Tigris Basin Research Articles

Role of the East Asian trough on the eastern Mediterranean temperature variability in early spring and the extreme case of 2004 warm spell

This study investigates the potential influence of the East Asian trough (EAT) on the eastern Mediterranean temperature variability in early spring. In connection with this, it also examines the extreme case of the year 2004 when anomalous warming of the eastern Anatolia resulted in unprecedented snowmelt runoff amounts in the Euphrates and Tigris basins in early March. In the analyses, we used reanalysis data, gridded products of surface temperature and snow cover, river discharge data and satellite imagery. We employed an intensity index for the EAT and a trough displacement index for the Mediterranean trough (MedT) to explore the relationship between the strength of the EAT and the displacement of the MedT at pentad resolution. Our analysis shows that there are statistically significant correlations (at 99% confidence level) between the strength of the EAT and the zonal shift of the MedT on some pentads (e.g., 3rd, 13th, 37th and 59th), but that the highest correlation occurs on the 13th pentad of the year corresponding to the early days of March. It seems that, on this pentad, when the EAT is strong, the MedT tends to be located in the west of its climatological position (about $$30\hbox {$-$}35^{\circ }\hbox {E}$$ ) which causes warmer conditions over the eastern Mediterranean. In 2004, which appears to be an extreme year for this phenomenon, the MedT is positioned and deepened in the central Mediterranean (about $$10\hbox {$-$}15^{\circ }\hbox {E}$$ ), and extended towards central Africa during the early days of March. This synoptic pattern provided favorable conditions for the development of a tropical plume/atmospheric river with a southwest-northeast orientation, carrying warm tropical African air towards the eastern Mediterranean and Anatolian highlands resulting in rapid melting of the snowpack as well as severe precipitation, and thus flooding events, in the eastern Anatolia. A key finding in our analysis is that the strengthening of the EAT was instrumental to the increased amplitude of the ridge-trough system over the Euro-Mediterranean region in the early days of 2004 spring. We highlight that the response of surface and upper level meteorological conditions to the amplitude of the ridge-trough system enhanced by the strength of the EAT might be crucial in the understanding of some of the extreme hydrometeorological events in the eastern Mediterranean region.

A 40-Year Analysis of the Hydrological Drought Index for the Tigris Basin, Turkey

Drought is a natural disaster that occurs globally when water availability is significantly below normal levels. Drought assessment is important for water resource planning, and therefore indexes can be used to characterize drought magnitudes. Using the monthly streamflow data at 47 stations from 1972 to 2011, the streamflow drought index (SDI) series with 3- (SDI-3), 6- (SDI-6), and 12-month (SDI-12) time scales were calculated, and the hydrological drought of the upper Tigris Basin in Turkey has been assessed. The results showed that almost all stations experienced at least one severe drought during the study period. The results revealed that since the early 1990s the study area has become drier. Using the data for a 12-month period and the area of the sub-basins for each flow monitoring station, area-weighted SDI-12 (WSDI) values were constructed. According to the WSDI results, the intensity and number of drought conditions increased during every 10-year period. This outcome has been verified using the maps of averaged SDI-12 values over the Tigris Basin. We noticed from observations of the maps that the time domain zones in lower latitudes experienced drought earlier as compared with zones in higher latitudes.

Preliminary Assessment of Hydrothermal Risks in the Euphrates–Tigris Basin: Droughts in Iraq

This paper presents a temporal and spatial pattern of precipitation, surface air temperature, and drought occurrence in Euphrates–Tigris rivers basin with special emphases on Iraq. Historical records based on 115 years (1900–2014) of monthly precipitation and temperature data has been divided into four sub-periods, each of 30 years (first 1900–1929, second 1930–1959, third 1960–1989 and fourth 1985–2014) and studied separately. The results showed that the mean annual precipitation in Iraq for the four sub-periods is: 218.5, 202.1, 196.4, and 174.9 mm respectively, with an average of 198 mm. This indicates that the mean annual precipitation decreased by 43.6 mm (20 %) in the fourth sub-period compared to the first sub-period. The mean annual temperature for the four sub-periods in Iraq are 22.0, 21.9, 22.0, 22.8 °C respectively, with an average of 22.2 °C. This indicates that the average monthly temperature during the year in Iraq increased by 0.76 °C (3.45 %) in the fourth sub-period compared to the first sub-period. The probability of occurrence of dry (hot) periods in Iraq increased by 345.5 % (147.7 %) in the fourth sub-period compared to the first sub-period. Fortunately, the greatest drought occurrence is observed in western parts of Ira, where agriculture is irrigated, in rain-fed areas in the northern Iraq, there has also been a decrease in precipitation, but not so strong as in the west of the country. A preliminary conclusion about the current climatic desertification and its possible consequences for Iraq was drawn.

