The illustrations of Salpingacantha species from Kofoid & Campbell

The illustrations of Salpingacantha species from Kofoid & Campbell 1929 arranged as the evolutionary series given in Kofoid & Campbell 1939 in which S. perca "presents the earliest phase in evolution of toothed oral margin": a. S. perca, b. S. crenulata, c. S. exilis, d. S. simplex, e. S. unguiculata, f. S. ampla, and g. S. undata. Note that S. perca, S. exilis, and S. unguiculata are depicted with a diaphragm apparatus similar to those of Salpingella (Agatha 2010).