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Author: Göran Nilson

Abstract

Studies of reproductive organs, fat body and liver in relation to different activity periods were made to describe the breeding biology of the female adder, Vipera berus, in SW Sweden. The female adder is a biennial breeder. Vitellogenesis and formation of preovulatory follicles start in autumn the non-reproductive year and continue to the end of May the following spring when ovulation takes place. Copulation precedes ovulation and sperm is found in uterus a month before ovulation. Primary oocytes were seen after ovulation in the reproductive year. Atresia were seen more frequently during reproductive years and in all classes of follicles. Clutch size (X=8.8) had a linear increase with female body size and juveniles were born in early August. Thecal gland cells increased in number and the epithelium of the uterus became hypertrophied late in the non-reproductive year and early in the reproductive year. The weight of the ovary, fat body and liver went through a cyclic pattern with the highest peak in the reproductive spring. Fat body and liver weights were lowest at the end of the gestation period. Feeding periods, fat mobilization, reproductive effort, endocrine ectivity and adaptive value of the biennial reproduction are discussed. The adaptation to short season habitats is stressed.

In: Amphibia-Reptilia

In this paper available material of the Elaphe longissima species group from Iran, presented in museum collections or collected by the authors, has been studied. Statistical cluster analyses are applied to this material. Three different taxa (hohenackeri, persica, longissima ssp.) are recognized within this group from Iran. Of three specimens of Elaphe hohenackeri, collected in Iran, two have the "taurica" form of pattern. A comparison with E.hohenackeri from different parts of its range showed that this species is monotypic.

The phenetical distance between E.l.persica and non-Iranian E.l.longissma was of similar magnitude as between these two and E.hohenackeri, which motivates a specific rank for persica. Elaphe persica n.comb. is distributed in the Alburz mountains in northern Iran. A morphological description is given on the variable juvenile morph.

A recently discovered population of Elaphe longissima in western Iran (Azarbaijan) indicates the occurence of a new diverging morph which differs from E.l.longissima in size, number of ventrals in males, subcaudals in both sexes as well as in some colour pattern.

In: Amphibia-Reptilia

Abstract

This paper describes the density fluctuations of the adder Vipera berus and its prey during seven years. The reproduction during high adder density and low food availability was compared with that seven years later in the same population during low adder density and high food availability. Female length was similar but weight status (mass/length 2.56) was significantly higher during high prey density. Female mass loss when giving birth and clutch mass were significantly higher during high availability of food, but relative clutch mass and relative mass loss were similar in the two situations. However, the variance in relative clutch mass was significantly lower with high prey density. Clutch size and mass per young were significantly higher during high prey density. During high food availability there were significant positive correlations between female length (~ age) and birth mass loss, female length and clutch mass, female length and clutch size, clutch mass and mass per young and between relative clutch mass and mass per young. During low food availability there were significant positive correlations between clutch mass and clutch size and relative clutch mass and clutch size. A significant negative correlation was found between female length and relative mass loss. This study do not conform entirely to general theories on reproductive adaptations to varying food availability (r-K strategies). During high prey density both more and heavier young were produced than during scarcity of food. A high correlation of reproductive parameters during high food availability indicates a maximal utilization of reproductive capacity in most females, while the lack of such correlations during low food availability indicates a varying access to food and fat storage possibility among females.

In: Amphibia-Reptilia

Abstract

The Anatolian "Diagonal" divides Turkish Anatolia into two major zoo- and phytogeographical regions. Along this "Diagonal" a series of closely related species of vipers are distributed: Vipera bornmuelleri, Vipera bulgardaghica, and Vipera wagneri. To this series a new species, Vipera albazona sp. n. is added. The importance of this "Diagonal" as a mechanism for dispersal and speciation is also discussed.

In: Amphibia-Reptilia