Torlessia mackayi and other foraminifera from the Torlesse Terrane, New Zealand

Abstract

Fossils recovered from the Rolleston Range, Canterbury, are identified as belonging to the foraminiferal genus Hormosina. Comparison of the wall structure of these Hormosina and the common tube fossil Torlessia mackayi suggest that this too is a foraminifer rather than an annelid. Confirmation of this comes primarily from the discovery of several hundred specimens of T. mackayi in an outcrop near Sinclair Head, southwest Wellington. This has allowed a relatively broad range of variation within T. mackayi to be appreciated. A close comparison of this population with the foraminiferal genus Bathysiphon reveals that the two forms are almost identical. However, the presence of longitudinal striations on T. mackayi is sufficient to preclude incorporation of this species within Bathysiphon. Hence, the genus Torlessia is here transferred to the foraminiferal family Bathysiphonidae Avnimelech, 1952.

Keywords:

• Hormosina
• Torlessia mackayi
• foraminifera
• Bathysiphonidae
• Torlesse Terrane