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''Paraloxoceras'' is a straight shelled, orthoconic, nautiloid cephalopod, now extinct, that lived during the Early Carboniferous. Fossils have been found in Europe and central Asia; the type, ''P. konincki'', named by Flower, came from Belgium. The shell of ''Paraloxoceras'' is slightly depressed, with straight sutures. Septa are fairly close spaced. The siphuncle is located about half way between the center and the venter with segments that are broadly expanded into the chambers. As typical for the subfamily, ''Paraloxoceras'' contains organic endosiphuncular deposits penetrated by a canal system similar to that found in actinocerids but differs in the having a protoconch characteristic of the pseudorthocerids. During grow of the animal the shell expands dorsally with the distance between the dorsum and siphuncle increasing while the separation between the venter and siphuncle remains at a more or less constant. Related genera include ''Pseudactinoceras'', ''Macroloxoceras'', and ''Eusthenoceras'' ==References== * Sweet, W.C. 1964. Nautiloidea- Orthocerida in Treatise on Invertebrate Paleontology, Part K. Geologogical Society of America and Univ. of Kansas press; Teichert and Moore (eds) * Subfamily Pseudactinoceratinae -Paleobio db () * Sepkoski, J.J. Jr. 2002. A compendium of fossil marine animal genera. D.J. Jablonski & M.L. Foote (eds.). ''Bulletins of American Paleontology'' 363: 1–560. (Sepkoski's Online Genus Database (CEPHALOPODA) ) * ''see also'' List of nautiloids 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Paraloxoceras」の詳細全文を読む スポンサード リンク
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