Antarcturus bovinus n. sp., a new Weddell-Sea Isopod of the family arcturidae (Isopoda: Valvifera)

Summary Antarcturus bovinus n. sp. (Isopoda, Valvifera) is described from the Antarctic Peninsula and the western and southern Weddell-Sea. This species can easily be recognized by the absence of large spines, the spine armature of the dorsal surface characteristic of other species is lacking. Only A. antarcticus Bouvier, 1910, A. coppingeri Miers, 1881, A. granulosus Nordenstam, 1933 and A. lillei Tattersall, 1921 are similar, but A. bovinus n. sp. can be discerned from these by the presence of blunt supraocular spines.Abbreviations used in text and figures A 1,2 antenna 1,2 - Hy hypopharynx - Md mandible - Md left mandible - Mx 1,2 maxilla 1,2 - Mxp maxilliped - P 1-7 pereopods 1-7 - Plp 1-5 pleopods 1-5 - rMd right mandible - Urp uropod     

Mixoscyphus antarcticus gen. nov., sp. nov. (Cnidaria, Hydrozoa, Sertulariidae), the first truly endemic genus of Antarctic benthic hydroids

A genus and species of Antarctic benthic hydroids new to science, Mixoscyphus antarcticus gen. nov., sp. nov., is described and figured. Its systematic position amongst allied genera of the family Sertulariidae is discussed. The studied material originates from the South Shetland Islands area (West Antarctica), which was collected by several Spanish and US Antarctic expeditions. Mixoscyphus gen. nov. currently represents the only complete endemic genus of Antarctic benthic hydrozoans. A discussion of other genera of benthic hydroids that are largely endemic to the Antarctic is also provided.     

Serum chemistry and antibodies against pathogens in antarctic fur seals, Weddell seals, crabeater seals, and Ross seals

Information on health parameters, such as antibody prevalences and serum chemistry that can reveal exposure to pathogens, disease, and abnormal physiologic conditions, is scarce for Antarctic seal species. Serum samples from Antarctic fur seals (Arctocephalus gazella, n=88) from Bouvet?ya (2000-2001 and 2001-2002), and from Weddell seals (Leptonychotes weddellii, n=20), Ross seals (Ommatophoca rossii, n=20), and crabeater seals (Lobodon carcinophagus, n=9) from the pack-ice off Queen Maud Land, Antarctica (2001) were analyzed for enzyme activity, and concentrations of protein, metabolites, minerals, and cortisol. Adult Antarctic fur seal males had elevated levels of total protein (range 64-99 g/l) compared to adult females and pups (range 52-79 g/l). Antarctic fur seals had higher enzyme activities of creatine kinase, lactate dehydrogenase, and amylase, compared to Weddell, Ross, and crabeater seals. Antibodies against Brucella spp. were detected in Weddell seals (37%), Ross seals (5%), and crabeater seals (11%), but not in Antarctic fur seals. Antibodies against phocine herpesvirus 1 were detected in all species examined (Antarctic fur seals, 58%; Weddell seals, 100%; Ross seals, 15%; and crabeater seals, 44%). No antibodies against Trichinella spp., Toxoplasma, or phocine distemper virus (PDV) were detected (Antarctic fur seals were not tested for PDV antibodies). Antarctic seals are challenged by reduced sea ice and increasing temperatures due to climate change, and increased anthropogenic activity can introduce new pathogens to these vulnerable ecosystems and represent a threat for these animals. Our data provide a baseline for future monitoring of health parameters of these Antarctic seal species, for tracking the impact of environmental, climatic, and anthropogenic changes in Antarctica over time.     

New Asellota from the Antarctic deep sea (Crustacea, Isopoda, Asellota), with descriptions of two new genera

Two new genera, Reductosoma gen.n. (Desmosomatidae) and Desmostylis gen.n. (Desmosomatidae), and five new species are described from the Maud Rise and the Gunnerus Ridgc, Antarctica. Two new species of the Desmosomatidae (Eugerdellatinae and Desmosomatinae) are described: Reduetosoma gunnera gen. et sp.n. and Desmosoma hesslera sp.n.; one species of the Munnopsidae (Eurycopinae), Disconectes colernuni sp.n.; and two species of the Macrostylidae from the Antarctic deep sea, Desmostylis obscurus gen. et sp.n. and Macrostylis sarsi sp.n. Comments on the phylogeny and zoogeography are given.     

