Annals of the South African MuseumThe Museum, 1991 - Natural history |
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Page 25
... finely crenulated and often crowded costellae , inner margin of shell crenulated posteroventrally ; 4 : = escutcheon with transverse costellae ; 5 = posteriorly produced to rostrate , often inflated anteriorly , in some with subterminal ...
... finely crenulated and often crowded costellae , inner margin of shell crenulated posteroventrally ; 4 : = escutcheon with transverse costellae ; 5 = posteriorly produced to rostrate , often inflated anteriorly , in some with subterminal ...
Page 33
... finely beaded , transverse costellae that are narrower than the interspaces . The area is narrow , unornamented beyond the nepionic stages and has a persistent longitudinal groove . As in P. tocaimaana ( Lea ) , there is a prominent ...
... finely beaded , transverse costellae that are narrower than the interspaces . The area is narrow , unornamented beyond the nepionic stages and has a persistent longitudinal groove . As in P. tocaimaana ( Lea ) , there is a prominent ...
Page 39
... finely crenulated costella . It is with final loss of coarse tuberculation that the change to the posterior set occurs in which the wavy , crowded , subvertical costellae are finely crenulated throughout . There are about 10-12 costae ...
... finely crenulated costella . It is with final loss of coarse tuberculation that the change to the posterior set occurs in which the wavy , crowded , subvertical costellae are finely crenulated throughout . There are about 10-12 costae ...
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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