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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

Data from the CHROMREP project led by Marcello Mezzasalma (m.mezzasalma@gmail.com), funded by a Marie Skłodowska-Curie Action. This data was used in the paper: > Marcello Mezzasalma, Jeffrey W. Streicher, Fabio M. Guarino, Marc E.H. Jones, Simon P. Loader, Gaetano Odierna, and Natalie Cooper. Microchromosome fusions underpin convergent evolution of chameleon karyotypes. TBC More details can be found at https://github.com/nhcooper123/chameleon-chromosomes

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

The genus Matoatoa includes two Malagasy endemic species, M. brevipes and M. spannringi. Due to their cryptic behaviour, the two species are known only from a handful of specimens and have been included in few molecular studies. Here we carried out a molecular barcoding analysis using a fragment of the mitochondrial NADH dehydrogenase subunit 2 (ND2) and the first chromosomal analysis of M. brevipes. The molecular analysis confirmed the identity of the studied samples as M. brevipes. However, the level of genetic divergence (4% uncorrected p-distance) between our samples and other sequences of M. brevipes, suggests previously unrecognised diversity within the species. The karyotype of M. brevipes is composed of 2n = 34 chromosomes: the first pair is metacentric, while all the other pairs are telocentric and gradually decreasing in length (Arm Number, AN = 36). C-banding revealed little evidence of centromeric heterochromatin, while NOR-associated heterochromatin was found on the telomeres of a medium sized telocentric pair. No heteromorphic chromosome pairs were found in the karyotype of the species, suggesting that putative sex chromosomes are at an early stage of differentiation. Karyological comparisons with closely related species were performed with Christinus marmoratus, and representatives of the genera Phelsuma, Ebenavia, Paroedura and Uroplatus. Comparisons across genera suggest that chromosome diversification in this group of geckos probably occurred by means of chromosome fusions and inversions, leading to a reduction of the chromosome number and the formation of biarmed elements in different species., Acta Herpetologica, Vol. 15 No. 2 (2020): Acta Herpetologica 15(2) 2020

We conducted a phylogenetic study through karyological data, by standard staining and Ag-NOR banding, and molecular analysis (by 12S and 16S mitochondrial rRNA genes and nuclear gene C-mos) on 11 species of Malagasy geckos, genus Paroedura, and two relatives (Ebenavia inunguis and Uroplatus phantasticus). Ebenavia inunguis and U. phantasticus had 2n = 36 telocentric elements, NORs on the first chromosome pair in E. inunguis, and on the third chromosome pair in U. phantasticus. All examined Paroedura showed NORs on the smallest chromosome pair; moreover, six of the eleven examined species show a 2n = 36 karyotype, with a pair of metacentrics and 17 telocentric pair. The remaining species exhibited karyotypes with a diploid chromosome number ranging from 2n = 31 to 2n = 38. We assume that these karyotype assemblages derived from the 2n=36 karyotype by cryptic and/or simple rearrangements, such as inversions, fissions and fusions. Furthermore, molecular and/or chromosomal data indicate that Paroedura is a monophyletic genus, in which chromosome rearrangements occurred repeatedly and independently during the specific diversification. Moreover both P. bastardi and P. gracilis in current definitions are paraphyletic assemblages of several related species, since their population proves more closely related to P. ibityensis or P. oviceps than co-specific populations.Key words: chromosome, Gekkonidae, Madagascar, Paroedura, molecular phylogeny.

Sexual differentiation (SD) during development results in anatomical, metabolic, and physiological differences that involve not only the gonads, but also a variety of other biological structures, such as the brain, determining differences in morphology, behavior, and response in the breeding season. In many reptiles, whose sex is determined by egg incubation temperature, such as the leopard gecko, Eublepharis macularius, embryos incubated at different temperatures clearly differ in the volume of brain nuclei that modulate behavior. Based on the premise that "the developmental decision of gender does not flow through a single gene", we performed an analysis on E. macularius using three approaches to gain insights into the genes that may be involved in brain SD during the thermosensitive period. Using quantitative RT-PCR, we studied the expression of genes known to be involved in gonadal SD such as WNT4, SOX9, DMRT1, Erα, Erβ, GnRH, P450 aromatase, PRL, and PRL-R. Then, further genes putatively involved in sex dimorphic brain differentiation were sought by differential display (DDRT-PCR) and PCR array. Our findings indicate that embryo exposure to different sex determining temperatures induces differential expression of several genes that are involved not only in gonadal differentiation (PRL-R, Wnt4, Erα, Erβ, p450 aromatase, and DMRT1), but also in neural differentiation (TN-R, Adora2A, and ASCL1) and metabolic pathways (GP1, RPS15, and NADH12). These data suggest that the brains of SDT reptiles might be dimorphic at birth, thus behavioral experiences in postnatal development would act on a structure already committed to male or female.