Sand deserts are common biotopes on the earth's surface. Some specialized vertebrate species have colonized these ecological habitats by living buried in the sand. Among these so called psammophilic species are the Scincidae sand dune living species Scincus scincus and Eumeces schneideri. These two skinks share a relatively similar behavioral ecology by living buried in sand, almost all the time for S. scincus and at least for some part of the day for E. schneideri. The visual system of these two lizards was investigated by histological, immunohistochemical, Magnetic Resonance Imaging (MRI) and morphometric techniques. Both skink species exhibit a retina lacking fovea, composed predominantly of cones presenting two types of oil droplets (pale blue-green and colorless). Both species possess a subset of rod like-photoreceptors (about 1 rod for 30 cones) evidenced by anti-rhodopsin immunoreactivity. A ratio 1:1-1:2 between ganglion cells and photoreceptors points to a linear connection (photoreceptors/bipolar neurons/ganglion cells) in the retina and indicates that both skinks more likely possess good visual acuity, even in the peripheral retina. The MRI analysis revealed differences between the species concerning the eye structures, with a more spherical eye shape for S. scincus, as well as a more flattened lens. The relative lens diameter of both species seems to correspond to a rather photopic pattern. Beside the fact that S. scincus and E. schneideri have different lifestyles, their visual capacities seem similar, and, generally speaking, these two psammophilic species theoretically exhibit visual capacities not far away from non-fossorial species.

中文翻译：

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两只嗜肺蜥蜴（Scincus scincus＆Eumeces schneideri）视觉系统的比较研究。

沙漠是地球表面常见的生物群落。一些特殊的脊椎动物物种通过生活在沙子中而定居在这些生态栖息地中。在这些所谓的嗜粉沙性物种中，有Scincidae沙丘生物物种Scincus scincus和Eumeces schneideri。这两种石龙子被埋在沙子中共享着相对相似的行为生态学，沙丁鱼链球菌几乎一直都这样，而施奈德利肠杆菌至少在一天中的某些时候都如此。通过组织学，免疫组织化学，磁共振成像（MRI）和形态计量技术研究了这两只蜥蜴的视觉系统。两种石腊鱼种类都表现出缺乏中央凹的视网膜，主要由视锥细胞组成，视锥细胞呈现两种类型的油滴（浅蓝绿色和无色）。两种物种都具有杆状感光体的子集（约30个视锥细胞中的1个杆状体），通过抗视紫红质的免疫反应性得到证明。神经节细胞与光感受器之间的比例为1：1-1：2表示视网膜中的线性连接（光感受器/双极神经元/神经节细胞），这表明即使在周围视网膜中，两个皮结也更有可能拥有良好的视敏度。MRI分析显示，物种之间在眼睛结构方面存在差异，其中链球菌的球形更圆，晶状体更扁平。两种物种的相对透镜直径似乎对应于相当明暗的图案。除了S. scincus和E. schneideri拥有不同的生活方式外，它们的视觉能力似乎相似，并且通常来说，