Environmental sensitivity to desertification in northern Mesopotamia; application of modified MEDALUS by using analytical hierarchy process

Poor management, low vegetation cover, and severe erosion are undermining the stability and sustainability of lands. In this study, modified Mediterranean Desertification and Land Use (MEDALUS) method was used to identify environmentally sensitive areas (ESA) to desertification in Tigris Basin, Turkey. Soil samplings (0–20 cm) and field observations were conducted within 3.752 km2 land. Biophysical and anthropogenic parameters of sampling locations have been integrated and processed by geographic information systems obtaining soil, climate, vegetation, and management quality indexes. Additional six parameters for soil quality and one for management quality were used to adopt MEDALUS to the context of Tigris Basin. The weights for parameters and indicators were calculated using analytical hierarchy process (AHP). Tigris Basin was classified into one fragile and two critical areas using original method, whereas one fragile and three critical classes were defined with the modified method. In the original method, fragile areas represented 5.65% and low-degree critical areas 24.49% and moderate critical areas 69.86% of the study area, which are needed to be monitored for severe land degradation. Modifying MEDALUS allowed to define highly critical areas (51.41%) which have not been detected in the original method. The critical areas are primarily used for field crops with extensive tillage, medium degree of plant cover, low drought resistance, and erosion along with low management quality due to the lack of required environmental protection. The results revealed that adaptation of new parameters and weighting in MEDALUS improved the ability of classifying ESAs for a regional scale to desertification.

Characterizing Spatial Variability of Soil Properties in Tigris Basin Using Geostatistics and Geographical Information Systems

Toprak özelliklerinin mesafeye bağlı değişkenliklerinin belirlenmesi, incelenmesi ve haritalanması yoğun tarımsal üretim yapılan arazilerde uygun amenajmanların geliştirilmesi ve üretimin sürdürülebilirliğinin sağlanması açısından son derece önemlidir. Bu çalışmada ülkemizin su rezervlerinin büyük bir kısmının yer aldığı, önemli sulama projelerinin gerçekleşmekte olduğu Dicle Havzası’nda bir kısım fiziksel ve kimyasal toprak özellikleri belirlenmiş, mesafeye bağlı değişkenlikleri modellenmiş ve haritalanmıştır. Toprak örneklemeleri, Diyarbakır ile Siirt illeri arasında 5 x 5 km gridlere ayrılmış 4.341 km2’lik alanda her gridin yaklaşık köşesinden toplam 175 noktada 0-20 cm derinlikten alınmıştır. Toprak özelliklerinin 5 km’den kısa mesafelerdeki değişimlerinin daha doğru tahmin edilebilmesi amacıyla ardışık iki gridin köşe noktaları arasında 250 m, 750 m ve 1750 m mesafelerden de 33 toprak örneği alınmıştır. Alınan bozulmuş örneklerin tekstür (kum, kil ve silt), organik madde, kireç, toprak reaksiyonu, elektriksel iletkenlik, alınabilir fosfor ve potasyum analizleri yapılmıştır. Mesafeye bağlı değişkenliğin modellenmesi ile örneklenme yapılmayan noktaların ilgili özellikleri tahmin edilmiş ve yersel değişim haritaları oluşturulmuştur. Çalışma alanında en düşük değişkenliğin pH (% VK= 3.9) ve en yüksek değişkenliğin ise alınabilir fosfor (% VK= 137.77) konsantrasyonunda olduğu görülmüştür. En yüksek range değerine sahip toprak özelliği elektriksel iletkenlik (135.4 km) iken en küçük range değeri pH (4.74 km) için elde edilmiştir. Her bir özelliğin en düşük ve en yüksek olduğu yerlerin rahatlıkla tespit edilebildiği toprak haritaları, uygun amenajman yöntemlerinin belirlenmesi, sorunların giderilmesi ve girdilerin en uygun kullanımı açısından son derece yararlı araçlardır.

