Jordan: Kickxia petrana and Dana plants

Published: May 30th, 2010 | Updated: 17/01/15

The most important source of species new to science that I obtained for study, before the signing of the peace agreement between Israel and Jordan, continued to be the dried speciments collected in Edom by Mrs. Ingrid Kuenne Discovering two new species of Kickxia, in Sinai and in the Judean Desert, made me suspect that the Kickxia in Ingrid’s collection was also a new species (Fig. 12.1.1). In one of her specimens of that species there were ripe seeds. Checking up on the 0.5-0.6 mm long seeds revealed a strange hair-like growth on the seed surface. Michael Dvoracheck, as always, helped me in producing SEM images of the seeds (Fig. 12.1.2). I was very happy to see these minute emergences on the seed surface. Such “thorns” are not seen on other species to which I had access.

Around 1991 two international scientific events, related to the genus Kickxia, took place. A PhD student, in Germany or in Austria, concluded that the genus Kickxia should be divided into three genera. She thus disregards decisions or suggestions made by other researchers (including my own). A book written by a British author shortly after the publication of that doctorate, dealt with all known species of Linaria and Kickxia. This monographer upheld the results of my former investigations. I followed other international bodies in recognizing the British perception. I felt I should describe the new Kickxia and name it after the area of its origin – Petra, (Kickxia petrana). It is confined to rocks and so far I have found it in hard sandstone and limestone outcrops. An easy place to reach is the limestone cliffs near Dana Visitor’s Center. Many specimens are confined to cracks of the hard limestone boulders that function as a natural gateway between the ancient village of Dana and the Visitor’s Center.

Fig. 12.1.1: Kickxia petrana in a crevice of red sandstone in Petra.

Fig. 12.1.2: A seed of Kickxia petrana (0.5 mm long) as seen with scanning electron microscope.

Rubia danaensis, Micromeria danaensis and Silene danaensis

I visited Jordan and traveled from Amman to Dana with Tarek who was director of Dana Nature Reserve.During the three-hour drive through the desert I gave Tarek, schooled in Humanities, my view on desert botanical investigations, so that we could build a research system for future work together. On the way, shortly afterwards, joint investment of our efforts paid off, when Tarek translated into Arabic my English lecture to the inspectors of the Jordanian Nature Reserves Authority in the area. Tarek translated my presentation as if he had been my research partner for many years. Arriving at Dana with Tarek, we found that I would have to wait a day or so until Dr. Abdelkader Bensada, who was to accompany me, arrived from another mission. Meanwhile I went to study the limestone cliffs near Dana Visitor’s Center. I found there a Silene species with sticky stalks that resembled the stems of Silene swertiifolia (Fig. 12.1.3) known from the Judean Mts. and the Galilee. The Silene found in Dana was not yet in bloom and kept its identity secret. Green tufts, that were difficult to identify (Fig. 12.1.4), were hanging from the cliff fissures. I threw some stones and soon had in my hands stems, leaves and flowers (Fig. 12.1.5). The plant reminded me of Rubia tenuifolia but differed in several features. Later I found in Dana Reserve delicate stems bearing small pink flowers, growing between the bushes of Origanum petraeum and Polygala negevensis. All were confined to hard white sandstone. I picked up a few stems and dried them in a page from my notebook, which I kept in my shirt pocket, close to my heart.

The plant reminded me of Micromeria serbaliana that I discovered in Sinai but differed considerably. Later that year, I succeeded in visiting there again, and collected blooming Silene for documentation of the “type” material. Additional specimens of the new Rubia and Micromeria were collected as well. A study of specimens of the three species from Dana, with literature and herbaria, increased the possibility of their being worth describing as new to science. Consultation with the experts abroad verified that they were new. As no researcher had yet named a plant after the name of Dana I named the three of them after the site of their discovery: Silene danaensis, Rubia danaensis and Micromeria danaensis.

Fig. 12.1.3: Silene swertifolia blooming at the beginning of summer in Jerusalem.

Fig. 12.1.4: A shrub of Rubia danaensis hanging from a cliff near the Visitor’s Center of Dana Nature Reserve.

Fig. 12.1.5: Blooming branches of Rubia danaensis. Leaves are narrow and linear.

Rubia danaensis differs from the widely distributed Rubia tenuifolia by the hooked small teeth present in the latter and absent in the former. R. tenuifolia is a vine of the maquis and the hooked teeth (Fig. 12.1.6) assist the climber in holding onto adjacent plants nearby. However, R. danaensis is confined to cliff-tops and the missing teeth do not assist or disturb its life style. The flowering and fruiting seasons differ for populations growing close to each other (Figs. 12.1.7, 12.1.8). My decision to publish it as a species new to science was supported by the anonymous reviewer of my article (Fig. 12.1.9). I later saw that R. danaensis grows on additional limestone cliffs north and south of Dana Nature Reserve.

Fig. 12.1.6: Rubia tenuifolia, which has hooked stiff teeth at the leaf margin.

Fig. 12.1.7: Rubia danaensis with young fruits.

Fig. 12.1.8: Rubia danaensis with ripe fruits.

Fig. 12.1.9: Rubia danaensis as drawn for the article where it is described for the first time.

The Silene from Dana seems to be a relative of S. swertiifolia which grows in the Judean Mts. and Samarian Mts. (Fig. 12.1.3), of [“Silene libaotica” S. libaotica] which grows on Mt. Hermon (Figs. 12.1.10, 12.1.11), and of S. schimperiana (Figs. 12.1.12, 12.1.13) which grows in Sinai. These species resemble each other in the stem morphology, but differ considerably in their flower size. An article describing it in English and Latin was published in an international journal. In later excursions to SW Jordan we found that the Silene has the largest distribution area among the three “Dana species.” Blooming specimens were found in the sandstone landscape of Jebel Umm Adami, the highest mountain in Jordan. A search is likely to lead to the discovery of this species in Saudi Arabia (limestone and sandstone cliffs; Fig. 12.1.14).

Fig. 12.1.10: Silene libanotica on Mt. Hermon.

Fig. 12.1.11: Silene libanotica on Mt. Hermon.

Fig. 12.1.12: Silene danaensis as drawn for the article where it is described for the first time.

Fig. 12.1.13: Silene danaensis growing in rock crevices in Edom (SW Jordan).

Fig. 12.1.14: Distribution map of a few closely related Silene species in the Near East: asterisk – S. danaensis; triangle – S. schimperiana; square – S. swertifolia.

Small pink flowers of Micromeria danaensis (Fig. 12.1.15) were carried gently on delicate stems between the stems of other plants growing in the same crack. I did more tours in Dana Reserve (definitely not enough) and found only one more population of that species. Ironically, when I visited the Dana reserve about ten years after describing the plants carrying the name of Dana, there was no longer anyone there who knew me and my work. After declaring that I am a botanist, the man there was happy to inform me that the workers of Dana Reserve had managed, at last, to find Micromeria danaensis (Fig. 12.1.16). I let him be happy and did not ask about Silene danaensis and Rubia danaensis.

Fig. 12.1.15: Micromeria danaensis in bloom.

Fig. 12.1.16: Micromeria danaensis as drawn for the article where it is described for the first time.