A SUSPECTED CASE OF MYCOPHYCOBIOSIS BETWEEN MYCOSPHAERELLA APOPHLAEAE (ASCOMYCETES) AND APOPHLAEA SPP. (RHODOPHYTA)1

Apophlaea lyallii Hooker f. et Harvey and A. sinclairii Harvey in Hooker et Harvey, endemic Rhodophyta from New Zealand, were found to harbor a systemic fungus, Mycosphaerella apophlaeae Kohlmeyer. The algae occur on rocks in the upper intertidal zone and are resistant to desiccation and insolation. These suspected symbiotic associations which are similar to, but different from, lichens, are considered mycophycobioses. This is the first report of a supposed mycophycobiosis in members of the Rhodophyta.     

The grazing effect of limpets on the macroalgal community of a rocky intertidal shore

Abstract Abundance of macro-algae in the mid-littoral zone on a Victorian intertidal rocky shore varied seasonally, algae being rare in Summer and common in Winter and Spring. Field experiments demonstrated that, of two species of grazing limpets (Cellana tramoserica and Siphonana diemenensis), only Siphonaria had a major effect on the abundance of foliose algae (e.g. Scytopsiphon lomeniarid) and neither species had a great effect on the encrusting algae (Ralfsia spp.). There was no evidence of competition for food between the two species of limpets, in contrast with results found for similar species in New South Wales.     

Uptake of phosphate and inorganic nitrogen by a sediment-algal system in a subarctic lake

SUMMARY.

• 1 The uptake of phosphate and inorganic nitrogen by sediment and phytoplankton was studied under natural conditions (1977) and during lake fertilization with phosphorus and nitrogen (1978–79) in Lake Gunillajaure, a small, stratified, subarctic lake in northern Sweden. The experiments were performed in situ in plexiglass cylinders, to which additions of nutrients were made, and the uptake followed by consecutive sampling and analysis of the water phase.
• 2 Additions of HgCl₂ to the experimental vessels reduced the phosphate uptake to the sediment to less than 10% and it could therefore be concluded that the sediment uptake was mainly of biological nature.
• 3 Dark assimilation was 30–40% of that in light. Since light clearly stimulated the sediment uptake the epipelic algae were probably responsible.
• 4 The phosphate uptake to the sediment could be described by Michaelis-Menten kinetics and the calculated constants (V_max, ks) were very alike in 1977 and 1978 but appeared to have increased in 1979.
• 5 The sediment uptake of ammonium and nitrate was very slow indrcating that the epipelic algae were not nitrogen starved.
• 6 Even though the epipelic algae had a potential for efficient uptake of phosphorus, the phytoplankton took up 92–96% of the phosphate added to the lake on each fertilization occasion due to the relatively large water volume in the epilimnion in relation to the bottom area available for the epipelic algae.

     

Characterisation of microsatellite loci in the habitat-forming kelp, Ecklonia radiata (Phaeophyceae, Laminariales)

Habitat forming algae play an important role in the ecology of temperate reefs worldwide. Despite this, our understanding of levels of gene flow within and among populations of algae is largely limited to studies on intertidal species; we know comparatively little about important habitat-forming subtidal algae. Here, we develop eight polymorphic microsatellite markers for the characterisation of population genetic diversity and structure in the subtidal kelp, Ecklonia radiata. This large macroalga is the most abundant habitat-forming kelp on the subtidal rocky reefs of temperate Australia and New Zealand where it forms extensive forests that support an astounding diversity of associated taxa.     

Host range testing for risk assessment of a sexually dimorphic polyphagous invader,painted apple moth

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Relative importance of competition with Daphnia (Cladocera) and nutrient limitation on Anuraeopsis (Rotifera) population dynamics in a laboratory study

• 1 In the laboratory, the growth and reproduction of Anuraeopsis fissa were measured when fed on Scenedesmus species grown in nutrient‐sufficient, nitrogen‐limited and phosphorus‐limited media and in the presence or absence of one adult Daphnia longispina per vial.
• 2 Poor food quality may reduce the effect of competition on rotifers. Competition from Daphnia was stronger with nutrient sufficient algae than with nutrient limited algae. P‐limitation significantly reduced Anuraeopsis population growth rate and fecundity. The effect of nutrient limitation on Anuraeopsis was stronger than that of competition with Daphnia. The Anuraeopsis population declined with P‐limited food in both the presence and absence of Daphnia.
• 3 Exploitative competition by Daphnia on Anuraeopsis was stronger in the nutrient‐sufficient treatment than in the N‐limited one. Density, fecundity and population growth rate of Anuraeopsis were negatively affected by Daphnia in the nutrient‐sufficient treatment, while only fecundity was reduced by Daphnia in the N‐limited treatment. Consequently, in the N‐limited treatment, mortality should be lower in the presence of Daphnia. This result could suggest that Anuraeopsis lives longer when short of nitrogen.
• 4 Nutrient limitation may affect to the competitive interactions between zooplankton species. P‐limitation decreased the quality of algae as food for Anuraeopsis while N‐limitation decreased the susceptibility of this rotifer species to exploitative competition by Daphnia.

