''Palibacus praecursor'' is a

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

slipper lobster Slipper lobsters are a family (biology), family (Scyllaridae) of about 90 species of Achelata, achelate crustaceans, in the Decapoda clade Reptantia, found in all warm oceans and seas. They are not lobster, true lobsters, but are more closely rel ...

, the only species in the genus ''Palibacus''. It was found in

Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...

(

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

) deposits at Hakel,

Lebanon Lebanon, officially the Republic of Lebanon, is a country in the Levant region of West Asia. Situated at the crossroads of the Mediterranean Basin and the Arabian Peninsula, it is bordered by Syria to the north and east, Israel to the south ...

and described in 1886 by the German

palaeontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

W. Dames. Its similarity to modern slipper lobsters demonstrates that the main features of that group had already

evolved Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

by the mid-Cretaceous.

References

Achelata Late Cretaceous crustaceans Monotypic decapod genera Late Cretaceous arthropods of Asia Cretaceous Lebanon Fossils of Lebanon Cenomanian genera Fossil taxa described in 1984 Prehistoric crustacean genera {{Decapoda-stub