A New Species of <i>Megalichthys</i> (Sarcopterygii, Megalichthyidae) from the Upper Devonian (Famennian) of Pennsylvania, U.S.A., and a Report on the Cosmine-Covered Osteolepiform Fossils of the Catskill Formation

Downs, Jason P.; Daeschler, Edward B.

doi:10.1080/02724634.2020.1774771

Cited by 5 publications

(11 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To the original matrix we included five megalichthyids or taxa assigned to be likely megalichthyids: Sengoerichthys ottoman ( Janvier, Clément & Cloutier, 2007 ), Palatinichthys laticeps ( Witzmann & Schoch, 2012 ), Askerichthys heintzi ( Borgen & Nakrem, 2016 ), Mahalalepis resima ( Young, Long & Ritchie, 1992 ), and Megalichthys mullisoni ( Downs & Daeschler, 2020 ). In addition, we recoded Cladarosymblema based on our new morphological description presented herein, with additional codings for Mahalalepis based on work currently in preparation (J Lu, 2021, pers.…”

Section: Methodsmentioning

confidence: 99%

“…This contrasts with Palatinichthys laticeps which has three submandibulars ( Witzmann & Schoch, 2012 ), and A. heintzi which has six ( Borgen & Nakrem, 2016 ). There is an area for overlap with the subopercular on the last (posterior-most) submandibular only, in contrast to M. mullisoni which is said to have contact between the subopercular and the second [last] submandibular ( Downs & Daeschler, 2020 ). There is no evidence of a groove on the underside of the operculum as seen on QMF21105 ( Fox et al, 1995 ).…”

Section: Descriptionmentioning

confidence: 99%

“…More specifically, Hay (1902) was the first to coin the term “Megalichthyidae”, after which Long (1985) suggested synapomorphies to define this particular “osteolepidid” clade, but the first full familial description was not provided until Young, Long & Ritchie (1992) . This was later revised by Fox et al (1995) , Borgen & Nakrem (2016) , and again most recently by Downs & Daeschler (2020) .…”

Section: Introductionmentioning

confidence: 98%

“…In describing a new species of Megalichthys ( M. mullisoni ) from the Famennian of USA, Downs & Daeschler (2020) reduced the characters defining the family to three specialised features: (premaxillary tusk that interrupts or lies lingual to the premaxillary marginal tooth row; contact between the subopercular and second [posterior-most] submandibular; and a distinct supratemporal bone), in combination with one plesiomorphic character (cosmine cover on dermal bones).…”

Section: Introductionmentioning

confidence: 99%

“…Aside from Cladarosymblema , there are several other genera commonly recognised within the Megalichthyidae: Megalichthys ( Agassiz, 1835 ) contains several species found in Devonian-Carboniferous deposits across North America ( Cope, 1882 ; Downs & Daeschler, 2020 ), Morocco ( Janvier & Martin, 1979 ), and the UK ( Thomson, 1964 ); Ectosteorhachis nitidus ( Cope, 1882 ) is known from the Lower Permian of the USA ( Thomson, 1964 ); Sengoerichthys ottoman —considered by some as the earliest megalichthyid—from the Frasnian of Turkey ( Janvier, Clément & Cloutier, 2007 ); Palatinichthys laticeps described from the Lower Permian of Germany ( Witzmann & Schoch, 2012 ); and the most recently described megalichthyid genus, Askerichthys heintzi, comes from the Late Carboniferous of Norway ( Borgen & Nakrem, 2016 ). However, Downs & Daeschler (2020) considered that the “unusual combinations of characters” in S. ottoman and P. laticeps precluded them from being megalichthyids.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

A fresh look at Cladarosymblema narrienense, a tetrapodomorph fish (Sarcopterygii: Megalichthyidae) from the Carboniferous of Australia, illuminated via X-ray tomography

