Invertebrates associated with the marine wood boring isopod,Limnoria tripunctata

Summary Untreated wood submerged for 4–6 months and infested with the marine wood boring isopod, Limnoria tripunctata Menzies, was analyzed for the associated invertebrate community. Associated with Limnoria were acoelous turbellarians, nematodes, the archiannelid Dinophilus sp., the tubicolous polychaete, Polydora sp., 4 harpacticoid copepods, 2 amphipods and the tanaid, Leptochelia savignyi. Limnoria ecto-commensals included ciliated and diatoms.Prior to dying Limnoria dug tomb-like side tunnels and then crawled inside to expire. All previous reports suggest that Limnoria leaves the wood to die.     

New Harpacticoida (Crustacea, Copepoda) from the North Atlantic Ocean. VIII. The description of Eurycletodes (Oligocletodes) quadrispinosa sp.n. and the male of E. (O.) monardi Smirnov (Cletodidae)

Eurycletodes (O.) quadrispinosa Sp.n. and the male of Eurycletodes (O.) monardi are described. E. quadrispinosa differs from the closely related species E. echinatus Lang, E. parasimilis Por and E. arcticus Lang in the setation of segment 1 and 2 Exp P2–P4, of segment 2 Exp p24 and of the Exp P5. Because of the same setation of the A2, Pl-P4 Exp and Exp as the female of E. monardi Smirnov the described male is regarded as that of E. monardi Smirnov. The species were collected at the Iceland Faroe Ridge from depths of 500. 1540 and 2500 m.     

A new species of Hemicyclops (Copepoda, Poecilostomatoida) from burrows of the mud shrimp Upogebia major in an estuarine mud-flat in Tokyo Bay, Japan

A new species of poecilostomatoid copepod, Hemicyclops tanakai n. sp. was collected from burrows of the mud shrimp Upogebia major in an estuarine mud-flat in Tokyo Bay. The new species can be distinguished from its congeners by combination of the following characteristics: setation of the antennule, the segmentation of the antennule, the length–width ratio of the caudal ramus, the ornamentation on the third segment of antenna and the shape of the genital double somite.     

Feeding modes of deep-sea lobsters (Crustacea: Decapoda: Nephropidae and Palinuridae) in Northwest Pacific waters: Functional morphology of mouthparts, feeding behaviour and gut content analysis

The setation of the mouthparts, gut contents and video recordings of live individuals of the deep-sea clawed lobsters (Nephropidae) Metanephrops formosanus, M. armatus and the spiny lobster (Palinuridae) Puerulus angulatus from northwest Pacific waters were analysed to get an insight into their feeding modes. A comparison of SEM photos shows a high degree of similarity between the morphology and setation of the mouthparts of M. formosanus and M. armatus, but that of P. angulatus was very different to Metanephrops. Serrate setae are most abundant on the feeding appendages of M. formosanus and M. armatus. The mouthparts of P. angulatus are dominated by simple and cuspidate setae. Gut contents of Metanephrops spp. contained small crustacean parts, fish and bivalves and a considerable amount of sediment (∼60% relative abundance). Guts of Puerulus contained mostly small pieces of fish and crustaceans and only a relatively minor amount of sediment (<10%). Video analysis revealed that the studied Metanephrops species are able to handle soft food items by cutting and abrading movements of the mouthparts. Puerulus would not feed on presented food items under lab conditions. The feeding appendages and their setation are clearly related to the feeding modes of the species studied. Both Metanephrops species have slender appendages with fine and sharp setae, suggesting it is a predator and/or scavenger on small crustaceans and ingest deposits to a limited extent. Puerulus angulatus has thick and shorter appendages with strong simple and cuspidate setae, possibly corresponding to a more predatory lifestyle.     

