A new genus and species of mixopterid eurypterid (sea scorpion) has been identified from several fossil specimens found in the Xiushan Formation, China.
Life reconstruction ofTerropterus xiushanensis. Image credit: Dinghua Yang.
Terropterus xiushanensislived approximately 435 million years ago during the Llandovery epoch of the Silurian period.
The ancient marine creature belongs to a family of sea scorpions calledMixopteridae.
“Eurypterids, or sea scorpions, are an important group of mid-Paleozoic chelicerate arthropods whose evolution and paleoecological significance have attracted much attention in recent years,” saidProfessor Bo Wangfrom the Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment at the Chinese Academy of Sciences and colleagues.
“One of the most remarkable eurypterid families is Mixopteridae, whose members are quite large and superficially scorpion-like eurypterids bearing highly specialized anterior appendages.”
“Their second, and especially the third, pair of prosomal limbs are enlarged and very spiny. These limbs were presumably used for prey-capture, and analogies can be drawn with the ‘catching basket’ formed by the spiny pedipalps of whip spiders among the arachnids.”
“Our knowledge of these bizarre animals is limited to only four species in two genera described 80 years ago:Mixopterus kiaerifrom Norway,Mixopterus multispinosusfrom New York,Mixopterus simonsonifrom Estonia, andLanarkopterus dolichoschelusfrom Scotland.”
“All are Silurian in age and come exclusively from the ancient continent of Laurussia, which constrains our knowledge of the morphological diversity, geographical distribution and evolutionary history of the group.”
Terropterus xiushanensisrepresents the first mixopterid from the ancient supercontinent of Gondwana as well as the oldest known mixopterid.
Specimens and reconstruction drawing ofTerropterus xiushanensis: (a) appendages II-VI, holotype; (b) reconstruction drawing ofTerropterus xiushanensis, dorsal and ventral views; (c) close-up of appendage V; (d) joint 5 or 6 of appendage III, paratype; (e) joint 5 or 6 of appendage III, paratype; (f) coxae, paratype; (g) genital operculum and the genital appendage, paratype. Scale bars – 5 mm in (a), (d), (f), and (g); 2 mm in (e); 1 mm in (c). Image credit: Wanget al., doi: 10.1016/j.scib.2021.07.019.
The species was relatively large, reaching up to 1 m (3.3 feet) in length, and had a ‘particularly enlarged prosomal limb III, characterized by a unique arrangement of spines.’
It likely played an important role of top predators in the Silurian marine ecosystem when there were no large vertebrate competitors.
“The paleogeographical distribution of mixopterids was rather limited until now and no examples of this group have been previously discovered in Gondwana,” the paleontologists said.
“Our first Gondwanan mixopterid — along with other eurypterids from China and some undescribed specimens — suggests an under-collecting bias in this group.”
“Future work, especially in Asia, may reveal a more cosmopolitan distribution of mixopterids and perhaps other groups of eurypterids.”
Thestudywas published in the journalScience Bulletin.
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Han Wanget al. 2021. First mixopterid eurypterids (Arthropoda: Chelicerata) from the Lower Silurian of South China.Science Bulletin66 (22): 2277-2280; doi: 10.1016/j.scib.2021.07.019

壮哉我泱泱中华

秀山恐鲎

中国寒武志留狠货真多

看着像个吃垃圾的

底栖食腐吗？

好像虱子

混足鲎一类的？

除了图片，剩下的我只认识A~Z与阿拉伯数字，欧耶✌🏻✌🏻✌🏻✌🏻✌🏻✌🏻✌🏻✌🏻✌🏻✌🏻✌🏻

不错，颜值战力很高一族