Miocene Argonautidae (Octopoda) from the Persian Gulf area and their palaeogeographic distribution

Cephalopod specimens assigned to the Argonautidae ( Obinautilus pulchra Kobayashi, 1954 and an unknown taxon) from two localities of the Mishan Formation in Gohreh and Khorgu sections, Bandar Abbas, southern Iran, are reported for the first time from the Persian Gulf area. The co-existing foraminifera confirm the middle Miocene age of the strata. Based on micropalaeontological data, the previous Oligocene age of Obinautilus pulchra is extended to the middle Miocene. The palaeobiogeographic distribution of the reported Argonautidae shows that the presence of these faunas is limited to the West Pacific, Indo-Pacific and the East Pacific. The present-day distribution of the Argonautidae is similar to the ancient one and seems to be inherited from their ancestors.