The lower strata of the Umachiri Formation from the Altiplano of southeast Peru have yielded a brachiopod-dominated assemblage, containing representatives of the brachiopod superfamilies Polytoechioidea, Orthoidea, and Porambonitoidea, as well as subsidiary trilobite and echinoderm remains. Two new polytoechioid genera and species,Enriquetoechia umachiriensisnew genus new species andAltiplanotoechia hodginin. gen. n. sp. Colmenar in Colmenar and Hodgin, 2020, and one new species,Pomatotrema laubacherin. sp., are described. The presence ofPomatotremain the Peruvian Altiplano represents the occurrence at highest paleolatitude of this genus, normally restricted to low-latitude successions from Laurentia and South China. Other polytoechioids belonging toTritoechia(Tritoechia) andTritoechia(Parvitritoechia) also occur. Identified species of orthoids from the generaParalenorthis,Mollesella, andPanderina? occur in the Peruvian Cordillera Oriental and in the Argentinian Famatina Range. The only porambonitoid represented is closely related toRugostrophia latireticulataNeuman, 1976 from New World Island, interpreted as peri-Laurentian. These brachiopod occurrences indicate a strong biogeographic affinity of the Peruvian Altiplano with the Famatina and western Puna regions, suggesting that the brachiopod faunas of the Peruvian Altiplano, Famatina, and western Puna belonged to a well-differentiated biogeographical subprovince during the Early–Middle Ordovician on the margin of southwestern Gondwana. Links with peri-Laurentian and other low-latitude terranes could be explained by island hopping and/or continuous island arcs, which might facilitate brachiopod larvae dispersal from the Peruvian Altiplano to those terranes across the Iapetus Ocean. Brachiopods from the lower part of the Umachiri Formation indicate a Floian–?Dapingian age, becoming the oldest Ordovician fossils of the Peruvian Altiplano.UUID:http://zoobank.org/9670a000-260d-4d75-9261-110854c7afb8

中文翻译：

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秘鲁高原下-?中奥陶统(Floian-?Dapingian)腕足动物的首次证据及其古地理意义

来自秘鲁东南部高原的 Umachiri 组的下部地层产生了以腕足类动物为主的组合，包含腕足类动物超科 Polytoechioidea、Orthoidea 和 Porambonitoidea 的代表，以及附属的三叶虫和棘皮动物遗骸。两个新的多甲壳虫属和种，Enriquetoechia umachiriensis新属新种和滇滇绦虫n. 将军 n. sp。Colmenar 和 Hodgin 中的 Colmenar，2020 年，以及一个新物种，油菜n. sp., 进行了描述。的存在旋风虫在秘鲁高原上代表该属最高古纬度的发生，通常仅限于来自劳伦蒂亚和华南的低纬度序列。其他属于栉水母(栉水母） 和栉水母(小栀子) 也会发生。从该属中识别出的正畸物种平行线,莫莱塞拉， 和潘德丽娜? 发生在秘鲁东科迪勒拉山脉和阿根廷法马蒂纳山脉。唯一代表的porambonitoid与毛茛Neuman，1976 年来自新世界岛，被解释为 peri-Laurentian。这些腕足类动物的出现表明秘鲁高原与法马蒂纳和普纳西部地区具有很强的生物地理相似性，表明秘鲁高原、法马蒂纳和普纳西部的腕足动物群属于早-中奥陶世时期分化良好的生物地理亚省。冈瓦纳西南边缘。与 peri-Laurentian 和其他低纬度地体的联系可以通过跳岛和/或连续岛弧来解释，这可能有助于腕足类动物幼虫从秘鲁高原扩散到横跨 Iapetus 海洋的那些地体。Umachiri 组下部的腕足类动物显示了弗洛亚-？大坪纪，成为秘鲁高原最古老的奥陶纪化石。UUID：http://zoobank.org/9670a000-260d-4d75-9261-110854c7afb8