Data from: The diverse fossil chelonians from Milia (Late Pliocene, Grevena, Greece) with a new species of Testudo Linnaeus, 1758 (Testudines: Testudinidae)

The late Pliocene (early Villafranchian, MN 16a) locality of Milia (Grevena, Greece) has yielded numerous remains of mammals, such as zygodons, mastodons, rhinocerotids, hipparions, bovids, cervids, suids, carnivorans and tapirs. Several specimens of chelonians have also been discovered and comprise a small testudinid, a geoemydid and a giant tortoise. The presence of a giant tortoise and the presence of a geoemydid with large dimensions are further examples of the trend towards gigantism evidenced by the diverse fauna of Milia. In terms of taxonomic abundance of extinct turtles, this is the richest locality in Greece. The small testudinid is of particular importance because it preserves a posteriorly flared carapace, as in the extant Testudo marginata, but the posterior carapace is much taller and anteroposteriorly shorter. These characters allow us to erect a new species, Testudo brevitesta sp. nov., and to discuss the presence of the marginated tortoise and closely related forms in Greece. The new taxon is analysed in a phylogenetic context within other extant and extinct testudinids, providing new information on the clade Testudona.希腊格雷韦纳地区的米利亚（Milia）化石点形成于上新世晚期（late Pliocene）维拉弗朗阶早期（early Villafranchian）MN 16a带，该地点产出了大量哺乳动物化石遗存，包括轭齿象、乳齿象、犀科动物、三趾马、牛科动物、鹿科动物、猪科动物、食肉目动物以及貘。此外还出土了多件龟鳖类（chelonians）化石标本，分别隶属于1种小型陆龟科类群（testudinid）、1种地龟科类群（geoemydid）以及1种巨型陆龟。巨型陆龟的出现以及大型地龟科类群的存在，进一步印证了米利亚化石点多样动物群所体现的体型巨型化演化趋势。就已灭绝龟类的分类学丰富度而言，该化石点是希腊境内化石产出最为丰富的地点。这件小型陆龟科类群标本具有特殊研究价值：其保存有向后扩展的背甲，形态与现生缘翘陆龟（Testudo marginata）相似，但背甲后部更高，且前后径更短。这些形态特征支持我们建立新种——短壳陆龟（Testudo brevitesta sp. nov.），并探讨缘翘陆龟及其近缘类群在希腊的分布情况。本研究将该新分类单元置于现生与已灭绝陆龟科类群的系统发育框架中进行分析，为龟鳖演化支（Testudona）的相关研究提供了新的科学认知。