Length-weight and length-length relationships for three species of Squalius (Cyprinidae; Leuciscinae) from the Caspian Sea, Namak and Tigris basins of Iran

Length-weight and length-length relationships were estimated for three species of the genus Squalius. These fish were sampled from the Caspian Sea as well as the Namak and Tigris basins of Iran. Sampling took place between July 2009 and August 2010 using a seine net (15 m long, 2 m width and 5 mm mesh size). The values of the b parameter in the length-weight relationship equations were determined as 3.37 for S. turcicus, 3.25 for S. namak and 3.14 for S. berak (b > 3).

Morphological variations of Alburnus mossulensis (Heckel, 1843) populations in Iran

Morphological variation of Alburnus mossulensis (Heckel, 1843) populations in Iran were investigated by collection of 705 specimens from 27 rivers of five basins, including Bushehr, Fars, Karkheh, Karun and tributaries of Tigris (Diyala) basin in Iran in 2010 by a seine net. The specimens were fixed in 10% formalin for further investigation after anesthetizing in 1% clove oil solution. Twenty-two morphometric and 11 meristic characters were examined. Morphometric characters in adjusted form and meristic characters in classified form were used for population comparison. Analysis of morphometric and meristic characters by ANOVA showed significant differences (p<0.05) in all basins for all characters except the number of dorsal and anal fin spines. Classification of meristic characters showed most specimens of all basins have eight soft rays in dorsal fin, 12 soft rays in anal fin, 19 soft rays in caudal fin, 15 soft rays in pectoral fin and nine soft rays in pelvic fin. Discriminant function analysis showed that populations from Fars and Karun Basins were different from each other and from other populations, on the other hand, populations from Diyala, Karkheh and Bushehr basins overlapped. This result may indicate that there are similar conditions in Diyala, Karkheh and Bushehr basins, resulting in more similarity amongst the populations of these basins.

Calipso recordings and monitoring dust storms over the open seas in south of the iran plateau

Open seas in the south of the Iran plateau are under the influence of heavy dust storms which are originating either from the Tigris and Euphrates basin, the Arabian Peninsula or Hamoun lake. We have used the recordings of the CALIPSO satellite to investigate the seasonal variations as well as the origins of the dust storms over the region. CALIPSO data set shows dust activities are frequent during May to September in the interested region and the Hamoun lake has considerable impacts on it.

Hydrochemical characteristics of surface and groundwater and suitability for drinking and agricultural use in the Upper Tigris River Basin, Diyarbakır–Batman, Turkey

Investigations were undertaken into the quality of surface water and groundwater bodies within the Upper Tigris Basin in Turkey to determine their suitability for potable and agricultural use. In the study area, the majority of the groundwater and surface water samples belong to the calcium–magnesium–bicarbonate type (Ca–Mg–HCO3) or magnesium–calcium–bicarbonate type (Mg–Ca–HCO3). Chemical analysis of all water samples shows that the mean cation concentrations (in mg/L) were in the order Ca2+ > Mg2+ > Na+ > K+ and that of anions are in the order \( \text{HCO}_{3}^{ - } \) > \( \text{SO}_{4}^{2 - } \) > Cl− > \( \text{CO}_{3}^{ - } \) for all groundwater and surface water samples. The Mg2+/Ca2+ ratio ranges from 0.21 to 1.30 with most of the values greater than 0.5, indicating that weathering of dolomites is dominant in groundwater. The analysis reveals that all of the samples are neutral to slightly alkaline (pH 7.0–8.7). Groundwater and surface water suitability for drinking usage was evaluated according to the World Health Organization and Turkish Standards (TSE-266) and suggests that most of the samples are suitable for drinking. Various determinants such as sodium absorption ratio, percent sodium (Na %), residual sodium carbonate and soluble sodium percentage revealed that most of the samples are suitable for irrigation. According to MH values, all of the well water samples were suitable for irrigation purposes, but 80 and 81.82% of Zillek springs and surface water samples were unsuitable. As per the PI values, the water samples from the study area are classified as Class I and Class II and are considered to be suitable for irrigation.

