Editing Carboniferous (section)

==Life==

===Plants===
[[File:Meyers b15 s0272b.jpg|thumb|upright|Etching depicting some of the most significant plants of the Carboniferous]]
Early Carboniferous land plants, some of which were [[permineralisation|preserved]] in [[coal ball]]s, were very similar to those of the preceding Late Devonian, but new groups also appeared at this time. The main early Carboniferous plants were the [[Equisetales]] (horse-tails), [[Sphenophyllales]] (scrambling plants), [[Lycopodiales]] (club mosses), [[Lepidodendrales]] (scale trees), [[Filicales]] (ferns), [[Medullosales]] (informally included in the "[[Pteridospermatophyta|seed ferns]]", an assemblage of a number of early [[gymnosperm]] groups) and the [[Cordaitales]]. These continued to dominate throughout the period, but during the late Carboniferous, several other groups, [[Cycadophyta]] (cycads), the [[Callistophytales]] (another group of "seed ferns"), and the [[Voltziales]], appeared.
[[File:Lycopsid joggins mcr1.JPG|thumb|left|Ancient ''in situ'' [[w:lycopsid|lycopsid]], probably ''[[w:Sigillaria|Sigillaria]]'', with attached [[w:stigmaria|stigmarian roots]], [[Joggins Formation]], Canada]]
[[File:Lycopsid mcr2.jpg|thumb|left|Base of a [[w:lycopsid|lycopsid]] showing connection with bifurcating [[w:Stigmaria|stigmarian]] roots]]
The Carboniferous lycophytes of the order Lepidodendrales, which are cousins (but not ancestors) of the tiny club-moss of today, were huge trees with trunks 30 meters high and up to 1.5 meters in diameter. These included ''[[Lepidodendron]]'' (with its cone called [[Lepidostrobus]]), ''[[Anabathra (plant)|Anabathra]]'', ''[[Lepidophloios]]'' and ''[[Sigillaria]]''.{{sfn|Howe|1911|p=311}} The roots of several of these forms are known as [[Stigmaria]]. Unlike present-day trees, their [[secondary growth]] took place in the [[Cortex (botany)|cortex]], which also provided stability, instead of the [[xylem]].{{sfn|Westfälische Wilhelms-Universität Münster|2012}} The [[Cladoxylopsida|Cladoxylopsids]] were large trees, that were ancestors of ferns, first arising in the Carboniferous.{{sfn|Hogan|2010}}

{{AmCyc Poster|Coal Plants}}

The fronds of some Carboniferous ferns are almost identical with those of living species. Probably many species were [[Epiphyte|epiphytic]]. Fossil ferns and "seed ferns" include ''[[Pecopteris]]'', ''[[Cyclopteris]]'', ''[[Neuropteris]]'', ''[[Alethopteris]]'', and ''[[Sphenopteris]]''; ''[[Megaphyton]]'' and ''[[Caulopteris]]'' were tree ferns.{{sfn|Howe|1911|p=311}}

The Equisetales included the common giant form ''[[Calamites]]'', with a trunk diameter of 30 to {{convert|60|cm|0|abbr=on}} and a height of up to {{convert|20|m|0|abbr=on}}. ''[[Sphenophyllum]]'' was a slender climbing plant with whorls of leaves, which was probably related both to the calamites and the lycopods.{{sfn|Howe|1911|p=311}}

''[[Cordaites]]'', a tall plant (6 to over 30 meters) with strap-like leaves, was related to the cycads and conifers; the [[catkin]]-like reproductive organs, which bore ovules/seeds, is called ''[[Cardiocarpus]]''. These plants were thought to live in swamps. True coniferous trees (''[[Walchia]]'', of the order Voltziales) appear later in the Carboniferous,{{sfn|Howe|1911|p=311}} and preferred higher drier ground.

