kingdom Plantae - plants » divisio Magnoliophyta - flowering plants » class Rosopsida - eudicots » order Malpighiales » family Violaceae » tribus Violeae > genus Viola > Viola sect. Plagiostigma Godr. > Viola subsect. Adnatae W. Becker
Synon.: Viola macroceras subsp. jooi (Janka) Kupffer.; Viola transsilvanica Schur, Oesterr.
Description: Perennial plant with creeping rhizome, without stolons, 5–8 cm high during the flowering and elongating in fruit. Stems absent. Basal leaves of flowering plants are up to 5 cm long and 3 cm wide, extending from the roots, triangular-ovate, cordate-dentate, with a blunt or short pointed tip, with short or fairly deep sinus, on the edge crenate, naked, with long petioles (Figs 6–7). Stipules for almost its entire length adnate to petiole, apex free, linear-lanceolate or lanceolate, acute. Peduncles up to 15 cm long, with bracts 4–6 mm long about middle. Flowers moderate to fairly large, 1.5–2.5 cm long and 1.5–2.5 wide, violet or purplish-violet with dark violet or dark purple stripes (in Serbia white with pale yellow stripes), often yellowish at base, fragrant. Sepals 5–6 mm long, 2–2.5 mm wide, elongateelliptical or ovate-lanceolate, obtuse or rounded at apex, appendages short, obtuse or rounded, glabrous. Petals 10–12 mm long, subrotundate to ovate, ± crenate, lateral bearded. Spur rather slender, scarcely curved upward or almost straight, pale violet or whitish (in Serbia white), 4–6 mm long. Ovary glabrous; style nail-shaped, thickened toward summit. Capsule 7–9 mm long, up to 4 mm wide, ellipsoid, obtuse, glabrous. Seeds large, brown or reddish-brown. Flowering period: April–June.
Distributional Range: Native Europe EASTERN EUROPE: Moldova (possibly), Ukraine (possibly) SOUTHEASTERN EUROPE: Romania (c.)
Habitat: V. jooi grows on limestone rocks and in fissures in mountain regions of the Carpathians. In Romania, it belongs to the group of Dacian phytoelements that inhabit rocky grounds of the alliance Seslerion rigidae Zólyómi 1939, order Seslerietalia Br.-Bl. 1926 and vegetation class Elyno-Seslerietea Br.-Bl. In Serbia (at newly established locality in Mt. Vukan) this plant inhabits rocky grounds community Cephalario-Seslerietum rigidae Tatić et Atanacković 1973 of the alliance Seslerion rigidae Zólyómi 1939, order Seslerietalia juncifoliae Ht. 1930 and vegetation class Elyno-Seslerietea Br.-Bl. 1948. Habitat is surrounded by Moesian types of deciduous thickets and scrubs of Syringo-Carpinetum orientalis (Grebenščikov 1950) Mišić 1967 and Eryngio-Syringetum vulgaris Diklić 1965. This plant grows at the altitude between 780 to 820 m, at S exposure and inclination between 0 to 10o. Geological substrate is limestone.
References:
NIKETIĆ M. et al. Viola chelmea and Viola jooi (Violaceae), new species for the flora of Serbia and their distribution in the Balkan Peninsula and the Carpathians. Bulletin of the Natural History Museum, 2015, 8: 49-74. doi:10.5937/bnhmb1508049N
Viola jooi Janka: a) Mt. Veliki Vukan (NW Serbia) – species habitat; b-c) habitus; d-f) flowers; g) petioles and stipules
Viola jooi Janka – herbarium specimens from Mt. Vukan
Distribution of the species Viola jooi Janka in the Balkan Peninsula and the Carpathians; circle with white spot - according to herbarium new chorological data only; circle with black spot - according to literature data only.