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Allenypterus montanus was first described by Melton as a Dorypterid; in 1977 this fish was recognized by Lund as a Coelacanth. Taken from "Fossil Fishes of Bear Gulch" by Lund, Richard, and Grogan, E.D., 2005, Bear Gulch web site, www.sju.edu/research/bear_gulch, 1/11/2016 (last update from 2/1/2006): Allenypterus montanus is a coelacanth of relatively primitive skull osteology but with a unique, teardrop-shaped body form. They range in size from about 25 mm (1 inch) to 150 mm (6 1/4 inches) in length. Like other coelacanths, Allenypterus had a complete covering of thin, rounded, overlapping scales, and webbed fins with few, widely spaced rays. No teeth, thick lips, and a very small gape of the mouth show that this fish was a suction feeder on small prey. The body is very high relative to length. The paired fins are large with delicate webbing. The paired fins, second dorsal and anal fins are supported on long muscular lobes by segmental bony axes that are covered with fine rounded scales. There is a long, continuous dorsal lobe of the webbed caudal fin. The combination of all these fins, webs, and lobes indicates a superb maneuverer in weedy, sheltered environments but a fish that could not outswim any predator. It is noteworthy that the belly was armored, suggesting that Allenypterus may have swam and fed on and close to the bottom. The body form of Allenypterus is unique among known coelacanths — all others differ subtly only in proportions. The skull of Allenypterus is among the most primitive coelacanth skulls known. Line drawing from Lund & Lund 1985, p.242: References: Melton, W. G. 1969. A new dorypterid fish from central Montana. Northwest Science 43:196-206 Glickman W. L. 1977: Allenypterus montanus (Crossopterygii: Coelacanthiformes) from the Bear Gulch Limestone of Montana. Adelphy University, 1977. Lund, R. & Lund, W. 1984: New genera and species of coelacanths from the Bear Gulch Limestone (Lower Carboniferous) of Montana (U.S.A.) Geobios, Volume 17, issue 2, p. 237-244. Lund, R., and W.L. Lund, 1985. "Coelacanths from the Bear Gulch Limestone (Namurian) of Montana and the evolution of the Coelacanthiformes." Bull. Carnegie Mus. Nat. Hist. 25: 1-74. Lund, W. L., R. Lund and G. Klein, 1985. "Coelacanth feeding mechanisms and the ecology of the Bear Gulch coelacanths." Compte Rendu, Neuvième Congrès International de Stratigraphie et de Géologie du Carbonifère, 5: 492-500. Friedman, M. & Coates, M. 2006: A newly recognized fossil coelacanth highlights the early morphological diversification of the clade Proc. R. Soc. B (2006) 273, 245–250. Hagadorn, J.: Bear Gulch: An Exceptional Upper Carboniferous Plattenkalk

Taxonomy from Fossilworks.org. Diagnosis for Whiteia woodwardi from Moy-Thomas 1935, p. 215: "Medium sized or small slender Coelacanths. Head relatively large. Skull with triangular operculars and preoperculars, quadrato-jugals, squamosals, postorbitals, lacrimo-jugals, supra- temporals, parietals, five extra scapular (post-parietal) plates and the angular ornamented with numerous tubercles. The coronoids are dumb-bell shaped and unornamented. The dermosphenotics (post frontals) are separate from the frontals, and the supraorbital series are pierced by large lateral line pores. Circumorbital ring well developed. Parasphenoid rather broad. Pterygoids with wide anterior limb and apparantly no notch in their dorsal margin. All the lepidotrichia of the anterior dorsal fin, and at least the most anterior of the dorsal and ventral lobes of the caudal fin ornamented with two rows of denticles. Pelvic fins situated behind the anterior dorsal fin about half-way between the two dorsal fins. Anal fin behind the posterior dorsal fin. Scales ornamented with tubercles, elongated tubercles, short ridges, or ridges stretching the whole length of the exposed area of the scales. This ornament runs approximately antero-posteriorly." References: Moy-Thomas, J. A. (1935) The coelacanth fishes from Madagascar. Geological magazine 72:213-226. Woodward, A.S. (1910) On some Permo-Carboniferous Fishes from Madagascar. Ann. Mag. Natur. Hist., ser. 8, 5: 1-6. Beltan, L. (1980a) Eotrias du Nord-Ouest de Madagascar: Etude de quelques poissons, don’t un est en parturition. Ann Soc. Geol. Nord, 99: 453-464; Lille.

