Annals of the South African MuseumThe Museum, 1991 - Natural history |
From inside the book
Results 1-3 of 19
Page 24
... strongly oblique costae , which may be entire , weakly nodate or strongly tuberculate ; posteroventral shell margin generally crenulated internally . Discussion As here interpreted , the superfamily Megatrigoniacea comprises the famil ...
... strongly oblique costae , which may be entire , weakly nodate or strongly tuberculate ; posteroventral shell margin generally crenulated internally . Discussion As here interpreted , the superfamily Megatrigoniacea comprises the famil ...
Page 29
... strongly produced posteriorly ( H / L = 0,50-0,61 ) . Umbones fairly prominent , rounded , situated about 30 per cent of the shell length from the anterior , with moderately inturned , slightly opisthogyrous beaks . Valves moderately ...
... strongly produced posteriorly ( H / L = 0,50-0,61 ) . Umbones fairly prominent , rounded , situated about 30 per cent of the shell length from the anterior , with moderately inturned , slightly opisthogyrous beaks . Valves moderately ...
Page 33
... strongly inflated anteriorly ( W / H = 0,37-0,43 ) and rostrate posteriorly . The very prominent umbones are subtermi- nal , with strongly inturned , opisthogyrous beaks . The straight , subvertical anterior margin passes evenly into ...
... strongly inflated anteriorly ( W / H = 0,37-0,43 ) and rostrate posteriorly . The very prominent umbones are subtermi- nal , with strongly inturned , opisthogyrous beaks . The straight , subvertical anterior margin passes evenly into ...
Other editions - View all
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