A citizen science project reveals contrasting latitudinal gradients of wing deformity and parasite infection of monarch butterflies in New Zealand

1. Host–parasite interactions represent complex relationships among species, often with considerable spatial variation. We examined latitudinal variation in the prevalence of monarch butterfly (Danaus plexippus) infection by the protozoan parasite Ophryocystis elektroscirrha via a citizen science project in New Zealand. Parasitism by O. elektroscirrha can result in incomplete development causing mortality, or adult butterflies with deformed wings and reduced fitness. 2. We established the existence of counter-latitudinal clines of wing deformities and parasite prevalence in monarchs, which in New Zealand are non-migratory. The prevalence of wing deformities increased with increasing latitude, whereas the prevalence of parasite infections decreased with increasing latitude. No parasitism was observed in our highest latitudinal location, while all butterfly samples were infected in the warmest and lowest latitudinal site. The prevalence of parasitism or wing deformity did not vary with the butterfly sex. 3. Cold temperatures appear to independently affect the parasite and host butterfly development, with lower temperatures limiting parasite development and inducing wing deformities in butterflies. Other protozoan parasites display similar latitudinal clines that are thought to be temperature related. 4. Environmental factors appear to independently influence insect populations through different mechanistic pathways. The high prevalence of parasite infections may affect butterfly fitness in warmer regions, but the cooler conditions at higher latitudes manifest as a major fitness cost, deformed wings. Monarch butterflies in New Zealand and around the world may perform better where it is not too hot (and optimal for these parasites), but not cold (where the pupae experience developmental issues)

A synonymic catalogue of the Acari from Antarctica, the sub-Antarctic Islands and the Southern Ocean

The records, taxonomy and geographical distribution of 528 species of Acari collected from the Antarctic, sub-Antarctic islands and the Southern Ocean are collated. Included are free-living and phoretic mites, parasites and nidicoles associated with a variety of birds, seals and other introduced mammals, from terrestrial aquatic, seashore and benthic marine habitats. A number of these Acari have been introduced by humans, to and around research stations and disused whaling stations. A full alphabetical index to all current higher taxa, as well as current/redundant generic and specific names, is provided