Hunting Q’Asam in Northern Oman
By Darrin Duling
24th March, 1996; Sayq Plateau Ridge, Hajar Mountains, Oman:
With my quarry in sight, I stealthily crept through the sweltering, rock-strewn gully, making certain that I did not alert the creature to my presence. Closing in, with my heart pounding, I carefully reached out, all the while recalling the tales of colleagues who had emerged lacerated and bleeding from encounters with members of this group. Realising that I was in an opportune position to strike, I grabbed hold. There was no struggle. In fact, considering the fearsome appearance and robust constitution of this particular specimen, it was surprisingly docile. I spoke softly to it, complimenting on its unique beauty as I snipped samples and dropped them into my collection bag — q’asam was mine at last!
Now before the reader decides to contact the authorities to report me as suffering with `Walter-Mitty Syndrome’, please allow me to explain: Between 22nd March and 5th April 1996, I was in Northern Oman conducting preliminary field research for an M.Sc. Plant Taxonomy thesis project at the University of Reading. My objective was to make morphological observations and collect specimens of a Ziziphus which was believed to be a new, undescribed species. Known by the local people in northern Oman as q’asam, this tree was only recorded from the Hajar Mountains at altitudes above 1,000 metres. The few references about q’asam dubbed it Ziziphus sp. nov, but no one had ever investigated any further to prove this.
I found out about this situation through Dr. Hew Prendergast, of the Centre for Economic Botany at Kew; he had seen this plant during collecting trips to Oman and also believed it to be something completely unique to the region. After examining his and other available herbarium specimens it was apparent that the plant was too under-collected to allow a definite determination of its identity as a new species. With Hew’s encouragement and guidance, I developed an outline for a thesis project researching q’asam and made arrangements with the authorities in Oman for a field trip to collect additional specimens.
My base of operations while in Oman was the capital, Muscat. Upon arrival, I received a warm welcome and generous assistance from officials and staff of the Ministry of Conservation of the Environment, The Oman Natural History Museum and Sultan Qaboos University Department of Biology. Particular mention must be made of the hospitality shown me by Dr. Shahina Ghazanfar and her husband Dr. Martin Fisher, both of Sultan Qaboos University; with their help I was able to quickly orient myself and head out into the field within a few days.
The first time that I saw a living specimen of q’asam I realised that it was indeed morphologically different from the other local Ziziphus species, Ziziphus spina-christi, particularly in its overall habit and the character of its spines and fruit. Another thing which set q’asam apart was the fact that it was found only at altitudes above 900-1,000 metres. I visited four sites within the Hajar Range and found specimens of q’asam in bloom as well as a few which retained fruit from the previous season. Having enjoyed eating the fruit of Ziziphus spina-christi, I was rudely shocked to find the more visually enticing fruit of q’asam to be extremely dry, fibrous and astringent!
This was my only disappointment while in Oman. Throughout my stay I was completely captivated by the dramatic desert landscape and interesting flora. Among the many species encountered were: Moringa peregrina, Calotropis procera, Ebenus stellata, Boerhavia elegans, Schweinfurthia papilionacea, Dyerophytum indica, Nannhorrops ritchieana, Ecbolium viride and Tecomella undulata (the latter being especially striking, with masses of golden-yellow flowers). Other, less common species found at higher elevations presented additional interest in that they are the indicators of an interesting phytogeographical situation: the area which is now the Arabian Peninsula was once completely joined to Africa and Asia, forming a floristic `bridge’ between them. Approximately 12-20,000 years B.P., the peninsula separated from the two landmasses and its climate became steadily warmer and drier. As a result of these changes, relict species with disjunct distributions on both continents were left isolated on the cooler, wetter mountain tops. A few of the most noteworthy examples, with their distributions in parentheses, are: Juniperus excelsa subsp. polycarpos (Hajar Mountains/western Asia), Prunus arabica (Hajar Mountains/western Asia), Sideroxylon mascatense (Hajar Mountains/western Asia/Somalia) and Rhus somaliensis (southern Oman/Somalia). Endemic species have also been recorded from Oman, for example: Anogeissus dhofarica in Dhofar, southern Oman and Caralluma pedicellata in the Hajar Mountains — throughout my research I wondered if q’asam would join these as an endemic species in the north.
At one of the sites visited I encountered an archaeological, rather than botanical, mystery: in the Jabal Bani Jabir, a small range in the eastern Hajar, the mountain tops are dotted with a number of beehive-like stone tombs. Amazingly, these monolithic structures were just recently discovered through aerial photography. Researchers are still puzzling over who built them, why they were built and what building techniques were used? The exact age of these structures is also unknown, with estimates of as much as 10,000 years being proposed.
My last few days in Oman were spent in Muscat sorting out my specimens and taking advantage of a few of the tourist offerings. With so much to hold my interest, it was difficult to leave this newfound paradise, however my mission was completed and I headed back to England. After four months of intensive research involving herbarium/literature surveys, DNA and flavonoid extraction/analysis, I concluded that q’asam was indeed a new, undescribed species of Ziziphus which is endemic to northern Oman! It will be named Ziziphus hajarensis in honour of the mountains to which it is native.
In this limited space it is impossible for me to adequately relate the entire range of my experiences in Oman, or how much I have benefitted from my time there. I enjoyed the privilege of studying in a completely different part of the world and as a result I also made many new friends and valuable professional contacts, both in Oman and the U.K. Certainly my M.Sc. project would not have been so successful, or even possible, without the field observations and specimens gathered in those two weeks.
I am very grateful to the Kew Guild for their generous financial support. I would also like to thank the Bentham-Moxon Trust and The Royal Horticultural Society for their contributions to my expedition.