| 释义 |
rhipidistian, n. and a.|rɪpɪˈdɪstɪən|
[f. mod.L. Rhipidistia (E. D. Cope 1887, in Amer. Naturalist XXI. 1017), f. Gr. ῥιπίς, ῥιπίδ- fan + ἱστία pl. of ἱστίον sail + -an.]
A. n. A fossil fish belonging to the superorder Rhipidistia, which includes primitive crossopterygian fishes with paired fins that may have muscular lobes.
B. adj. Of or pertaining to a fish of this kind or the group as a whole.
1916Mem. & Proc. Manch. Lit. & Philos. Soc. LX. ii. 23 Extensive fusions may have taken place between the bones of the head of Rhipidistians. 1931J. R. Norman Hist. Fishes xvii. 358 One of the earliest members of the order is the interesting Dipterus, found in the Old Red Sandstone of Scotland along with the early Rhipidistians and Palaeoniscids. 1964Bull. Mus. Compar. Zool. Harvard CXXXI. 313 (heading) The comparative anatomy of the snout in rhipidistian fishes. Ibid. 331 The etmoid endocranium has been described in the following rhipidistian genera: Ectosteorhachis.., Eusthenopteron [etc.]. 1978Sci. Amer. Sept. 111/1 The earliest amphibians arose from a primitive group of lobe fins (the rhipidistians), and so all four-footed vertebrates (tetrapods) and their descendants also evolved from this vanished fish stock. 1979Nature 18 Jan. 176/2 The mutual relations of salmon (an actinopterygian), lungfish (a dipnoan) and cow (a mammal, a class which can be traced back to rhipidistian crossopterygians by way of reptiles and amphibians) are certainly worthy of serious consideration. |