The highly fossiliferous St. Marys Formation is exposed along Calvert Cliffs, Maryland, and comprises one of the best available records of late Miocene life in the northeastern United States. Rachycentron stremphaencus new species, a cobia from the late Miocene (Tortonian) of the St. Marys Formation is described herein on the basis of a single three-dimensional neurocranium. This fossil represents the earliest known occurrence of neurocranial remains of the genus Rachycentron in the record. Rachycentron stremphaencus differs from Rachycentron canadum (Linnaeus, 1766) in many ways. The most obvious include a different ornamentation of the outer surface of the cranial bones; a notably pronounced lateral ridge resulting in a considerable gradient from the dorsal-medial exposure of the frontal to its lateralmost supraorbital margin; the size, shape, and position of the sphenotic that is located in the posterior half of the neurocranium and its lateralmost edge being adjacent to the anteriormost extent of the wedge-shaped trough in the dorsal surface of the skull formed by the lateral and medial ridges; the two contralateral medial ridges forming a proportionately much wider trough on either side of the supraoccipital; the epioccipitals not reaching the rear edge of the neurocranium; and the lack of a conspicuous posterolateral prong of the intercalar.UUID: http://zoobank.org/c8523bb4-2de2-4318-9a37-027f463a0441

中文翻译：

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来自美国马里兰州卡尔弗特悬崖的中新世圣玛丽组的一种新军曹鱼（Teleostei，Rachycentridae）物种

高度含化石的 St. Marys 组暴露在马里兰州 Calvert Cliffs 沿线，是美国东北部中新世晚期生命的最佳可用记录之一。链球菌新物种，来自圣玛丽组的晚中新世（Tortonian）的军曹鱼在本文中基于单个三维神经颅进行描述。这块化石代表了已知最早出现的该属的颅脑残骸锐速中心在记录中。链球菌不同于Rachycentron canadum（林奈，1766）在许多方面。最明显的包括颅骨外表面的不同装饰；一个显着的侧脊，导致从正面的背内侧暴露到其最外侧的眶上缘有相当大的梯度；位于颅神经后半部的蝶骨的大小、形状和位置，其最外侧边缘与颅骨背侧由外侧脊和内侧脊形成的楔形槽的最前范围相邻; 两个对侧内侧脊在枕上两侧形成一个比例更宽的槽；枕骨没有到达神经颅后缘；并且没有明显的 intercalar.UUID 后外侧叉：http://zoobank.org/c8523bb4-2de2-4318-9a37-027f463a0441