Geometric morphometric comparison of trout barb, Capoeta trutta (Teleostei: Cyprinidae) in the Tigris River basin

A total of 136 specimens of trout barb, Capoeta trutta (Heckel, 1843) from eight rivers of the Tigris Basin were caught by seine net to compare their shape using geometric morphometrics. After anesthesia, using 1% clove oil solution, the specimens were fixed in 10% buffered formalin and transferred to the Ichthyology Museum of Isfahan University of Technology for further studies. The left sides of the specimens were photographed using a copy-stand equipped with a digital camera. To extract body shape data, 13 homologous landmark-points were digitized using tpsDig2 software. After GPA superimposing, the landmark data, were analyzed using Principal Components Analysis (PCA), Canonical Variate Analysis (CVA) and Cluster Analysis (CA) to explore the patterns of variation in their body shape. All multivariate analyses were computed using PAST software. The consensus configuration of populations was visualized using the wireframe graphs in MorphoJ to compare their shape difference. The PCA, CVA and CA showed differences among the populations, especially, between Konjancham and other populations. This result showed that geometric morphometric methods could separate trout barb populations of the Tigris River Basin from each other to a great extent. Potential factors contributing to the observed variations include differences in physicochemical parameters of rivers and geographic distance among the populations. However, for more details, molecular studies are needed.

The distribution of Acheulean culture and its possible routes in Turkey

Turkey is a country located at the crossroads of possible migration routes between three continents and, as such, it plays a pivotal role in the distribution of Acheulean culture in Eurasia. Although Acheulean culture, which is considered to have reached Turkey via the “Levantine corridor”, shows a wide distribution in the Turkish Anatolian side, it is not found in the Thrace part of Turkey. Therefore, the spread of Acheulean culture from Turkey towards the Balkan Peninsula, i.e., in southeastern Europe, via the Thrace region of Turkey is not considered. However, the cultural artifacts of Acheulean culture are often found in eastern and southeastern Anatolia. The Acheulean cultural artifacts, especially bifaces, found in the open-air sites settled on the old river terraces – generally in the Euphrates and Tigris Basin – are strong indications of the distribution of Acheulean culture in Anatolia as well as the possible migration route of Homo erectus from Anatolia to the Caucasus. Many Acheulean sites recently identified in the Caucasus seem to support such a distribution as well. This paper discusses the distribution of Acheulean culture and possible routes spreading into Turkey according to the geographic regions.

Reproductive biology of Mossul bleak (Alburnus mossulensis) in Bibi-Sayyedan River of Tigris basin in Iran

Reproductive characteristics of Mossul bleak, Alburnus mossulensis, a native species of Cyprinidae family in Bibi-Sayyedan River of Semirom, Isfahan, were investigated by monthly sampling during December 2010 to December 2011. Five hundred and fourty three specimens (256 females, 159 males and 31 immature) were caught by a sein net (5 mm mesh size). The collected sampeles were anesthesized in 1% clove oil solution and transported to the laboratory on ice and subjected to dissection and biometric measurments. Age of males and females ranged from 0+ to 5+ years. The sex ratio was 1M: 2.2F (p < 0.05). The females outnumbered the males in all age classes. The largest female was 16.8cm in total length and 49.12g in weight and the largest male was 14.1cm in total length and 28.19g in weight. The age and total length at first maturity of females and males were estimated as 1 year and 5.3cm total length, and 2 years and 4.4cm, respectively. The minimum, maximum, and avarge absolute fecundity were 2064, 10316, and 5505 ± 2686SD, respectively and also, the relative fecundity was 203 ± 58 egg/g body weight. Macroscopic analysis of gonads and gonadostomatic index (GSI) values suggested that spawning ofA. mossulensis occurs from March to June with a peak in April. Thus, A. mosullensis is considered a group-synchronous type species with a capacity for multiple ovulations within a reproductive season (multiple spawner).

Soil Moisture Estimation over Vegetated Agricultural Areas: Tigris Basin, Turkey from Radarsat-2 Data by Polarimetric Decomposition Models and a Generalized Regression Neural Network

