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Showing results for tags 'pteronisculus'.
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First of all, the list of fish found in Madagascar - there are more than 30 species! So many that I can't treat all of them (and I've never seen some of them). There is relatively old, but good literature on it - Lehman has written one of the most comprehensive publications on this subject: J.-P.Lehman (1952) Etude Complementaire des Poisson de L'Eotrias de Madagascar. Kungl. Svenska Vetenskapsakademiens Handlingar. Fjärde Serien Bd 2 No 6 (in French, 244 pages, 340MB!) Australosomus merlei Piveteau, 1934 is easy to recognize: Small to medium size fish (~ 10 to 15cm / 4 to 6"), fusiform body, relatively small head with a slightly rounded snout. Its dorsal fin is located in the posterior fourth of the body. Caudal fin divided with wide lobes. Scales on the flanks are noticeably stalk-shaped. Ecrinesomus dixoni Woodward, 1910 Medium sized fish with a rounded, laterally flattened body. Snout flattened. Dorsal and anal fins opposite and broad based. Attached behind the body's midpoint. Rhombic body. Caudal fin large, deeply divided. Often mixed up with the somehow similar looking Bobasatrania mahavavica. Unfortunately the head is not completely preserved. Bobasatrania mahavavica White, 1932 There's quite a confusion between Ecrinesomus and Bobasatrania. Even in publications the same reconstruction (the same drawing!) is sometimes labeled as Bobasatrania and sometimes as Ecrinesomus. In the first publication about Ecrinesomus, one Bobasatrania was mistakenly mixed in between. Bobasatrania has a crooked diamond-shaped body – while Ecrinesomus's anal and dorsal fins start directly opposite. Boreosomus gillioti Priem, 1924 Small to medium sized fish (10 to 20 cm / 4 to 8"). Slender body, dorsal fin small, located before the body's midpoint. Caudal fin divided. Strong, rectangular scales. Parasemionotus labordei Priem, 1924 Small fish (up to 15cm / 6") with a rounded body, somewhat thickset appearance. Broad but short head. Dorsal fin attached to the posterior half of the body. Pectoral and anal fins small. Caudal fin moderately divided. Eyes remarkably large. Teffichthys madagascariensis Piveteau, 1934 (=Perleidus madagascariensis) Medium sized fish with a somewhat thickset appearance. Bulky head. Its dorsal fin is located in the posterior third of the body. Pteronisculus cicatrosus White, 1934 Small to medium fish with fusiform body (less than 15cm / 6" ?). Small dorsal fin, located slightly behind the midpoint of the body, diagonally opposite the anal fin. Big eyes. Relatively long and broad pectoral fins. Comparatively small scales. Pteronisculus macropterus White, 1933 In his 1933 paper, White described two new Pteroniscoids from Madagascar: Pteronisculus cicatrosus , which is rather common and the somewhat rarer Pteronisculus macropterus. According to White, P. macropterus is characterized by an "elongate-fusiform body; maximum depth rather less than length of head with opercular apparatus, and equal to one-quarter total length to base of caudal fin. length of pectoral fin exceeding distance between tip of snout and hinder margin of maxilla. Origin of dorsal fin above fortieth scale-row from pectoral girdle approximately. Scales in more than seventy vertical rows to base of caudal fin, and ornamented with oblique rugae only." Paracentrophorus madagascariensis Piveteau, 1940 Small fish (up to 15cm / 6") with a rounded body, somewhat thickset appearance. Dorsal fin attached to the posterior half of the body. Pectoral and anal fin relatively large. Anal fin starts well behind end of dorsal fin. Caudal fin moderately divided. Eyes remarkably large. Icarealcyon malagasium Beltan, 1984 Icarealcyon can be easily mixed up with Parasemionotus; characteristic are the huge pectoral fins. Due to its enormous pectoral fins, Icarealcyon malagasium was described by Beltan as a "poisson volant" - a "flying fish" - in the family Semonotidae (not related to what is now known as "flying fish" - these are Exocoetidae in the order Beloniformes). You would expect flying fish to be fast swimmers - the rather thickset appearance of Icarealcyon more likely hints to slow swimmers with relatively high maneuverability (comparable to Albertonia from British Columbia). Fig. C is Icarealcyon - the reconstruction is not quite correct. Saurichthys madagascariensis Piveteau, 1945 Medium sized fish with elongated, streamlined jaws. Head elongated. Dorsal fin almost at the end of the body, opposite the anal fin. Small scales. Whiteia woodwardi Moy-Thomas, 1935 Massive body. Pectoral fin attached slightly before the first dorsal fin. Piveteauia madagascariensis Lehman 1952 More slender body. Pectoral fin attached well before first dorsal fin lobe. Ventral fin opposite to first dorsal fin lobe. Have fun Thomas PS: If you are interested in Lehman's paper send me a PM with your email address (remember - 340MB!)
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Hello, Is this fish fossil real? Listed as Pteronisculus from Madagascar, length 12cm. Any apparent reconstruction or fabrication? And how complete is it? Looks like the tip of the head may be cut off. Thanks.
