzione dei Myoxidae</strong> - Sono stati analizzati variabilità genetica e differenziamento genetico in 43 popolazioni rappresentanti i cinque generi paleartico-occidentali della famiglia Myoxidae: <em>Myoxus</em>, <em>Myomimus</em>, <em>Muscardinus</em>, <em>Eliomys</em> e <em>Dryomys</em>. La divergenza genetica intra- ed interspecifica è stata valutata mediante analisi elettroforetica di 38-42 loci genici e confrontata con dati derivati da reperti fossili. I valori medi di eterozigosi per locus per ogni specie sono compresi tra 0,024 in <em>Myomimus roachi</em> e 0,062 in <em>Dryomys nitedula</em>. I valori medi di distanza genetica intraspecifica sono compresi tra 0,04 in <em>Dryomys nitedula</em> e 0,081 in <em>Eliomys quercinus</em>. Un confronto fra i cinque generi, basato su 38 loci genici, ha indicato un elevato livello di differenziamento. Soltanto due loci sono risultati monomorfici e fissati per lo stesso allele nei cinque generi: <em>Ldh-2</em> e <em>Got-2</em>. Il più basso valore medio di distanza genetica è stato osservato tra i generi <em>Myoxus</em> e <em>Eliomys</em> (<em>D</em> = 1,283). <em>Muscardinus</em> presenta un valore di distanza genetica maggiore in confronto con <em>Myoxus</em> ed <em>Eliomys</em> (<em>D</em> = 1,629). Il valore più elevato di distanza genetica è stato osservato confrontando questi tre generi con <em>Myomimus</em> e <em>Dryomys</em> (<em>D</em> = 2,251). Un elevato valore di distanza genetica è stato anche osservato tra <em>Myomimus</em> e <em>Dryomys</em> (<em>D</em> = 1,811). Questi valori sono in accordo con l'antica origine di questa famiglia, che ha avuto la massima espansione e diversificazione durante il Miocene

Chromosomal variation and systematics of Myoxids

<strong>Abstract</strong> A synopsis of cytogenetic studies performed on various species and populations of myoxids is presented. Interspecific phylogenetic relationships derived from chromosomal data are evaluated and the evolutionary importance of intraspecific karyotypic variation is discussed. New data on the karyotypes of <em>Dryomys nitedula</em> from Asia and <em>Muscardinus avellanarius</em> from Europe are presented and discussed with special emphasis on the contrasting pattern of chromosomal differentiation in <em>Eliomys</em> vs. <em>Dryomys</em> and other myoxids. A bibliography of myoxid cytogenetics and karyology is compiled. <strong>Riassunto</strong> <strong>Variazione cromosomica e sistematica dei Mioxidi</strong> - Viene presentata una sinossi degli studi citogenetici effettuati su varie specie e popolazioni di Mioxidi. Vengono valutate le relazioni filogenetiche interspecifiche derivate da dati cromosomici e viene discussa l'importanza evolutiva della variazione cariotipica intraspecifica. Vengono presentati nuovi dati sui cariotipi di <em>Dryomys nitedula</em> asiatico e di <em>Muscardinus avellanurius</em> europeo e discussi con particolare enfasi sul contrastante pattern di differenziamento cromosomico di <em>Eliomys</em> rispetto a <em>Dryomys</em> ed altri Mioxidi. Viene compilata una bibliografia su citogenetica e cariologia dei Mioxidi