===Marine invertebrates===
In the oceans the [[marine invertebrate]] groups are the [[Foraminifera]], [[Anthozoa|corals]], [[Bryozoa]], [[Ostracoda]], [[brachiopod]]s, [[Ammonoidea|ammonoids]], [[hederellid|hederelloids]], [[microconchids]] and [[echinoderm]]s (especially [[crinoid]]s).{{Citation needed|date=September 2022}} The diversity of brachiopods and fusilinid foraminiferans, surged beginning in the [[Visean]], continuing through the end of the Carboniferous, although cephalopod and nektonic conodont diversity declined. This evolutionary radiation was known as the Carboniferous-Earliest Permian Biodiversification Event.<ref>{{cite journal |last1=Shi |first1=Yukun |last2=Wang |first2=Xiangdong |last3=Fan |first3=Junxuan |last4=Huang |first4=Hao |last5=Xu |first5=Huiqing |last6=Zhao |first6=Yingying |last7=Shen |first7=Shuzhong |date=September 2021 |title=Carboniferous-earliest Permian marine biodiversification event (CPBE) during the Late Paleozoic Ice Age |url=https://www.sciencedirect.com/science/article/pii/S0012825221002002 |journal=Earth-Science Reviews |volume=220 |page=103699 |doi=10.1016/j.earscirev.2021.103699 |bibcode=2021ESRv..22003699S |access-date=24 August 2022}}</ref> For the first time foraminifera took a prominent part in the marine faunas. The large spindle-shaped genus [[Fusulinida|Fusulina]] and its relatives were abundant in what is now Russia, China, Japan, North America; other important genera include ''Valvulina'', ''Endothyra'', ''Archaediscus'', and ''Saccammina'' (the latter common in Britain and Belgium). Some Carboniferous genera are still [[Extant taxon|extant]]. The first true [[priapulid]]s appeared during this period.{{sfn|Howe|1911|p=311}}

The microscopic shells of [[radiolaria]]ns are found in [[chert]]s of this age in the [[Culm Measures|Culm]] of [[Devon]] and [[Cornwall]], and in Russia, Germany and elsewhere. [[Porifera|Sponges]] are known from [[spicule (sponge)|spicule]]s and anchor ropes,{{sfn|Howe|1911|p=311}} and include various forms such as the Calcispongea ''Cotyliscus'' and ''Girtycoelia'', the [[demosponge]] ''Chaetetes'', and the genus of unusual colonial [[Hexactinellid|glass sponges]] ''[[Titusvillia]]''. Both [[reef]]-building and solitary corals diversify and flourish; these include both [[Rugosa|rugose]] (for example, ''[[Caninia (genus)|Caninia]]'', ''Corwenia'', ''Neozaphrentis''), heterocorals, and [[Tabulata|tabulate]] (for example, ''Chladochonus'', ''Michelinia'') forms. [[Conularids]] were well represented by ''Conularia''

[[Bryozoa]] are abundant in some regions; the fenestellids including ''Fenestella'', ''Polypora'', and ''[[Archimedes (bryozoan)|Archimedes]]'', so named because it is in the shape of an [[Archimedean screw]]. [[Brachiopod]]s are also abundant;<ref>{{cite journal |last1=Pérez-Huerta |first1=Alberto |last2=Sheldon |first2=Nathan D. |date=30 January 2006 |title=Pennsylvanian sea level cycles, nutrient availability and brachiopod paleoecology |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018205004451 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=230 |issue=3–4 |pages=264–279 |doi=10.1016/j.palaeo.2005.07.020 |bibcode=2006PPP...230..264P |access-date=31 March 2023}}</ref> they include [[Productida|productids]], some of which reached very large for brachiopods size and had very thick shells (for example, the {{cvt|30|cm}}-wide ''[[Gigantoproductus]]''<ref name=Hall2004>{{cite book
| url         = https://books.google.com/books?id=65Bdfy-SOyMC&dq=largest+Gigantoproductus&pg=PA87
| title       = Environment, Development, and Evolution. Toward a Synthesis
| publisher   = MIT Press
| date        = 2004
| access-date  = 2022-08-23
| page        = 87
|first1= Brian Keith |last1=Hall|first2=Gerd B. |last2=Müller|first3=Roy Douglas |last3=Pearson
| isbn = 9780262083195
}}</ref><ref>{{cite book
| url         = https://books.google.com/books?id=bL60DwAAQBAJ&dq=largest+Gigantoproductus+giganteus&pg=PA47
| title       = Convergent Evolution on Earth. Lessons for the Search for Extraterrestrial Life
| publisher   = MIT Press
| date        = 2019
| access-date  = 2022-08-23
| page        = 47
| author      = George R. McGhee, Jr.
| isbn = 9780262354189
}}</ref>), while others like ''[[Chonetes]]'' were more conservative in form. [[Athyridida|Athyridids]], [[Spiriferida|spiriferids]], [[Rhynchonellida|rhynchonellids]], and [[Terebratulida|terebratulids]] are also very common. Inarticulate forms include ''[[Discina (brachiopod)|Discina]]'' and ''[[Crania (genus)|Crania]]''. Some species and genera had a very wide distribution with only minor variations.

