Annals of the South African MuseumThe Museum, 1991 - Natural history |
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Page 24
... straight rows directed posteroventrally over much of the shell surface . Anteriorly the tubercle rows are narrower than the interspaces but posteriorly they are as wide as , or slightly wider than , the interspaces . There may be some ...
... straight rows directed posteroventrally over much of the shell surface . Anteriorly the tubercle rows are narrower than the interspaces but posteriorly they are as wide as , or slightly wider than , the interspaces . There may be some ...
Page 33
... straight , subvertical anterior margin passes evenly into the almost straight ventral margin . The posterodorsal margin is broadly concave and the respiratory margin seems to have been narrowly rounded . The oval , flattened anterior ...
... straight , subvertical anterior margin passes evenly into the almost straight ventral margin . The posterodorsal margin is broadly concave and the respiratory margin seems to have been narrowly rounded . The oval , flattened anterior ...
Page 39
... straight , very high , with broad , flattish anterior face , passing rather sharply into the broad , straight to slightly concave ventral margin . The posterodorsal margin is deeply concave and the narrow respiratory margin rounded ...
... straight , very high , with broad , flattish anterior face , passing rather sharply into the broad , straight to slightly concave ventral margin . The posterodorsal margin is deeply concave and the narrow respiratory margin rounded ...
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Common terms and phrases
Algoa Basin Anditrigonia antecarinal sulcus anterior commissure anterolateral shoulder anteroventrally Apiotrigoniinae Bivalvia broad chevrons coarse commissure comprises convex Cooper Cretaceous Description Shell Diagnosis elongate escutcheon carina faunas finely crenulated flank costae flank ornament genus growth rugae growth striae Hauterivian Hoepen holotype inflated anteriorly interspaces Iotrigonia irregular Kobayashi kraussi Kitchin lanceolate large maximum length Lateral view lectotype left valve longitudinal groove Megatrigoniacea moderately Myophorella Myophoriidae Nakano neotype nepionic stages Neumayr nodate Nototrigoniinae opisthogyrous beaks Paranditrigonia paratypes persisting to maturity phyletic Port Elizabeth Museum posterior set posterodorsal margin Poulton Pterotrigonia radial costellae radial ornament Rennie respiratory margin Reyes ribs right valve rostrate shallowly concave shell length Skwarko smooth South African Museum Steinmanella herzogi Goldfuss straight strongly oblique subconcentric subfamily Sundays River Superfamily synonymy Tashiro Tithonian transverse costellae transverse ornament Trigonia Trigoniacea Trigoniinae trigonioid tubercles Type species Upper Valanginian V-shaped Valanginian vau Sharpe ventral margin ventricosa Krauss Yaadia