Some Antarctic Entoprocta with Notes on Morphology and Taxonomy in the Entoprocta in General

-Six entoprocts are reported and figured from the Antarctic Region, collected by the Swedish Antarctic Expedition 1901–1903. The species are: Barentsia discreta (Busk, 1886), Pedicellina cernua (Pallas, 1774), Loxosomella antarctica sp.n., Loxosomella murmanica (Nilus, 1909), Loxosomella compressa Nielsen & Ryland, 1961, subsp. antarctica ssp.n., and Loxosomella brachystipes sp.n. The original diagnosis by Robertson of the genus Myosoma is discussed on the basis of the muscle strands in the calyx and the stalk.     

Some remarks on the taxonomy of Antarctic Leuconidae (Cumacea: Crustacea) with a description of a new speciesLeucon intermedius n. sp.

The newly described speciesLeucon intermedius n. sp. differs from other knownLeucon species by an inconspicuous antennal notch and the presence of only a few teeth at the dorsomedian crest. The species most similar toLeucon intermedius areL. septemdentatus andL. inexcavatus from the Antarctic/Subantarctic Ocean. A Table is given to allow direct comparison of the characteristics of allLeucon species known from the Antarctic/Subantarctic, Ocean. Forty-one specimens ofLeucon intermedius n. sp. were collected at depths ranging from 109 to 791 m in the vicinity of the Amery Depression (Indian Sector) and near King George Island (South Shetland Islands). Problems in distinguishing the Antarctic/Subantarctic species of the genusEudorella are discussed. The shape of the antennal notch is suggested as a better characteristic to distinguish theEudorella species than the proportions of the articles of extremities. On the basis of this criterion, samples at the Zoological Museum, Hamburg are made up of two species ofEudorella: gracilior and cf.fallax.     

Three new species of Paralomis (Crustacea, Decapoda, Anomura, Lithodidae) from the Pacific and Antarctic Oceans

Three new species of the lithodid genus Paralomis from the Sulawesi (Celebes) Islands, P. ochthodes sp.n., Chilean coast, P. tuberipes sp.n., and Antarctic Ocean, P. birsteini sp.n., are described and illustrated. The first two species have features that set them well apart from other species of the genus. Characters are also given to distinguish P. birsteini from the closely allied P. spectabilis Hansen (North Atlantic).     

Mites of the genus Eupodes (Acari, Prostigmata) from maritime Antarctica: a biometrical and taxonomic study

A series of 40 male and 40 female mites of the prostigmatid genus Eupodes from the maritime Antarctic were each scored for 58 morphological characters, and principal co-ordinate analyses were performed on each data set. The analyses produced three clusters of points, which were interpreted as representing three species. One of these species, identified as Eupodes minutus (Strandtmann), the only species of Eupodes currently known from the maritime Antarctic, is redescribed. The other two species, E. exiguus up. and E. parvus nsp., are described. Two subspecies are recognized for the latter species, E. p. parvus from the South Orkney Islands, and E. p. grahamensis nsp. from the Antarctic Peninsula and South Shetland Islands. The geographical distribution and habitat preferences of the four text are discussed, and a key to the species is presented.     

Do bipolar distributions exist in marine sponges? Stylocordyla chupachups sp. nv. (Porifera: Hadromerida) from the Weddell Sea (Antarctic), previously reported as S. borealis (Lov��n, 1868)

Sponges are the dominant invertebrates in many Antarctic communities, where they play a decisive structural function thanks to their abundance and large sizes. However, current knowledge on Antarctic sponges remains poor even with respect to basic aspects such as taxonomy. Here, we report on an Antarctic species of the genus Stylocordyla, which has been recorded for a long time under the name of the boreal S. borealis due to spicule and growth habit similarities. A thorough study of dense populations of the only Stylocordyla species known up to now from the eastern zone of the Weddell Sea as well as the re-examination of several specimens (including the type material) of S. borealis has allowed us to assess the variability of the boreal species and to confirm that the austral species is not S. borealis (Lovén, 1868) but a new species of Stylocordyla, different from the other congeners recorded from southern latitudes. The new species S. chupachups commonly dwells on horizontal or slighted sloped hard bottoms of the continental shelf of Weddell Sea, from 100 m to below 400 m depth, although the densest populations usually occur between 150 and 300 m. It is a pioneer species in areas that have been scoured by icebergs, and thus its presence may be considered an indicator of recent colonisation.     