A revision of Danielssenia perezi Monard, D. paraperezi Soyer, D. eastwardae Coull (Harpacticoida; Paranannopidae) and their transfer to a new genus

The harpacticoid copepod Danielssenia perezi Monard, 1935 is redescribed on the basis of the only available material from the Scilly Isles off south-west Britain. Sentirenia gen. nov is erected because this species exhibits significant differences from the type species Danielssenia typica Boeck, 1872 in the structure of the antennule; the presence of sensory aesthetascs on, and structure of, the mandible, maxillula and maxilla; the form of the female P5; the setation of the swimming legs and details of the sexual dimorphism on the endopod of the male P2. Further, it is shown that the characters by which D. paraperezi Soyer, 1970 was originally distinguished from D. perezi are no longer valid and D. paraperezi is a junior synonym of S. perezi which now assumes a boreo-mediterranean distribution. A re-examination of the type material of D , eastwardae Coull, 1971 shows that this species is identical to S. perezi in the structure of the mouthparts (including the presence of aesthetascs on the mandible, maxillula and maxilla) and setation of P1–P5. However, within the genus Sentirenia, its specific status is maintained by virtue of a 5-segmented female antennule; a difference in the shape of the endopodal lobe of the female P5; the sexually dimorphic characters of the male P2 endopod; and variation in the ornamentation of some appendages.     

The Role of the Predaceous Copepod Parabroteas Sarsi in the Pelagic Food Web of a Large Deep Andean Lake

Parabroteas sarsi is a predaceous calanoid copepod that inhabits both shallow temporary fishless ponds and deep fish lakes of Patagonia and Antarctica. The aim of this study was to analyse the effect of P. sarsi on the plankton structure of a deep Andean lake (>100 m depth) and the zooplankton vertical distribution in order to asses a possible vertical refuge of the predatory copepod against visual fish predation. We tested the extent to which the trophic cascade effect of this predator propagates through the food web. We carried out a vertical sampling in Lake Rivadavia (Patagonia, Argentina) in order to assess zooplankton distribution. P. sarsi showed a vertical distribution towards deeper layers of the water column both at midday and at night, indicating that the copepod had an effective refuge against visual predation. Additionally, we carried out both field and laboratory experiments with the presence of P. sarsi. The predator was observed to affect significantly the survival of the copepod Boeckella michaelseni both in laboratory and field experiments. On the contrary, rotifers and adults of Daphnia cf. commutata were not substantially affected by the predator. B. michaelseni mouthparts revealed an omnivorous diet; therefore a broad phytoplanktonic size spectrum could be affected by this copepod. However, no cascade effect was observed due to the presence of P. sarsi despite the decrease of B. michaelseni abundance.     

A laboratory assay for measuring feeding and mortality of the marine wood borer Limnoria under forced feeding conditions: A basis for a standard test method

Quick simple testing methods are needed to evaluate alternative wood materials for marine construction because traditional borer resistant materials are becoming scarce or are no longer permitted due to concerns over environmental emissions of preservatives. Laboratory tests can provide species-specific information on rates of wood biodeterioration by wood borers under optimum conditions, in contrast to field trials where more than one borer species may be present and conditions are variable.The methodology described herein relies on the assumption that faecal pellet production rate in limnoriids must match feeding rate quite closely. Thus, the number of faecal pellets produced by individual specimens of Limnoria quadripunctata, while feeding on a non-durable and non-toxic wood species – Pinus sylvestris sapwood – in different test conditions, was monitored over a period of 15 days. Mortality and moulting were also registered. Several variables likely to affect survival and feeding rates were investigated in order to optimise the test conditions. Temperature and salinity regime affected both survival and feeding rates while moulting cycle affected feeding rates.The optimisation of this test methodology aims to provide the basis for a standard laboratory test with the wood-boring crustacean Limnoria.     