     

Genetic structure of an introduced paper wasp,Polistes chinensis antennalis (Hymenoptera,Vespidae) in New Zealand

Several eusocial wasps are prominent invaders to remote islands. The paper wasp Polistes chinensis antennalis is native to East Asia, was introduced to New Zealand in 1979 and has expanded its distribution there. This provides an excellent opportunity to examine the impacts of an initial bottleneck and subsequent expansion on genetic structure. We analysed and compared the genetic population structures of the native (Japan and South Korea) and invasive New Zealand populations. Although 94% of individuals had shared haplotypes detected across both populations, the remaining 6% had private haplotypes identified in only one of the three countries. The genetic variation at microsatellite loci was lower in New Zealand than in native countries, and the genetic structure in New Zealand was clearly distinct from that in its native range. Higher frequencies of diploid‐male‐ and triploid‐female‐producing colonies were detected in New Zealand than in the native countries, showing the reduction in genetic variation via a genetic bottleneck. At least two independent introductions were suggested, and the putative source regions for New Zealand were assigned as Kanto (central island) and Kyushu (south island) in Japan. Serial founder events following the initial introduction were also indicated. The estimated dispersal distance between mother and daughter in New Zealand was twice that in Japan. Thus, the introduction history of P. chinensis antennalis in New Zealand is probably the result of at least two independent introductions, passing through a bottleneck during introduction, followed by population expansion from the point of introduction.     

Evolution and phylogeny of the New Zealand cicada genus Kikihia Dugdale (Homoptera: Auchenorrhyncha: Cicadidae) with special reference to the origin of the Kermadec and Norfolk Islands' species

Aim Determine the phylogeny and dispersal patterns of the cicada genus Kikihia in New Zealand and the origin of the Norfolk, Kermadec, and Chatham Island cicadas. Location New Zealand, Norfolk Island, Kermadec Islands and Chatham Island. Methods DNA sequences from 16 species and four soon to be described species of cicadas from New Zealand and Norfolk Island (Australia) were examined. A total of 1401 base pairs were analysed from whole genome extraction of three mitochondrial genes (cytochrome oxidase subunit II, ATPase6 and ATPase8). These DNA sequences were aligned and analysed using standard likelihood approaches to phylogenetic analysis. Dates of divergences between clades were determined using a molecular clock based on Bayesian statistics. Results Most species in the genus Kikihia diverged between 3 and 5 million years ago (Ma) coincident with a period of rapid mountain building in New Zealand. Cicada species on the Kermadec and Norfolk Islands invaded recently from New Zealand and are closely related to the New Zealand North Island species Kikihia cutora. Main conclusions Speciation in the genus Kikihia was likely due in large part to the appearance of new habitats associated with the rise of the Southern Alps, starting c. 5 Ma. Dispersal of Kikihia species within mainland New Zealand probably occurred gradually rather than through long‐distance jumps. However, invasion of Norfolk, the Kermadecs and Chatham Islands had to have occurred through long‐distance dispersal.     

In situ light and phosphorus manipulations reveal potential role of biofilm algae in enhancing enzyme‐mediated decomposition of organic matter in streams

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Competition between Cellana tramoserica (Sowerby) (gastropoda) and Patiriella exigua (Lamarck) (asteroidea), and their influence on algal standing stocks

Caging experiments were undertaken in the field to test if competition occurs within and between the limpet Cellana tramoserica (Sowerby) and the starfish Patiriella exigua (Lamarck). Both species suffer from intraspecific competition, even at natural densities, and increased density reduces body weight and survival in Cellana tramoserica and growth rate in Patiriella exigua. Cellana tramoserica depresses the growth of Patiriella exigua, while the starfish unexpectedly seems beneficial to Cellana tramoserica, increasing its body weight. The difference in these effects may be due to the divergent methods of feeding used by the two species. C. tramoserica digs into the substratum and removes most available microflora, while Patiriella exigua everts its stomach onto the rock face and can only remove superficial or loosely attached microflora and detritus, and leaves a mucous web which may supplement the diet of Cellana tramoserica. Even at low densities C. tramoserica can completely prevent macroalgae from developing, while Patiriella exigua is unable to do so, although it shows the rate of development. Macroalgae grew in all the cages which contained only P. exigua, but in spite of this the starfish still suffered from intraspecific competition, probably because they cannot feed on macroalgae. Cellana tramoserica also competes by interference, and on contact with Patiriella exigua it extends its mantle and pallial tentacles, both of which may release mucus. P. exigua retreats from Cellana tramoserica, and those parts of its body that have been touched by the limpet may temporarily be immobilised and become wrinkled up. It is suggested that this interference behaviour by C. tramoserica is derived from a similar but more intense reaction that it has to invertebrate predators. Patiriella exigua lacks a pelagic larva and does not have a refuge outside the range of Cellana tramoserica. Other factors must thus be sought to explain the continued coexistence of Patiriella exigua with Cellana tramoserica. It is suggested that although C. tramoserica has a competitive effect on Patiriella exigua, it (and other grazers) may be necessary for P. exigua, preventing macroalgal growth and maintaining a surface suitable for P. exigua to feed on.     