Determining the soil moisture in agricultural fields is a significant parameter to use irrigation systems efficiently. In contrast to standard soil moisture measurements, good results might be acquired in a shorter time over large areas by remote sensing tools. In order to estimate the soil moisture over vegetated agricultural areas, a relationship between Radarsat-2 data and measured ground soil moistures was established by polarimetric decomposition models and a generalized regression neural network (GRNN). The experiments were executed over two agricultural sites on the Tigris Basin, Turkey. The study consists of four phases. In the first stage, Radarsat-2 data were acquired on different dates and in situ measurements were implemented simultaneously. In the second phase, the Radarsat-2 data were pre-processed and the GPS coordinates of the soil sample points were imported to this data. Then the standard sigma backscattering coefficients with the Freeman–Durden and H/A/α polarimetric decomposition models were employed for feature extraction and a feature vector with four sigma backscattering coefficients (σhh, σhv, σvh, and σvv) and six polarimetric decomposition parameters (entropy, anisotropy, alpha angle, volume scattering, odd bounce, and double bounce) were generated for each pattern. In the last stage, GRNN was used to estimate the regional soil moisture with the aid of feature vectors. The results indicated that radar is a strong remote sensing tool for soil moisture estimation, with mean absolute errors around 2.31 vol %, 2.11 vol %, and 2.10 vol % for Datasets 1–3, respectively; and 2.46 vol %, 2.70 vol %, 7.09 vol %, and 5.70 vol % on Datasets 1 &amp; 2, 2 &amp; 3, 1 &amp; 3, and 1 &amp; 2 &amp; 3, respectively.

Reproductive characteristics of Siahmahi, Capoeta damascina (family: Cyprinidae) in Beheshtabad river, Tigris basin

A total of 426 specimens of Mesopotamian barb (Siahmahi) Capoeta damascina (Cyprinidae) were caught by gillnets (1–6 cm mesh sizes) from Beheshtabad River, Chaharmahal and Bakhtiari Province from May 2013 to June 2014. Fish specimens were anesthetized in 1% clove oil solution, fixed in 10% buffered formalin and transported to the laboratory for further analyses. Fork lengths of the sampled fish ranged from 8.94 cm to 42.45 (23.32±6.53SD) cm and total weight from 10.3 to 1255.5 (242.5±213.4) g. Based on scale readings, the maximum age was found to be 7+ years for males and 8+ for females. Six reproductive characteristics, viz: sex ratio, Gonadosomatic Index (GSI), Hepatosomatic Index (HSI), relative fecundity, absolute fecundity and ova diameter were determined. The smallest mature male and female were 11.2 and 18.5 cm in fork length respectively. Sex ratio was 1M:0.7F. The GSI showed that spawning occurred from March to June. Oocyte diameters ranged from 0.57 to 2.48 (1.30±0.41) mm. Absolute fecundity ranged between 2260 and 51770 (15360±12030) eggs. Absolute fecundity and fish size (fork length and total weight) were highly correlated. Relative fecundity varied from 11 to 65 (33±12) eggs per gram of total body weight. The average hepatosomatic index was 2.25 ± 0.05 and the highest value was observed in March (3.05 ± 0.31).

Length-weight relationships and condition factors of Alburnus zagrosensis Coad, 2009, from three rivers of Tigris basin in Iran (Teleostei: Cyprinidae)

The length–weight relationships and condition factors of 145 specimens for three populations of Alburnus zagrosensis Coad, 2009, an endemic species in Tigris River basin in Chaharmahal and Bakhtiari Province, Iran, were studied for the first time. The b value for Cheshmeh-Ali population was 3.19, for Hamzeh-Ali was 3.69 and for Polmari was 2.87, indicating a positive allometric growth pattern for Hamzeh-Ali and isometric growth pattern in the two other populations of A. zagrosensis . The condition factor varied from 0.74-0.93 in the populations. These information are vital in fisheries biology and could be used for species conservation and management.

The complete description of the skeletal structure of Hafez loach, Turcinoemacheilus hafezi (Cypriniformes, Nemacheilidae)

The osteological characteristics is an important tool for clarification of the phylogenetic statue of the family Nemechelidae. Since any information is available about osteological features of the genus Turcinoemacheilus , hence the present study provides a detailed osteological characteristics of the Turcinoemacheilus hafezi as representative of this genus. Ten specimens of T. hafezi were collected from the Shalamzar Stream, Tigris basin, Iran and cleared and stained for osteological examination. According to the results, T. hafezi is osteologicaly characterized by absence of the preethmoideum-I and postcleithrum, having four basibranchials, presence of the sesamoid ossification, free and short epural with the reduced neural process and pleurostyle, connection of the hypural-1 to the parahypural, no connection of the hypurals 3, 4, and 5 to the pleurostyle, and no bony bridge between the parietal.

