Eravci Yalin Ebru, Gündemir Ozan, Günay Ebuderda, Vatansever Çelik Ezgi Can, Duro Sokol, Szara Tomasz, Blagojevic Milos, Sönmez Bektaş, Spataru Mihaela-Claudia
Department of Surgery, Faculty of Veterinary Medicine, Istanbul University-Cerrahpasa, Istanbul 34320, Türkiye.
Department of Anatomy, Faculty of Veterinary Medicine, Istanbul University-Cerrahpasa, Istanbul 34320, Türkiye.
Animals (Basel). 2024 Sep 13;14(18):2664. doi: 10.3390/ani14182664.
The carapace morphology of tortoises is a crucial characteristic used for species identification, with features such as shell shape, roughness, and color patterns varying among species. Understanding this morphological diversity is valuable not only for taxonomic classification but also for more specialized clinical approaches. This study investigated the morphological differences in the shells of Leopard tortoises (), African spurred tortoises (), and Greek tortoises (spur-thighed tortoises; ) raised in captivity. Using 3D scanners, the carapaces were modeled, and a 3D geometric morphometric method was employed to analyze shape variations and dimensional features, with landmarks applied automatically. Among the species studied, African spurred tortoises had the largest carapace size. Principal component analysis (PCA) identified PC1 and PC3 as critical factors in distinguishing between species based on morphological characteristics. Positive PC1 values, associated with a shorter carapace height, indicated a flatter or more compact shell shape. A higher PC3 value corresponded to a raised shape at the back of the shell, while a lower PC3 value indicated a raised shape at the front. Specifically, Leopard tortoises exhibited a higher carapace shape than the other species, while African spurred tortoises had shorter carapaces. An allometric effect was observed in the carapaces, where smaller specimens tended to be proportionately higher-domed, whereas larger shells displayed a lower height in shape. These findings highlight the significance of shape variations in tortoise shells, which emerge during adaptation and have important implications for taxonomy and clinical practice. Such differences should be carefully considered in veterinary care and species identification.
陆龟的背甲形态是用于物种鉴定的关键特征，不同物种的背甲形态在壳的形状、粗糙度和颜色图案等方面存在差异。了解这种形态多样性不仅对分类学分类有价值，而且对更专业的临床方法也有价值。本研究调查了人工饲养的豹纹陆龟（）、非洲马刺陆龟（）和希腊陆龟（ spur-thighed tortoises；）背甲的形态差异。使用3D扫描仪对背甲进行建模，并采用3D几何形态测量方法分析形状变化和尺寸特征，自动应用地标点。在所研究的物种中，非洲马刺陆龟的背甲尺寸最大。主成分分析（PCA）确定PC1和PC3是基于形态特征区分物种的关键因素。与较短的背甲高度相关的正PC1值表明壳的形状更扁平或更紧凑。较高的PC3值对应于壳后部的凸起形状，而较低的PC3值表明壳前部的凸起形状。具体而言，豹纹陆龟的背甲形状比其他物种更高，而非洲马刺陆龟的背甲较短。在背甲中观察到异速生长效应，较小的标本往往比例上更高拱，而较大的壳在形状上显示出较低的高度。这些发现突出了陆龟壳形状变化的重要性，这种变化在适应过程中出现，对分类学和临床实践具有重要意义。在兽医护理和物种鉴定中应仔细考虑这些差异。
