Abstract: Not Available
Arvicola terrestris (Lin, 1758) is distributed in Europe, Russia, Turkey, Iran and Palestine (Ellerman and Morrison-Scott, 1951; Corbet, 1978; Harrison and Bates, 1991). Also, Steiner and Vauk (1966) noted A. terrestris from Beyşehir lake. Mursalolu (1975) collected specimens from various localities in Turkey. These studies are based on distribution along with morphological aspects of this species. Karyology of A. terrestris in Asia Minor was analysed by Ozkurt et al. (1999). The aim of the present study is to examine karyological characteristics of A. terrestris in Turkish Thrace.
Eight specimens from Kırklareli in Turkish Thrace were karyotyped from the bone marrow of the colchicined animal (Ford and Hamerton, 1956).
The diploid number of chromosomes is 2n = 36, the number of autosomal arms is NFa = 60 and the fundamental number is NF = 64. The autosomal set has 7 pairs of metacentrics, 6 pairs of submetacentrics and 4 pairs of acrocentrics. The X chromosome is large submetacentric and the Y chromosome is medium-sized acrocentric (Fig. 1).
Kuliev et al. (1978) reported NF = 72 for A. terrestris from Novosibirsk and NF = 66 for Azerbaijan population. These values are different from NF and NFa values of population from Turkish Thrace.
| Fig. 1: | Karyotype of male Arvicola terrestris from Kırklareli |
According to Zima and Kral (1984), European populations have 2n = 36 chromosomes, NFa = 60-68, 13 pairs of meta-submetacentrics and 4 pairs of subtelo-acrocentrics and the X choromosome is submetacentric and the Y chromosome is acrocentric. These karyotypic values given by Zima and Kral (1984) are consistent with our findings. Four acrocentric pairs were observed by Raicu et al. (1971) in population from Romania and by Kuliev et al. (1978) in one locality from Caucasia as in this study. Özkurt et al. (1999) found medium sized-submetacentric Y chromosome, 18 metacentric and 8 subtelocentric in the karyotype of population in Kırşehir (Asia Minor). These values are different from those of population in Turkish Thrace. These findings show that there are variations in karyotype of A. terrestris. Also, the karyotype of A. terrestris population in Turkish Thrace is similar to both that of European and that of Caucasian population and differ from Asia Minor, Novosibirsk and Azerbaijan population with respect to some karyotypic characteristics.