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A middle Hettangian marinegastropod assemblage is reported from the Kenai Peninsula of south-centralAlaska supplying new paleontological evidence of this group in rocks of the LowerJurassic of North America. Pleurotomariapogibshiensis sp. nov. is described from the middle Hettangian marinesuccession informally known as Pogibshi formation, being the first occurrenceof the genus in the Kenai Peninsula and the oldest occurrence of the genus inpresent-day Alaska and North America. One species of the genus Lithotrochus, namely Lithotrochus humboldtii (von Buch), is also reported for the firsttime from the Kenai Peninsula. Lithotrochushas been considered as endemic to South America for a time range from the early Sinemurian tothe late Pliensbachian. The newest occurrence of Lithotrochus in rocks of the Pogibshi formation extends thepaleobiogeographical and chronostratigraphical distribution of the genus intothe present-day Northern Hemisphere. However, the Southern Hemisphere affinitiesare consistent with the hypothetical interpretations (although supported bothby paleobiogeographical and paleomagnetic data) that the Peninsular terrane ofsouth-central Alaska is far-traveled and may have originated at much moresoutherly paleolatitudes than its present-day position. Two other EarlyJurassic caenogastropods typical of the Andean region of South America and ofthe Tethyan epicontinental seas are described for the first time in thePogibshi formation, and these are Pseudomelaniasp. and Pictavia sp. The newgastropod assemblage reported here shows close affinities with coeval SouthAmerican and European gastropod faunas, supplying new evidence to interprettheir distribution during the Early Jurassic.