Classification of New Zealand Arionacea (Mollusca : pulmonata). A revision of some endodontid genera (Endodontidae Pilsbry, 1894).

Abstract

The following systematic revisions of New Zealand taxa within the Arionacean subfamilies Flammulininae Climo, 1969, Otoconchinae Cockerell, 1893 and Endodontinae Suter, 1913 (family Endodontidae Pilsbry, 1894) are based on quantitative reappraisals of shell morphology and studies on radular and soft-part morphology. The last major revision of these New Zealand pulmonate taxa was presented by Suter (1 913) i n his Manual of the New Zealand Mollusca, and illustrated in his Atlas of Plates which appeared in 1915. Suter’s work was, as were the great majority of earlier pulmonate systematic studies, based on studies of shell and radular morphology, and was the major contribution towards the erection of a systematic hierarchy which illustrated the indigenous nature of the New Zealand endodontid fauna. Systematic studies on Australian and New Zealand endodontids by the contemporary worker T. Iredale resulted in the replacement of Suter1s hierarchy which was influenced by the earlier works of H. A. Pilsbry. Iredale’s higher classification of the New Zealand endodontid fauna has been followed in Australia and New Zealand to the present day, but not without question. The introductory paper in the series which comprises this thesis elaborates on, and shows that the doubts held about the Iredalian higher systematics can be substantiated. I was influenced by statements made by Solem (1959) to undertake an anatomical study of the New Zealand representatives of the family Endodontidae Pilsbry, 1894. Solem and other workers have mentioned that the distinction between Charopidae Iredale, 1937 and Flammulinidae Iredale, 1937 was artificial. Solem also stated that to understand the generic relationships within the large, diverse group of molluscs which he classified in the redefined subfamily Endodontinae Suter, 1913 (Charopidae and Flammulinidae), anatomical studies would have to be undertaken. Having shown that the distinction between Charopidae and Flammulinidae was artificial (Part I), I then proceeded to systematically dissect all available New Zealand species within the redefined subfamily Endodontinae. The results of these dissections have provided information which enables the Endodontinae to be divided into two taxa: the subfamilies Endodontinae and Flarnmulininae Climo. Having established this higher systematic platform I then revised the existing taxa in light of the new anatomical data and information provided by studies in shell variation. The revisions as here presented are part of a long term study which will eventually result in a review of the entire New Zealand endodontid fauna. Lack of material and the time necessary to revise some genera in the Flammulininae, and the large punctid complex (Punctinae Morse, 1864) has made it impracticable to include a revision of these taxa in this thesis.