For many years, scientists believed that the plant genus Adenoscadium contained only one species, the rare plant Adenoscadium arabicum, which was first described about a century ago. However, a coincidence led a researcher from the Sultanate of Oman to discover a new, previously unknown sibling of this plant, and she named it after the country, Adenoscadium omanensis, during a study documenting this achievement published in the Edinburgh Journal of Botany.
The story of this discovery goes back to an observation that caught the attention of Dr. Amina Al-Farsi, a plant taxonomist at the College of Science at Sultan Qaboos University, and the curator of the college's herbarium, when she examined samples of the plant "Adenoscadium arabicum" preserved in Omani herbaria, where she found that the plants coming from northern Oman differed in the shape of the leaves and stems from those found in the south of the country.
This observation is not sufficient to conclude that there are two types of plant being mistakenly classified as one plant, as the ripe fruits must be examined, because they are one of the most important characteristics used in classifying plants, and this was the task that Dr. Amina pledged to carry out quickly.
During a research mission in the Hajar Mountains region of Oman, the researcher collected flowering plants and others bearing ripe fruit. Upon careful comparison, it became clear that they had completely different morphological characteristics from the plant "Adenoscadium arabicum," which made her certain that they represented a new species that had not been described before, and she later gave it the name "Adenoscadium ammannissis."
Adenoscadium omannessis is distinguished by its cylindrical fruits covered with long hairs, densely clustered flowers, round leaves, and a length of up to 70 cm, which distinguishes it from Adenoscadium arabicum, which has oval fruits covered with shorter hairs, more widely spaced flowers, diamond-shaped leaves, and a length of up to 50 cm.
Despite the differences in many elements, the fruits of the umbelliferous plants to which the genus "Adenoscadiaum" belongs remain the most important criterion in classifying plants, as scientists liken them to a "human fingerprint." Dr. Amina found that the fruit of "Adenoscadiaum omanensis" differs clearly in shape and internal structure, which confirmed to her that it is an independent species and not just a formal difference within the known species.
The researcher estimates that the rate of spread of the new plant may lead to its classification as “endangered,” according to the standards of the International Union for Conservation of Nature, as there may be less than 10,000 plants in all areas of its spread, and some of the communities studied by the researcher include less than 100 plants, and some of them have less than 20 plants only.
A morphological comparison between the known species "Adenoscadium arabicum" (left) and the new species "Adenoscadium omanensis"
A morphological comparison between the known species "Adenoscadium arabicum" (left) and the new species "Adenoscadium omanensis" (Amina Al-Farsi)
Adaptive and environmental factors
Regarding the reasons that led to the difference between the plant “Adenosiadium amanensis” and its closest known relatives, “Adenosiadium arabicum”, Amina says in statements to Al Jazeera Net: “The climate and the nature of the habitat may be the two main drivers behind the development of the new species, as “Adenosiadium amanensis” thrives in calcareous soils and arid conditions, while the southern species “Adenosiadium arabicum” lives in alluvial soils with tropical conditions.”
Regarding the possibility of its presence in places other than the Hajar Mountains, the researcher explains that "so far, this species is endemic to the Hajar Mountains region of the Sultanate of Oman, and it is possible that some undiscovered groups exist in other places along the coastal mountain slopes with similar topographical features."
Tags:
science