New species of plunderfish Pogonophryne favosa sp. n. (Artedidraconidae, Notothenioidei, Perciformes) from the Cosmonauts Sea (Antarctica) with description in artedidraconids of unusual anatomical structures-convexitas superaxillaris

A new species of plunderfish Pogonophryne favosa sp. n. from the mesobenthal of the Cosmonauts Sea, Antarctica, has been described. The new species belongs to a group of species “mentella”, differing from other species of the group in the presence of spots on the abdominal side of the body and a unique structure of mental barbel. An anatomohistological study was performed of convexitas superaxillaris—unusual skin formations first found in Artedidraconidae. Their possible function in the system of cold resistance of Antarctic Notothenioidei and possible historic dates of their appearance in the family Artedidraconidae are discussed.     

Shallow-water benthic hydroids from Tethys Bay (Terra Nova Bay, Ross Sea, Antarctica)

The shallow-water hydrozoan Antarctic fauna is still poorly studied, and available knowledge mostly refers to samples gathered by traditional ship-operated gears. By scuba diving in the coastal areas off the Italian Antarctic station “Mario Zucchelli” (Ross Sea, Terra Nova Bay), in the austral summer 2002–2003, a total of 20 hydrozoan species were found, belonging to 10 families and 13 genera. As hypothesized, Anthoathecata (11 species), usually under-represented in collections from indirect sampling gears, are common as also are Leptothecata (9 species). Hydractiniidae and Hydractinia are the dominant family and genus, followed by Haleciidae and Halecium. A new species to science, Halecium exaggeratum sp. nov. is also described. Most species are either endemic to Antarctic waters or restricted to Antarctic/sub-Antarctic areas; only two species have a wider distribution. Material reared in aquaria at the Italian Antarctic Base Mario Zucchelli facilitated knowledge of the life cycle and reproductive biology of several species. In particular, Opercularella belgicae was found to liberate a medusa stage referable to Phialella, and the species is assigned here to that genus, as Phialella belgicae. Also, extraordinary is the complete absence or scant representation of the most typical Antarctic benthic hydroid genera (Antarctoscyphus, Oswaldella, Schizotricha, Staurotheca, and Symplectoscyphus), likely related to the shallow limits of sampling (down to 48 m).     

Marine Tubificidae (Oligochaeta) of Antarctica, with descriptions of three new species of Phallodrilinae

Five species of Tubificidae are recorded from Antarctic waters: Torodrilus lowryi Cook, 1970, Torodrilus sp. (subfamily Rhyacodrilinae), Marionidrilus antarcticus sp. n., M. weddellensis sp. n., and Thalassodrilus bicki sp. n. (subfamily Phallodrilinae); only T. lowryi was known from Antarctica before. The status of the two Southern Hemisphere genera Torodrilus Cook, 1970, and Marionidrilus Erséus, 1992, are discussed; although the taxonomic position of the two new species of Marionidrilus is somewhat uncertain. Thalassodrilus bicki , however, appears closely related to Northern Hemisphere taxa.     

Systematic notes on some Antarctic Ascophora (Bryozoa, Cheilostomata)

Nine new species of ascophoran cheilostome Bryozoa are described from Antarctic localities. Five species are considered to be new to science ( Smittina favulosa, Smittina diffidentia, Smittoidea pugiuncula, Escharella mamillata, Fenestrulina antarctica ), while four others have been previously recorded under other names ( Smittoidea malleata, Escharella watersi, Lacerna watersi, Hippothoa belgica ). Escharella crozetensis Waters, formerly recorded from Antarctica, is considered to be limited to the Kerguelen region of the South Indian Ocean.     

