Nolana
Nolana coelestis
Nolana is a genus of the nightshade family (Solanaceae ). With 89 species it belongs next to the genera Solanum (Solanum, over 1000 species ), Lycianthes ( about 200 species ), Hammer shrubs ( Cestrum, about 175 species), Bock mandrels ( Lycium, about 83 species) and tobacco (Nicotiana, about 75 species) with the most diverse within the family. Their occurrence is limited to areas in Peru and Chile, a species is endemic to the Galapagos Islands, that is only found there. Mainly due to the fivefold ovary and the resulting collection of fruit not otherwise occur within the Solanaceae family, their taxonomic classification has been controversial for a long time.
- 4.1 External systematics
- 4.2 Internal systematics
Description
Vegetative characteristics
The Nolana species are low growing or prostrate annual or perennial herbaceous plants or woody and semi - woody shrubs. They have a taproot. Often the plant are more or less succulent. The shoot axis grows erect, ascending, decumbent, or countertop, it is hairless hairy to tomentose. In cross-section growth rings are visible.
In periods of extreme drought, the plants make their growth almost completely. However, if they uniformly supplied with sufficient water, many of the rosette- forming species form of an elongated means shoot, which ends in another leaf rosette. In this way the plants can mat-like spread over an area of several meters in diameter.
The leaves are simple and nebenblattlos, may be pedunculated or sessile. They form a rosette and / or are constantly stalk. You are alternate, but arranged almost constantly up against tufted. The leaf blades are entire, fleshy, dorsiventral, ovate to linear or spatulate, occasionally the leaf base runs roughly down to the stem axis. The largest leaves has the kind Nolana rupicola with up to 15 cm long and 10 cm broad leaves. In some cases, the leaf blades are greatly reduced and only made round and linear, then only 1-5 mm long and 1 mm in diameter. These reduced leaves are often densely covered with simple to stellate or branched trichomes which form sometimes glandular tips. Occasionally, some of these peaks are very pronounced salt glands.
Flowers and inflorescences
Some species of the genus bloom very early age, when the plants size is only a few centimeters. The most striking blooms occur in the species complex to Nolana acuminata (corresponding to clade A, compare Internal systematics) on with diameters ranging from 3 to 5 cm. The flowers are typically singly in the leaf axils, rarely racemose inflorescences are formed on ascending, modified branches, where each flower springs from the axil of a circular support sheet.
The five-fold, radial symmetry to zygomorphic flowers are bisexual. Are the flowers zygomorphic, both perianth and the androecium may be ( the totality of all stamens ) or even the androecium asymmetric. The five sepals are the same or different shaped and grown together regularly to almost double lip. They are rarely reduced to a ungelappten tube. The calyx persists on the fruit and encloses them. The crown is funnel-shaped, bell-shaped or tubular, rarely, almost urn- shaped or salverform. The five fused petals are equally diverse and between the Corolla lobe folded, regular or nearly two-lipped. They are blue, purple, lavender or white, the coronary band is dark purple at the base or white and can be pale yellow, white or green stripes have.
The five stamens are faced with the sepals. Three of the stamens have longer stamens than the other two stamens. The stamens are fused at the base with one another and often hairy. The anthers open over inward longitudinal slots. From them the pollen emerges in the form of individual, blue or white, dreifurchigen pollen grains.
The base of the flower is an upstanding, circular, notched or lobed disc, is secreted from the nectar. The ovary consists of five carpels. The stylus is terminal in the subgenus Alona, in the subgenus Nolana he stands on the Fruchtknotenwulst ( gynobasisch ). The scar is little head -shaped and moist.
Fruit and seeds
The fruits of Nolana be interpreted as evolutionarily derived berries. In the subgenus Alona the carpels are united to a most fünfkammerigen (but also three to sechskammerigen ) ovary. The placentation is basal- axial, the ovary develops into a dry fruit of five ( or three to six) mehrsamigen part fruit. In the subgenus Nolana, however, the carpels are strongly lobed, where you can usually find an ovule in each lobe. The ovary in this case evolves into a dry fruit that consists of up to 30 mostly part -seeded fruits. In the seed, there is a curved or screwed embryo.
Other features
The base chromosome number is x = 12 In phytochemical investigations Hydroxyflavonole, quercetin and kaempferol were detected in the plants, substances that are found in other solanaceous plants. In addition, diterpenoids and sesquiterpenoids were found.
Dissemination and locations
The species of the genus Nolana have their distribution areas between the northern Peru and southern Chile, only Nolana galapagensis is endemic to the Galapagos Islands. Most species have a fairly small area, with Nolana adansonii, Nolana gracillima, Nolana Nolana lycioides and jaffuelii are only four species native to a larger distribution area between southern Peru and northern Chile. There can be distinguished two particularly species-rich centers: one in the southern Peruvian department of Arequipa, the other in the north of Chile between Antofagasta and Atacama.
Most species are basic features of the so-called Loma formations - coastal, extremely dry areas, ranging up to an altitude of 1000 m. The formations extend between 5 and 30 ° south latitude over a length of 3500 km and are only occasionally interrupted by river valleys. In some places, the areas are only 25 km wide. The vegetation of these formations is above all dependent on the moisture that gets there from the ocean by fog. In addition, a strong connection with the occurrence of the El Niño phenomenon is observed. The increased moisture that is present during these phases, the otherwise desert-like areas turn into densely vegetated landscapes. The greatest diversity of species of the genus has only a few kilometers developed from the Pacific coast at altitudes between 50 and 600 m. Few Nolana species grow well inland, or at altitudes up to 4000 m.
