Family Cistaceae Juss.
Сем. LXXXIV. ЛАВДАНОВИ — CISTACEAE JUSS.¹
Fam: Cistaceae Juss.
English Name: Rock-rose or Rock rose family
Shrubs, semi-shrubs or herbaceous plants. The leaves are usually opposite, rarely successive; simple, entire; with or without stipules. The flowers are numerous; in semi-awning to reduced in simple, scorpion-shaped, initially curved apical racemes, rarely paniculate inflorescences, rarely single, apical; correct, bisexual. Calyx usually of 5, rarely of 3 leaflets; loose or both outer leaflets attached more or less to the corresponding inner leaflets; in a bud curved. Petals 5, 3 or missing (sometimes in cleistogamous flowers), free, curved in a bud (in the opposite direction of the sepals), rapidly falling off. Stamens few to numerous, single-row or multi-row, arranged on the disc-like protruding part of the flower bed below the pistil; petioles filamentous, free, usually all with anthers, rarely outer without; anthers lateral or semi-inverted to the pistil, dissolving lengthwise or less frequently with apical rupture. Carpophore composed of 3, 5, rarely 10 fused carpels; the ovary upper, single nested or divided towards the base by intrusive septums into 3, 5 or less often 10 nests, with wall placentas; the style is usually simple, more or less glabrous, disc-shaped or semicircular, less often three-part. Semen numerous to 2 on each wall of the placenta, often on long petioles, usually erect, rarely inverted, drooping. The fruit is a hardened or non-hardened box, cracking into 3, 5 or less often 10 parts; seeds usually small, with or without suture, with endosperm; with more or less curved or folded, less often a straight embryo.
Economic significance. Most of the species can be and many of them are cultivated as ornamental plants mainly due to the large or small (numerous), beautifully colored, more or less aromatic flowers. They are most suitable for rock gardens. Good honey plants. Most of them contain tannins. An essential oil used in perfumery is extracted from Cistus incarius L. All members of the family can be successfully used as soil reinforcers in eroded terrain. Note.
There are many hybrids in nature. Some of the representatives have cleistogamous flowers together with the chazmogamous ones. Cleistogamous flowers differ from chasmogamous only in that the petals are sometimes smaller, thin (almost transparent) or absent; the number of stamens is greatly reduced; the anthers are at the same height as the stigma and stick to it, and with the gradual growth of the ovary the stamens detach from their base. A noticeable external deformity between the cleistogamous and chasmogamic colors is not found in the members of the family spread in the Old World, while in the representatives in America the external dimorphism of the colors is very pronounced.
Table for determination of the genera
1 Petals 16 to 30 mm long, pink, red or white; the box is five-part, with hardened walls …........................... 1. Lavdan - Cistus L.
1* Petals from 3 to 15 mm long, lime yellow, yellow or orange; the box is three-part, with non-hardenen walls ................................ 2
2 Basal leaves in a rosette drying before or during flowering; stigma semicircular, sessile ….............. 4. - Xolanthes (Dunal) Rafin
2* Plants without leaf rosette; the stigma always on a clearly developed style .................................................................................. 3
3 Leaves successive; outer stamen petioles without anthers, stigma trifoliate; seeds with seam .............. 5. - Fumana (Dunal) Spach
3* Leaves opposite; all stamen petioles with anthers, the style head-similar; seeds without seam ...................................................... 4
4 Leaves with stipules; the style short, straight or elongated, slightly ascending ........................................ 2. - Helianthemum Spach
4* Leaves most often usually without stipules, sometimes the upper leaves with stipules; the style at the base is S-shaped or elbow-
shaped …………………...............................................................................................................…………… 3. - Rhodax Spach
¹ Developed by M. Markova.
From: „Флора на Н Р България”, том VII, Изд. на Б А Н, София, (1979)
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The Cistaceae are a small family of plants (rock-rose or rock rose family) known for their beautiful shrubs, which are profusely covered by flowers at the time of blossom. This family consists of about 170(-200) species in nine genera that are not very distinct, distributed primarily in the temperate areas of Europe and the Mediterranean basin, but also found in North America; a limited number of species are found in South America. Most Cistaceae are subshrubs and low shrubs, and some are herbaceous. They prefer dry and sunny habitats. Cistaceae grow well on poor soils, and many of them are cultivated in gardens.
They often have showy yellow, pink or white flowers, which are generally short-lived. The flowers are bisexual, regular, solitary or borne in cymes; they usually have five, sometimes three, petals (Lechea). The petals are free, usually crumpled in the bud, and sometimes in the open flower (e. g. Cistus incanus). It has five sepals, the inner three of which are distinctly wider, and the outer two are narrow and sometimes regarded as bracteoles. The sepal arrangement is a characteristic property of the family.
The stamens are numerous, of variable length, and sit on a disc; filaments are free. The ovary is superior, usually with three carpels; placentation is parietal, with two or more ovules on each placenta. The fruit is a capsule, usually with five or ten valves (three in Helianthemum). The seeds are small, with a hard, water-impermeable coating, weighing around 1 mg.
Recently the neotropical tree Pakaraimaea dipterocarpacea is placed here, following APG IV (2016)
The ability of Cistaceae to thrive in many Mediterranean habitats follows from two important ecological properties: mycorrhizal ability and fast renewal after wildfire. Most Cistaceae have the ability to create symbiotic relationship with root fungi of the genus Tuber. In this relationship, the fungus complements the root system in its task of absorbing water and minerals from the soil, and thus allows the host plant to dwell on particularly poor soils. In addition, an interesting quality of T. melanosporum is its ability to kill all vegetation except the host plant within the reach of its mycelium, and thus to give its host some sort of "exclusiveness" for the adjacent land area.
Cistaceae have also optimally adapted to the wildfires that frequently eradicate large areas of forest. The plants cast their seeds in the soil during the growth period, but they do not germinate in the next season. Their hard coating is impermeable to the water, and thus the seeds remain dormant for a long period of time. This coating together with their small size allows these plants to establish a large seed bank rather deep in the soil. Once the fire comes and kills the vegetation in the area, the seed coating softens or cracks as a result of the heating, and the surviving seeds germinate shortly after the fire. This mechanism allows the Cistaceae to produce a large number of young shoots simultaneously and at the right time, and thus to obtain an important advantage over other plants in the process of repopulating the area.
Molecular analyses of angiosperms have placed Cistaceae within the Malvales, forming a clade with two families of tropical trees, Dipterocarpaceae and Sarcolaenaceae. Recent phylogenetic studies confirm the monophyly of Cistaceae on the basis of plastid sequences and morphological synapomorphies.
Within Cistaceae, eight genera are recognized, including five in the Mediterranean (Cistus, Fumana, Halimium, Helianthemum, Tuberaria) and three in the temperate regions of North America (Crocanthemum, Hudsonia, Lechea). These eight genera can be grouped into five major lineages within Cistaceae:
- a basal clade of the genus Fumana
- the New World clade of Lechea
- the Helianthemum s. l. clade, consisting of the sister groups Crocanthemum and Hudsonia from the New World, and Helianthemum s. s. from the Old World
- the Tuberaria clade
- a cohesive complex of Halimium and Cistus species
From Wikipedia, the free encyclopedia
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Distribution in Bulgaria: (Conspectus of the Bulgarian Vascular Flora) = conspectus&gs_l= Zlc.
References: „Флора на Н Р България”, том VII, Изд. на Б А Н, София, (1979), Wikipedia, the free encyclopedia
Genus Helianthemum Spach - Rock rose, Sunrose or Frostweed
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