The ontogeny of the pelturine olenid trilobite Leptoplastides salteri (Callaway, 1877) from the Shineton Shales, Shropshire, England, was first described in 1925 by Frank Raw. Since that time, scanning electron microscopy and other new technologies have revealed many more details of structure, of early developmental stages in particular, than were available to Raw. Whereas protaspides are not preserved and the state of preservation is less than perfect for the smallest meraspides, we have established that the latter had an array of delicate, long thoracic and pygidial spines, as well as paired procranidial spines, which disappear by meraspid degree 8. Raw's reconstructions of early meraspides, and his measurements of the early stages in development, are here amended in the light of new information. Dorsal spines in the adult are much more highly developed than have been documented in any other olenid. The hypostome is preserved in place in several specimens. Initially conterminant (attached to the doublure), it becomes natant (free) in late meraspid to early holaspid stages of development, with its anterior contour fitting exactly to that of the glabella. The ecology of the widespread Leptoplastides is best known from very extensive sections in South America, which provide a useful basis for comparison. It was well adapted to a range of environments, both oxygenated and dysoxic, and is usually the dominant taxon in the biofacies in which it is found.

中文翻译：

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早期奥陶纪三叶虫 Leptoplastides salteri 的个体发育修正（Callaway，1877）

pelturine olenid 三叶虫的个体发育盐藻(Callaway, 1877) 来自英格兰什罗普郡的 Shineton 页岩，于 1925 年由 Frank Raw 首次描述。从那时起，扫描电子显微镜和其他新技术揭示的结构细节，特别是早期发育阶段的细节，比 Raw 所能得到的要多。鉴于前鳍没有保存并且保存状态对于最小的后鳍来说并不完美，我们已经确定后者有一系列精致的、长的胸椎和尾棘，以及成对的前颅棘，它们在 8 度时消失. Raw 对早期 mesaspides 的重建，以及他对发育早期阶段的测量，在此根据新信息进行了修正。成人的背刺比任何其他 olenid 记录的要高度发达得多。假体在几个标本中保存在适当的位置。最初是决定性的（附着在双重体上），它在发育的晚期到早期的holaspid阶段变得清晰（自由），其前部轮廓与眉间的轮廓完全吻合。广泛的生态细质体在南美洲非常广泛的部分中最为人所知，这为比较提供了有用的基础。它很好地适应了各种环境，包括含氧和缺氧环境，并且通常是发现它的生物相中的主要分类单元。