Pectoral Morphology in Doliodus: Bridging the ‘Acanthodian’-Chondrichthyan Divide

@article{Maisey2017PectoralMI,
  title={Pectoral Morphology in Doliodus: Bridging the ‘Acanthodian’-Chondrichthyan Divide},
  author={John G. Maisey and Randall F. Miller and Alan Pradel and John S. S. Denton and Allison W. Bronson and Philippe Janvier},
  journal={American Museum Novitates},
  year={2017},
  pages={1 - 15}
}
ABSTRACT Doliodus problematicus (NBMG 10127), from the Lower Devonian of New Brunswick, Canada (approx. 397–400 Mya) is the earliest sharklike jawed vertebrate (gnathostome) in which the pectoral girdle and fins are well preserved. Its pectoral endoskeleton included sharklike expanded paired coracoids, but Doliodus also possessed an “acanthodian-like” array of dermal spines, described here for the first time. Doliodus provides the strongest anatomical evidence to date that chondrichthyans arose… Expand
A revision of Vernicomacanthus Miles with comments on the characters of stem‐group chondrichthyans
TLDR
Anatomic similarities between Vernicomacanthus and gyracanths may indicate the existence of a grade including these and similar acanthodian-grade taxa placed relatively crownwards in the chondrichthyan stem-group. Expand
Morphology and histology of acanthodian fin spines from the late Silurian Ramsasa E locality, Skane, Sweden
TLDR
The results support the current hypothesis of gnathostome phylogeny, which places "acanthodians" on the chondrichthyan stem and emphasize the need for further study of vertebrate fin spines using 3D approaches. Expand
Spines of the stem chondrichthyan Doliodus latispinosus (Whiteaves) comb. nov. from the Lower Devonian of eastern Canada
The higher taxonomic affinities of fin spines from the Lower Devonian (Emsian) Atholville beds, Campbellton Formation, near Campbellton, New Brunswick, Canada, originally identified as CtenacanthusExpand
A symmoriiform from the Late Devonian of Morocco demonstrates a derived jaw function in ancient chondrichthyans
TLDR
A previously undescribed symmoriiform shark, Ferromirum oukherbouchi, from the Late Devonian of the Anti-Atlas is reported, in which the jaw articulation is specialized and drives mandibular rotation outward when the mouth opens, and inward upon closure. Expand
An early chondrichthyan and the evolutionary assembly of a shark body plan
TLDR
Preliminary phylogenetic results highlight the likely convergent evolution of conventional chondrichthyan conditions among earliest members of this primary gnathostome division, while skeletal morphology points towards the likely suspension feeding habits of Gladbachus, suggesting a functional origin of the gill slit condition characteristic of the vast majority of living and fossil chondRichthyans. Expand
A new stem sarcopterygian illuminates patterns of character evolution in early bony fishes
TLDR
A new lobe-finned fish Ptyctolepis brachynotus dating from the Early Devonian is described, which preserves a novel combination of cranial characters and suggests revision of evolutionary relationships among bony fish. Expand
Early Silurian chondrichthyans from the Tarim Basin (Xinjiang, China)
TLDR
The results corroborate previous work by recognising lamellin as the main component of sinacanthid spines and point to corresponding developmental patterns shared across the dermal skeleton of taxa with lameLLin and more derived chondrichthyans (e.g. in Seretolepis, Parexus). Expand
Vascularization and odontode structure of a dorsal ridge spine of Romundina stellina Ørvig 1975
TLDR
Detailed descriptions of the microstructure and growth of a dorsal ridge spine from the acanthothoracid placoderm, Romundina stellina, are provided using virtual three-dimensional paleohistological datasets and indicate that the spine grew differently from the dentinous fin spines from extant and fossil chondrichthyans. Expand
3D imaging of shark egg cases (Palaeoxyris) from Sweden with new insights into Early Jurassic shark ecology
ABSTRACT Several shark species produce egg cases as protective casings in which their embryos develop. These casings are composed of multiple layers of collagen and are extremely durable, making themExpand
Freshwater fish faunas from two Permian rift valleys of Zambia, novel additions to the ichthyofauna of southern Pangea
Abstract Toward the end of the Paleozoic , Earth's land masses formed the supercontinent Pangea . Despite the relative lack of large-scale physical dispersal barriers, patterns of endemism andExpand
...
1
2
3
...

