''Eusauropleura'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of gephyrostegid

tetrapodomorph Tetrapodomorpha (also known as Choanata) is a clade of vertebrates consisting of tetrapods (four-limbed vertebrates) and their closest sarcopterygian relatives that are more closely related to living tetrapods than to living lungfish. Advanced for ...

from the Pennsylvanian (Late

Carboniferous The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...

) of Linton, Ohio. The type species and only species, ''Eusauropleura digitata'', was first described by American paleontologist

Edward Drinker Cope Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American zoologist, paleontology, paleontologist, comparative anatomy, comparative anatomist, herpetology, herpetologist, and ichthyology, ichthyologist. Born to a wealthy Quaker fam ...

in 1868 as ''Sauropleura digitata''. In 1930, paleontologist

Alfred Romer Alfred Sherwood Romer (December 28, 1894 – November 5, 1973) was an American paleontologist and biologist and a specialist in vertebrate evolution. Biography Alfred Romer was born in White Plains, New York, the son of Harry Houston Romer an ...

placed the species in the new genus ''Eusauropleura''. Romer considered ''S. digitata'' to be a reptile or a more primitive relative of reptiles, making it only distantly related to ''

Sauropleura ''Sauropleura'' (meaning "lizard side") is an extinct genus of nectridean tetrapodomorphs within the family Urocordylidae The Urocordylidae are an extinct family (biology), family of nectridean lepospondyl amphibians. Urocordylids lived during ...

'', which is a

lepospondyl Lepospondyli is a diverse clade of early tetrapods. With the exception of one late-surviving lepospondyl from the Late Permian of Morocco ('' Diplocaulus minimus''), lepospondyls lived from the Visean stage of the Early Carboniferous to the Earl ...

amphibian. ''Eusauropleura'' is known from ribs and limb bones, but no skull is known. The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

fossil is preserved in ventral view with a dense coating of small scales covering its underside. The arms and legs are nearly complete. It is similar in appearance to '' Gephyrostegus'' from the

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

, with closely matching body proportions. Compared to ''Gephyrostegus'', ''Eusauropleura'' has a more weakly

ossified Ossification (also called osteogenesis or bone mineralization) in bone remodeling is the process of laying down new bone material by cells named osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in t ...

pelvis. The hand has five fingers with a phalangeal count of 2, 3, 4, 5, 4, meaning there are 2 bones in the first finger, 3 in the second, 4 in the third, 5 in the fourth, and 4 in the fifth. Romer used the phalangeal count as evidence that ''E. digitata'' was distinct from ''Sauropleura'', since lepospondyls like ''Sauropleura'' only have four fingers on each hand.

References

Stegocephali Carboniferous tetrapods of North America {{tetrapodomorph-stub