Aspects of territoriality and microhabitat selection in Acunthoclinus fuscus and Forsferygiun nigripenne rubustum were studied in intra-and interspecific confrontation experiments under tidal and constant conditions. In both species aggressive responses were closely related to activity with maximal frequencies during the first 2 h of the experiments. Under tidal conditions activity was higher than at constant water level. Size predominantly affected contest outcome in both species. Initiation of the first bout and past experience were further important factors, whereas prior residence did not influence dominance relationships. Dominant individuals defended access to shelter and low tide pools as critical resources. A . fuscus preferred tubes matching the body size for cover, whereas F. n. robustum spent more time in caves and on open areas. Furthermore, A . ,fuscus preferred shallower water and was able to sustain long periods out of water. The different microhabitat preferences may reduce interspecific competition. Although A . fuscus did not win significantly more trials, higher aggressive tendencies were observed in this species.

Abstract. Waitkera waitakerensis occupies lowland forests of New Zealand's North Island, where temperatures decrease in a southwestward direction. The mean annual temperatures of 18 collecting sites, as extracted from GIS data, are directly related to the first femur length of adult females. Neither site elevation nor phylogeny affected spider size or other variables examined. The direct relationship between spider body size and environmental temperature followed a pattern observed in other terrestrial arthropods with a univoltine life cycle and can probably be explained by the longer growing season of warmer regions. Egg diameter was uniform across the species. Site temperature and female first femur length were each directly related to the number of eggs deposited in egg sacs. The date of egg sac collection was inversely related to egg number, suggesting that clutch size declines during the reproductive season. Females deposit eggs beneath a triangular platform and then cover them with a lower silk sheet. The area of this upper platform and the volume of the egg sac were each directly related to egg number, but not to female first femur length. The depth of the lower covering was not related to egg number or to spider first femur length. This suggests that spiders use information about the volume of eggs in their abdomens to construct an egg sac whose volume will accommodate the volume of eggs to be laid and that females do so principally by adjusting the size of the sac's upper triangular platform.

Members of the genus Amaurobioides construct silk retreats in rock crevices of the marine spray zone, a harsh and unusual habitat for spiders. This study expands the distribution records of three morphological species of Amaurobioides found on the eastern and southern coasts of New Zealand's South Island and uses mitochondrial DNA to examine their relationships and characterize their dispersal capabilities. Both 16S and ND1 sequences distinguish A. pletus found on the northeastern coast from a complex of two southern species comprised of A. maritimus from the mainland and A. picunus from Stewart Island. Neither 16S DNA nor ND1 protein separates these southern species. However, ND1 parsimony and likelihood analyses place 10 of 11 Stewart Island specimens in a clade of low support that nests deeply within A. maritimus. A nested haplotype analysis characterizes A. maritimus and A. picunus populations as having restricted gene flow/dispersal but with some long distance dispersal. Genetic distances between A. pletus and the A. maritimus-A. picunus complex indicate a Pliocene origin, whereas distances between A. maritimus and A. picunus suggest a Pleistocene divergence.

Population density, seasonal abundance fluctuations, and habitat preferences of Acanthoclinus fuscus and Forsterygion nigripenne robustum were studied in the rocky intertidal zone at Kaikoura, New Zjaland, from August 1988 to June 1989. Monthly recaptures of marked fishes showed that A. fuscus was common on rocky platforms with small shallow pools; F. n. robustum occurred under larger stones and in deeper channels or larger pools. Most captured A. fuscus were juveniles and adolescents; no seasonal fluctuation in abundance was recorded. The intertidal A. fuscus populations at Kaikoura and Auckland were similar in growth rate and condition factor but differed in age structure. The intertidal population of F. n. robustum was dominated by mature fish; the highest abundance was recorded during the winter spawning season. Each monthly sample of A. fuscus included 40% recaptures, significantly more than in F. n. robustum samples. 31% of displaced A. fuscus returned to their original pool within 1 day and 58% within 1 week.

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