[[Annelid]]s such as ''Serpulites'' are common fossils in some horizons. Among the mollusca, the [[bivalve]]s continue to increase in numbers and importance. Typical genera include ''[[Aviculopecten]]'', ''[[Posidonomya]]'', ''[[Nucula]]'', ''[[Carbonicola (bivalve)|Carbonicola]]'', ''Edmondia'', and ''Modiola''. [[Gastropod]]s are also numerous, including the genera ''Murchisonia'', ''[[Euomphalus]]'', ''Naticopsis''.{{sfn|Howe|1911|p=311}} [[Nautiloid]] [[cephalopod]]s are represented by tightly coiled [[Nautilida|nautilids]], with straight-shelled and curved-shelled forms becoming increasingly rare. [[Goniatite]] [[Ammonoidea|ammonoids]] such as [[Aenigmatoceras]] are common.

[[Trilobite]]s are rarer than in previous periods, on a steady trend towards extinction, represented only by the [[Proetida|proetid]] group. [[Ostracod]]a, a class of [[crustacean]]s, were abundant as representatives of the [[meiobenthos]]; genera included ''Amphissites'', ''Bairdia'', ''Beyrichiopsis'', ''Cavellina'', ''Coryellina'', ''Cribroconcha'', ''Hollinella'', ''Kirkbya'', ''Knoxiella'', and ''Libumella''. [[Crinoid]]s were highly numerous during the Carboniferous, though they suffered a gradual decline in diversity during the Middle Mississippian.<ref>{{cite journal |last1=Ausich |first1=William I. |last2=Kammer |first2=Thomas W. |last3=Baumiller |first3=Tomasz K. |date=8 February 2016 |title=Demise of the middle Paleozoic crinoid fauna: a single extinction event or rapid faunal turnover? |url=https://www.cambridge.org/core/journals/paleobiology/article/abs/demise-of-the-middle-paleozoic-crinoid-fauna-a-single-extinction-event-or-rapid-faunal-turnover/CCE6603D020FBCE7D793746990C5011A |journal=[[Paleobiology (journal)|Paleobiology]] |volume=20 |issue=3 |pages=345–361 |doi=10.1017/S0094837300012811 |s2cid=140542784 |access-date=21 April 2023}}</ref> Dense submarine thickets of long-stemmed crinoids appear to have flourished in shallow seas, and their remains were consolidated into thick beds of rock. Prominent genera include ''Cyathocrinus'', ''Woodocrinus'', and ''Actinocrinus''. Echinoids such as ''[[Archaeocidaris]]'' and ''Palaeechinus'' were also present. The [[blastoid]]s, which included the Pentreinitidae and Codasteridae and superficially resembled crinoids in the possession of long stalks attached to the seabed, attain their maximum development at this time.{{sfn|Howe|1911|p=311}}

