“吸血鬼魚”身長0.6英寸(約合17毫米)
“吸血鬼魚”的獠牙
這條魚是過去幾十年來發(fā)現(xiàn)的最非比尋常的脊椎動物之一
英國動物學(xué)家3月11日表示,，他們在緬甸北部河流中發(fā)現(xiàn)了一條長著“吸血鬼一般牙齒”的小魚,。
這條學(xué)名為“Danionella dracula”(達尼埃拉·德拉庫拉,，西方傳說中吸血鬼的名字)的小魚身長0.6英寸(約合17毫米),，屬于鯉形目(Cypriniform)家族,，這個家族的成員長得都像鯉魚,。據(jù)悉,，“吸血鬼魚”是在2007年4月發(fā)現(xiàn)的,，但直到現(xiàn)在才被正式命名為一個新魚種,。英國倫敦自然歷史博物館動物學(xué)家拉爾夫·布里茨(Ralf Britz)博士稱這條通體透明的小魚“非比尋常”,。
布里茨說：“這條魚是過去幾十年來發(fā)現(xiàn)的最非比尋常的脊椎動物之一。Danionella dracula長有牙齒確實讓我們大吃一驚,，因為在鯉形目家族的其它3700個種類中,，頜部都沒有長牙齒。事實上,，它們在大約5000萬年前始新世早期便失去了牙齒,。然而，Danionella dracula卻進化出自己的像吸血鬼一樣的牙齒結(jié)構(gòu),，它們的牙齒是從頜骨長出來的,，不是不斷進化的頜牙。”
倫敦自然歷史博物館宣稱,，盡管這條魚體型小的令人驚異,，但Danionella dracula并不是世界上最小的魚——這一頭銜屬于只有0.3英寸(約合7.6毫米)長的Paedocypris progenetica，這種魚同樣屬于鯉形目家屬,。這項發(fā)現(xiàn)刊登在最新一期國際生物研究期刊英國《皇家學(xué)會學(xué)報B》（Proceedings of the Royal Society B）上,。（生物谷Bioon.com）
生物谷推薦原始出處：
Spectacular morphological novelty in a miniature cyprinid fish, Danionella dracula n. sp.
Ralf Britz1,*, Kevin W Conway2 and Lukas Rüber1
1Department of Zoology, The Natural History Museum Cromwell Road, London SW7 5BD, UK
2Department of Biology, Saint Louis University 3507 Laclede Avenue, St Louis, MO 63103-2010, USA
Abstract
Danionella dracula is a new species of sexually dimorphic, miniature and highly developmentally truncated cyprinid fish. Compared with its close relative, the zebrafish Danio rerio, it lacks 44 bones or parts thereof and represents one of the most developmentally truncated vertebrates. Absence of the majority of bones appears to be due to developmental truncation via terminal deletion. In contrast to these larval-like features, D. dracula also shows several hyperossifications. Uniquely, among carp-like fishes, male D. dracula have a series of long, pointed odontoid processes on the jaws greatly resembling the jaw dentition of teleosts with true teeth. The anterior-most process in each jaw is extended as a canine-like fang projecting through the epithelium. True jaw teeth are absent from all 3700 species of cypriniforms and were lost at least in the Upper Eocene. It remains to be investigated, however, whether the conserved pathways to regulate tooth development in cypriniforms have been used in D. dracula to form and pattern the odontoid processes. This new species represents a remarkable example linking progenetic paedomorphosis via heterochronic change in developmental timing to the evolution of morphological novelties.