Assessing the role of off‐take and source–sink dynamics in the extinction of the amphidromous New Zealand grayling (Prototroctes oxyrhynchus)

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The influence of habitat use and foraging on the replacement of one introduced wasp species by another in New Zealand

Abstract.

• 1 New Zealand was colonized by the German wasp, Vespula germanica (F.), in the 1940s and it subsequently became established throughout the country. The common wasp, V.vulgaris (L), colonized in the late 1970s and is still spreading.
• 2 The common wasp has replaced the German wasp in some habitats in New Zealand. Samples from a nationwide postal survey indicate that the common wasp is now the more abundant species in honeydew beech forests (Nothofagus spp.), and to a lesser extent in other native forests. The German wasp is still the more abundant wasp in rural areas (excluding forest). The two species are at present co-dominant in urban areas, although this may be a transient phase.
• 3 In honeydew beech forest the two species show different foraging patterns that provide the potential for local coexistence. Although both species are generalist feeders, the German wasp is more commonly found foraging for protein amongst the forest litter, whereas the common wasp forages more on shrubs and tree saplings. Despite this difference, the common wasp can still replace the German wasp in honeydew beech forest within a few years of invasion.
• 4 In honeydew beech forests in which the German wasp is the more abundant species it dominates honeydew trunks (sugar resource), whereas the common wasp dominates honeydew trunks in areas where it is the more abundant species. The change from German to common wasp domination of honeydew trunks is more rapid than the change in dominance in other microhabitats. Aggressive interactions may be taking place on this high quality, potentially defensible sugar resource.

     

Asexual reproduction and somatic growth of the fissiparous sea star Allostichaster polyplax in New Zealand

Allostichaster polyplax is a fissiparous (capable of reproducing asexually by fission) sea star found in intertidal and shallow subtidal habitats in New Zealand and Australia. A localized population of A. polyplax occurred at a density of 2.7?individuals?m^?2 in an intertidal boulder field at Otago Harbour, South Island, New Zealand. The percentage of sea stars undergoing fission, recorded from January 2010 to March 2011, peaked in January (midsummer) in both years. The frequency of fission decreased for larger sea stars (mean arm length, R?>?25?mm), suggesting an ontogenic shift from asexual to sexual reproduction. Effects of fission (i.e. arm regeneration) and food availability (small gastropods) on growth, storage and sexual reproduction were examined in a factorial laboratory experiment. There was no effect of arm regeneration or food on total arm growth. Storage capacity, measured as pyloric caeca index (PCI), was greater in full-armed than regenerating sea stars, and greater in fed than starved individuals. Fed individuals had a similar PCI as field-collected ones. Gonads were observed in two individuals (males) in the full-armed and fed treatment. Fission did not occur during the experiment. Feeding rate on snails was greater for full-armed than regenerating sea stars. Water temperature had a weak positive effect on the feeding rate of regenerating sea stars. Our findings suggest that fission and subsequent growth of ramets can sustain demographically stable and geographically isolated populations of A. polyplax. The role of sexual reproduction in population dynamics and connectivity of this species (and fissiparous sea stars in general) remains equivocal and requires further research on genetic differentiation within and among populations.     