<gallery mode="packed">
File:Aviculopecten subcardiformis01.JPG|''Aviculopecten subcardiformis''; a [[bivalve]] from the [[Logan Formation]] (lower Carboniferous) of [[Wooster, Ohio]] (external mold)
File:LoganFauna011312.jpg|Bivalves (''Aviculopecten'') and brachiopods (''Syringothyris'') in the Logan Formation (lower Carboniferous) in Wooster, Ohio
File:Syringothyris01.JPG|''Syringothyris'' sp.; a spiriferid [[brachiopod]] from the Logan Formation (lower Carboniferous) of Wooster, Ohio (internal mold)
File:Palaeophycus01.JPG|''Palaeophycus'' ichnosp.; a [[trace fossil]] from the Logan Formation (lower Carboniferous) of Wooster, Ohio
File:PlatyceratidMississippian.JPG|[[Crinoid]] calyx from the lower Carboniferous of Ohio with a conical [[Platyceratidae|platyceratid]] gastropod (''Palaeocapulus acutirostre'') attached
File:Conulariid03.jpg|Conulariid from the lower Carboniferous of Indiana
File:Syringoporid.jpg|Tabulate coral (a syringoporid); Boone Limestone (lower Carboniferous) near Hiwasse, Arkansas
File:Typhloesus interpretation 2022.jpg|''[[Typhloesus]]'' was a bizarre invertebrate that lived in Montana. It is possibly a mollusk related to gastropods.
File:Essexella asherae.JPG|''[[Essexella]]'' was a cnidarian that lived in Northern Illinois. It was long considered a [[scyphozoa]]n, but is now regarded as a [[Sea anemone]]
File:Concavicaris georgeorum.png|''Concavicaris'' was a long lasting genus of [[thylacocephala]]n arthropod that lived from the Devonian to the Carboniferous.
File:Triproetus bonbon cropped.jpg|''[[Triproetus]]'' was a genus of [[Proetida|proetid]] trilobite, which were the only order that survived the end-Devonian extinction 
File:Daidal.png|''[[Daidal]]'' was a basal species of Mantis shrimp ([[stomatopoda]])
File:Jeletzkya douglassae.jpg|''[[Jeletzkya]]'' was an early genus of [[Coleoidea|coleoid]] cephalopod from northern [[Illinois]] 
File:Syllipsimopodi bideni.webp|''[[Syllipsimopodi]]'' was the earliest known [[Vampyropoda|vampyropod]] cephalopod, originating from Carboniferous rocks of Montana.
</gallery>

===Freshwater and lagoonal invertebrates===
Freshwater Carboniferous invertebrates include various [[bivalve]] [[mollusc]]s that lived in brackish or fresh water, such as ''Anthraconaia'', ''[[Naiadites]]'', and ''[[Carbonicola (bivalve)|Carbonicola]]''; diverse [[crustacean]]s such as ''[[Candona]]'', ''[[Carbonita (crustacean)|Carbonita]]'', ''[[Darwinula]]'', ''[[Estheria (crustacean)|Estheria]]'', ''Acanthocaris'', ''Dithyrocaris'', and ''Anthrapalaemon''. The [[eurypterid]]s were also diverse, and are represented by such genera as ''[[Adelophthalmus]]'', ''[[Megarachne]]'' (originally misinterpreted as a giant spider, hence its name) and the specialised very large ''[[Hibbertopterus]]''. Many of these were amphibious. Frequently a temporary return of marine conditions resulted in marine or brackish water genera such as ''[[Lingula (genus)|Lingula]]'', ''Orbiculoidea'', and ''[[Productus]]'' being found in the thin beds known as marine bands.

<gallery mode="packed" heights="180">
File:20210116 Megarachne hypothetical reconstruction.png|''Megarachne'' was a large freshwater eurypterid from South America that was originally misidentified as a spider
File:Adelophthalmus irinae.png|''Adelophthalmus'' was the only genus of [[Eurypterina|eurypterine]] eurypterid that survived past the Devonian
File:Hibbertopterus scouleri.jpg|Due to its large and compact shell, ''Hibbertopterus'' was one of if not the heaviest eurypterid in the fossil record
</gallery>