Clement

Cloutier

Lü

et al. 2021

PeerJ

View full text Add to dashboard Cite

Background The megalichthyids are one of several clades of extinct tetrapodomorph fish that lived throughout the Devonian–Permian periods. They are advanced “osteolepidid-grade” fishes that lived in freshwater swamp and lake environments, with some taxa growing to very large sizes. They bear cosmine-covered bones and a large premaxillary tusk that lies lingually to a row of small teeth. Diagnosis of the family remains controversial with various authors revising it several times in recent works. There are fewer than 10 genera known globally, and only one member definitively identified from Gondwana. Cladarosymblema narrienense Fox et al. 1995 was described from the Lower Carboniferous Raymond Formation in Queensland, Australia, on the basis of several well-preserved specimens. Despite this detailed work, several aspects of its anatomy remain undescribed. Methods Two especially well-preserved 3D fossils of Cladarosymblema narrienense, including the holotype specimen, are scanned using synchrotron or micro-computed tomography (µCT), and 3D modelled using specialist segmentation and visualisation software. New anatomical detail, in particular internal anatomy, is revealed for the first time in this taxon. A novel phylogenetic matrix, adapted from other recent work on tetrapodomorphs, is used to clarify the interrelationships of the megalichthyids and confirm the phylogenetic position of C. narrienense. Results Never before seen morphological details of the palate, hyoid arch, basibranchial skeleton, pectoral girdle and axial skeleton are revealed and described. Several additional features are confirmed or updated from the original description. Moreover, the first full, virtual cranial endocast of any tetrapodomorph fish is presented and described, giving insight into the early neural adaptations in this group. Phylogenetic analysis confirms the monophyly of the Megalichthyidae with seven genera included (Askerichthys, Cladarosymblema, Ectosteorhachis, Mahalalepis, Megalichthys, Palatinichthys, and Sengoerichthys). The position of the megalichthyids as sister group to canowindrids, crownward of “osteolepidids” (e.g.,Osteolepis and Gogonasus), but below “tristichopterids” such as Eusthenopteron is confirmed, but our findings suggest further work is required to resolve megalichthyid interrelationships.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Descriptionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A fresh look at Cladarosymblema narrienense, a tetrapodomorph fish (Sarcopterygii: Megalichthyidae) from the Carboniferous of Australia, illuminated via X-ray tomography

Clement

Cloutier

Lü

et al. 2021

PeerJ

View full text Add to dashboard Cite

show abstract

A new species of Eusthenodon (Sarcopterygii, Tristichopteridae) from the Upper Devonian (Famennian) of Pennsylvania, U.S.A., and a review of Eusthenodon taxonomy

Downs

Barbosa

Daeschler

2021

Journal of Vertebrate Paleontology

View full text Add to dashboard Cite

Fitting fangs in a finite face: A novel fang accommodation strategy in a 280‐million‐year‐old ray‐finned fish

Figueroa

Andrews

2022

Journal of Anatomy

View full text Add to dashboard Cite

Though Paleozoic ray‐finned fishes are considered to be morphologically conservative, we report a novel mode of fang accommodation (i.e., the fitting of fangs inside the jaw) in the Permian actinopterygian † Brazilichthys macrognathus , whereby the teeth of the lower jaw insert into fenestrae of the upper jaw. To better understand how fishes have accommodated lower jaw fangs through geologic time, we synthesize the multitude of ways living and extinct osteichthyans have housed large mandibular dentition. While the precise structure of fang accommodation seen in † Brazilichthys has not been reported in any other osteichthyans, alternate strategies of upper jaw fenestration to fit mandibular fangs are present in some extant ray‐finned fishes—the needlejaws Acestrorhynchus and the gars of the genus Lepisosteus . Notably, out of our survey, only the two aforementioned neopterygians bear upper jaw fenestration for the accommodation of mandibular fangs. We implicate the kinetic jaws of neopterygians in this trend, whereby large mandibular fangs are more easily fit between the multitude of upper jaw and palatal bones. The restricted space available in early osteichthyan jaws may have led to a proliferation of novel ways to accommodate large dentition. We recommend a greater survey of Paleozoic actinopterygian jaw morphology, in light of these results and other recent reevaluations of jaw structure in early fossil ray‐fins.

show abstract

A New Species of Megalichthys (Sarcopterygii, Megalichthyidae) from the Upper Devonian (Famennian) of Pennsylvania, U.S.A., and a Report on the Cosmine-Covered Osteolepiform Fossils of the Catskill Formation

Cited by 5 publications

References 31 publications

A fresh look at Cladarosymblema narrienense, a tetrapodomorph fish (Sarcopterygii: Megalichthyidae) from the Carboniferous of Australia, illuminated via X-ray tomography

A fresh look at Cladarosymblema narrienense, a tetrapodomorph fish (Sarcopterygii: Megalichthyidae) from the Carboniferous of Australia, illuminated via X-ray tomography

A new species of Eusthenodon (Sarcopterygii, Tristichopteridae) from the Upper Devonian (Famennian) of Pennsylvania, U.S.A., and a review of Eusthenodon taxonomy

Fitting fangs in a finite face: A novel fang accommodation strategy in a 280‐million‐year‐old ray‐finned fish

Contact Info

Product

Resources

About