Skip to content Skip to navigation

Article: Fortipecten takahashii, a reclining pectinid from the Pliocene of north Japan

Publication: Palaeontology
Volume: 31
Part: 2
Publication Date: May 1988
Page(s): 419 444
Author(s): Itaru Hayami and Ichiro Hosoda
Addition Information

How to Cite

HAYAMI, I., HOSODA, I. 1988. Fortipecten takahashii, a reclining pectinid from the Pliocene of north Japan. Palaeontology31, 2, 419–444.

Online Version Hosted By

The Palaeontological Association (Free Access)


The adaptive morphology and mode of life of a large bizarre pectinid, Fortipecten takahashii (Yokoyama) from the Pliocene of north Japan and Sakhalin, were examined mainly from the standpoint of relative growth. In spite of its similarity to some extant species of Patinopecten in the early growth stage, Gryphaea-like and unusually heavy valves are formed after the middle stage by a drastic change of growth pattern. In the later stage, unlike many swimming pectinids, the weight of the valves becomes positively allometric to the cube of shell size, indicating remarkable relative thickening of the shell. The decrease of umbonal angle, abrupt inward bending of the shell surface, and disappearance of anterodorsal and postero-dorsal gapes also suggest rapid loss of swimming ability in the middle stage. After it escaped from predators in the young stage, this pectinid probably abandoned a swimming strategy and became an immobile recliner on soft substrates. F. takahashii is thus regarded as an exceptional Cainozoic bivalve which succeeded, though only temporarily, in resurrecting Mesozoic-type reclining life habits in some inland seas of the north-western Pacific region.
PalAss Go! URL: | Twitter: Share on Twitter | Facebook: Share on Facebook | Google+: Share on Google+