Weyla bodenbenderi (Behrendsen, 1891)
BEHRENDSEN, O. 1891. Zur Geologie des Ostabhanges der argentinischen Cordillere. I Teil. Zeitschrift der Deutschen Geologischen Gesellschaft, 43: 369-420, pls. 22-25. [p. 391, pl. 22, fig. 3]
1891 Pecten bodenbenderi Behrendsen, 1891
1899 Pecten dilatatus R. A. Philippi, 1899
1925 Vola simplex Jaworski, 1925
1899 Pecten dilatatus R. A. Philippi, 1899
1925 Vola simplex Jaworski, 1925
O. Behrendsen, 1891, plate 22.
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«Diese grosse dreieckige, etwa ebenso hohe (ca. 90 mm) wie breite (85 mm) Form mit rechter, hoch gewölbter Klappe, sehr kräftigem, eingekrümmtem Wirbel steht den beiden letzten Arten ziemlich nahe. Die rechte, gewölbte Schale trägt etwa 14 grobe Rippen, von denen die mittleren 9 bis 10 einen rechteckigen Querschnitt besitzen und fast senkrecht in die Zwischenfurchen abfallen. Die letzteren sind flach concav und etwa ebenso breit wie die Rippen. In der Mitte der Furchen erhebt sich eine ziemlich feine Zwischenrippe, die aber auf dem Steinkern selten sichtbar ist. Auf letzterem erscheinen die Rippen schmäler und gerundeter, die Zwischenfurchen flach gewölbt, Die 2 bis 3 Seitenrippen weichen wesentlich von den mittleren ab und bestehen eigentlich aus je einem Paar dicht neben einander liegender, dünner Rippen. Von den Ohren kann nur constatirt werden, dass sie ziemlich klein sind, dass auf ihnen schräg nach unten radiale Rippen verlaufen und dass ausserdem feine Anwachsstreifen, welche dieselben durchkreuzen, bemerkbar sind. — Ueber die linke flache Schale ist wegen mangelnden Materials nichts Zuverlässiges zu berichten.
Fundort: Portezuelo ancho.» OTTO BEHRENDSEN, 1891
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«Description: Weyla (W.) bodenbenderi has a medium-sized, pectiniform, inequivalved shell. The convex right valves carry strong radial ribs, which are broad and rounded and have slightly flattened tops with steep flanks. The interspaces between the ribs are smaller than the ribs or of the same size. In some specimens, fine radial striae are present in these interspaces. In one specimen, the ribs split up before they reach the ventral margin. The flat to slightly convex left valve carries 12 rounded primary ribs, which increase in number by splitting of secondary ribs.
Remarks: These are the first records of the species from Mexico. A much more complete description of W. bodenbenderi was given by Damborenea (1987b) and Aberhan (1994) based on Lower Jurassic specimens from Argentina and Chile, respectively. In Mexico, it occurs together with W. alata at the same localities in the Sierra de Santa Rosa, Sierra del Álamo, and Pozos de Serna, although in much smaller numbers.» SCHOLZ, A., M. ABERHAN & C. M. GONZÁLEZ-LEÓN. 2008. Early Jurassic bivalves of the Antimonio terrane (Sonora, NW Mexico): Taxonomy, biogeography, and paleogeographic implications. Geological Society of America, Special Papers, 442: 269-312, figs. 1-17. [p. 288]
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Weyla (Weyla) bodenbenderi (Behrendsen, 1891); A. Scholz, M. Aberhan & C. M. González-León, 2008, Early Jurassic bivalves of the Antimonio terrane, figure 7K.
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«Affinities: W. bodenbenderi shows strong affinities with W. alata (V. BUCH). Their relations have already been discussed. These two species were never found together and W. bodenbenderi appears always after W alata has disappeared in those localities where both of them occur.
The peculiar ribbing of this species, especially on the left valve, distinguishes it from all other Weyla species, which generally have a more regular and simpler ribbing. The flat-topped ribs on the left valve of W. bodenbenderi are not found in any other known species of Weyla. According to GROEBER (in GROEBER et al. 1953: 233) the specimens that R. PHILIPPI (1899) referred to Pecten dufrenoyi D'ORBlGNY are very similar to W. bodenbenderi. On the other hand JAWORSKI (1914a, 1915) suggested that that material may be referred to W. domeykoi (PHIL.). In fact, the two specimens figured by R. PHILIPPI seem to be internal moulds or weathered shells and thus their specific relations are not evident. The illustration of the left valves of these specimens is surely needed to settle the matter. The specimens from "Neuquen" referred by JAWORSKI (1914a, 1915) to P. domeykoi were not figured. Nevertheless, and according to R. PHILIPPI'S (1899) figures, P. domeykoi differs from W. bodenbenderi by its simple ribs that have neither split nor have intercalated costae and by the more wavy cross-section of the ribbing. Remarks: This species, widely distributed in the early Jurassic beds of Argentina, was originally described by BEHRENDSEN (1891, 1922) based mainly on right valves collected by BODENBENDER at Paso del Portezuelo Ancho, Mendoza province. He only figured one right valve with intercalated ribs. Although LEANZA (1942b: 168) argued that BEHRENDSEN'S drawing does not depict the secondary ribs in their actual position, such a pattern is indeed present in several specimens from various localities, such as Piedra Pintada, Rio de Los Patos, Paso del Portezuelo Ancho and Rio Salado (compare BEHRENDSEN'S Taf. 22, Fig. 3, with pI. 11, fig. 2 here). When the marine lower Jurassic beds of Piedra Pintada were discovered, the Weyla specimens collected there were preliminary determined as "Vola alata" (RoTH 1899: 155; BURCKHARDT 1902; 244-245, pI. 4, fig. 1-2, reproduced by WINDHAUSEN 1931, lam. 22, fig. 2; GROEBER 1925: 463; GROEBER et a1. 