Data from: Evolution of the rudist bivalve Agriopleura Kühn (Radiolitidae, Hippuritida) from the Mediterranean region

The genus Agriopleura (Radiolitidae) is restricted to the Lower Cretaceous of the Mediterranean region, including the Middle East, and this rudist is apparently absent from the New World. Agriopleura underwent a size increase from late Hauterivian to mid-late Barremian, matching Cope's rule, followed by a Lilliput phase in the early Aptian. The relative development of radial bands increased through time and represents a key evolutionary index. During its evolution, Agriopleura increased in species diversity and expanded geographically onto the European Mediterranean Tethyan margin from the late Hauterivian to Barremian, after which it disappeared from the region (pseudotermination). In the lower Aptian, after a Lazarus gap, the genus reappears in the southern Mediterranean Tethyan margin. Assuming that Archaeoradiolites is the direct descendant of Agriopleura, the disappearance of the genus in the mid-Aptian was a pseudoextinction and this coincided with a major crisis of shallow carbonate settings and their associated biota. The definition of Agriopleura species is based on a set of qualitative and quantitative external and internal characters. Five species are recognized: three Barremian species, Agriopleura blumenbachi, the type species, A. marticensis and A. carinata; one lower Aptian species A. libanica; and a new species A. sequana restricted to the upper Hauterivian. Principal component analysis is used to test the distinctiveness of the species and the pattern of relationships of some of their key quantitative characters.

阿格利奥蛤属（Agriopleura，放射壳蛤科Radiolitidae）的分布仅局限于地中海区域（含中东）的下白垩统，该固着蛤类在新大陆中无分布记录。该属自豪特里维阶晚期至巴列姆阶中晚期呈现体型持续增大的演化趋势，符合科普法则（Cope's rule），随后在阿普第阶早期进入侏儒演化阶段。放射带的相对发育程度随地质时间不断提升，成为该类群的关键演化指标。在演化历程中，阿格利奥蛤属的物种多样性逐步提升，并于豪特里维阶晚期至巴列姆阶期间，地理分布扩张至欧洲地中海特提斯陆缘，此后便从该区域消失（假终止）。在阿普第阶早期，经历拉撒路间隔后，该属再度现身于地中海南部特提斯陆缘。若假定古放射蛤属（Archaeoradiolites）是阿格利奥蛤属的直接后裔，则阿格利奥蛤属在阿普第阶中期的消失实为假灭绝事件，这一事件与浅海碳酸盐岩沉积环境及其伴生生物群的重大危机恰好重合。阿格利奥蛤属物种的界定基于一系列定性与定量的内外形态特征。目前共识别出5个有效物种：3个巴列姆阶物种，即模式种布氏阿格利奥蛤（Agriopleura blumenbachi）、A. marticensis与A. carinata；1个阿普第阶早期物种A. libanica；以及仅分布于豪特里维阶上部的新种A. sequana。本研究采用主成分分析（Principal Component Analysis, PCA）检验各物种的区分度，以及部分关键定量特征的关联模式。