=== Terrestrial invertebrates ===
Fossil remains of air-breathing [[insect]]s,{{sfn|Garwood|Sutton|2010}} [[Myriapoda|myriapod]]s, and [[arachnid]]s{{sfn| Garwood |Dunlop |Sutton |2009}} are known from the Carboniferous. Their diversity when they do appear, however, shows that these arthropods were both well-developed and numerous.<ref name=GrahamAguilarDudleyGans1995>{{cite journal |last1=Graham |first1=Jeffrey B. |last2=Aguilar |first2=Nancy M. |last3=Dudley |first3=Robert |last4=Gans |first4=Carl |date=11 May 1995 |title=Implications of the late Palaeozoic oxygen pulse for physiology and evolution |journal=Nature |volume=375 |issue=6527 |pages=117–120 |doi=10.1038/375117a0 |bibcode=1995Natur.375..117G |hdl=2027.42/62968 |hdl-access=free |s2cid=4308580 |url=https://www.nature.com/articles/375117a0?error=cookies_not_supported&code=23b4f690-2f27-4c0f-928c-5245d4b0d4f6#citeas |access-date=6 November 2022 }}</ref><ref name=CannellEtAl2022>{{cite journal |last1=Cannell |first1=Alan |last2=Blamey |first2=Nigel |last3=Brand |first3=Uwe |last4=Escapa |first4=Ignacio |last5=Large |first5=Ross |date=August 2022 |title=A revised sedimentary pyrite proxy for atmospheric oxygen in the Paleozoic: Evaluation for the Silurian-Devonian-Carboniferous period and the relationship of the results to the observed biosphere record |url=https://www.sciencedirect.com/science/article/abs/pii/S0012825222001465 |journal=[[Earth-Science Reviews]] |volume=231 |page=104062 |doi=10.1016/j.earscirev.2022.104062 |bibcode=2022ESRv..23104062C |s2cid=249298393 |access-date=6 November 2022}}</ref>{{sfn|Verberk|Bilton|2011}} Some arthropods grew to large sizes with the up to {{convert|2.6|m|ft|sp=us|adj=mid|-long}} millipede-like ''[[Arthropleura]]'' being the largest-known land invertebrate of all time. In the mid-Mississippian the oldest known [[Pterygota|winged insects]] appears,<ref>{{cite journal | last1=Schachat | first1=Sandra R | last2=Goldstein | first2=Paul Z | last3=Desalle | first3=Rob | last4=Bobo | first4=Dean M | last5=Boyce | first5=C Kevin | last6=Payne | first6=Jonathan L | last7=Labandeira | first7=Conrad C | title=Illusion of flight? Absence, evidence and the age of winged insects | journal=Biological Journal of the Linnean Society | volume=138 | issue=2 | date=2023-02-02 | issn=0024-4066 | doi=10.1093/biolinnean/blac137 | doi-access=free | pages=143–168 | url=https://academic.oup.com/biolinnean/article-pdf/138/2/143/49055959/blac137.pdf}}</ref>
followed by the huge predatory [[Meganisoptera|Protodonata]] (griffinflies), which includes ''[[Meganeura]]'', a giant [[dragonfly]]-like insect and with a wingspan of ca. {{convert|75|cm|0|abbr=on}}—the largest flying insect ever to roam the planet. Further groups are the Syntonopterodea (relatives of present-day [[Ephemeroptera|mayflies]]), the abundant and often large sap-sucking [[Palaeodictyopteroidea]], the diverse herbivorous [[Protorthoptera]], and numerous [[Basal (phylogenetics)|basal]] [[Dictyoptera]] (ancestors of [[cockroach]]es).{{sfn|Garwood|Sutton|2010}}

Many insects have been obtained from the coalfields of [[Saarbrücken]] and [[Commentry]], and from the hollow trunks of fossil trees in Nova Scotia. Some British coalfields have yielded good specimens: ''Archaeoptilus'', from the Derbyshire coalfield, had a large wing with {{convert|4.3|cm|0|abbr=on}} preserved part, and some specimens (''[[Brodia]]'') still exhibit traces of brilliant wing colors. In the Nova Scotian tree trunks land snails (''[[Archaeozonites]]'', ''[[Dendropupa]]'') have been found.{{sfn|Howe|1911|p=312}}

<gallery mode="packed">
File:Meganeura.png|The late Carboniferous giant dragonfly-like insect ''[[Meganeura]]'' grew to wingspans over {{cvt|60|cm|ftin|0}}.
File:20210116 Pulmonoscorpius kirktonensis.png|The gigantic ''[[Pulmonoscorpius]]'' from the early Carboniferous reached a length of up to {{cvt|70|cm|ftin|0}}.
File:Arthropleura Reconstruction.jpg|''[[Arthropleura]]'' was a giant millipede that fed on the Carboniferous plants. At {{cvt|8|feet|cm}} long, it was the largest terrestrial arthropod that ever lived.
File:Homaloneura ligeia.jpg|''[[Homaloneura]]'', a [[palaeodictyoptera]]n insect which have two winglets on thorax in addition to four wings.
File:Helenodora inopinata.jpg|[[Helenodora|''Helenodora inopinata'']], a [[stem-group]] [[onychophora]]n known from [[Indiana]]
File:Blattoidae - Fossil.JPG|A [[roachoid]] insect found in Carboniferous rocks of France
File:20201202 Maiocercus celticus.png|''[[Maiocercus]]'' was a [[Trigonotarbida|trigonotarbid]] arachnid that lived in the United Kingdom around 310 million years ago.
</gallery>

