荒漠沙蜥食物的两性差异  

Sexual Variation of Phrynocephalus przewalskii (Lacertilia:Agamidae)

作　　者：施丽敏[1] 赵伟[1] 李佳琦[1] 王莹[1] 丁未[1] 房峰杰[1] 刘迺发[1] 

机构地区：[1]兰州大学生命科学学院,兰州730000

出　　处：《四川动物》2013年第1期68-72,共5页Sichuan Journal of Zoology

摘　　要：对2008年4～6月在甘肃省甘塘、阿拉善左旗、民勤、山丹采集的荒漠沙蜥样本进行了食物两性差异的研究。主要采用剖胃法对219个荒漠沙蜥胃样的6021个食物做了识别和鉴定。结果表明,荒漠沙蜥的食性为动物性,食物多为昆虫,主要取食半翅目和膜翅目昆虫,尤其是长蝽科和蚁科(合计高于70%),取食猎物的体积大小集中在0.01～20mm3。4个种群的沙蜥对长蝽科昆虫均表现为正向选择,部分种群对蚁科昆虫表现负向选择。可能是因为沙蜥有食物选择性,对长蝽科昆虫取食较多,对拟步甲科摄食较少。较多地取食蚂蚁则是因为生境中喜好食物较少,而蚁科昆虫数量多,遇见率也较高。荒漠沙蜥雌雄个体食物生态位重叠度极高,但是卡方检验的结果却表明两性在食物组成和食物大小存在显著差异。由于雌雄个体对同种食物有相同的选择性,因此导致两性在食物组成和食物大小上存在显著差异的原因可能是雄性家域范围更大,对食物有更多选择。Sexual variation of diet was studied with the preserved specimens in Gantang, Alax Zuoqi, Minqin, Shandan from April to June, 2008. Prey observations from stomach dissection were applied. 219 stomach contents with a total of 6021 prey items were handled and measured. Our result indicated diet preference to insects is a characteristic of Phrynocephalus przewalskii, and the species mainly preyed on Hymenoptera and Hemiptera, especially Lygaeidae and Formicidae （ 〉 70% ） with the size of 0.01 -20 mm3. The four species of desert lizards tended to prey on Lygaeidae positively, mean-while, part of the population showed negative selection toward formicidae. Maybe the lizard prefer certain food rather than others, for instance, it tended to eat large numbers of Lygaeidae, with Tenebrionidae taken in lesser numbers. P. przewalskii preyed on more ants as a result of less preferred food in the habitat, and it was easy to meet ants. The niche overlap of the male and female was extremely high, but the chi-square test results suggested the male and female with significant differences in food composition and food size. Males and females showed the same food preference, and therefore the male and female presented significant difference toward food because that male is with larger home range and more choice.

关 键 词：荒漠沙蜥 食物 两性差异 

分 类 号：Q959.6[生物学—动物学] Q958.1