Chordata

Chordata

47 specimens 4 localities

Geological time

Triassic Jurassic Cretaceous Pal Eocene Ol Miocene

Late Cretaceous · 100–94 million years ago Kem Kem Group (Gara Sbaa & Douira Formations) 🇲🇦

Kem Kem

7 specimens

Bone fragment - Measurement ~3cm

5

Bone - Measurement ~3cm

11

Bone - Measurement ~3cm

Bone

Bone

Bone

Bone

Bone

Bone

Bone

Bone

Bone

Bone

Unknown, perhaps bone fragment - Measurement ~2cm

5

Unknown, perhaps bone fragment - Measurement ~2cm

6

Unknown, perhaps bone fragment - Measurement ~1.5cm

2

Bone fragment - ~1cm

4

Bone fragment - ~1cm

3

Lower Eocene · ~54.5 million years ago Harwich Formation (Blackheath Beds) 🏴󠁧󠁢󠁥󠁮󠁧󠁿

Lesnes Abbey, Abbey Wood, London

24 specimens

Vertebra - measurement ~0.8cm

5

Vertebra - measurement ~0.8cm

6

Vertebra - measurement ~0.9cm

6

Vertebra - measurement ~0.4cm length

4

Vertebra - measurement ~0.9cm

5

Vertebra - measurement ~0.4cm

6

Vertebra - measurement ~0.9cm

6

Vertebra - measurement ~1cm

4

Vertebra - measurement ~0.6cm (diameter)

7

Vertebra - measurement ~0.6cm (diameter)

Vertebra - measurement ~0.7cm (length)

Vertebra

Vertebra

Vertebra

Vertebra

Vertebra

Vertebra - measurement ~0.7cm

5

Vertebra - measurement ~0.4cm

5

Vertebra - measurement ~0.1cm

5

Vertebra(?) - measurement ~0.6cm

5

Vertebra, broken in the middle - measurement ~0.6cm

5

Vertebra - measurement ~0.6cm

6

Vertebra, very weathered - measurement ~0.5cm

3

Vertebra - measurement ~0.4cm

4

Vertebra, very weathered - measurement ~0.7cm

5

Vertebra, very weathered - measurement ~0.6cm

5

Vertebra, very weathered - measurement ~0.3cm

4

Bone, broken - measurement 2.5-3cm

6

Bone fragment - measurement ~1cm

7

Bone fragment - measurement ~1cm

Bone fragment

Bone fragment

Bone fragment

Bone fragment - internal structure visible

Bone fragment - internal structure visible

Bone fragment - internal structure visible

Bone fragment - measurement ~1cm

6

Bone fragment - measurement ~0.9cm

3

Middle Miocene · 13.6–11.6 million years ago Pakhna Formation 🇨🇾

Lefkothea

1 specimen

Scale

Middle Miocene · 13.6–11.6 million years ago Pakhna Formation 🇨🇾

Alassa

15 specimens

Spine and (?)fins

Scale and (?)plant remains

Spine and (?)head

Spine and (?)head

Spine and (?)part of body

Scales (from a tail?)

2

Spine and (?)head

Scales (of a fish?), elongated shape. 7 fragments

9

Scales (of a fish?), elongated shape. 7 fragments

3 large fragments

Large fragments. Side Α

Large fragment. Side B

Small fragments

Small fragment A, detail

Small fragment B, detail

Small fragment C, detail

Small fragment D, detail

Spine and (?)head

Scales

Scale

2

4

Scale + negative impression

3

Fish tail

View A

4

chordata

Chordates are defined by four key features: a notochord (supporting rod), a dorsal hollow nerve cord (brain and spinal cord), pharyngeal slits (throat openings), and a post-anal tail. These traits may only appear during embryonic development, but their presence at any point classifies an animal as a chordate, a diverse group including vertebrates and some invertebrates.

Subtaxa

Chondrichthyes

Osteichthyes