Petrorhagia dubia 10 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 13 Río de la Miel, Los Alcornocales Natural Park, Andalucía Spain 220413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 14 Río de la Miel, Los Alcornocales Natural Park, Andalucía Spain 220413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 3 Soulia, Crete 110326 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia illyrica 2 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia illyrica 3 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia illyrica ssp haynaldiana 3 Lund Bot Garden 130825 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia illyrica ssp haynaldiana 4 Lund Bot Garden 130825 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 10 Guayadeque, Gran Canaria 080413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 15 near Trujillo SP 140509 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 6 Chio, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 7 Chio, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 9 Guayadeque, Gran Canaria 080413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 13 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 14 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 3 Ölbäck, Endre, Gotland 070604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 4 Ölbäck, Endre, Gotland 070604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 1 Fole, Gotland 980725 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 10 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 14 Le Fontenil N of Briancon FR 150709 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 15 Le Fontenil N of Briancon FR 150709 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 16 Le Fontenil N of Briancon FR 150709 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 2 Copenhagen Bot Garden 130625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 3 Copenhagen Bot Garden 130625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 4 Copenhagen Bot Garden 130625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 5 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 6 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 7 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 8 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 9 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 1 Lastos, Karpathos, Greece 040522 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 11 Río de la Miel, Los Alcornocales Natural Park, Andalucía Spain 220413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 12 Río de la Miel, Los Alcornocales Natural Park, Andalucía Spain 220413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 2 S of Lastos, Karpathos, Greece 040519 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 4 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 5 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 6 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 7 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 8 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 8 near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 9 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia dubia 9 near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia illyrica 1 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia illyrica ssp haynaldiana 1 Lund Bot Garden 130825 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia illyrica ssp haynaldiana 2 Lund Bot Garden 130825 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 1 Chio, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 11 near Trujillo SP 140509 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 12 near Trujillo SP 140509 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 13 near Trujillo SP 140509 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 14 near Trujillo SP 140509 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 2 Chio, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 3 Chio, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 4 Chio, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 5 Chio, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia nanteuilii 8 Guayadeque, Gran Canaria 080413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 1 Peberholm DK 090804 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 10 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 11 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 12 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 2 Peberholm DK 090804 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 5 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 6 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 7 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 8 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia prolifera 9 Kåseberga, Valleberga Sk 190717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 11 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 12 (cult) Brunnby Sk 140717 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Petrorhagia saxifraga 13 Le Fontenil N of Briancon FR 150709 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).