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From the album: Vertebrates
Pteronisculus macropterus White, 1933 Early Triassic Sakamena formation Ambilobe Madagascar Length 28cm-
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In his 1933 paper, White described two new Pteroniscoids from Madagascar: Pteronisculus cicatrosus , which is rather common and the somewhat rarer Pteronisculus macropterus. Diagnosis from White 1933, p. 126: "Pteronisculus with elongate-fusiform body; maximum depth rather less than length of head with opercular apparatus, and equal to one—quarter total length to base of caudal fin. Length of pectoral fin exceeding distance between tip of snout and hinder margin of maxilla. Origin of dorsal fin above fortieth scale—row from pectoral girdle approximately. Scales in more than seventy vertical rows to base of caudal fin, and ornamented with oblique rugæ only." Sketch from White 1933, p. 126: References: White, E. I. (1933): New Triassic palaeoniscids from Madagascar. Ann. a. Mag. Nat. Hist.(10) 11: 118-128; London
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From the album: Vertebrates
Pteronisculus macropterus White, 1933 Lower Triassic Dienerian Ambodipo Madagascar Length 8cm / 3"-
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Taxonomy from Lehman 1952. Genus Diagnosis from White 1933, p. 118: "Palæoniscidæ with fusiform bodies, long heads, and large orbits anteriorly placed. Gape wide and suspensorium very oblique. Frontals long with extreme irregular media] and digitate parietal sutures; parietals well developed with short triradiate sensory grooves and produced forwards into conspicuous median “ processes.” Preoperculum bent almost at fight-angles, with upper horizontal limb long and roughly triangular, but truncated by supratemporal margin: long wedge shaped bone “ Y ” in excavated antero—superior margin of operculum. Supratemporal large with anterior arm dividing strap-like intertemporal from frontal; four or five postorbital bones present. Teeth on outer margins of maxilla and dentary numerous, minute and sharply pointed. Fin—raye fine and very numerous, articulated dîstally in pectorals, but throughout in other fins; all distanty dichotomized; fulcra minute. Pectoral fins large, their length exceeding distance between their origin and that of ventralfins, which is somewhat nearer pectoral than anal fins; ventral and unpaired fins well developed, the triangular dorsal being posteriorly placed and somewhat anterior in position to similarly—shaped anal. Posterior half of caudal fin unknown. Scales small and numerous, deeplÿ overlapping, rhomboid in shape, their exposed surfaces covered with ganoine, obliquely ridged, and denticulated posteriorly." Species Diagnosis from White 1933, p. 120: "A Pteronisculus with fusiform body; maximum depth about equal to length of head with opercular apparatus, and rather less than one—third of total length to base of caudal fin. Length of pectoral fin somewhat less than distance between tip of snout and hinder margin of maxilla. Origin of dorsal fin above thirty—fourth scale—row from pectoral girdle approximately. Scales in about fifty—five vertical rows to base of caudal fin, and ornamented with oblique rugæ and a few finer rugæ running parallel to lower margin of scale on main flank—scales." Line drawing of the head from White 1933, p. 119: Line drawing from Lehman 1952, p. 69. References: White E. I. (1933) New Triassic Palaeoniscids from Madagascar. The Annals and Magazine of Natural History, Tenth Series 10:118-128. Lehman. J.-P. (1952) Etude complémentaire des poissons de l'Eotrias de Madagascar. Kungliga Svenska Vetenskapsakademiens Handlingar 2:1-201.
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Taxonomy from Lehman 1952. Genus Diagnosis from White 1933, p. 118: "Palæoniscidæ with fusiform bodies, long heads, and large orbits anteriorly placed. Gape wide and suspensorium very oblique. Frontals long with extreme irregular media] and digitate parietal sutures; parietals well developed with short triradiate sensory grooves and produced forwards into conspicuous median “ processes.” Preoperculum bent almost at fight-angles, with upper horizontal limb long and roughly triangular, but truncated by supratemporal margin: long wedge shaped bone “ Y ” in excavated antero—superior margin of operculum. Supratemporal large with anterior arm dividing strap-like intertemporal from frontal; four or five postorbital bones present. Teeth on outer margins of maxilla and dentary numerous, minute and sharply pointed. Fin—raye fine and very numerous, articulated dîstally in pectorals, but throughout in other fins; all distanty dichotomized; fulcra minute. Pectoral fins large, their length exceeding distance between their origin and that of ventralfins, which is somewhat nearer pectoral than anal fins; ventral and unpaired fins well developed, the triangular dorsal being posteriorly placed and somewhat anterior in position to similarly—shaped anal. Posterior half of caudal fin unknown. Scales small and numerous, deeplÿ overlapping, rhomboid in shape, their exposed surfaces covered with ganoine, obliquely ridged, and denticulated posteriorly." Species Diagnosis from White 1933, p. 120: "A Pteronisculus with fusiform body; maximum depth about equal to length of head with opercular apparatus, and rather less than one—third of total length to base of caudal fin. Length of pectoral fin somewhat less than distance between tip of snout and hinder margin of maxilla. Origin of dorsal fin above thirty—fourth scale—row from pectoral girdle approximately. Scales in about fifty—five vertical rows to base of caudal fin, and ornamented with oblique rugæ and a few finer rugæ running parallel to lower margin of scale on main flank—scales." Line drawing of the head from White 1933, p. 119: Line drawing from Lehman 1952, p. 69. References: White E. I. (1933) New Triassic Palaeoniscids from Madagascar. The Annals and Magazine of Natural History, Tenth Series 10:118-128. Lehman. J.-P. (1952) Etude complémentaire des poissons de l'Eotrias de Madagascar. Kungliga Svenska Vetenskapsakademiens Handlingar 2:1-201. References: White, E. I. (1933): New Triassic palaeoniscids from Madagascar. Ann. a. Mag. Nat. Hist.(10) 11: 118-128; London.
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