Parasitic helminths of small mammals in Elba Island

We investigated the helminth fauna of small mammals (Rodentia and Insectivora) in the mediterranean island of Elba (Italy). We first performed a survey of the parasitic helminths of <em>Rattus rattus</em> (L., 1758), <em>Mus domesticus</em> (Schwarz & Schwarz, 1943) (Rodentia, Murinae), <em>Crocidura suaveolens</em> (Pallas, 1811) (Insectivora, Soricidae) and <em>Erinaceus europaeus</em> L., 1758 (Insectivora, Erinaceidae). An expedition was undertaken in January 2002 making an helminth faunistic study of: 14 <em>R. rattus</em>; 11 <em>M. domesticus</em>; 2 <em>C. suaveolens</em> and 1 <em>E. europaeus</em>. A total of 28 animals were trapped at seven stations and nine helminth species were detected: <em>Corrigia vitta</em> Dujardin, 1845 (Dicrocoelidae), <em>Brachylaima erinacei</em> Blanchard, 1847 (Brachylaimidae) [Digenea]; <em>Hymenolepis diminuta</em> (Rudolphi, 1819); <em>H. tiara</em> (Dujardin, 1845) (Cestoda, Hymenolepididae); <em>Aonchotheca erinacei</em> Rudolphi, 1819; <em>Capillaria hepatica</em> Bancroft, 1893 (Trichuridae); <em>Mastophorus muris</em> (Gmelin, 1790) (Spirocercidae); <em>Paracrenosoma kontrimavinchusi</em> Guenov, 1978 (Metastrongylidae); <em>Syphacia muris</em> (Yamaguti, 1935) (Oxyuridae) [Nematoda]. The house mice were not infected by helminths. In the black rat, five species were detected: <em>C. vitta</em>, <em>H. diminuta</em>, <em>C. hepaticum</em>, <em>M. muris</em> and <em>S. muris</em>. Insectivores hosts were parasitised by <em>B. erinacei</em>, <em>A. erinacei</em> (<em>E. europaeus</em>), <em>H. tiara</em> and <em>P. kontrimavinchusi</em> (<em>C. suaveolens</em>). All species were identified by morphological characteristics and in the cases of <em>H. diminuta</em> and <em>M. muris</em> isozyme electrophoresis were used to compare with continental and insular samples. Helminths found in these hosts in Elba Island (apart of <em>P. kontrimavinchusi</em>) are the best colonisers of mediterranean islands. These species were found both near continental areas (Iberian Peninsula, France and Italian Peninsula) and mediterranean islands. Most of species found in the helminth faunas have an indirect life cycle except <em>S. muris</em> and <em>C. hepaticum</em>. This study was partially supported by the ?Comissionat per Recerca i Universitats de la Generalitat de Catalunya? 2001SGR00088

Chromosome analysis of three species of Myoxidae

<strong>Abstract</strong> Karyotype analysis was carried out on three species of dormice: <em>Myoxus glis</em>, 4 populations from Northern and Southern Italy and from Turkey; <em>Dryomys nitedula</em>, 4 populations from Northern and Southern Italy, from Israel and from Turkey; <em>Myomimus roachi</em>, 1 specimen from Turkey. <em>Myoxus glis</em> shows 2n=62; comparison of our specimens from different localities shows complete correspondence between karyotypes, both for the autosomes and the heterochromosomes. <em>Dryomys nitedula</em> shows 2n=48. All populations we studied, show the same karyotypic pattern, except for the NOR-bearing chromosomes. <em>Myomimus roachi</em>, here studied for the first time, shows 2n=44. All the autosomes are biarmed of decreasing size. The X-chromosome is a medium size metacentric, while the Y-chromosome is the smallest one. All the three species we studied, show one pair of NOR-bearing chromosomes, Ag-NORs always correspond to the secondary constriction. Differences in the fundamental number and in heterochromosome morphology, have been observed by other authors, in different European populations. This variability is analysed and discussed. <strong>Riassunto</strong> <strong>Analisi cromosomica in tre specie di Myoxidae</strong> - L'analisi cromosomica è stata condotta su popolazioni europee di tre specie di Myoxidae: <em>Myoxus glis</em>, 4 popolazioni provenienti dal Nord e Sud Italia, e dalla Turchia; <em>Dryomys nitedula</em>, 4 popolazioni provenienti dal Nord e Sud Italia, da Israele e dalla Turchia; <em>Myomimus roachi</em>, 1 esemplare, proveniente dalla Turchia. <em>Myoxus glis</em> presenta 2n=62. Gli esemplari, provenienti dalle diverse popolazioni, mostrano corrispondenza nella morfologia sia degli autosomi che degli eterocromosomi. <em>Dryomys nitedula</em> presenta 2n=48. La morfologia dei cromosomi nei cariotipi appare corrispondente mentre diversa è la localizzazione degli Ag-NOR. <em>Myomimus roachi</em>, del quale viene analizzato per la prima volta il cariotipo, presenta 2n=44. Tutti i cromosomi sono metacentrici o submetacentrici di dimensioni decrescenti; il cromosoma X è un metacentrico di medie dimensioni, mentre l'Y è il più piccolo elemento dell'assetto. Le tre specie da noi studiate mostrano tutte una sola coppia di cromosomi postatori di NOR, gli Ag-NOR sono sempre localizzati in corrispondenza di una regione eterocromatica. Vengono analizzate e discusse le differenze osservate, da altri autori, in altre popolazioni europee, riguardo al numero fondamentale e alla morfologia degli eterocromosomi