References

SHOWING 1-10 OF 25 REFERENCES
Osteichthyan-like cranial conditions in an Early Devonian stem gnathostome
TLDR
A conjunction of well-developed cranial processes in Janusiscus helps unify the comparative anatomy of early jawed vertebrate neurocrania, clarifying primary homologies in ‘placoderms’, osteichthyans and chondrichthyans. Expand
A re-examination of Lupopsyrus pygmaeus Bernacsek & Dineley, 1977 (Pisces, Acanthodii)
TLDR
New anatomical details are described for the acanthodian Lupopsyrus pygmaeus based on newly prepared, nearly complete body fossils from the MOTH locality, Northwest Territories, Canada, and it is suggested that there is no evidence allying L. pygMAeus to the traditional “climatiid” Acanthodians contrary to previous historical classifications. Expand
A Silurian placoderm with osteichthyan-like marginal jaw bones
TLDR
A three-dimensionally preserved 419-million-year-old placoderm fish from the Silurian of China is described that represents the first stem gnathostome with dermal marginal jaw bones (premaxilla, maxilla and dentary), features previously restricted to Osteichthyes. Expand
The braincase of the chondrichthyan Doliodus from the Lower Devonian Campbellton Formation of New Brunswick, Canada
TLDR
Doliodus has curious bar-like, paired subcranial ridges ending posteriorly at the hyomandibular articulation, adding circumstantial palaeontological support to the old proposal that parts of visceral arches may be incorporated into the gnathostome braincase, although it seems more plausible that they formed in the lateral margins of the embryonic parachordal or hypotic lamina. Expand
Revision of Climatius reticulatus Agassiz, 1844 (Acanthodii, Climatiidae), from the Lower Devonian of Scotland, Based on New Histological and Morphological Data
ABSTRACT Disarticulated elements in a large, uncompressed regurgitate from Tillywhandland Quarry (Lochkovian), as well as serial sections of an articulated specimen, reveal the three-dimensionalExpand
The braincase and jaws of a Devonian ‘acanthodian’ and modern gnathostome origins
TLDR
The first-known braincase of an Early Devonian acanthodian is presented, andylogenetic analysis resolves Ptomacanthus as either the most basal chondrichthyan or as the sister group of all living gnathostomes, to provide a more detailed picture of the acquisition of early Gnathostome characters. Expand
The evolution of paired fins
  • M. Coates
  • Computer Science
  • Theory in Biosciences
  • 2003
TLDR
The Archipterygium is Gegenbaur’s most lasting contribution to the study of vertebrate limb evolution, and an iterative homology between scapulocoracoid and extrabranchial cartilages is suggested. Expand
The oldest articulated chondrichthyan from the Early Devonian period
TLDR
This specimen is the oldest shark showing the tooth families in situ, and preserves one of the oldest chondrichthyan braincases, and shows the presence of paired pectoral fin-spines, previously unknown in cartilaginous fishes. Expand
The diplacanthid fishes (Acanthodii, Diplacanthiformes, Diplacanthidae) from the Middle Devonian of Scotlan
The Diplacanthiformes are a clade of acanthodian fishes which were widespread during the Middle and early Late Devonian. They are best represented in the Middle Devonian, by articulated fossils, finExpand
Dental patterning in the earliest sharks: Implications for tooth evolution
TLDR
Doliodus provides several clues about the early evolution of the “shark‐like” dentition in chondrichthyans and also raises new questions about the evolution of oral teeth in jawed vertebrates. Expand
...
1
2
3
...