1953: 152, 155). In his revision of the South American species of the genus, JAWORSKI (1914a: 285-288, fig. 9-10) provided a detailed description of W. bodenbenderi mainly on the basis of material from that locality. He illustrated one specimen with a very complex ornamentation on the left valve (compare his fig. 10 with pI. 7, fig. 3 here). Nevertheless, his description was based on only four specimens and thus JAWORSKI could not recognize the range of morphological variation of this species. Probably this fact prompted him to consider a left valve from Portezuelo Ancho, characterized by intercalated ribs, as a new species, which he called "Vola simplex" (JAWORSKI 1925a: 163-164, Lám. 1, fig. 1; 1926: 391-392, text-fig. 2, reproduced by WINDHAUSEN 1931). This name is here regarded as a junior synonym of W. bodenbenderi, not only bearing in mind the analysis of the morphological variation of this species, but also upon consideration of a specimen found near Portezuelo Ancho, which has a right valve that is identical to BEHRENDSEN'S original figure of W. bodenbenderi, and a left valve that agrees with JAWORSKI'S (op. cit.) illustration of W. simplex (see pI. 10, fig. 6). It must be noticed as well that BEHRENDSEN did not provide data on the left valve of his species and JAWORSKI did not include any right valve when describing W. simplex. Also both sets of specimens were found at the same locality. The presence of intercalated ribs is a common feature of this species, as the only type of ribbing, or combined with other rib bing patterns. The details of the internal morphology of W. bodenbenderi are first described in this paper and an attempt to analyse the complex variability of ribbing pattern is also made here. Although some of the observed morphotypes seem to be more abundant at certain localities and/or levels, the available material is not enough to attempt a statistical analysis. In the samples with a large number of specimens, such as M 101, from the hill south of Cerro Roth, where they are found in life position, almost all the possible combinations of the ribbing patterns are present and thus the mere record of one or other morphotype lacks any stratigraphical, palaeobiogeographical or palaeoecological significance.» DAMBORENEA, S. E. 1987. Early Jurassic Bivalvia of Argentina; Part 2, Superfamilies Pteriacea, Buchiacea and part of Pectinacea. Palaeontographica, Abteilung, A, Palaeozoologie-Stratigraphie, 199 (4-6): 113-216, pls. 1-14. [p. 183, 184]
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Weyla (Weyla) bodenbenderi (Behrendsen, 1891); S. E. Damborenea, 1987, Early Jurassic Bivalvia of Argentina, Part 2, Superfamilies Pteriacea, Buchiacea and part of Pectinacea, plate 7, figure 3; plate 10, figure 6; plate 11, figures 1, 2; plate 12, figures 1-3.
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«Supplementary Description. Shell very large, right valve strongly convex, and a little higher than long. The right valve is strongly arched, the beak incurved so as to project over and past the left valve, and the umbonal angle averages 70°. The upper, anterior and posterior ends of the valve are rounded and extend slightly inward toward the center of the shell. A narrow and rather deep groove is developed at either end of the valve along the junctions with the anterior and posterior ears. The surface of the valve is ornamented with very fine, closely spaced growth striae, which are crossed with 13 or 14 prominently raised, broad, round-topped radiating ribs with interspaces only two-thirds as wide. The slopes of the sides of the 7 middle ribs are almost vertical, but those on-the anterior and posterior ends of the shell, especially away from the umbones, are much less. The surfaces of the interspaces are nearly flat to very slightly concave and contain in the middle a single, minor, radiating rib about one-third as wide as the interspace. In addition there sometimes occurs a third set of smaller ribs on the sides of the major ribs just above their junction with the interspaces. These are especially developed on the three anterior and posterior major ribs, and toward the base become so prominent as to equal in size the major ribs themselves and to appear as bifurcations of them. Where the growth striae cross the major ribs they are convex upwards, but the reverse is true on the interspaces.
The left valves are usually missing on most of the specimens of this species, but the molds indicate 12 radiating ribs with interspaces of triple width. On the anterior half of the valve these ribs begin to bifurcate, and near the lower margin are of equal strength with interspaces of equal width. Dimensions. Length, 120 mm; height, 130 mm; apical angle, 72°. Remarks. This species is characterized by the strong convexity of the right valve, the heavy, broad, round topped, radiating ribs with narrower interspaces, and the occurrence of a single well developed minor rib in the middle of each of these. The tertiary ribs developed on the sides of the major ribs on the anterior and posterior ends of the shell, and their prominence as they approach the basal border are all characteristic and serve to distinguish the species readily from others occurring with it. Occurrence. This species occurs at locality 1029 in the middle Lias of Southern Neuquen near Piedra Pintada. Type Material. Plesiotype. No. 166.» WEAVER, C. E. 1931. Paleontology of the Jurassic and Cretaceous of West Central Argentina. Memoirs of the University of Washington, 1: 1-469, pls. 1-62. [p. 283, 284]
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Vola bodenbenderi Behrendsen; C. E. Weaver, 1931, Paleontology of the Jurassic and Cretaceous of West Central Argentina, plate 33, figure 184.
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