Developments in the understanding of the biology of marine wood boring crustaceans and in methods of controlling them

The most economically important wood boring Crustacea belong to the isopod families Sphaeromatidae and Limnoriidae, both of which have been recently revised and a number of new species have been recognised. Other wood boring crustaceans have now been recognised from tropical mangrove sites. Limnoriids are found from temperate to tropical waters, but appear to be restricted to waters with salinities close to that of seawater. Wood-boring species of Sphaeroma on the other hand can tolerate extremely low salinities, but are restricted to sub-tropical and tropical waters. Approaches to borer control that have proved effective against teredinids (use of naturally durable timber, copper-chrome-arsenic or creosote treatment, surface coatings) have been found under certain circumstances to be ineffective against Limnoria and Sphaeroma. A number of additives to conventional preservatives have been tested, with some insecticides showing evidence of enhancing Limnoria control. The question of crustacean borer nutrition may hold the key to problems of their control. Sphaeromatid borers are capable of filter-feeding and thus may never ingest the treatments applied to wood. Limnoriids do ingest wood, but the role of wood degrading tunneling bacteria, and soft-rotting ascomycete and deuteromycete fungi occurring in the wood they digest remains to be fully elucidated. The source or sources of wood-degrading enzymes that permit digestion of wood particles requires further investigation. The microecology of borer burrows has an important bearing on the availability of nitrogen for borers. Further insights into the problems posed by these borers may be obtained with a better understanding of their ecology. A better testing protocol for preservatives has been developed as a result of knowledge of the natural vertical distribution of Sphaeroma. Behavioural studies indicate that settlement on wood by Limnoria is enhanced by factors derived from conspecifics and from wood-inhabiting microorganisms.     

Selective grazing of Temora longicornis in different stages of a Phaeocystis globosa bloom—a mesocosm study

Selective grazing of a calanoid copepod Temora longicornis was measured during different stages of a Phaeocystis globosa bloom, in order to reveal (1) if T. longicornis feeds on single cells and/or colonies of P. globosa in the presence of alternative food sources, (2) if copepod food selection changes during the initiation, maintenance, collapse and decay of a P. globosa bloom and (3) if P. globosa dominated food assemblage provides a good diet for copepod egg production. Our results show low but constant feeding on small colonies of P. globosa, irrespective of the type or concentration of alternative food sources. In contrast, feeding on single cells was never significant, and the total contribution of P. globosa to carbon ingestion of T. longicornis was minor. T. longicornis fed most actively on the decaying colonies, whereas during the peak of the bloom copepods selected against P. globosa. Mostly, T. longicornis fed unselectively on different food particles: before the bloom, the major part of the diet consisted of diatoms, whereas during and after the bloom copepod diet was dominated by dinoflagellates and ciliates. Egg production was highest during the decay of the bloom, coinciding with highest proportional ingestion of heterotrophic organisms, but was not seriously reduced even during the peak of the bloom. We conclude that P. globosa blooms should not threaten survival of copepod populations, but the population recruitment may depend on the type (and concentration) of the dominant heterotrophs present during the blooms. Due to relatively unselective grazing, the impact of T. longicornis to the initiation of a Phaeocystis bloom is considered small, although grazing on decaying colonies may contribute to the faster termination of a bloom.     

A key for the identification of the known larval stages of the Mediterranean Brachyura

Summary

Based on the accounts by various authors, an identification key has been constructed for the planktonic zoeae of the 70 species of Mediterranean Brachyura whose larvae are known. The key is based on primary (spines of the carapace, exopodite of the antenna, spines of telson forks) as well as secondary (setation of mouthparts, processes and spines on abdominal somites) morphological characteristics. It allows the identification of the zoeae of 64 species plus those of Liocarcinus genus (six species).     

A new species of Hemicyclops (Copepoda,Poecilostomatoida) from a dredged area in Tokyo Bay,Japan

A new species of poecilostomatoid copepod, Hemicyclops japonicus, is described from a dredged area in Tokyo Bay. The new species can be distinguished from its congeners by a combination of the setation of the first antenna, the segmentation of the antenna and the urosome, the length to width ratio of the caudal ramus and the shape of the genital segment and the labrum.     

