Data from: New records of the late Pliensbachian to early Toarcian (Early Jurassic) gladius-bearing coleoid cephalopods from the Ya Ha Tinda Lagerstätte, Canada

The Ya Ha Tinda Lagerstätte from Alberta, Canada, is the first Jurassic marine Konservat-Lagerstätte from North America and hosts a substantial collection of exceptionally preserved fossil Vampyropoda specimens. Vampyropods are soft-bodied cephalopods (coleoids) characterized by eight arms and an internalized chitinous shell (gladius). Due to their lack of hard parts, Vampyropoda have a fragmentary fossil record, largely limited to exceptional Lagerstätten deposits. Excavations at Ya Ha Tinda have uncovered sixteen vampyropod fossils from Pliensbachian and Toarcian strata, making it the largest deposit of Vampyropoda found outside of the Tethys Ocean (Europe and the Middle East) for the Jurassic. Here, we present a taxonomic analysis of the Ya Ha Tinda Vampyropoda specimens and the first comprehensive study of Early Jurassic vampyropods from North America.
In total, fourteen specimens have sufficient morphological details preserved on the gladius for taxonomic descriptions. Two specimens are identifiable only to the suborder Loligosepiina (one to the family Geopeltidae), while the remaining twelve specimens are identified to the genus level; six Paraplesioteuthis, three Loligosepia, one Geopeltis, one Parabelopeltis, and one Jeletzkyteuthis. The discovery of Loligosepia cf. aalensis within Pliensbachian strata pushes back the earliest occurrence of this taxon from the early Toarcian to the late Pliensbachian. With the exception of Paraplesioteuthis, this is the first time these genera have been found outside of Europe for the Jurassic; therefore, this study significantly expands their palaeogeographic range. Furthermore, with established high-resolution bio and chemostratigraphy, specimens can be assigned to ammonite zones and placed in context of the global Toarcian Oceanic Anoxic Event.

加拿大阿尔伯塔省的Ya Ha Tinda特异埋藏化石库（Lagerstätte）是北美首个侏罗纪保藏型特异埋藏化石库（Konservat-Lagerstätte），产出了大量保存极为完好的吸血鬼蛸类（Vampyropoda）化石标本。吸血鬼蛸类属于具有八只腕、体内几丁质外壳（枪盾，gladius）的软体头足类（鞘亚纲，coleoids）。由于缺乏硬质骨骼结构，吸血鬼蛸类的化石记录极为零散，几乎仅能在特异埋藏化石库中被发现。Ya Ha Tinda的发掘工作从普林斯巴阶（Pliensbachian）与托阿尔阶（Toarcian）地层中出土了16件吸血鬼蛸类化石，使其成为侏罗纪时期特提斯洋（欧洲与中东）之外已知规模最大的吸血鬼蛸类化石产出点。本研究对Ya Ha Tinda产出的吸血鬼蛸类标本开展了分类学分析，同时也是北美地区首个针对早侏罗世吸血鬼蛸类的综合性研究。
总计有14件标本的枪盾（gladius）保存了足够的形态学细节，可用于分类学描述。其中2件标本仅能鉴定至微鳍乌贼亚目（Loligosepiina）层级（1件可鉴定至古皮乌贼科（Geopeltidae）），剩余12件标本可鉴定至属级：包括6件副新箭石属（Paraplesioteuthis）、3件微鳍乌贼属（Loligosepia）、1件古皮乌贼属（Geopeltis）、1件副盾形乌贼属（Parabelopeltis）以及1件耶列茨基乌贼属（Jeletzkyteuthis）。在普林斯巴阶地层中发现的微鳍乌贼属未定种（Loligosepia cf. aalensis）将该类群的最早出现时间从早托阿尔阶提前至晚普林斯巴阶。除副新箭石属外，本次发现的这些属均为侏罗纪时期欧洲之外的首次记录，因此本研究极大拓展了它们的古地理分布范围。此外，依托已建立的高分辨率生物地层与化学地层数据，这些标本可被划分至对应的菊石带，并能置于全球托阿尔阶海洋缺氧事件的研究背景下进行分析。