Echinochimaera curva
Itano, 2026
Classification: Holocephali Chimaeriformes Echinochimaeridae
Reference of the original description
Five new holocephalan ichthyodorulites from the Viséan (Middle Mississippian) St. Louis Formation of Indiana, USA, including the fin spine of a new echinochimaerid. Canadian Journal of Zoology, 104, in press
Five new holocephalan ichthyodorulites from the Viséan (Middle Mississippian) St. Louis Formation of Indiana, USA, including the fin spine of a new echinochimaerid. Canadian Journal of Zoology, 104, in press
Description:
Citation: Echinochimaera curva Itano, 2026: In: Database of fossil elasmobranch teeth www.shark-references.com, World Wide Web electronic publication, Version 04/2026
Description
Diagnosis after Itano, 2026 [35838]: Spine very narrow compared to width, tapering distally. Gently curved. Basal attachment not known. Preserved length 19 mm (measured from point to point, not following the curve). Preserved width decreases distally from 2.3 to 1.1 mm. Longitudinal ribs on lateral face increase in number from four to five proximally. Single row of pointed denticles on concave margin. Size of denticles increases distally. Spacing between denticles decreases distally. The most proximaldenticles are shortandpointdistally. Thefivedenticles in the most distal one-fifth of the spine length are much longer than the moreproximalones, are narrower than their length, are separated by less than their length, andarelonger than the width of the spine near the distal end. Their orientation varies from nearly perpendicular to the shaft to distal. The length of the longest denticle is 1.9 mm.
Diagnosis after Itano, 2026 [35838]: Spine very narrow compared to width, tapering distally. Gently curved. Basal attachment not known. Preserved length 19 mm (measured from point to point, not following the curve). Preserved width decreases distally from 2.3 to 1.1 mm. Longitudinal ribs on lateral face increase in number from four to five proximally. Single row of pointed denticles on concave margin. Size of denticles increases distally. Spacing between denticles decreases distally. The most proximaldenticles are shortandpointdistally. Thefivedenticles in the most distal one-fifth of the spine length are much longer than the moreproximalones, are narrower than their length, are separated by less than their length, andarelonger than the width of the spine near the distal end. Their orientation varies from nearly perpendicular to the shaft to distal. The length of the longest denticle is 1.9 mm.
Remarks
shark-references Species-ID=17807
shark-references Species-ID=17807
References
Five new holocephalan ichthyodorulites from the Viséan (Middle Mississippian) St. Louis Formation of Indiana, USA, including the fin spine of a new echinochimaerid. Canadian Journal of Zoology, 104, in press
DOI: 10.1139/cjz-2025-0147
Five new holocephalan ichthyodorulites from the Viséan (Middle Mississippian) St. Louis Formation of Indiana, USA, including the fin spine of a new echinochimaerid. Canadian Journal of Zoology, 104, in press
DOI: 10.1139/cjz-2025-0147