===Fish===
Many fish inhabited the Carboniferous seas; predominantly [[Elasmobranch]]s (sharks and their relatives). These included some, like ''[[Psammodus]]'', with crushing pavement-like teeth adapted for grinding the shells of brachiopods, crustaceans, and other marine organisms. Other groups of elasmobranchs, like the [[ctenacanthiformes]] grew to large sizes, with some genera like ''[[Saivodus]]'' reaching around {{convert|6|–|9|m|ft|sp=us}}.<ref>{{Cite journal |last=Engelman |first=Russell K. |date=2023 |title=A Devonian Fish Tale: A New Method of Body Length Estimation Suggests Much Smaller Sizes for Dunkleosteus terrelli (Placodermi: Arthrodira) |journal=Diversity |language=en |volume=15 |issue=3 |pages=318 |doi=10.3390/d15030318 |issn=1424-2818 |doi-access=free |bibcode=2023Diver..15..318E }}</ref> Other fish had piercing teeth, such as the [[Symmoriida]]; some, the [[petalodont]]s, had peculiar cycloid cutting teeth. Most of the other cartilaginous fish were marine, but others like the [[Xenacanthida]], and several genera like ''[[Bandringa]]'' invaded fresh waters of the coal swamps.<ref name="Sallan-2014">{{Cite journal |last1=Sallan |first1=Lauren Cole |last2=Coates |first2=Michael I. |date=January 2014 |title=The long-rostrumed elasmobranch Bandringa Zangerl, 1969, and taphonomy within a Carboniferous shark nursery |url=http://www.tandfonline.com/doi/abs/10.1080/02724634.2013.782875 |journal=Journal of Vertebrate Paleontology |language=en |volume=34 |issue=1 |pages=22–33 |doi=10.1080/02724634.2013.782875 |bibcode=2014JVPal..34...22S |issn=0272-4634 |s2cid=86174861}}</ref> Among the [[Osteichthyes|bony fish]], the [[Palaeonisciformes]] found in coastal waters also appear to have migrated to rivers. [[Sarcopterygii|Sarcopterygia]]n fish were also prominent, and one group, the [[Rhizodont]]s, reached very large size.

Most species of Carboniferous marine fish have been described largely from teeth, fin spines and dermal ossicles,{{sfn|Howe|1911|p=311}} with smaller freshwater fish preserved whole. Freshwater fish were abundant, and include the genera ''[[Ctenodus]]'', ''Uronemus'', ''[[Acanthodes]]'', ''Cheirodus'', and ''[[Gyracanthus]]''. [[Chondrichthyes]] (especially [[Holocephali|holocephalans]] like the [[Stethacanthidae|Stethacanthids]]) underwent a major [[evolutionary radiation]] during the Carboniferous.{{sfn|Martin|2008}} It is believed that this evolutionary radiation occurred because the decline of the [[Placodermi|placoderms]] at the end of the Devonian caused many [[Niche (ecology)|environmental niches]] to become unoccupied and allowed new organisms to evolve and fill these niches.{{sfn|Martin|2008}} As a result of the evolutionary radiation Carboniferous holocephalans assumed a wide variety of bizarre shapes including ''[[Stethacanthus]]'' which possessed a flat brush-like dorsal fin with a patch of [[Dermal denticle|denticles]] on its top.{{sfn|Martin|2008}} ''[[Stethacanthus]]''{{'s}} unusual fin may have been used in mating rituals.{{sfn|Martin|2008}}

