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Three new species of caddis in the endemic New Zealand genus Alloecentrella Wise, 1958 (Trichoptera: Sericostomatoidea) are named and described: A. linearis sp. n., A. cirratus sp. n., and A. incisus sp. n. We report the known distribution of each of the four species in the genus; A. magnicornis and A. incisus appear to be found only in North Island; A. linearis and A. cirratus have been recorded only from South Island. We provide characters to differentiate the larvae (extent of the head carina; the shape of the head capsule in lateral profile) and cases (position of the terminal aperture). We present the results of a phylogenetic analysis of larval, pupal and adult morphological characters which places Alloecentrella in the Helicophidae.

Diadromous fish species dominate the New Zealand freshwater fish fauna and make up 15 of the 17 native fish species found on the Taranaki Ring Plain. Trajectories of occurrence in relation to elevation and distance from the sea are described for 11 diadromous and 2 non‐diadromous species using data from the New Zealand Freshwater Fish Database and data collected over the summer of 1997/ 98. Distinctive distributions were found for most of the species related to their differing migratory strategies and abilities. The species were ranked based on components of these trajectories to compare their penetrative ability. Comparison of the ranking methods used revealed they produced similar results. The ranking of the 11 diadromous species in Taranaki relative to each other revealed similar rankings to those for the same species from the West Coast of the South Island. The non‐migratory native fish, Cran's bully (Gobiomorphus basalis), was not found on the western side of the mountain. This distribution ...

We report the results of three independent light‐trapping studies of caddis (Trichoptera) at three widely‐separated stream‐side sites in New Zealand. A total of 66 caddis species in 10 families was recorded, as follows: 33 from site K (Kawarau Gorge) in 1990–91, 28 from site T (Turitea Stream) in 1986–87 and 45 from site W (Waitakere Stream/Cascade Stream) in 1967–68. Many of the species were captured in sufficient numbers to estimate their adult flight season. The results show that some species in the families Hydrobiosidae, Hydroptili‐dae and perhaps also Philopotamidae and Chathamiidae are present as adults during every month of the year. Species captured from 7 other families appeared to have a mid‐winter break with no active adults present. For some species there is a marked change in the sex ratio through the flight season from predominantly males early in the season to predominantly females at the end. For four common species at one site, the arrival pattern at the light trap was unimodal. It was h...

Regression equations are presented for the estimation of dry weight from head width and body length for 20 common New Zealand stream‐dwelling macroinvertebrate taxa. Equations for taxa grouped at order level are also provided. A power equation, y = a x b is used to express the relationship between dry weight and body size. For the majority of taxa, dry weight could be estimated with more precision from body length than from head width.