Pebasiconcha immanis

Pebas lineup, Colombia; Peru

Pebasiconcha immanis (synonym: Amazoniconcha immanis ) is a fossil Landschneckenart from the family Acavidae within the order of snails ( Pulmonata ). She lived from the middle Miocene to the Lower Upper Miocene in the western Amazon basin.

The two largest case of Pebasiconcha immanis have heights of 22 centimeters and 25 centimeters. In order for this taxon is the largest known fossil Landschneckenart. The first case was discovered in the Pebas formation in Colombia in 1991. It was photographed in situ, however, broke into several pieces during transport. 1996 an undamaged specimen was acquired in a tourism business in Iquitos, Peru, which also comes from the Pebas formation. Both cases are kept in the Museum Naturalis in Leiden. There are also smaller fragments of lignite deposits in Peru.

The housing turns are very large, but the mouth had grown significantly compressed. Behind the top of the outer lip is a solid nub on the outer side of the housing.

The size of Pebasiconcha immanis suggests that it was a bottom dweller. On the other hand, indicates the nature of the deposits in which the species was found out that the living room was originally a large lake with marshes and swamp forests. Therefore, it is not unlikely that this type at least spent part of their lives in trees.