Taxonomy from Fossilworks.com. Diagnosis from Wen et al. 2013, p. 178: "Middle−sized coelacanth. Three diagnostic features are the expanded lachrymojugal, the notched dentary, the large semicircular coronoid, Skull roof has two pairs of parietals. Posterior margin of postparietals embayed. Lachrymojugal has an expanded posterior portion and a concave posteroventral margin. Squamosal has a slightly anterior expansion. Ventral surface of parasphenoid is covered by numerous granular teeth. Dentary has a deeply notched posterior border, and teeth distributed on the separated dentary plate. The first dorsal fin contains 12 robust segmented rays. The lower lobe of the caudal fin is larger than the upper lobe. The following combination of characters, a notched dentary and an expanded lachrymojugal, is not known in any other actinistian, so the Luoping materials must represent a new taxon." Line drawing from Wen et al., p. 183: Identified by oilshale. References: Wen, W. et al. (2013): Coelacanths from the Middle Triassic Luoping Biota, Yunnan, South China, with the earliest evidence of ovoviviparity. Acta Palaeontologica Polonica 58 (1): 175–193. Geng, B., Zhu, M. und Jin, F. (2009): A Revision and Phylogenetic Analysis of Guizhoucoelacanthus (Sarcopterygii, Actinistia) from the Triassic of China. Vertebrata PalAsiatica, 2009, Vol 47, 3, pp. 165-177.

Taxonomy from Fossilworks.org. Diagnosis from Schaumberg 1978, p.195 (translated from German by oilshale): "Medium to large coelacanthid; moderately slender; head one-fifth of total body length. Endocranium partially ossified in anterior part, well ossified in middle part; basisphenoid with strong processus antoticus; no processus basipterygoidus; basal process of basisphenoid distinctly set off; pleurosphenoids present; ossifications on otico-occipital seem to be absent; parasphenoid broadened in its posterior part; separate vomeres not detectable. Posttemporalia and at least 5 extrascapularia developed; parieto-intertemporalia extend to extrascapularia, they are firmly attached to supratemporalia; parieto-intertemporalia not inseparably fused; frontal and dermosphenoticum form uniform bone stiick; both fronto-dermosphenotica not firmly fused; rostro-nasal zone yon numerous, mostly oval bone plates filled (3 pairs of nasalia, several rostralia resp. postrostralia; rearmost closes "fontanella" between nasalia; lateral boundary by stout laterorostralia and elongate tectal plates). Antorbitals absent; postorbitals weakly developed; squamosum and praeoperculum reduced to narrow ossifications around praeopercular sensory canal; small quadrato-jugal above median pterygoid bulge; operculum large and triangular; pterygoid with long, low, anterior limb and broad, vertical limb; maxillary dentition with pointed conical teeth on 6 praemaxillaries, on dermopalatinum and ectopterygoid, there also dental granulation. Large, posterior, nearly triangular coronoid clamped between praearticulate and angular, its exposed part appearing quadrangular; anterior, low coronoid with strong, conical teeth; other, small coronoids presumably between dentary and praearticular, concealed yon tooth-bearing, granulated dentary plates; upper margin of praearticular set with dense denticles; articular with two articulating pits for quadratum and symplecticum; pronounced processus retroarticularis. Gular plates with elongated median apex; urohyals, ceratohyals, hyomandibulars, ceratobranchialia (probably 4 pairs), and symplecticum present. Shoulder girdle composed of clavicle, cleithrum, separate extracleithrum, anocleithrum, supracleithrum; pectoral fin attached slightly below middle of body flank; pelvic girdle composed of narrow bony ridges widened like plates at distal end; ventral fins opposite to space between basal plates of both dorsalia; Basal plate of anterior dorsal fin oval to triangular; basal plate of posterior dorsal fin smaller, with forked projections directed anteriorly, traces of ossification in segmented fin shaft; basal plate of anal fin small and narrow; caudal fin with axial lobes; fin rays of all fins distally clearly articulated. Large, ossified swim bladder between scapular girdle and anal fin, at level of ventral fins is constricted in a muscular manner. Scales large and thin, longer than high; their klelner, exposed part covered with numerous, longitudinally directed tubercles." The diagnosis of the species corresponds to that of the genus. Line drawing from Schaumberg 1978, p. 178: References: L. Agassiz (1843) Recherches Sur Les Poissons Fossiles. Tome I (livr. 18). Imprimerie de Petitpierre, Neuchatel xxxii-188. Schaumberg, G. (1978) Neubeschreibung von Coelacanthus granulatus Agassiz (Actinistia, Pisces) aus dem Kupferschiefer von Richelsdorf (Perm, W.-Deutschland). Paläontol. Z. 52, 169.. https://doi.org/10.1007/BF02987700. H.-P. Schultze (2004) Mesozoic sarcopterygians. Mesozoic Fishes 3 - Systematics, Paleoenvironments and Biodiversity 463-492. C. G. Diedrich (2009) A coelacanthid-rich site at Hasbergen (NW Germany): taphonomy and palaeoenvironment of a first systematic excavation in the Kupferschiefer (Upper Permian, Lopingian). Palaeobiodiversity and Palaeoenvironments 89:67-94.