Cayo Agua Island (Pliocene of Panama)

Where: Bocas del Toro, Panama (9.1° N, 82.0° W: paleocoordinates 9.0° N, 81.4° W)

• coordinate estimated from map

When: Cayo Agua Formation, Zanclean (5.3 - 3.6 Ma)

• Underlying/Overlying/Equivalent Unit(s): The Cayo Agua Formation is equivalent in age to the upper part of the Shark Hole Point and the lower part of the Escudo de Veraguas Formations and represents a shallower water facies. No contacts are known. Thickness: 293 m according to Section 19 in Coates (1999). (From LeBlanc 2021).

Environment/lithology: marine; bioturbated, coarse-grained, pebbly, volcaniclastic, shelly/skeletal, muddy, silty sandstone

• The formation as a whole represents shallow onshore and offshore siliciclastic shelf sediments deposited anywhere between 10-80 m. The lack of discernible bedding, with mollusks being deposited in all different orientations, suggests a slump deposit from the post-mortem transport of mixed assemblages from various paleoenvironments. Middle neritic conditions and carbonate shoal have also been suggested. (Todd and Collins, 2005; Vermeij and Collins, 1988; Coates et al., 2005; Collins et al., 1993).
• This locality is in the upper part of the Cayo Agua Formation. It consists lithologically of pervasively bioturbated, muddy, shelly, pebbly, silty sandstone with common horizons of abundant thick-shelled mollusks and ahermatypic corals. Occasional horizons of pebble conglomerate and very coarse grained volcaniclastic sandstone are common in the middle of the formation. Compared to the Shark Hole and Escudo de Veraguas formations, the Cayo Agua Formation is consistently coarser-grained, with common basalt grains and granules, phosphatic pebbles, and wood fragments. A distinctive marker bed of corals occurs near the top of the formation and is well exposed at Tiburon Point and the unnamed point to the south. (Coates et al., 2005; Todd and Collins, 2005).

Size class: macrofossils

Primary reference: J. A. Todd and J. S. H. Collins. 2005. Neogene and Quaternary crabs (Crustacea, Decapoda) collected from Costa Rica and Panama by members of the Panama Paleontology Project. Bulletin of the Mizunami Fossil Museum 32:53-85 [A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 228688: authorized by Joanna Wolfe, entered by Arthur Lynch on 28.12.2022

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Malacostraca
 Decapoda - Aethridae
Hepatus lineatinus
Hepatus lineatinus Todd and Collins 2005 crab
 Decapoda - Leucosiidae
Leucosilia bananensis
Leucosilia bananensis Rathbun 1918 crab
 Decapoda - Portunidae
Sandomingia yaquiensis, Euphylax maculatus
Sandomingia yaquiensis Rathbun 1919 swimming crab
Euphylax maculatus Collins 2005 swimming crab