{"product_id":"peronoceras-fibulatum-ammonite-fossil-with-box-and-stand-whitby-north-yorkshire-jurassic-coast-yorkshire-fossils-copy","title":"Peronoceras fibulatum Ammonite fossil with box and stand - Whitby, North Yorkshire Jurassic Coast Yorkshire Fossils","description":"\u003cp\u003eAmmonite fossil found near Whitby, North Yorkshire on the Jurassic coast\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cmeta charset=\"UTF-8\"\u003e\n\u003cp class=\"p1\"\u003e\u003cspan class=\"s1\"\u003eFibulation (looped ribs) combined with spines is usually a particular feature of most Peronoceras species; although fibulation is usually absent in P.perarmatum. In Yorkshire there are the more compressed (slender) finer-ribbed P. turriculatum and P. fibulatum (the former having less looped ribs on inner whorls), and then the depressed (thicker) coarser-ribbed P. subarmatum and P.permaratum (the latter usually possessing no looped ribs). To add to the confusion there are also many intermediary forms.\u003cspan class=\"Apple-converted-space\"\u003e \u003c\/span\u003eOn all these species the ribs bend forward over the top, but more notably on the 2 former more slender species.\u003cspan class=\"Apple-converted-space\"\u003e \u003c\/span\u003eSpines are usually much more robust on the thicker 2 latter species.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"p2\"\u003eActual ammonite size: 5.3cm\u003c\/p\u003e\n\u003cp class=\"p1\"\u003e\u003cspan class=\"s1\"\u003eAge (lithology): Upper Lias; Toarcian; Bifrons zone; Fibulatum subzone.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"p2\"\u003e \u003c\/p\u003e\n\u003cp class=\"p1\"\u003e\u003cspan class=\"s1\"\u003eDistribution: Staithes, Port Mulgrave, Runswick, Kettleness, Sandsend, Hawsker, Ravenscar.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"p2\"\u003e \u003c\/p\u003e\n\u003cp class=\"p1\"\u003e\u003cspan class=\"s1\"\u003eOccurrence: Common (but much less so P.permaratum)\u003c\/span\u003e\u003c\/p\u003e","brand":"Yorkshire.Fossils","offers":[{"title":"Default Title","offer_id":67678722916388,"sku":"2046 s","price":364.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0560\/1047\/3508\/files\/EE1E4F52-B719-443D-836C-E82373997549.jpg?v=1792006579","url":"https:\/\/yorkshirefossils.net\/products\/peronoceras-fibulatum-ammonite-fossil-with-box-and-stand-whitby-north-yorkshire-jurassic-coast-yorkshire-fossils-copy","provider":"Yorkshire.Fossils","version":"1.0","type":"link"}