The Rebirth of Water as a Weapon: IS in Syria and Iraq

The so-called Islamic State (IS) has increasingly used water as a weapon in order to further its political and military aims in Syria and Iraq. In this water-scarce region, IS has retained water and cut off crucial supplies, flooded large areas as well as contaminated resources. The capture of large dams in the Euphrates and Tigris basin has made it possible to deploy the water weapon even more effectively and in a frequent, systematic, consistent and flexible manner. Measures to counter this weaponisation effectively have been limited to military means. However, several internal constraints create a dilemma for IS as its state-building ambitions conflict with the consequences of the weaponisation of water. The rebirth of using the water weapon in Syria and Iraq raises questions about protecting water infrastructures in conflict and post-conflict settings.

Life history traits of Capoeta trutta (Heckel, 1843) from Seymareh River, western Iran (Teleostei: Cyprinidae)

In the present study, some biological aspects of Capoeta trutta (Heckel, 1843) have been examined for the aim of future stock assessment, exploitation and conservational managements. A total of 103 fish specimens were collected seasonally from Seymareh River, Tigris basin, Iran, in four seasons during 2011-2012. Observed maximum age was 4 + in both sexes and sex ratio obtained as 1M:1.9F. Analyses showed a highly significant length-weight relationship of 0.98 for C. trutta with a b parameter of 3.09. Generally, females were larger than males with the maximum length of 28.0cm and minimum of 9.8cm. Mean Relative Length of Gut (RLG), weight ( W ) and total length (TL) were calculated according to size classes and ages. The most frequent size belonged to 20-24cm length group with the percentages of 52.9 and 48.6 for females and males, respectively. Based on the results of main reproductive indices; Gonado-Somatic Index (GSI), Modified Gonado-Somatic Index (MGSI) and Dobriyal Index (DI), C. trutta spawns once a year in spring. Condition factor ( K ) value also revealed the peak in the spring which is in accordance with the highest gonadal maturity of this species. The mean value for RLG was obtained as 4.6 and Zihler’s index (ZI) was calculated as 2.11. Based on RLG and Zihler indices, C. trutta might be considered an herbivore species.

THE POWER STRUGGLE IN THE LAYER OF TRANSNATIONAL HYDROPOLITICS: THE CASE OF THE ILISU DAM PROJECT

The study analyses hydropolitical relations among state and non-state actors in the context of the layer of transnational hydropolitics by looking at the controversy over the construction of the Ilisu dam project. Turkey is fully engaged in its „hydraulic mission‟, very extensively and rapidly „developing‟ water resources throughout its territory. Some of these flows cross international borders, specifically very heavily contested Euphrates and Tigris basin. This large basin has attracted considerable academic attention, notably in regards to Turkey‟s relations with downstream neighbours, Syria and Iraq. Yet, the great bulk of the existing analysis falls prey to two broader weaknesses; a) it has narrowly applied the recently developed literature regarding the role of power in transboundary water politics, and b) it has neglected or under-emphasized how non-state actors enrol in hydropolitical processes. Informed by deep investigation of the case study regarding the recent controversy over the construction of the Ilisu dam on the Tigris River, the study proposes a conceptual framework that seeks to analyse how power dynamics are at work at different scales of hydropolitics other than inter-state relations between the riparian states and how both discursive and material power capabilities influence the outcome of interactions as well as conflictual and cooperative relations between the state and non-state actors. The application of the conceptual framework to the relations between opponents and proponents of the construction of the Ilisu dam project shows how power dynamics change over time and they strongly shape conflictual relations between the actors. By highlighting the influence of the transnational anti-dam activist networks, the study shows the relevance of including non-state actors into analysis. The study shows that such actors lack material power but are able to use discursive (ideational and bargaining) power very effectively to meet their interests.

Descriptive Osteology of a Newly Described Stone Loach,Oxynoemacheilus chomanicus(Kamangar et al., 2014) (Cypriniformes, Nemacheilidae)

Oxynoemacheilus chomanicusis a newly described species of the family Nemacheilidae from the Choman River drainage of the Tigris basin. This study was conducted to provide the detailed osteological characteristics of this species and comparing them with those of other endemic species of the genusOxynoemacheilusfrom inland water basins of Iran, namely,kiabii,O. persa,O. brandtii,O. kermanshahensis, andO. bergianus. For this purpose, nine specimens ofO. chomanicuswere collected, cleaned, and stained for osteological examination. Then, a detailed description of their skeletal structure was provided. The results showed thatO. chomanicuscan be distinguished from other studied species of the genusOxynoemacheilusdue to possessing an orbital shelf, number of the vertebrae, number of the hypurals, number of the unbranched rays in anal fin, features of the hemal and neural spines, and connection pattern of the parietal and frontal.