NMITA:Neogene Marine Biota of Tropical America

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Thysanus excentricus Duncan, 1863

Holotype: BM(NH) B.M.46814

Morphologic Description:

Meander series sinuosity: gently curved

Colony size: small (<10cm)

Attachment of skeleton: free-living

Epitheca: absent

Wall development between buds: never

Symmetry of bud geometry: uni-directional

Calice or valley width: large (10-15mm)

Calice relief: medium (2-4mm)

Calicular platform shape: v-shaped

Coenosteum: absent

Exothecal dissepiments: absent

Number of septal cycles: >3

Septal spacing (per 5mm): 6-12

Relative septa thickness: equal

Relative costae thickness: equal

Septal lobes: absent

Paliform lobes: present

Columella continuity: continuous

Columella width: <=1/4

Endothecal dissepiments: rare

Wall structure: parathecal

Double or single wall: single

Distribution:

Late Miocene to Early Pliocene : Gurabo Fm., Rio Gurabo, Dominican Republic; Gurabo Fm., Rio Gurabo, Dominican Republic; Gurabo Fm., Rio Gurabo, Dominican Republic;

Early Pliocene : Gurabo Fm., Rio Cana, Dominican Republic; Gurabo Fm., Rio Cana, Dominican Republic;

Early Pliocene to Late Pliocene : Tamiami Fm., Sarasota, Florida;

Early Pliocene to Early Pleistocene : La Cruz Fm., Guantanamo Basin, Cuba; Matanzas Fm., Rio Yumuri, Cuba;

Late Pliocene : Bowden Fm., Bowden Shell Beds, Jamaica; Bowden Fm., Bowden seacliff, Jamaica;

Late Pliocene to Early Pleistocene : 445-484fbmp, BDP Core Clino, Bahamas; 'Old Pera' beds, Pera Point, Jamaica;