The Phyllospondyli is a now abandoned term for a series of small, poorly ossified fossils of

labyrinthodont "Labyrinthodontia" (Greek, 'maze-toothed') is an informal grouping of extinct predatory amphibians which were major components of ecosystems in the late Paleozoic and early Mesozoic eras (about 390 to 150 million years ago). Traditionally conside ...

amphibians from the

Paleozoic The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma a ...

. The groups was proposed as an

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

on the basis if their vertebrae, which was either consisting of

neural arch Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal ...

es over an otherwise unossified

notocord The notochord is an elastic, rod-like structure found in chordates. In vertebrates the notochord is an embryonic structure that disintegrates, as the vertebrae develop, to become the nucleus pulposus in the intervertebral discs of the vertebra ...

or consisting of thin-walled, ring-shaped intercentra topped by the neural arch. The name ''pyllospondily'' is from

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

, "leaf vertebrae".Case, E.C. (1946): A Census of the determinable Genera of Stegocephalia. ''

Transactions of the American Philosophical Society The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...

'', vol. 35, Part 4, pp 325-42
Phyllospondyli section of article
/ref> While the group originally was based on the shape of the vertebrae, common in older classification of labyrinthodonts, several families was at times assigned to it based on skull characters. All members were more or less

salamander Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All t ...

-like in body outline, with weak, poorly ossified limbs, four fingers to the hand and a more or less round

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

when seen from above. Remains of larval

gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

s were frequently found. What animals was actually assigned to the group varies, Case (1946) gave four families that he confidently assigned to the order:

Branchiosauridae Branchiosauridae is an extinct family of small amphibamiform temnospondyls with external gills and an overall juvenile appearance. The family has been characterized by hundreds of well-preserved specimens from the Permo-Carboniferous of Middle ...

(now known to be larval

Temnospondyli Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') or temnospondyls is a diverse ancient order of small to giant tetrapods—often considered primitive amphibians—that flourished ...

), Eugyrinidae (various temnospondyl and

anthracosaur Anthracosauria is a paraphyletic order of extinct reptile-like amphibians (in the broad sense) that flourished during the Carboniferous and early Permian periods, although precisely which species are included depends on one's definition of the ...

groups), Melanerpetontidae and Microbatrachidae (now abandoned). The group as a whole seem to have been a

wastebasket taxon Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon) is a term used by some taxonomists to refer to a taxon that has the purpose of classifying organisms that do not fit anywhere else. They are typically defined by e ...

for various small, poorly ossified and/or larval fossils, the families once ascribed to it largely being constructed from similar animals found in different parts of the world.

References

History of paleontology Stegocephali Polyphyletic groups {{Paleo-tetrapodomorph-stub