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Centaurea stenolepis  A. Kerner var. ratezatensis (Prodan) comb. nov. prov.

Flora Europaea           What is "Centaurea ratezatensis Prodan"? This enigmatic taxon is taken as it was described more than 80 years ago from its locco classico  "Fata Fetei above Gura Apelor" (Tarcu Mountains in the "Retezat Group" of the Meridional Carpathians). Now the limestone rocks in the peak of Fata Fetii towering above Gura Apelor - ''Waters Mouth" - a place where three rivers meet covered today by a large dam lake, are a natural reservation and are from far more accessible than in 1925 when the taxon was discovered. Despite this due to the relative difficulty of the genus Centaurea sect. Lepteranthus nobody produced a further analysis, the presence of the taxon within the area was taken for granted and all the considerations were done based on the classic illustrations and descriptions and on the poor available herbarium material. According with these interpretations the taxon was considered variously as a distinct species or a subspecies of Centaurea pseudophrygia or Centaurea phrygia. In September 2010 we made a short trip in the area but the bad weather and the late time hindered us to see more than the low altitude Centaurea individuals from along the road between Netis rivulet and the western tail of the Gura Apelor dam lake. We came back in September 11th 2011 and this time I thoroughly investigated the populations in the area from along the road above the dam (1000-1150m) up to the classic place of the calcareous rocks from Fata Fetii situated at more than 1650 m asl. The facts that we suspected even from the previous year were confirmed. "Legends" about the characters of  Centaurea ratezatensis Prodan: 1. That the long plumose appendages of the involucral bracts are erect or patent and not recurved as in the related species. It is one of the most important characters of the taxon giving to it great distinction from related taxa like Centaurea pseudophrygia  and Centaurea stenolepis. This is completely fake. From along the road near the lake up to high near the limestones of Fata Fetii in between 1150-1550 m asl all the individuals have dense strong recurved appendages which are identical with the ones encountered in Centaurea stenolepis. But go there in a rainy day (a very difficult task due to the tall wet grass and very steep slope) and you will see that all the appendages stand erect. This is a common overlooked feature of the appendages of Centaurea stenolepis: just poor some water over the anthodia of a plant from this species and you will witness this higroscopic effect in a few minutes. We can conclude that Nyarady probably collected the material in 1925 during a rainy day. Due to the pressure in the botanists' press the appendages were forced to remain in an erect position. 2. That the pappus of the achenes is 2 mm long and is half as long as the achene . This is a very rare case. In fact in 547 of the individuals studied (from a total of 550) just in the area of Fata Fetii) it is only around 1 mm long more precisely in between 0.65 and 1.3 mm long. Only 3 individuals have a pappus of 1.85, 1.90 and 2.10 mm respectively. However this would be sufficient to make a distinction between the populations of Fata Fetii and Centaurea stenolepis where the pappus is between 0 and 0.5 mm long in all populations (see also on this site). Unfortunately it remains also the single valid character. 3. That it is an element from the xeric/mesoxeric calciphile vegetation of the alliance Seslerio-Festucion pallentis. The taxon is not present on the sunny calcareous massive rocks from the top of Fata Fetii peak in the typical calciphile vegetation in between 1550-1650 m asl . In fact at around 1475m asl there are some patches of  limestones completely surrounded by tall grass vegetation where some individuals can be found coming from the tall phytocenoses of Deschamsietum caespitosae Hayek et Horvatic 1930 and Digitali ambiguae-Calamagrostietum arundinaceae Sillinger 1933 around where the taxon is abundant and characteristic in between 1150-1500 m asl. From there probably the relevee no. 6 in table 37 pp. 368-369 from Boscaiu N. (1971) - The Flora and Vegetation of the Tarcu, Godeanu and Cernei Mountains (in Romanian) Romanian Academy Press, Bucharest was taken in June 1967 and gave this impression. In fact, if you will travel along the road bordering Raul Mare river between Tarcu and Retezat Mountains you will notice beginning with Gura Zlata chalet to the south individuals of Centaurea belonging to section Lepteranthus which are not rare. You will have to see a plenty if you go a few hundred meters along the concrete secondary road along the Netis creek to the north-west (this is actually the second place from where Centaurea ratezatensis is reported in the literature). Coming back to the main road along Raul Mare river and travelling to south-west to the dam you will find them also along the western tail of the lake as sporadic individuals. If you are familiar with the taxa from Centaurea sect. Lepteranthus in our flora you will remark that all the plants do not resemble phrygia nor pseudophrygia but are in fact identical with stenolepis.  