Hurdia victoria的重建結(jié)構(gòu)。由Marianne Collins于2008年所畫,。來源：《科學(xué)》
據(jù)3月20日的《科學(xué)》雜志報(bào)道說,，大約在5億4000年到5億年前，一種叫做Hurdia 的節(jié)肢動物及其近親在寒武紀(jì)的海洋中占據(jù)著統(tǒng)治的地位,，它們的體型長得要比其它生物更大,，可能還獵食了許多其它的生物。
通過分析了數(shù)百個寒武紀(jì)的化石（其中包括某些新近才從一個博物館中獲得的材料）之后，研究人員現(xiàn)在已經(jīng)拼接出了一幅較為清晰的Hurdia 的圖像以及它在其它奇蝦類系譜圖中的位置,。該種動物的相對較大的體型及其多齒的口腔使得它們獲得了一個綽號：“寒武紀(jì)的霸王龍” Hurdia 是加拿大Burgess Shale化石帶中最常見的奇蝦類動物，但其在早期節(jié)肢動物進(jìn)化中的意義的許多方面仍然不為人知,，因?yàn)槠湓S多部位的分類在橫跨至少8個屬中都是不正確的,。
新的分析澄清了Hurdia 的身體特征以及它們與其它奇蝦類動物的異同點(diǎn)。 Hurdia 的引人注目的大頭甲可能是獨(dú)特的,，它的腮部結(jié)構(gòu)為人們了解節(jié)肢動物的肢體和呼吸器官的起源提供了線索,。（生物谷Bioon.com）
生物谷推薦原始出處：
Science 20 March 2009:DOI: 10.1126/science.1169514
The Burgess Shale Anomalocaridid Hurdia and Its Significance for Early Euarthropod Evolution
Allison C. Daley,1* Graham E. Budd,1 Jean-Bernard Caron,2 Gregory D. Edgecombe,3 Desmond Collins4
As the largest predators of the Cambrian seas, the anomalocaridids had an important impact in structuring the first complex marine animal communities, but many aspects of anomalocaridid morphology, diversity, ecology, and affinity remain unclear owing to a paucity of specimens. Here we describe the anomalocaridid Hurdia, based on several hundred specimens from the Burgess Shale in Canada. Hurdia possesses a general body architecture similar to those of Anomalocaris and Laggania, including the presence of exceptionally well-preserved gills, but differs from those anomalocaridids by possessing a prominent anterior carapace structure. These features amplify and clarify the diversity of known anomalocaridid morphology and provide insight into the origins of important arthropod features, such as the head shield and respiratory exites.
1 Department of Earth Sciences, Palaeobiology, Uppsala University, Villav?gen 16, Uppsala SE-752 36, Sweden.
2 Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto M5S 2C6, Canada.
3 Department of Palaeontology, Natural History Museum, Cromwell Road, London SW7 5BD, UK.
4 437 Roncesvalles Avenue, Toronto M6R 3B9, Canada.