Introduction. Antarctic ecology: from genes to ecosystems. Part 2. Evolution, diversity and functional ecology

The Antarctic biota has evolved over the last 100 million years in increasingly isolated and cold conditions. As a result, Antarctic species, from micro-organisms to vertebrates, have adapted to life at extremely low temperatures, including changes in the genome, physiology and ecological traits such as life history. Coupled with cycles of glaciation that have promoted speciation in the Antarctic, this has led to a unique biota in terms of biogeography, patterns of species distribution and endemism. Specialization in the Antarctic biota has led to trade-offs in many ecologically important functions and Antarctic species may have a limited capacity to adapt to present climate change. These include the direct effects of changes in environmental parameters and indirect effects of increased competition and predation resulting from altered life histories of Antarctic species and the impacts of invasive species. Ultimately, climate change may alter the responses of Antarctic ecosystems to harvesting from humans. The unique adaptations of Antarctic species mean that they provide unique models of molecular evolution in natural populations. The simplicity of Antarctic communities, especially from terrestrial systems, makes them ideal to investigate the ecological implications of climate change, which are difficult to identify in more complex systems.     

Benthic hydroids (Cnidaria: Hydrozoa) from the Bransfield Strait area (Antarctica) collected by Brazilian expeditions,with the description of a new species

A total of 36 species of benthic hydroids, belonging to nine families and 16 genera, were found in the hydroid collection gathered during the Brazilian Antarctic expeditions PROANTAR III and IV. Seven of the species were identified only to generic level. There is a clear dominance of the subclass Leptothecatae with 33 species. By far the most diversified family was the Sertulariidae, with 16 species (44%). Symplectoscyphus with eight species, including Symplectoscyphus magnificus sp. nov., is the most diversified genus. Almost 70% of the species diversity is restricted to just six genera (38%). Sixty-eight percent of the species is Antarctic endemics and 86% is restricted to Antarctic or Antarctic/sub-Antarctic waters. Eudendrium antarcticum and Amphisbetia operculata are recorded for the first time from Antarctic waters.     

New Antarctic holothurians (Echinodermata) – I. Five new species with four new genera of the order Dendrochirotida

Five new Antarctic species and four new genera of dendrochirote holothurians are described: Caespitugo diversipes gen. et sp.n., Caespitugo citriformis gen. et sp.n., Microchoerus splendidus gen. et sp.n. (all Cucumariidae), Crucella hystirix gen. et sp.n. (Paracucumidae), and Echinopsolus acanthocola gen. et sp.n. (Psolidae). To include Crucella in the Paracucumidae a minor change of the family diagnosis was necessary. This change is discussed. The species were caught on the continental shelf of the southern and eastern Weddell Sea. mainly in depths between 200 and 650m. Their systematic status within their families as well as relationships to representatives of other familes are discussed.     

Snow algae of the Windmill Islands,continental Antarctica. 2. Chloromonas rubroleosa sp. nov. (Volvocales,Chlorophyta), an alga of red snow

A new, cryophilic species of the Chlamydomonadaceae, Chloromonas rubroleosa, is described from continental Antarctica. The species is characterised by a bimamillate papilla, four contractile vacuoles, numerous small discoid chloroplasts and an abundance of red-pigmented oil droplets. The local distribution of the species and its habitat conditions are described. The cells are susceptible to temperatures above 10°C and, unexpectedly, to subfreezing temperatures. The species has been isolated into pure culture and is currently maintained at the Australian Antarctic Division.     

<Emphasis Type="Italic">Rhinoglena kutikovae</Emphasis> n.sp. (Rotifera: Monogononta: Epiphanidae) from the Bunger Hills,East Antarctica: a probable relict species that survived Quaternary glaciations on the continent

A new species of rotifer, Rhinoglena kutikovae n.sp. (Monogononta: Epiphanidae), is described from a freshwater lake in the Bunger Hills, East Antarctica. The new taxon is characterized by the following combination of characters: body conical to vase-shaped; a single toe; distal foot pseudosegment bulged; tail prominent, semi-circular; two small spherical pedal glands with common duct, forming a complex with caudal ganglion; trophi with seven major teeth with offset head and two smaller teeth without offset head. The new species is compared with R. fertoeensis, R. frontalis and R. tokioensis, of which scanning electron microscopic information is presented of the trophi. R. kutikovae n.sp. is probably a relict species that survived Quaternary glaciations in glacial lacustrine refugia on the Antarctic continent.