Schwarzhans Werner, Mörs Thomas, Engelbrecht Andrea, Reguero Marcelo, Kriwet Jürgen
Ahrensburger Weg 103, D-22359 Hamburg, Germany; Natural History Museum of Denmark, Zoological Museum, Universitetsparken 15, DK-2100 Copenhagen, Denmark.
Swedish Museum of Natural History, Department of Palaeobiology, P.O. Box 5007, SE-10405 Stockholm, Sweden.
J Syst Palaeontol. 2017;15(2):147-170. doi: 10.1080/14772019.2016.1151958. Epub 2016 Mar 16.
The first record of fossil teleostean otoliths from Antarctica is reported. The fossils were obtained from late Early Eocene shell beds of the La Meseta Formation, Seymour Island that represent the last temperate marine climate phase in Antarctica prior to the onset of cooling and subsequent glaciation during the late Eocene. A total of 17 otolith-based teleost taxa are recognized, with 10 being identifiable to species level containing nine new species and one new genus: sp. nov., sp. nov., sp. nov., sp. nov., sp. nov., sp. nov., sp. nov., gen. et sp. nov. and sp. nov. sp. nov. is also known from the late Eocene of Southern Australia, and Schwarzhans, widespread in the southern oceans during the Eocene, has been recorded from New Zealand, southern Australia, and now Antarctica. The otolith assemblage shows a typical composition of temperate fishes dominated by gadiforms, very similar at genus and family levels to associations known from middle Eocene strata of New Zealand and the late Eocene of southern Australia, but also to the temperate Northern Hemisphere associations from the Paleocene of Denmark. The Seymour Island fauna bridges a gap in the record of global temperate marine teleost faunas during the early Eocene climate maximum. The dominant gadiforms are interpreted as the main temperate faunal component, as in the Paleocene of Denmark. Here they are represented by the families Moridae, Merlucciidae (Macruroninae), Macrouridae and Gadidae. Nowadays Gadidae are a chiefly Northern Hemisphere temperate family. Moridae, Macruroninae and Macrouridae live today on the lower shelf to deep-water or mesopelagically with Macruroninae being restricted to the Southern Ocean. The extant endemic Antarctic gadiform family Muraenolepididae is missing, as are the dominant modern Antarctic fishes of the perciform suborder Notothenioidei. Recently, there has been much debate on isolated jaw bones of teleost fishes found in the La Meseta Formation and whether they would represent gadiforms (Merlucciidae in this case) or some early, primitive notothenioid. Otoliths are known to often complement rather than duplicate skeletal finds. With this in mind, we conclude that our otolith data support the presence of gadiforms in the early Eocene of Antarctica while it does not rule out the presence of notothenioids at the same time. http://zoobank.org/urn:lsid:zoobank.org:pub:A30E5364-0003-4467-B902-43A41AD456CC.
本文报道了南极洲硬骨鱼耳石的首次化石记录。这些化石采自西摩岛拉梅塞塔组始新世早期晚期的贝壳层，该贝壳层代表了南极洲在始新世晚期变冷及随后冰川作用开始之前的最后一个温带海洋气候阶段。共识别出17个基于耳石的硬骨鱼分类单元，其中10个可鉴定到物种水平，包括9个新物种和1个新属：[具体物种1]新种、[具体物种2]新种、[具体物种3]新种、[具体物种4]新种、[具体物种5]新种、[具体物种6]新种、[具体物种7]新种、[新属及具体物种]新属新种、[具体物种8]新种、[具体物种9]新种。[具体物种1]新种在澳大利亚南部始新世晚期也有发现，而在始新世广泛分布于南大洋的[某种鱼类名称]施瓦茨汉斯鱼，已在新西兰、澳大利亚南部以及现在的南极洲被记录到。耳石组合显示出以鳕形目鱼类为主的典型温带鱼类组成，在属和科的层面上，与新西兰始新世中期地层以及澳大利亚南部始新世晚期已知的组合非常相似，同时也与丹麦古新世的北半球温带组合相似。西摩岛动物群填补了始新世气候最暖期全球温带海洋硬骨鱼动物群记录中的一个空白。占主导地位的鳕形目鱼类被解释为主要的温带动物群组成部分，如同在丹麦古新世一样。在这里，它们由稚鳕科、无须鳕科（长尾鳕亚科）、鼠尾鳕科和鳕科代表。如今鳕科主要是北半球温带的一个科。稚鳕科、长尾鳕亚科和鼠尾鳕科现今生活在陆架下层至深水区域或中层水域，长尾鳕亚科仅限于南大洋。现存的南极特有鳕形目鱼类南极长吻鱼科缺失，鲈形目南极鱼亚目的主要现代南极鱼类也缺失。最近，对于在拉梅塞塔组发现的硬骨鱼孤立颌骨以及它们是否代表鳕形目鱼类（在这种情况下是无须鳕科）或一些早期、原始南极鱼亚目鱼类存在很多争论。耳石通常被认为是对骨骼发现的补充而非重复。考虑到这一点，我们得出结论，我们的耳石数据支持南极洲始新世早期存在鳕形目鱼类，同时并不排除南极鱼亚目鱼类也存在的可能性。http://zoobank.org/urn:lsid:zoobank.org:pub:A30E5364-0003-4467-B902-43A41AD456CC 。