Other groups like the [[Eugeneodontida|eugeneodonts]] filled in the niches left by large predatory placoderms. These fish were unique as they only possessed one, at most two, rows of teeth in either their upper or lower jaws in the form of elaborate tooth whorls.<ref name="Lebedev20092">{{cite journal |last1=Lebedev |first1=O.A. |year=2009 |title=A new specimen of ''Helicoprion'' Karpinsky, 1899 from Kazakhstanian Cisurals and a new reconstruction of its tooth whorl position and function |url=https://www.researchgate.net/publication/249440368 |journal=Acta Zoologica |volume=90 |pages=171–182 |doi=10.1111/j.1463-6395.2008.00353.x |issn=0001-7272}}</ref> The first members of the [[helicoprionidae]], a family eugeneodonts that were characterized by the presence of one circular tooth whorl in the lower jaw, appeared during the early Carboniferous.<ref>{{cite journal |author1=Cicimurri, D. J. |author2=Fahrenbach, M. D. |year=2002 |title=Chondrichthyes from the upper part of the Minnelusa Formation (Middle Pennsylvanian: Desmoinesian), Meade County, South Dakota |url=http://www.sdaos.org/wp-content/uploads/pdfs/2002/81-92.pdf |journal=Proceedings of the South Dakota Academy of Science |volume=81 |pages=81–92}}</ref> Perhaps the most bizarre radiation of holocephalans at this time was that of the [[iniopterygiformes]], an order of holocephalans that greatly resembled modern day flying fish that could have also "flown" in the water with their massive, elongated pectoral fins. They were further characterized by their large eye sockets, club-like structures on their tails, and spines on the tips of their fins.

<gallery mode="packed">
File:Stethacanthus BW.jpg|''[[Akmonistion]]'' of the [[Holocephali]] order [[Symmoriida]] roamed the oceans of the early Carboniferous.
File:Falcatus.jpg|''[[Falcatus]]'' was a Carboniferous holocephalan, with a high degree of sexual dimorphism.
File:Dracopristis hoffmanorum.png|''[[Dracopristis]]'' was a [[Ctenacanthiformes|Ctenacanthiform]] [[Elasmobranchii|elasmobranch]] from the late Carboniferous of [[New Mexico]].
File:Ornithoprion hertwigi.png|''[[Ornithoprion]]'' was a small-sized [[Eugeneodontida|Eugeneodont]] holocephalan that had an elongated lower jaw.
File:Allenypterus montanus (Restoration) (cropped).jpg|''[[Allenypterus]]'' was a [[Coelacanth]] fish known from the [[Bear Gulch Limestone]] in [[Montana]].
File:†Phanerosteon phonax Carboniferous Bear Gulch.jpg|''[[Phanerosteon]]'' was a [[Osteichthyes|Bony fish]] belonging to the extinct order [[Palaeonisciformes]].
File:Edestus recon.png|''[[Edestus]]'' was a large [[Eugeneodontida|eugeneodontid]] fish that possessed two tooth whorls in its mouth
File:Rhizodus.jpg|''[[Rhizodus]]'' was a large freshwater [[Rhizodontida|Rhizodont]] [[Sarcopterygii|sarcopterygian]] from Europe and North America.
File:Squatinactis NT small.jpg|''[[Squatinactis]]'', a genus of elasmobranch fish from Montana that possessed enlarged pectoral fins similar to modern [[Angelshark|angel sharks]]
File:Bandringa SW.png|''[[Bandringa]]'' is a bizarre elasmobranch fish that lived in [[Illinois]], [[Ohio]] and [[Pennsylvania]] during the [[Moscovian (Carboniferous)|Moscovian]] stage. It superficially resembled a [[paddlefish]], with an elongated upper [[Rostrum (anatomy)|rostrum]].
File:Iniopteryx sp.png|''[[Iniopteryx]]'' was a holocephalan that lived in North America. This fish belonged to a group called the Iniopterygiformes, that possibly lived like [[flying fish]].
File:Strigilodus tollesonae-novataxa 2023-Hodnett Toomey Olson.jpg|Restoration of ''[[Strigilodus tollesonae|Strigilodus]]'', a [[Petalodontiformes|petalodont]] holocephalan from the upper Carboniferous of [[Kentucky]].
</gallery>