The single noticeable difference will be again the pappus of the achenae, which in most of the individuals is between 0.6-1.3 mm long. The area is placed between 750 and 1150 m asl. Travelling to the west along the western tail of the lake up to its end you will suddenly see in a road curve towering to the north the magnificent white limestone rocks of "Fata Fetii" above the spruce and beech forest. Two distinct abrupt corridors covered with tall grasses like Deschampsia caespitosa and Calamagrostis arundinacea will lead you there after considerable efforts between 1150 and 1650 m asl. Immediately after you enter one of the two corridors you will find plenty of Centaurea sect. Lepteranthus. In the two or three hours you will spend climbing hard through the tall grass and bushes on the steep slope you will get convinced that the plants gradually become smaller and less branched with the altitude and the very variable in size oval anthodia become more and more tightly clustered at the top of the stem. The leaves will become longer, denser and narrower - a sign of the struggle for survival in the dense tall grasses around. If the day and the grasses around there are dry you will remark that the appendages everywhere are all strongly recurved and in no case erect. The pappus of the achenes in almost all individuals however will remain in between the same interval as at the lower altitude, 0.6-1.3 mm long. The individuals are frequent in Deschamsietum caespitosae Hayek et Horvatic 1930, Agrostio tenuis-Festucetum rubrae Horvatic (1951) 1952 and Digitali ambiguae-Calamagrostietum arundinaceae Sillinger 1933. Around 1475 m asl you will find the first patches of limestones with Festuca pallens and some rare individuals of Centaurea sect. Lepteranthus will be also found on them without giving the impression of being characteristic here and not for the phytocenoses of the tall grasses around. Climbing furter you will notice that very small debile individuals are to be found up to the base of the main bulk of limestones but they lack completely in the typical calciphile vegetation of Seslerio-Festucion pallentis from the true steep calcareous rocks. Characters from Centaurea stenolepis: oval small anthodia (average 10 mm diameter, 15 mm long) - in Centaurea pseudophrygia they are globose and larger (average 17 mm diameter and length a character found very rare). Most of the individuals have narrow thin basis of the mid rows appendages and ovate slightly denticulate leaves. Characters resembling Centaurea pseudophrygia: long pappus (average 1 mm - but in no case 2mm !). Some individuals have wide triangular basis in the mid rows appendages and lanceolate clearly serrate dense leaves on the stems. In conclusion, Centaurea ratezatensis Prodan can be considered as a variety of Centaurea stenolepis A. Kerner represented by an isolated population in south-eastern Tarcu Mountains, Romania having the single distinctive characteristic the longer pappus. Being placed in between 750 and 1500 m asl in the grassy glades and corridors around Fata Fetei - Tomeasa peaks the population is affected by clinal altitudinal effects. Apparently Centaurea ratezatensis was described after uncharacteristic individuals (having unusual longer pappus, less branched stems and clustered anthodia at the top of the stem) and in uncharacteristic conditions (wet weather). A thorough extensive and attentive study of the local population would however reveal its clear belong to Centaurea stenolepis. We intend to publish in the near future a thorough scientific study upon this problem. It is sad that strong clear endemics of our flora like Gypsophila petraea, Galium kitaibelianum, Galium baillonii, Centaurea simonkaiana etc or true rarities like Centaurea ruthenica, Serratula wolffii, Pulsatilla patens, Iris pontica, Astragalus exscapus ssp. transsilvanicus, Bulbocodium versicolor, Nepeta ucranica etc receive so little attention and some are even in great danger while we continue to mention in the books describing the flora of our mountains such weak low value taxa like "Centaurea ratezatensis" and "Dianthus henteri". Alexandru Badarau, 12th of September 2011.   The map of the region, satellitary photographs and the known area of the taxon. In the Google Earth photograph below with a pink band are marked over the areas where Centaurea stenolepis typical plants (except for the length of the pappus) can be found on the rocks along the road bordering Raul Mare river and Netis creek. The red bands to the west mark the locco classico of "Centaurea ratezatensis" on the southern steep slope of Fata Fetei peak situated in the grasslands below the massive limestones at the top and along the two steep grassy corridors clearly seen in the image. Here there is an altitudinal cline effect from 1150 up tp 1550 m asl upon the populations of Centaurea stenolepis. The yellow bands are uninvestigated areas where a similar altitudinal cline effect can be found but yet we have no data. The classic description and iconographics of the taxon. The original description of the species. Please remark that the diagnosis asserts that the pappus is as half as long as the achene a fact which is clearly not true when extensively studying the original population from "locco classico"". The original iconography of the taxon from Prodan, I. (1931) - Centaureae Romaniae, Cluj. The anthodia and involucral bracts of the taxon from Prodan, I. (1931) - Centaureae Romaniae, Cluj. Remark the erect-patent appendages as well as in the other figures here. The iconography from Prodan, I and Nyarady, E.J. (1964) - Centaurea L. in Savuleascu, T. - Flora Reipblicae Popularis Romanicae 9, Romanian Academic Press, Bucharest. To the left (no.1) Centaurea pseudophrygia, to the right (no. 2) Centaurea ratezatensis. The treatment of the species from Dihoru, Gh., Parvu, I. (1981) - Endemic Plants in the Flora of Romania (in Romanian), Ceres Press, Bucharest. The "legend" of the erect or patent appendages. In the images below we illustrate an experiment with two individuals from locco classico (Fata Fetei) - in the first instance with dry anthodia and strongly recurved appendages. A few minutes after we poor some water upon them the appendages become erect or patent due to their higroscopic properties. During the rainy days or in the dew rich mornings they always have such a position. Moreover with all the species from Centaurea sect. Lepteranthus with plumose appendages one would obtain the very same effect. We assume that the individuals which served for the description of Centaurea ratezatensis were collected under wet conditions and pressed/dried as they were found. First individual, 1500 m asl. Second individual, 1250 m asl.   Illustrations of the low altitude individuals from Netis creek and along the road bordering Raul Mare river. the achenes of the individuals Illustrations from locco classico: Fata Fetei the achenes of the individuals