A review of the New Zealand recent and fossil species ofBuccinulumdeshayes (Mollusca : Neogastropoda : Buccinidae)

Abstract

Abstract THE Recent and fossil New Zealand species of Buccinulum are reviewed and the variation and polymorphism within many of the species are discussed. The total number of Recent and fossil Buccinulum species and subspecies in usage at the time of writing is 49, of which 24 species and subspecies are recognised here. The subgenera Evarnula Finlay and Euthrena Iredale and the genus Tasmeuthria are considered to be synonyms of Buccinulum s. str. The type species of Buccinulum, B. lineum Martyn, is shown to be a very variable species including the forms previously known as striatum Hutton, fuscozonatum Suter, costulatum Suter, dubium Marwick, thomsoni Marwick, sufflatum Finlay, characteristicum Finlay, caelatum Powell, decoratum Powell, multilineum Powell, squalidum Powell, waitangiensis Powell, gracillimum Powell, and aupouria Powell. Buccinulum caudatum is here regarded as a fossil subspecies of lineum, whereas flexicostatum Dell is a deepwater representative of the species. A new name, pallidum powelli, is provided for lineum of recent authors, while pallidum pallidum Finlay is a composite of pallidum and tenuistriatum Powell. A complex species, vittatum Quoy and Gaimard, is shown to consist of four geographic subspecies: vittatum vittatum (with maketuense Powell, heteromorphum Powell, bucknilli Powell, and motutaraense Powell as synonyms) in the northern half of the North Island; vittatum colensoi Suter on the south-eastern coast of the North Island; vittatum littorinoides Reeve (with martensianum Hutton, flavescens Hutton, strebeli Suter, mestayerae Powell, kaikouraense Powell, and exsculptum Powell as synonyms) in the southern part of the North Island, the South Island, and the subantarctic islands; and vittatum bicinctum Hutton at the Chatham Islands. Pisania media Hutton is regarded as an ancestral form of vittatum, and B. wairarapaensis Powell is also closely allied. In the southern half of the South Island and at the subantarctic islands lineum is replaced by pertinax Martens (with marwicki Finlay, mutabile Powell, and stewartianum Powell as synonyms), which has a deepwater subspecies finlayi Powell, of which benthicola Dell is a synonym; and an ancestral form, pansum Marwick, is here also regarded as a subspecies. Buccinulum robustum Powell (of which suteri Powell is a synonym) and B. mariae Powell are restricted to the northern part of the North Island. The fossil species compactum Suter is considered to be the same as crassatinum Powell, and tetleyi is a subspecies. Buccinulum grindleyi Marwick, B. protensum Powell (with longicolle Powell as a synonym), B. rigidum Powell, and B. tuberculatum Powell are also fossil species. B. ectypum Marwick and B. scottae Marwick are removed from Buccinulum to Falsicolus and Taron respectively.