Using otolith shape and morphometry to identify four Alburnus species (A. chalcoides, A. escherichii, A. mossulensis and A. tarichi) in Turkish inland waters Summary Asteriscus otolith shapes as well as their morphometry and shape contours were investigated in order to identify four allopatric Alburnus species: A. chalcoides (G€ uldenst€ adt, 1772) (Ordu), A. escherichii Steindachner, 1897 (Eskis ßehir), A. mossulensis Heckel, 1843 (Tunceli), and A. tarichi (G€ uldenst€ adt, 1814) (Van) in Turkish inland waters. These were compared using the shape indices (form factor, roundness, circularity, ellipticity, rectangularity and aspect ratio), and the morphological characters [otolith weight (OWE), otolith length (OL), otolith width (OW), otolith perimeter (OP), and otolith area (OA)]. The overall canonical discriminant analysis (CDA) classification score was 93.8%, with the lowest score for A. escherichii (82.5%) and the highest for A. chalcoides (100%). The otolith shapes, morphology and shape contours of all sampled fish were a clear species differentiator, thereby demonstrating that the otolith shape is species-specific. The current study presents for the first time comprehensive variation information on interspecific leftright asteriscus otoliths in males and females of each Alburnus species: A. chalcoides from Ordu, A. escherichii from Eskis ßehir, A. mossulensis from Tunceli and A. tarichi from Van, based on a total of 307 individuals. Scanning electron microscopy (SEM) images, shape contours and other otolith characters vary within the same genus; these differences should be investigated not only in other freshwater fish species or genera but also in the same species living in different habitats. In addition, further investigation is required not only with respect to the morphometry, biometry, shape, geometry, and shape contours of the otoliths, but also regarding the genetic methods for robust identification of various sympatric and allopatric fish populations. U.S.

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The relationships between size (length and width) of the lagenar (asteriscus) and the utricular (lapillus) otoliths and body length for five cyprinid fish species, freshwater bream Abramis brama, white bream Blicca bjoerkna, Prussian carp Carassius gibelio, brond-snout Chondrostoma regium, and rudd Scardinius erythrophthalmus, collected from Lake Ladik from November 2009 through October 2010, are presented. The right and left side measurements of otoliths were pooled in all cases except asteriscus length in Prussian carp. Nonlinear and linear functions provided the best fit for 80% and 20% of all species, respectively. All relationships were highly significant (P < 0.001, R 2 > 0.71) and the mean percent prediction errors were less than 10%. The results showed that reliable original size estimates of all species studied are obtainable from their otolith biometrics. The regressions from this study can be useful for investigators examining food habits of piscivorous fauna and sizes of these fishes in archaeological samples.

In the present study, a comparison of the otolith morphology of Alburnus tarichi, collected from different localities throughout Van Basin was carried on. A total of 351 specimens of A.tarichi collected by trammel nets from four different localities (Van, Erçek, Nazik, Aygır) during the period April-May 2015 were examined. Fork length and body weight of the specimens ranged between 9.9-24.6 cm and 8.4-176.5 g, respectively. Lagenar otoliths were removed discriminating as left and right. Otolith length (OL), otolith breadth (OB) and otolith weight (OW) were collected. Comparisons of right-left otolith measurements were tested by paired t test. Comparisons of otolith breadth, length and weight of A. tarichi among all localities were tested by ANOVA. There were no significant difference in terms of otolith length and weight between right and left otoliths but there were statistically significant difference in terms of otolith breadth between the specimens collected in Lake Van and Lake Erçek. There were no differences between right and left otolith measurements in Lake Nazik and Lake Aygır. Comparing all localities together, otolith length, breadth and weight were different from each other for four localities. The power model was applied to estimate the relationships between the otolith measurements and fish length.

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in order to determine the age, growth, and reproductive season. Fork lengths and weights of these samples varied between 11.5-24.3 cm and 22.80-259.00 g, respectively. Age estimates obtained from scales and vertebrae were compared to determine the most reliable bony structure for ageing. The precision analyses indicated that scales were the most appropriate hard structures for determining the age of white bream. Ages of all the specimens ranged from I to VI years and age group III was dominant. The parameters of the von Bertalanffy growth equations were calculated as L∞ = 32.85 cm, W∞ = 707.76 g, k = 0.11 year -1 and t0 = -2.64 year, and the growth performance index (Φ') value was computed as 2.074 for combined sexes. Fork length-weight relationship was found to be W = 0.0066 FL 3.317 . The mean condition factor was the highest in August and the lowest in October. The gonadosomatic index values showed that the reproduction occurred between May and June.Keywords: Ageing, scale, growth, reproduction season, Blicca bjoerkna, Lake Ladik Pul ve omurdan elde edilen yaşlar en güvenilir kemiksi yapının tespit edilmesi amacıyla karşılaştırılmıştır. Uyum analizleri Tahta Balığı'nın yaşının belirlenmesi için en uygun yapının pul olduğunu göstermiştir. Örneklerin yaşları I-VI arasında dağılım göstermiş ve III yaş grubu baskın yıl sınıfını oluşturmuştur. Populasyon genelinde von Bertalanffy büyüme denklemi parametreleri L∞ = 32,85 cm, W∞ = 707,76 g, k = 0,11 yıl -1 ve t0 = -2,64 yıl ve büyüme performans indeks değeri (Φ') 2,074 olarak hesaplanmıştır. Çatal boy-ağırlık ilişkisi W = 0,0066 ÇB 3,317 şeklinde elde edilmiştir. En yüksek ve en düşük ortalama kondisyon faktörü değerleri sırasıyla Ağustos ve Ekim aylarında elde edilmiştir. Gonadosomatik indeks değerleri üreme faaliyetinin Mayıs-Haziran aylarında gerçekleştiğini göstermiştir. RESEARCH ARTICLE

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doi:10.3906/zoo-1312-5