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This work is one of the first studies on the growth of Poecilia latipinna outside its natural habitat. The objective of our study was to investigate the growth parameters of the population of P. latipinna, which is an alien species in Oman (Wadi Al-Bahayes). The population structure of P. latipinna in Wadi Al-Bahayes (Oman; 23°40′47″N; 58°11′36″E) was studied in June and August 2020, using 124 fish. In the course of this study, the number of individuals of each sex, age, weight and size composition were determined. In addition, the total length–weight relationship (LRW) was calculated, as well as the von Bertalanffy growth equation. The mean growth performance (phi prime) and the condition factor were calculated. Males accounted for 37.10% and females for 62.90% of the population. The length–weight relationship and the von Bertalanffy growth equation were W = 0.0214 × L2.7889 R2 = 0.9212, Lt = 11.46 (1 – e−0.127 (t + 2.71)) for males and Lt = 14.51 (1 – e−0.072 (t + 3.98)) for females. The mean growth performance and the condition factor were calculated as 1.22 for males and 1.18 for females and 1.54 for all specimens.
This paper reports briefly on the results of a short reconnaissance at the site of Qumayrah–Ayn 2 (QA 2), a new prehistoric site located in a poorly studied part of the Qumayrah Valley in northern Oman. A survey and limited probing by the Omani–Polish Qumayrah Archaeological Project confirmed the presence of a sediment, approximately 15–20 cm thick, which yielded not just lithics, but also stone installations discovered in situ. One of these installations was evidently a hearth, the other a kind of platform. The lithic assemblage is characterized by a prevalence of flake technology with rare blade products. Predominant in the tools group are side-scrapers, notches and perforators produced by direct-scaled retouch. The most characteristic tools are tanged projectile points made on flakes. The main problem is contextualizing these materials. On the grounds of certain premises they may be associated with the Fasad technocomplex, but not necessarily the pre-Neolithic one as is the case of the classic types. However, a much later chronology is also quite possible.
The preliminary results of a comprehensive survey of Sīnīya Island in the Khawr al-Bayḍāʾ of Umm al-Quwain are presented here. The onset of human occupation remains to be confirmed, with scarce evidence for limited activity in the late pre-Islamic period (LPI, c. 300 BC – AD 300). The first major phase of occupation dates to the seventh and eighth centuries (early Islamic period) when a monastery and settlement were established in the north-east of the island. Probably the peak occupation falls between the fourteenth and fifteenth centuries, when the stone-town of Old Umm al-Quwain 1 was built, followed by the eighteenth to early nineteenth century when the settlement moved to neighbouring Old Umm al-Quwain 2. The town was destroyed by the British in 1820 and moved to the facing tidal island, where Old Umm al-Quwain 3 (the modern city of the same name) developed. This resulted in an emptying of the landscape, and Sīnīya Island was little visited in the nineteenth and twentieth centuries, except for the estate of the ruling Āl Muʿallā represented by the Mallāh Towers.
A recent study proved that Aynuna has been settled since at least the Hellenistic period and was the major settlement on the Arabian coast of the northern Red Sea in the Nabatean/Roman period, serving as the port of Petra. Scientific literature is mostly concerned with the identification of Aynuna with ancient Leuke Kome, leaving aside the later history of the site. In the late Roman/Byzantine period its significance as a trade centre slowly diminished, although it might have remained a tax collection point. In the early Islamic period, Aynuna served as a local agricultural centre and war port for the Arabian forces conquering the Eastern Desert. Later on, accessibility of fresh water made it a stop on the Egyptian Hajj Route, and antique Aynuna/Leuke Kome finally became Islamic ‘Aynūna. This paper aims to present a diachronic analysis of the changing functions of the site using published archaeological reports and Arabic written sources.
Physiological adaptation to arid environments in many desert succulents involves crassulacean acid metabolism (CAM) with modified photosynthetic carbon acquisition aimed at improving water use efficiency. The leafless perennial Caralluma acutangula is an abundant stem succulent in the arid regions of subtropical zones of the Arabian Peninsula. These arid regions southwest of Saudi Arabia are characterized by a short three months wet season (June–August) and a long dry season. The wet season is characterized by high temperature, high evaporation, and strong sand storms. Research presented in this paper involved water status, diffusive conductance, and crassulacean acid metabolism (CAM) of both seedlings and mature C. acutangula plants growing under natural conditions. Plant water status was determined by monitoring changes in stem water content, diffusive conductance was monitored using porometry technique, and CAM was detected by determining chlorenchyma titratable acidity. Seedling establishment of C. acutangula takes place in the short wet season during which seedlings depend on the high productivity C3 mode of photosynthesis. Mature plants are obligate CAM plants exhibiting this mode of carbon fixation during both the wet and the dry seasons. As the dry season progresses dampening of CAM acidification-deacidification cycles and low stomatal conductance denote the switch of mature plants from CAM to CAM-idling in response to protracted water stress. Our results show that the C3 mode of photosynthesis in C. acutangula seedlings during early ontogeny is due to exposure of seedlings to suboptimal irradiance in the shade of other plant species at the study site. This C3 mode of photosynthesis is beneficial for fast seedling establishment. Our results also show that the shift from CAM to CAM-idling in mature C. acutangula plants occurs in response to protracted water stress, which is favourable for survival of this succulent in its inimical arid habitat.
Cossyphodes asiricus sp. nov. is described from an isolated relict mountainous forest in the Asir Mts. in south-western Saudi Arabia. This myrmecophilous species was found in a debris chamber of a Pheidole ant nest. It differs from the Palaearctic and adjacent Ethiopian congeners mainly by the development and orientation of the pronotal and elytral keels. Paramellon sociale was collected on the eastern side of the Arabian Peninsula in the United Arab Emirates in a completely different, but not isolated, and distinctly drier habitat. Both species are photographed, the localities are mapped, and some notes on biology and ecology are given.
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