Essexraja ypresiensis
Reinecke, Mollen, Gijsen, D’Haeze & Hoedemakers, 2024
Classification: Elasmobranchii Rajiformes incert. fam.
Reference of the original description
Batomorphs (Elasmobranchii: Rhinopristiformes, Rajiformes, Torpediniformes, Myliobatiformes) of the middle to late Ypresian, early Eocene, in the Anglo-Belgian Basin (south-western North Sea Basin) – a review and description of new taxa. Palaeontos, 35, 1–172
Batomorphs (Elasmobranchii: Rhinopristiformes, Rajiformes, Torpediniformes, Myliobatiformes) of the middle to late Ypresian, early Eocene, in the Anglo-Belgian Basin (south-western North Sea Basin) – a review and description of new taxa. Palaeontos, 35, 1–172
Types
Essexraja ypresiensis
Holotype: SMF(fossil): P 11986; Paratype: SMF(fossil): P 11985; SMF(fossil): P 11989; SMF(fossil): P 11990; SMF(fossil): P 11991; SMF(fossil): P 11992; SMF(fossil): P 11993; SMF(fossil): P 11994; SMF(fossil): P 11995; SMF(fossil): P 11996; SMF(fossil): P 11999;
Essexraja ypresiensis
Holotype: SMF(fossil): P 11986; Paratype: SMF(fossil): P 11985; SMF(fossil): P 11989; SMF(fossil): P 11990; SMF(fossil): P 11991; SMF(fossil): P 11992; SMF(fossil): P 11993; SMF(fossil): P 11994; SMF(fossil): P 11995; SMF(fossil): P 11996; SMF(fossil): P 11999;
Description:
Citation: Essexraja ypresiensis Reinecke, Mollen, Gijsen, D’Haeze & Hoedemakers, 2024: In: Database of fossil elasmobranch teeth www.shark-references.com, World Wide Web electronic publication, Version 08/2026
Description
Original diagnosis after Reinecke, Mollen, Gijsen, D’Haeze & Hoedemakers, 2024 [32774]: Rajoid species defined by isolated teeth, 0.9-ca 2.5 mm high and 0.9-1.5 mm wide; gradient-monognathic and sexual heterodonty clearly recognizable. Teeth of male morphology in probably anterior to anterolateral files moderately high, upright to slightly distally oblique. Triangular cusp with pointed apex, distinctly inclined in lingual direction. Transverse mesial/distal cutting ridges sharp and long, extending from the apex to basal crown margins, straight or concave at the cusp and convex at the crown base. Axial labial ridge absent. Labial crown surface smooth and rather flat on upper crown, but mesio-distally convex on lower region. Contour of crown base in occlusal view elliptical to rhomboid, with evenly convex labial visor and even more convex lingual visor lacking an uvula. Apron absent. Latero-labial basal crown surface fairly long and convex; transverse collar on labial side of the root-crown junction moderately deep but long. Teeth of more distal (?lateral to commissural) files with proportionally lower crown, wider crown base, and a very shallow to concave labial crown surface. Root holaulacorhize, moderately high, with laterally divergent lobes, being nearly as wide as or narrower than basal marginal crown; foramina on latero-lingual root surfaces absent; nutritive groove deep, uniformly wide or wedge-shaped (in lateroposterior teeth only), with 1- 3 larger foramina.
Teeth of female morph dimensionally similar to those of male morph, but with lower, much less pointed crown; labial surface oval- to triangular-shaped, flattened; transverse cutting ridge lingually convex to V-shaped (in occlusal view), displaying commonly an asymmetric apex. Crown base in profile view rather straight (as in male teeth), apron absent, and uvula weakly developed or absent. Root similar as in male teeth but lobes mesio-distally and labiolingually often narrower than the crown base.
Original diagnosis after Reinecke, Mollen, Gijsen, D’Haeze & Hoedemakers, 2024 [32774]: Rajoid species defined by isolated teeth, 0.9-ca 2.5 mm high and 0.9-1.5 mm wide; gradient-monognathic and sexual heterodonty clearly recognizable. Teeth of male morphology in probably anterior to anterolateral files moderately high, upright to slightly distally oblique. Triangular cusp with pointed apex, distinctly inclined in lingual direction. Transverse mesial/distal cutting ridges sharp and long, extending from the apex to basal crown margins, straight or concave at the cusp and convex at the crown base. Axial labial ridge absent. Labial crown surface smooth and rather flat on upper crown, but mesio-distally convex on lower region. Contour of crown base in occlusal view elliptical to rhomboid, with evenly convex labial visor and even more convex lingual visor lacking an uvula. Apron absent. Latero-labial basal crown surface fairly long and convex; transverse collar on labial side of the root-crown junction moderately deep but long. Teeth of more distal (?lateral to commissural) files with proportionally lower crown, wider crown base, and a very shallow to concave labial crown surface. Root holaulacorhize, moderately high, with laterally divergent lobes, being nearly as wide as or narrower than basal marginal crown; foramina on latero-lingual root surfaces absent; nutritive groove deep, uniformly wide or wedge-shaped (in lateroposterior teeth only), with 1- 3 larger foramina.
Teeth of female morph dimensionally similar to those of male morph, but with lower, much less pointed crown; labial surface oval- to triangular-shaped, flattened; transverse cutting ridge lingually convex to V-shaped (in occlusal view), displaying commonly an asymmetric apex. Crown base in profile view rather straight (as in male teeth), apron absent, and uvula weakly developed or absent. Root similar as in male teeth but lobes mesio-distally and labiolingually often narrower than the crown base.
Remarks
shark-references Species-ID=17208
shark-references Species-ID=17208
References
Batomorphs (Elasmobranchii: Rhinopristiformes, Rajiformes, Torpediniformes, Myliobatiformes) of the middle to late Ypresian, early Eocene, in the Anglo-Belgian Basin (south-western North Sea Basin) – a review and description of new taxa. Palaeontos, 35, 1–172
Batomorphs (Elasmobranchii: Rhinopristiformes, Rajiformes, Torpediniformes, Myliobatiformes) of the middle to late Ypresian, early Eocene, in the Anglo-Belgian Basin (south-western North Sea Basin) – a review and description of new taxa. Palaeontos, 35, 1–172
