Penion winthropi is an extinct species of marine snail or whelk, belonging to the true whelk family Austrosiphonidae.
Distribution Fossils of Penion affixus are found in the Upper Cenozoic strata of Wairoa District, New Zealand.
References
Marwick, J. (1965) Upper Cenozoic Mollusca of Wairoa District, Hawke's Bay. New Zealand Geological Survey Paleontological Bulletin, 39, 1–83. Maxwell, P. A. (2009). Cenozoic Mollusca. Pp 232-254 in Gordon, D. P. (ed.) New Zealand inventory of biodiversity. Volume one. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. Canterbury University Press, Christchurch.