===Tetrapods===
Carboniferous [[amphibian]]s were diverse and common by the middle of the period, more so than they are today; some were as long as 6 meters, and those fully terrestrial as adults had scaly skin.{{sfn|Stanley|1999|pp=411–412}} They included basal tetrapod groups classified in early books under the [[Labyrinthodont]]ia. These had a long body, a head covered with bony plates, and generally weak or undeveloped limbs.{{sfn|Howe|1911|p=312}} The largest were over 2 meters long. They were accompanied by an assemblage of smaller amphibians included under the [[Lepospondyli]], often only about {{convert|15|cm|0|abbr=on}} long. Some Carboniferous amphibians were aquatic and lived in rivers (''[[Loxomma]]'', ''[[Eogyrinus]]'', ''[[Proterogyrinus]]''); others may have been semi-aquatic (''[[Ophiderpeton]]'', ''[[Amphibamus]]'', ''[[Hyloplesion]]'') or terrestrial (''[[Dendrerpeton]]'', ''[[Tuditanus]]'', ''[[Anthracosaurus]]'').

The Carboniferous rainforest collapse slowed the evolution of amphibians who could not survive as well in the cooler, drier conditions. Amniotes, however, prospered because of specific key adaptations.{{sfn|Sahney|Benton|Falcon-Lang|2010}} One of the greatest evolutionary innovations of the Carboniferous was the amniote egg, which allowed the laying of eggs in a dry environment, as well as keratinized scales and claws, allowing for the further exploitation of the land by certain [[tetrapod]]s. These included the earliest [[Sauropsida|sauropsid]] reptiles (''[[Hylonomus]]''), and the earliest known [[synapsid]] (''[[Archaeothyris]]''). Synapsids quickly became huge and diversified in the Permian, only for their dominance to stop during the Mesozoic. Sauropsids (reptiles, and also, later, birds) also diversified but remained small until the Mesozoic, during which they dominated the land, as well as the water and sky, only for their dominance to stop during the Cenozoic.

Reptiles underwent a major evolutionary radiation in response to the drier climate that preceded the rainforest collapse.{{sfn|Sahney|Benton|Falcon-Lang|2010}}{{sfn|Kazlev|1998}} By the end of the Carboniferous amniotes had already diversified into a number of groups, including several families of synapsid [[pelycosaur]]s, [[Protorothyrididae|protorothyridids]], [[captorhinidae|captorhinids]], [[sauria]]ns and [[Araeoscelidia|araeoscelid]]s.

<gallery mode="packed">
File:Pederpes2223DB.jpg|The [[amphibian]]-like ''[[Pederpes]]'', the most primitive tetrapod found in the [[Mississippian age|Mississippian]], and known from Scotland.
File:Hylonomus BW.jpg|''[[Hylonomus]]'', the earliest sauropsid [[reptile]], appeared in the [[Pennsylvanian (geology)|Pennsylvanian]], and is known from the [[Joggins Formation]] in Nova Scotia, and possibly [[New Brunswick]].
File:Petrolacosaurus BW.jpg|''[[Petrolacosaurus]]'', the earliest known [[diapsid]] reptile, lived during the late Carboniferous.
File:Archaeothyris BW.jpg|''[[Archaeothyris]]'' is the oldest known [[synapsid]], and is found in rocks from [[Nova Scotia]].
File:Coloraderpeton.jpg|''[[Coloraderpeton]]'' was a [[snake]]-like [[aïstopod]] [[Tetrapodomorpha|tetrapodomorph]] from the late Carboniferous of [[Colorado]].
File:Crassigyrinus BW.jpg|''[[Crassigyrinus]]'' was a carnivorous stem-tetrapod from the [[Viséan|early Carboniferous]] of Scotland.
File:Microbrachis pelikani.png|''[[Microbrachis]]'' was a [[Lepospondyli|lepospondyl]] amphibian known from the [[Czech Republic]].
File:Amphibamus BW.jpg|''[[Amphibamus]]'' was a [[Dissorophoidea|dissorophoid]] [[Temnospondyli|temnospondyl]] from the late Carboniferous of [[Illinois]].
</gallery>

===Fungi===
As plants and animals were growing in size and abundance in this time, land [[fungi]] diversified further. Marine fungi still occupied the oceans. All modern classes of fungi were present in the late Carboniferous.{{sfn|Blackwell|Vilgalys|James|Taylor|2008}}