Evolution of arboreal tunnelling by larvae of Aenetus (Lepidoptera: Hepialidae)

Abstract

Aspects of larval feeding and tunnelling were described for seven species of the wood-boring genus Aenetus. The species were studied in Australia, New Caledonia, and New Zealand. A sequential pattern of larval feeding involving transfer from a fungal based diet to callus tissue in live trees, previously known for A. virescens, was confirmed for A. cohici and inferred for A. dulcis and A. paradiseus. A specialised “transfer” morph linking the two feeding stages in A. virescens was also confirmed for A. cohici and two unidentified species. The wood-boring habit involved entry into the host above ground level and the construction of a tunnel which extends into and then down the stem. Tunnels were often located on the lower surface of leaning branches or stems. Tunnel entrances were open to the host surface, but overlain by a silk- /frass web. Bark and underlying tissue were removed from around the tunnel entrance and a callus growth resulted, which the larva consumed. The evolutionary history of arboreal tunnelling in the Hepialidae was investigated using biogeographic analysis of generic distribution. It is argued that evolution and variation in arboreal tunnelling resulted from specialised recombinations of generalised ancestral characters. It is suggested that the study of arboreal tunnelling can provide a source of useful characters for systematic analysis of phylogenetic relationships within Aenetus. The potential systematic value of tunnel characters is illustrated for A. virescens.     

The conservation requirements of an endangered hoverfly, Hammerschmidtia ferruginea (Diptera, Syrphidae) in the British Isles

The saprophagous larva of the endangered hoverfly, Hammerschmidtia ferruginea (Fallén, 1817) (Diptera, Syrphidae) develops in wet, decaying sap under the bark of dead trees and branches of aspen, Populus tremula L. (Saliaceae). However this breeding site is transient: wet decay builds up patchily over 1.5–2 years of the tree or branch dying and lasts for a further 1–3 years before the bark falls off. Between 1990 and 2006, H. ferruginea swung through a cycle of abundance when the number of localities where it was detected dropped from 13 to 5 and back to 8. Fluctuations in amounts of dead wood caused by winds and storms probably explain this population swing. When there are few dead trees and branches, H. ferruginea breeds in sap flows on live P. tremula trees and populations are maintained but at low levels. To prevent local extinctions during periods when fallen wood is scarce, breeding habitat can be supplemented by felling trees and branches. Fallen wood with wet decaying sap is also important as an assembly site for mate selection. Adult food plants include flowers of bird cherry Prunus padus, rowan Sorbus aucuparia and hawthorn Crategus monogyna. Adults were recorded dispersing up to 1 km but are probably able to move further than this.     

Mospicalanus schielae,a new genus and species of calanoid copepod (Crustacea: Spinocalanidae) from deep Antarctic water

A new genus and species,Mospicalanus schielae, collected at bathypelagic depth in the Antarctic Ocean, is described from female specimens and a stage V male. The new species is placed in the Spinecalanidae on account of the absence of fifth legs and leg 1 characteristics. It appears to be closely related toMimocalanus Farran. 1908, sharing apomorphic characters such as the lack of a rostrum, reductions of setal armament on the mouthparts, and absence of an outer spine on the first exopod segment of leg 1.Mospicalanus schielae can be distinguished from other spinocalanid genera by the setation of the antennary exopod, the maxillule, and the paecoxal endite of maxilla. Diagnostic characters of Spinocalanidae and Bathypontiidae are also discussed in order to clarify affiliation of genera tentatively assigned to the latter family. An updated key is given for the spinocalanid genera.     

Discovery of wood nesting by a subterranean halictine bee,Lasioglossum (Evylaeus) vulsum (Hymenoptera: Halictidae)

An unusual nesting substrate of a subterranean halictine bee, Lasioglossum (Evylaeus) vulsum (Vachal), was found at Mt Ishizuchi‐san, Ehime, Japan. Two nests were obtained from a decaying log in a display sign for a local restaurant. Brood cells, forming a cell cluster, were constructed in a wood hollow with rotted wood fibers pressed together. Nests in the decaying log show the same structural elements as those made in soil. This is the first report of wood nesting by subterranean halictine bees belonging to the subgenus Evylaeus.     

