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Nullo Glauco Lepori: note biografiche
Breve biografia del professor Nullo Glauco Lepori, direttore dell'Istituto di Zoologia dell'Università degli studi di Sassari e poi preside della Facoltà di Scienze
Resoconto annuale dei Vertebrati terrestri della Sardegna: 1987
Sightings of 111 bird species in 1987 are briefly reported
Primi dati sulla distribuzione geografica di planarie del gruppoDugesia lugubris-polychroa(Turbellaria, Tricladida) in Sardegna, con particolare riguardo alla presenza di una mutazione tetraploide nel fiume Cixerri (Siliqua, Cagliari)
The finding of a Planarian of theDugesia lugubris-polychroagroup characterized by a tetraploid chromosome set of 4n=16; n=4 is reported. This is therefore a tetraploid mutation that has never been reported before in Sardinia.Besides mitotic metaphase plates with 16 chromosomes, which are by far the most frequent (78% of the counts), others containing fewer chromosomes, believed to be derived from segregational mitoses, were also observed
Sulla presenza diCrenobia alpina(Dana) (Turbellaria, Tricladida) in Sardegna
The presence of the stenothermic cold-water planarianCrenobia alpina(Dana) has been evidenced in Sardinia for the first time. Identification of
the freshwater species was made on the basis of its physio1ogical and morpho-anatomical characteristics.Furthermore the cytological data demonstrated that this population
presents a polyploid karyotype with a marked tendency to aneuploidy.The specimens were collected from three sites in the Gennargentu mountains as well as from a fourth at «Funtana Bona» near Orgosolo.The finding of Crenobia alpina in Sardinia shows that the distribution of this species extends further south within the Mediterranean area than previous reports would suggest
Rinvenimento di una Planaria ascrivibile aDugesia etrusca monoadenodactylaLepori (Turbellaria, Tricladida) nell'Isola di Molara (Sardegna)
The Molara planarian belonging to the groupgonocephalashould not be ascribed to theDugesia benazziiof Sardinia and Corsica, but toDugesia etrusca monoadenodactylafound in the province of Grosseto and described by Lepori in 1947.It was established that the Molara planarian belongs to the above-mentioned race by histological examination of the copulatory system as well as on the basis of its chromosome equipment which is of the 2n=16; n=8 type
Dugesia hepta, nuova specie di Planaria di acqua dolce di Sardegna appartenente alla superspecieDugesia gonocephala(Dugès) (Turbellaria, Tricladida)
A planarian belonging to the groupDugesia gonocephalas.l. was found in thirteen sites in Sardinia (eleven in the catchment area of the Rio Mannu of Porto Torres and two in that of the Coghinas). It is morphologically related toDugesia benazziiLepori of Sardinia and Corsica but presents a different caryotype:
2n=14; n=7 chromosomes instead of 2n=16; n=8 chromosomes. The latter is considered to be the most common in the
superspeciesDugesia gonocephalaof central European and Mediterranean distribution areas.On the grounds of the genomic differences made evident and
its particular distribution in Sardinia, the authors believe that the planarian in question should be considered a distinet species within the groupDugesia gollocephalas.l. and propose the denominationDugesia heptan. sp
Popolamento planariologico dei fiumi del nord Sardegna: 1. I cariotipi delle planarie d'acqua dolce del gruppoDugesia gonocephala(Tubellaria, Tricladida) presenti nel fiume Silis (Sassari)
Karyological investigations were carried out on tail regenerative blastemata of 104 (95 sexual and 9 fissiparous) out of 270 freshwater planarians belonging to theDugesia gonocephalagroup collected at five different sites along the Silis river (North Sardinia).
The results revealed that the SilisDugesia gonocephalas.l. is made up of different karyotypes: (1) diploid karyotype with 14 chromosomes identified asDugesia hepta; (2) diploid karyotype with 16 chromosomes and (3) triploid karyotype with 24 chromosomes, both attributable respectively to the amphimittic diploid and gynogenetic triplo-exaploid biotypes ofDugesia
benazziiLepori; (4) karyotype with 22 chromosomes; (5) karyotype with 32 chromosomes and (6) karyotype with 27 + B chromosomes of fissiparous individuals. The basic haploid set from which the last three types could have derived could not be determined since, although the chromosome number of sets was essentially constant, the composition varied considerably not only between individuals but al so within the same individual
Popolamento planariologico dei fiumi del nord Sardegna: 2. I cariotipi dei tridadi d'acqua dolce rinvenuti nel bacino idrografico del fiume Coghinas
Karyological and karyometric analyses were carried out on freshwater Triclad populations collected in 19 sites of the Coghinas catchment basin (North Sardinia), in order to identify the existing karyotypes and to establish their distribution. By samples collected 25 strains of thegonocephalagroup and 9 of thelugubris-polychroagroup were obtained, on the basis of morphological and reproductive (sexual/fissiparous) caracteristics of the specimens. Within thegonocephalagroup 177 specimens (168 sexual and 9 fissiparous) were examined and 4 karyotypes
were found as follow: l) diploid karyotype with 2n=2x= 14 belonging toDugesia heptaspecies; 2) diploid 2n=2x=16, triploid 2n=3x=24 and aneuploid 2n=?x=32 karyotypes belonging toDugesia benazziispecies. The karyotype with 32 chromosomes, typical of both fissiparous and sexual specimens, is difficult to interpretate owing to the variations in chromosome morphology.
All the karyotypes resulted variously coexisting and distributed.
Within thelugubris-polychroagroup 71 specimens were
examined; 2 karyotypes were identified both diploid with
2n=2x=8 respectively belonging toDugesia mediterraneaandDugesia polychroaspecies
Descrizione di una nuova razza morfologica diDugesia (Schmidtea) polychroa (Turbellaria, Tricladida)della Sardegna
A planarian of theDugesia lugubris-polychroagroup, characterized by triangular head, is reported from Sardinia. The apical position of the eyes is similar to the one found inDugesia (Schmidtea) polychroa. The chromosome set, even if with slight differences, is related to the aforesaid species. Histologieal examination demonstrated its copulatory system to be different, in any detail, from those of the three species oflugubris polychroagroup. The Authors believe that, on the basis of the peeuliarity of both the morphological characters and the chromosome set, the above planarian is to be temporarily considered as a new race of theDugesia (Schimidtea) polychroaspecies.
The denomination they suggest isDugesia (Schmidtea) polychroa macroauriculata
Distribuzione geografica in Sardegna di planarie d'acqua dolce appartenenti alle specieDugesia(S.)polychroaeDugesia(S.)mediterranea(Turbellaria, Tricladida)
Geographical distribution in Sardinia of different karyological biotypes ofDugesia (Schmidtea)polychroaandDugesia(S.)mediterraneahas been investigated.On the whole, 4 biotypes ofDugesia(S.)Polychroa(A, C. D, and A pentaploid biotypes) and 2 biotypes ofDugesia(S.)mediterranea(G, and G triploid biotypes) have been recorded. The A pentaploid and G triploid biotypes were never found in Sardinia
before now.We wish to underline i) the fìnding, in the Temo river, of 5 different biotypes: C, D, A pentaploid ofDugesia(S.)polychroaand G, G triploid ofDugesia(S.)mediterranea; ii) no biotypes ofDugesia(S.)polychroaorDugesia(S.)mediterranea, up to date, have been found by us in the oriental catchment areas of Sardinia
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