Pallial systems in the Athoracophoridae (Gastropoda: Pulmonata)

Abstract

Pallial systems are described for 10 athoracophorid species: Athoracophorus bitentaculatus, Pseudaneitea dendyi, P. gigantea, P. papillata, P. pallida, P. aspera, P. schauinslandi, P. multistriata, and Palliopodex verrucosus from the New Zealand and sub antarctic area; and Triboniophorus graeffei from Australia. In the New Zealand and subantarctic species the kidney is invariably bilobed, the ureter is extensively folded and connected to the intestine by an elongate tubule running initially through the lung, and the pneumostome, anus, and excretory pores are widely sepamted. Triboniophorus graeffei has the pneumostome, anus, and excretory pore closely associated, a compact kidney, and a more simply folded ureter. The New Zealand and subantarctic representatives are considered to be more advanced. Reasons for the development of the features they display are discussed, as is the function and evolution of the entire pallial system. An account of the variation in the pallial complex of Athoracophorus bitentaculatus is included.     

Hugotdiplogaster neozelandia n. gen., n. sp. (Nematoda: Diplogasteridae), a parasite of the New Zealand endemic slug,Athoracophorus bitentaculatus (Quoy & Gaimard, 1832) (Gastropoda: Athoracophoridae)

Abstract

A new genus and a new species are described for nematodes removed from the genital tract of Athoracophorus bitentaculatus in New Zealand. Hugotdiplogaster neozelandia n. gen., n. sp. is different from other genera in the Diplogasteridae by the shape of the stoma and by possessing a very robust and large gubernaculum. It is the first time that a diplogasterid has been reported associated with a mollusc. The localisation of the nematode in the genital tract of slugs raises questions about its life cycle and effect on the host.