The giant mycoheterotrophic orchid Erythrorchis altissima is associated mainly with a divergent set of wood‐decaying fungi

The climbing orchid Erythrorchis altissima is the largest mycoheterotroph in the world. Although previous in vitro work suggests that E. altissima has a unique symbiosis with wood‐decaying fungi, little is known about how this giant orchid meets its carbon and nutrient demands exclusively via mycorrhizal fungi. In this study, the mycorrhizal fungi of E. altissima were molecularly identified using root samples from 26 individuals. Furthermore, in vitro symbiotic germination with five fungi and stable isotope compositions in five E. altissima at one site were examined. In total, 37 fungal operational taxonomic units (OTUs) belonging to nine orders in Basidiomycota were identified from the orchid roots. Most of the fungal OTUs were wood‐decaying fungi, but underground roots had ectomycorrhizal Russula. Two fungal isolates from mycorrhizal roots induced seed germination and subsequent seedling development in vitro. Measurement of carbon and nitrogen stable isotope abundances revealed that E. altissima is a full mycoheterotroph whose carbon originates mainly from wood‐decaying fungi. All of the results show that E. altissima is associated with a wide range of wood‐ and soil‐inhabiting fungi, the majority of which are wood‐decaying taxa. This generalist association enables E. altissima to access a large carbon pool in woody debris and has been key to the evolution of such a large mycoheterotroph.     

Antrodia gossypium,Phlebiopsis gigantea and Heterobasidion parviporum: in vitro growth and Norway spruce wood block decay

Polymerase chain reaction-amplified and sequenced isolates of Antrodia gossypium, Phlebiopsis gigantea and Heterobasidion parviporum from decaying Norway spruce wood blocks after three and six months, which exhibited linear growth, were investigated. P. gigantea strains showed the fastest growth, whereas A. gossypium growth was five times slower. The differences between the mean daily increment of A. gossypium and the other examined isolates (except Hp2) were statistically significant. There were also significant differences in wood decay between densities over time. These results were confirmed by the decay acceleration index (DAI) and decay activity index, which were positively correlated with wood density regardless of the fungus species. The registered P. gigantea strains (Rotstop and PG Suspension) exhibited a strong decomposition ability (28% after six months); the weight loss caused by A. gossypium after six months of decay (15.2%) was similar to the results of P. gigantea (GB) after just three months (13.2%). All tested H. parviporum isolates showed rather rapid growth and equally strong wood decay (20–25%) compared to those of P. gigantea. DAI showed that A. gossypium may significantly contribute to wood decomposition over time, particularly in less dense wood samples. The use of both saprotrophs as biological agents against root pathogens is discussed.     

Achilaophonte maxima gen.n., spec.n., a new taxon of the Laophontidae (Copepoda,harpacticoida) from the high Antartic (Weddell Sea)

Male and female of a new genus and species of the family Laophontidae, Archilaophonte maxima, are described. The specimen was found in the high Antartic (Weddell Sea) and apprears to be the most primitive genus up to now within the superfamily Laophontoidea as defined by Huys (1990). Based on its setation of legs and mouth parts, however, it can be placed unequivocally into the family Laophontidae. Archilaophonte maxima gen. n. shows close affinities to the laophontid genus Esola Edwards 1891. Both genera form a monophyletic group which is interpreted here as the first and most primitive offshot in the evolution of the Laophontidae. The synapomorphies of the former lineage are the shape of the protopodite of the P1 and shape and setation of the female P5.     

Acanthodiaptomus denticornis another omnivorous calanoid copepod: description of its mouth appendages and feeding experiments on animal prey

The mouthpart morphology of the freshwater calanoid copepod Acanthodiaptomus denticornis was examined with optical microscopy. The mouthparts have sharp teeth and stout appendages with clawlike setae, typical of omnivorous calanoid mouthpart morphology. Observation of the buccal aperture with Scanning Electron Microscopy shows a large opening permitting feeding on prey as large as Keratella cochlearis. These observations agree with our feeding experiments which show that A. denticornis feed on K. cochlearis.