Chromosome numbers for the Italian flora: 12

In this contribution, new chromosome data obtained on material collected in Italy are presented. It includes the first counts for Hieracium glanduliferum s.str. and H. tenuiflorum, counts for two Armeria species endemic to Italy, and for Onopordum illyricum subsp. illyricum. We also present here the first chromosome count of Allium permixtum for Italy, where this species is known for few localities.

Method. Squash preparations were made on root tips obtained from germinating seeds. Root tips were pre-treated with 0.4% colchicine for 3 hours and then fixed in Carnoy fixative solution for 1 hour. After hydrolysis in HCl 1N at 60 °C, the tips were stained in leuco-basic fuchsine for 7-8 minutes.
Observations. This species is endemic to ophiolitic substrates of western Liguria and Toscana (Arrigoni 2015). The type locality of this species is in Liguria, but very close to the border with Toscana, where the vast majority of populations is found. We report here three counts, one obtained from plants collected in the type locality and two from elsewhere in Toscana. These data confirm the 2n = 18 chromosome number reported for Impruneta, Firenze (Arrigoni et al. 1976(Arrigoni et al. , 1980. This is also the only known number for the entire genus (Rice et al. 2014+).
Method. Squash preparations were made on root tips obtained from germinating seeds. Root tips were pre-treated with 0.4% colchicine for 3 hours and then fixed in Carnoy fixative solution for 1 hour. After hydrolysis in HCl 1N at 60 °C, the tips were stained in leuco-basic fuchsine for 7-8 minutes. Observations. This species is endemic to southern Toscana, and has been only recently described (Selvi 2009). It shows a very narrow distribution range on the surroundings of Monte Labbro (Grosseto). Armeria saviana is morphologically very similar to A. denticulata, from which it can be distinguished for a few leaf and inflorescence features. The chromosome count reported here confirms the previous count published by Selvi (2009) Method. Squash preparations were made on root tips obtained from germinating seeds. Root tips were pre-treated with 0.4% colchicine for 3 hours and then fixed in Carnoy fixative solution for 1 hour. After hydrolysis in HCl 1N at 60 °C, the tips were stained in leuco-basic fuchsine for 7-8 minutes.
Observations. Hieracium glanduliferum subsp. glanduliferum is a south European alpine species with isolated populations that occur in the northern Apennines on Monte Prado, Monte Cusna, and Monte Cimone (Foggi and Ricceri 1989;Gottschlich 2018). This is the first count for this taxon for Italy, whereas other counts have been published for Hieracium glanduliferum Hoppe subsp. piliferum Hoppe ex Nägeli & Peter, for which two different chromosome numbers have been reported so far, 2n = 3x = 27 from Italy, Switzerland, and Austria (Scholte 1977;Chrtek et al. 2009) and 2n = Method. Squash preparations were made on root tips obtained from germinating seeds. Root tips were pre-treated with 0.4% colchicine for 3 hours and then fixed in Carnoy fixative solution for 1 hour. After hydrolysis in HCl 1N at 60 °C, the tips were stained in leuco-basic fuchsine for 7-8 minutes.
Observations. Hieracium tenuiflorum is a south European perennial species (Gottschlich 2018). It was originally described for Monte Bignone, Monte Ceppo, and Monte Arpetta (Bicknell 1896), in the Ligurian Alps. In Italy, this species is widespread throughout the Alps and pre-Alps, but it occurs also in the northern and central Apennines south up to Abruzzo (Bartolucci et al. 2018).
The chromosome number 2n = 3x = 27, reported here for the first time, is consistent with observations made in other taxa belonging to H. sect. Hieracium, such as those of the H. murorum aggregate in Italy (Selvi and Fiorini 1996;Geraci et al. 2007) and Europe (Chrtek et al. 2009).
S. Orsenigo, B. Cera, A. Giacò Method. Squash preparations were made on root tips obtained from germinating seeds. Root tips were pre-treated with 0.4% colchicine for 3 hours and then fixed in  Carnoy fixative solution for 1 hour. After hydrolysis in HCl 1N at 60 °C, the tips were stained in leuco-basic fuchsine for 7-8 minutes.
Observations. This species occurs in southern Europe, from the Iberian Peninsula to the Balkans, in Turkey, and in Syria (Greuter 2006+). Although several chromosome counts are available in the literature (Moore and Frankton 1962;Chuksanova et al. 1968;Valdes 1970;Kuzmanova et al. 1979;Snogerup 1995), no data have been published so far for Italy, where two subspecies can be found, i.e., O. illyricum subsp. illyricum, distributed throughout south-central Italy (including Sardegna and Sicilia), and O. illyricum subsp. cardunculus (Boiss.) Arènes, which is known only for Sicilia (Bartolucci et al. 2018). We confirm here the chromosome number 2n = 34 previously reported for the species.