Phenological observations and trapping tactics for the granulate ambrosia beetle Xylosandrus crassiusculus (Coleoptera: Curculionidae,Scolytinae) in New Zealand

1. The granulate ambrosia beetle (GAB) Xylosandrus crassiusculus, was first formally detected in New Zealand in 2019. Since then, GAB has subsequently been found infesting numerous tree species in the Auckland region.
2. Flight intercept traps baited with ethanol lures were deployed from October 2019 to May 2021 at three sites in the Auckland region to ascertain the phenology of GAB in New Zealand. Two distinct peak flight periods were identified in early and late summer, while a smaller and inconsistent third peak was detected in early autumn. Logistical analysis of GAB captures in the ethanol-lured traps and degree-day (DD) accumulation indicated that 90% of flight activity is completed by 800 DD.
3. To assess monitoring tactics, flight intercept traps were baited with three different ethanol lures with varying release rates or ethanol-soaked or non-soaked wood bolts from three species of trees. A lure releasing 2 g ethanol per day was most effective at capturing GAB. Ethanol-soaked bolts were less effective than the lures.
4. Xylosandrus crassiusculus represents a significant risk for shrubs and trees native to New Zealand, as well as commercial horticultural and forestry trees. We recommend using ethanol-lured panel traps for monitoring purposes.

     

Potential impacts of Tuberolachnus salignus (giant willow aphid) in New Zealand and options for control

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The potential global distribution of the Bronze bug Thaumastocoris peregrinus Carpintero and Dellapé (Hemiptera: Thaumastocoridae)

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Depth distribution of the native freshwater mussel (Echyridella menziesii) in warm monomictic lakes: Towards a general model for mussels in lakes

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Notes On The Flora Of Caithness

Summary

216 species of diatoms have been found epiphytic on common intertidal marine algae from Great Cumbrae Island, Firth of Clyde, Scotland. Green and red algae had larger epiphytic floras than brown algae. Cocconeis spp. (especially C. scutellum var. scutellum) were common and abundant, and the endophytic Navicula endophytica was found in large numbers in fucoid algae. Similar epiphytic floras were observed on Cladophora rupestris, Polysiphonia lanosa, Gigartina stellata, and Palmaria palmata, but that on Enteromorpha intestinalis was quite distinct.     

Distribution and abundance of fish in a rocky reef environment at the subantarctic Auckland Islands,New Zealand

Summary The distribution and abundance of fish in a rocky reef environment were investigated at the subantarctic Auckland Islands of New Zealand, in June 1986. Fish were counted in transects and specimens were taken. The diversity and abundance of species of large reef fish was low; a total of eight species were observed. Most fish were benthic carnivores. These findings are similar to studies of reef fish in subantarctic waters of Chile. Large differences in species composition were found among locations at the Auckland Islands. The number of species and their abundance was highest near exposed headlands. Few fish were found on reefs at more sheltered inlets. At most locations the nototheniids Paranotothenia angustata and P. microlepidota ranked first in abundance at deep and shallow sites. There were some species that showed differences in abundance with depth. Highest abundance of Bovichthys variegatus, Latridopsis cilaris, Latris lineata and Pseudolabrus cinctus were in deep water on reefs. Large numbers of juvenile P. microlepidota were found only in shallow water. No depth related patterns were found for P. angustata and Mendosoma lineatum. Specimens, other than those counted in transects, were also collected. There were small fish, 4 species of tripterygiids, 1 gobiescocid and 2 syngnathids. The Auckland Islands had closer zoogeographic affinities with islands of temperate and subantarctic New Zealand than with other landmasses of the westwind drift. Although most fish found at the Auckland Islands are found also in temperature New Zealand, the converse of this pattern was not found. The proportional representation of species and trophic groups differed markedly between these regions.     

Profilicollis novaezelandensis n. sp. (Polymorphidae) and two other acanthocephalan parasites from shore birds (Haematopodidae and Scolopacidae) in New Zealand,with records of two species in intertidal crabs (Decapoda: Grapsidae and Ocypodidae)

Profilicollis novaezelandensis n. sp. (Acanthocephala: Polymorphidae) is described from the South Island pied oystercatcher Haematopus ostralegus finschi Martens (Haematopodidae) and the intertidal crab Hemigrapsus crenulatus (Milne Edwards) (Brachyura: Grapsidae) from the South Island of New Zealand. The new species can be distinguished from all the other species of the genus by a combination of the following characters: long neck (13% of total body length for adults) and a subspherical proboscis with 14–16 longitudinal rows of 7–8 hooks. The mud crabs Helice crassa Dana (Grapsidae) and Macrophthalmus hirtipes (Heller) (Ocypodidae) were also harbouring cystacanths and the bar-tailed godwit Limosa lapponica (Linnaeus) (Scolopacidae) juveniles of P. novaezelandensis. This is the first record of brachyuran decapods as intermediate hosts of Acanthocephala from New Zealand. P. antarcticus is recorded from three crab species (Helice crassa, Hemigraspus crenulatus and Macrophthalmus hirtipes) and two bird species (Haematopus o. finschi and Limosa lapponica) in New Zealand. An unidentified species of Plagiorhynchus was also found in two bird species (H. o. finschi and H. unicolor Forster). P. antarcticus and P. novaezelandensis are the first records of Profilicollis from New Zealand.