Ecology
Site observations showed that the flowers are visited by a variety of pollinators, including beetles, butterflies, flies, ants and wasps. The beetle genus Epicante feeds exclusively on Nolana crowns. Presumably, these beetles also act as pollinators. Furthermore, different Thripidae were observed in the flowers.
The dispersal mechanisms of seeds are so far not been thoroughly investigated. It is believed that birds are involved in the propagation and fruits were found in the excretions of rodents.
System
External system
Although Nolana was ruled by several authors from the nightshade family (Solanaceae ), due to their exceptional flowers and fruits ( for example, Hunziker (2001) ), even relatively early molecular studies showed a close relationship to the Bock thorns ( Lycium ). In the 2007 by Richard Olmstead and Lynn Bohs published, several phylogenetic studies summarizing scheme of the nightshade family, the genus next to the goat thorns and the genus Sclerophylax in a group of no rank called " Lyciina " classified. Together with the Tribe Hyoscyameae and the genera Jaborosa and Latua they form a well wrung loose group called " Atropina ", which is placed within the subfamily Solanoideae.
Internal system
Occasionally the genus into two subgenera Nolana and Alona is divided, see especially older edits in the groups also autonomous genres. They differ mainly by properties of the fruit. Phylogenetic analyzes of 63 of the 89 currently recognized species by Dillon et al. (2007), however, showed no significant support for this structure. A group of species within the Nolana, previously part as Sorema Lindl. were separated from the genus, could possibly be given the status of a subgenus.
The phylogenetic studies of Dillon et al. revealed that the species itself is monophyletic and is in turn divided into three monophyletic groups, one of which consists of the sort Nolana sessiliflora and stands as a basal sister taxon to the remaining species. The other two groups are of Dillon et al. clade termed I and II:
Nolana sessiliflora
Clade I
Clade II
Within the clades I and II, a total of eight other monophyletic, with A through H described Unterkladen could be identified, their position within the clades, however, could not be fully understood. Within the clade II could Nolana tarapacana no clade are assigned. A -studied individual of Nolana peruviana was unexpectedly classified in clade H, others expected in clade F.
The five Unterkladen below clade I are formed by:
The three Unterkladen below clade II are formed by:
The species that were not considered in the study were mostly only by the type specimen known endemics, such as Nolana foliosa, Nolana insularis, Nolana pearcei, Nolana platyphylla, Nolana Nolana polymorpha and weberbaueri. Others are probably already extinct due to destruction of the site, such as Nolana minor.
2007 were described by Michael Dilon and his staff further ten species that were not yet part of phylogenetic studies also partly. The newly described species are Nolana aenigma, Nolana arequipensis, Nolana chancoana, Nolana Nolana chapiensis and lezamae from Peru, and Nolana dianae, Nolana reichei, Nolana onoana, Nolana Nolana lachimbensis and philip piana from Chile.
Use
Some species of the genus have limited importance as ornamental plants. Already in 1760 Nolana humifusa was imported from Peru to Europe, occasionally seeds are available in the commercial trade, but no designated varieties are known. The Chilean type Nolana paradoxa has been known since about 1820 from European gardens and is the best known cultivated species, varieties are known, for example, 'Blue Bird' and 'Cliffhanger Blue'.
Botanical history and etymology
The genus was first described in 1762 by Carl Linnaeus jr. His chosen name of the genus is derived from the Latin nola, which means " little bell " means. Placement in a separate family Nolanaceae was proposed in 1820 by Friedrich von Berchtold and Jan Svatopluk Presl, but the genus ordered the systematic treatments of George Don (1838 ) and Michel Félix Dunal (1852 ) respectively to the nightshade family (Solanaceae ) below. George Bentham and Joseph Dalton Hooker placed the species in a tribe within the wind plants ( Convolvulaceae ). Later the species was placed at different position, as his own family Nolanaceae by Arthur John Cronquist (1981) and poor Tachtadschjan (1980 ), or within the Solanaceae as subfamily Nolanoideae or tribe Nolaneae, for example, by Rolf Martin Theodor Dahlgren (1980 ), William D'Arcy (1979, 1991) and Robert follower Thorne (1983). As early as 1992 showed Richard Olmstead and Jeffrey Palmer that Nolana phylogenetically the buck thorn ( Lycium ) is near; this view was rejected by some editors, including Armando Hunziker ( 2001). However, further molecular biological work confirmed this classification.
The internal classification of the genus was often understood very differently; the number of genera and species, in which the now -recognized scope of the genus was divided, was highly variable. Michael Dillon (2007) notes here that systematic treatments that are based only on examination of herbarium specimens, very few species recognize; Researchers who carried out also studies in the field, usually recognized significantly more species. This explains Dillon fact that many properties that allow an Artabgrenzung, are not preserved in Herbarexemplaren. John Lindley (1844 ) recognized five genera ( Nolana, Alonia, Dolia Sorema and Aplocarya ) with a total of 17 species. Michel Felix Dunal (1852 ), the Nolana recognized as a tribe, they also divided into five genera ( Nolana, Dolia Alibrexia, Aplocarya and Bargemontia ) with 33 species. George Bentham and Joseph D. Hooker (1873 ) recognized four genera ( Nolana, Alona, Dolia and Bargemontia ) with a total of 27 species.
The first modern monographic treatment by Ivan Murray Johnston (1936 ) mentions two genera ( Nolana and Alona ) with 63 species. Aldo Mesa, the first filed in 1981, only 18 species in a single genus, and this one hurried to the subgenera Nolana and Alona, expanded his consideration of the genus and recognized in the works of 1997 and 1998, 70 species of. Through extensive research and field work in which new species have been described, currently 89 species are distinguished.