Synechodus dereki
Cappetta, Morrison & Adnet, 2019
Classification: Elasmobranchii Synechodontiformes Palaeospinacidae
Reference of the original description
A shark fauna from the Campanian of Hornby Island, British Columbia, Canada: an insight into the diversity of Cretaceous deep-water assemblages. Historical Biology, 33(8), 1121–1182
A shark fauna from the Campanian of Hornby Island, British Columbia, Canada: an insight into the diversity of Cretaceous deep-water assemblages. Historical Biology, 33(8), 1121–1182
Description:
Citation: Synechodus dereki Cappetta, Morrison & Adnet, 2019: In: Database of fossil elasmobranch teeth www.shark-references.com, World Wide Web electronic publication, Version 08/2026
Please send your images of "Synechodus dereki" to info@shark-references.com
Synechodus dereki Cappetta, Morrison & Adnet, 2019, Late Cretaceous, Late Campanian, Northumberland Formation, Nanalmo Group, Collishaw Point, Hornby Island, Canada, collection and © Adam Anderson
Synechodus dereki Cappetta, Morrison & Adnet, 2019, Late Cretaceous, Late Campanian, Northumberland Formation, Nanalmo Group, Collishaw Point, Hornby Island, Canada, collection and © Adam Anderson
Description
Original diagnosis after Cappetta, Morrison & Adnet, 2019 [27810]: Teeth characterised by a not overly high and rather slender central cusp. Base of the labial face of the crown overhanging the root by a not very salient bulge covered at its base by numerous short and close vertical folds. The heels are not high and slightly oblique, even in anterior teeth. The heels bear up to five not overly high cusplets, sharp and hook-shaped, slightly bent lingually and towards the cusp. The labial face of the cusplets is smooth except at their extreme base. The lingual face of the cusp is very convex transversely, with folds similar with those covering the labial bulge, and occupying the basal third of it height. In more lateral teeth, the cusplets are more erect. The root is not thick and slightly arched, with a flat basal face except a transversely narrow labial area showing an alternation of furrows and protuberances labio-lingually oriented. This area stops before the marginal parts of the root. In profile view, the angle between the lingual face of the cusp and the lingual protuberance is more than 90°. The lingual protuberance is crossed by labiolingually oriented ducts opening by rather large elliptical foramina labially and in the basal area where the alternance of furrows and protuberances cut out the root.
Original diagnosis after Cappetta, Morrison & Adnet, 2019 [27810]: Teeth characterised by a not overly high and rather slender central cusp. Base of the labial face of the crown overhanging the root by a not very salient bulge covered at its base by numerous short and close vertical folds. The heels are not high and slightly oblique, even in anterior teeth. The heels bear up to five not overly high cusplets, sharp and hook-shaped, slightly bent lingually and towards the cusp. The labial face of the cusplets is smooth except at their extreme base. The lingual face of the cusp is very convex transversely, with folds similar with those covering the labial bulge, and occupying the basal third of it height. In more lateral teeth, the cusplets are more erect. The root is not thick and slightly arched, with a flat basal face except a transversely narrow labial area showing an alternation of furrows and protuberances labio-lingually oriented. This area stops before the marginal parts of the root. In profile view, the angle between the lingual face of the cusp and the lingual protuberance is more than 90°. The lingual protuberance is crossed by labiolingually oriented ducts opening by rather large elliptical foramina labially and in the basal area where the alternance of furrows and protuberances cut out the root.
References
Global impact and selectivity of the Cretaceous-Paleogene mass extinction among sharks, skates, and rays. Science, 379, 802–806
DOI: 10.1126/science.abn2080
A shark fauna from the Campanian of Hornby Island, British Columbia, Canada: an insight into the diversity of Cretaceous deep-water assemblages. Historical Biology, 33(8), 1121–1182
DOI: 10.1080/08912963.2019.1681421
Global impact and selectivity of the Cretaceous-Paleogene mass extinction among sharks, skates, and rays. Science, 379, 802–806
DOI: 10.1126/science.abn2080
A shark fauna from the Campanian of Hornby Island, British Columbia, Canada: an insight into the diversity of Cretaceous deep-water assemblages. Historical Biology, 33(8), 1121–1182
DOI: 10.1080/08912963.2019.1681421
