Food resource partitioning among Arctic sublittoral lysianassoid amphipods in summer

Five species of lysianassoid amphipods (Anonyx nugax, Anonyx sarsi, Onisimus caricus, Onisimus edwardsii, Orchomenella minuta) co-occur in the shallow sublittoral of Kongsfjorden (Svalbard, Arctic), share similar functional attributes, and exploit a common food base. All species are known to be necrophagous; however, this study revealed through combination of gut-content analysis with the morphological characteristics of their mandibles and available information on feeding ecology, the complexity of their trophic strategies. Only mature individuals of A. nugax are true scavengers; immature individuals of this species feed on both animal and non-animal food. A. sarsi and O. caricus are scavengers and predators; the former prefers polychaetes, while the latter relies mostly on zooplankton. O. edwardsii is an omnivorous feeder, and the set of its primary food consists of carrion, crustaceans, and algae. O. minuta is a detrivorous–carnivorous species. These results indicate that niche overlap among these closely related species is reduced, not only by spatial segregation, but also by the exploitation of different components of food resources.     

The taxonomic status of Hylopsis platycephalus Werner, 1894 and Centrolenella Noble, 1920 (Amphibia: Anura)

On the assumption that the holotype of the South American frog Hylopsis platycephalus, described by Franz Werner in 1894, had been lost, Lynch (1981) designated a neotype, but in so doing incorrectly associated a centrolenid species with that name. As a result of the neotype designation, the genus Centrolenella Noble, 1920 (Centrolenidae) became a junior subjective synonym of Hylopsis Werner, 1894.
The holotype of Hylopsis platycephalus, which has never been lost, was obtained from the Institut fur Zoologie der Universität Wien and on examination was found to be a species of Sphaenorhynchus Tschudi, 1838 (Hylidae) distinct from other known members of the genus. Centrolenella Noble is thus validated and Hylopsis (ayn. nov.) becomes a junior subjective synonym of Sphaenorhynchus.
The rules of nomenclature relating to the neotype are discussed and Sphaenorhynchus platycephalus comb. nov. is redescribed. The centrolenid species which Lynch (1981) assigned to Hylopsis platycephalus is named Centrolenella savagei sp. nov.     

Benthic scavengers collected by baited traps in the high Arctic

Baited traps were deployed in the coastal areas of Svalbard (0–175 m), Franz Josef Land (15 and 20 m), Northeast Greenland (6 and 20 m) and Ellesmere Island (2–145 m). The samples were dominated by Lysianassidae (Amphipoda). In the most extensively sampled locality (Hornsund, Svalbard), differences between the necrophagic fauna of the outer and inner basins were observed. Clear depth separations of closely related species of the Anonyx and Onisimus genera were found between 0 and 175 m in Hornsund. Anonyx nugax and Onisimus edwardsi were the only species found in all of the examined localities. Accepted: 14 January 2000     

Seasonal changes in organic composition and caloric content of an Arctic marine amphipod, Onisimus (= Boeckosimus) affinis H.J. Hansen

Protein, lipid, carbohydrate, chitin, ash, and caloric energy contents of the Arctic marine benthic amphipod Onisimus (= Boeckosimus) affinis H.J. Hansen were determined at intervals over two and one half years. The lipid content exhibited the most pronounced seasonal change, from a minimum of about 14–17% of dry wt to a maximum of 25–27% of dry wt. An increase in lipid content in the spring coincided with the reproductive period of the species. Lipid and caloric content decreased during the summer to levels that were maintained through the winter, indicating that the animals do not store significant nutritional reserves for use during the winter. The dry weight proportions of other components were: protein 27.7–38.3%; carbohydrate 1.8–4.0%; chitin 7.8–8.2%; ash 21.3–27.2%. Caloric content varied between 3.29 and 4.18 cal/mg dry wt.     

Towards a revision of Ameira Boeck, 1865 (Harpacticoida, Ameiridae): reinstatement of Psammameira Noodt, 1952

Both sexes of Ameira hyalina (Noodt, 1952) and A. parasimulans Lang, 1965 are redescribed. The genus Psammameira Noodt, 1952 previously regarded as a junior subjective synonym of Ameira. is reinstated to accommodate these two species and a revised diagnosis for the genus is presented. Examination of the type material of Psammameira reducta Wells, 1967 and P. gradis (Nicholls, 1939) revealed that they should be removed from the genus. The possible relationships of two species of doubtful affinity, A. esigun T. Scott, 1894 and A. simulans T. Scott, 1912 are reconsidered. The phylogenetic position of Psammameira within the Ameiridae is briefly discussed.     

Chemoreception in an arctic amphipod crustacean: A field study

Traps baited with meat or fish were set through the ice in 5 m of water near Prudhoe Bay, Alaska. They were monitored by divers and surface observers. Over 99% of the animals attracted to the bait were the lysianassid amphipod Boeckosimus (= Onisimus) affinis (Hansen). Up to 20000 individuals were collected during each 24-h trapping period. Animals moved to the trap only from a downcurrent direction, and from a distance of up to at least 30 m away. It is suggested that chemoreception is the method used to find bait: animals swam into the current after receiving the stimulus and required a constant presence of stimulus at some threshold level to continue moving to the bait.     

Salinity tolerance and osmoregulation of the arctic marine amphipods Onisimus litoralis (Kroyer) and Anonyx nugax (Phipps)

Summary The gammarid amphipod Onisimus litoralis, which inhabits arctic and subarctic intertidal and under-ice habitats, is a euryhaline hyperosmotic regulator. It survives 10 d exposures to salinities from 5 to 55 ppt. It hyperregulates its hemolymph osmolality during 3 h exposures to dilutions of 33 ppt seawater and remains hyperosmotic for at least 2 w. The hemolymph is isosmotic to the medium after 12 h exposures to salinities higher than 33 ppt. The gammarid amphipod Anonyx nugax, which inhabits arctic and subarctic subtidal areas, tolerates salinities from 23 to 45 ppt with little mortality. Unlike Onisimus, however, it is an osmoconformer and its hemolymph becomes isosmotic to all dilute salinities within its tolerance range after 12 h and to concentrated media after 3 h. The salinity tolerances and osmoregulatory abilities of both species are reflected in their distributions in the field.     

Deep-sea asellote isopods of the north-east Atlantic: the family Thambematidae

A collection of thambematids (Crustacea, Isopoda, Asellota) from depths of 1400–2900 m in the Rockall Trough, west of the British Isles, is considered. The type species of the genus Thambema Stebbing, T. amicorum Stebbing, is rediagnosed and three new species, T. golanachum, T. tanum , and T. fiatum , are described. The genera Thambema and Microthambema Birstein are contrasted and taxonomic characters separating these genera are provided. The difficulty of providing effective definitions for higher category taxa is discussed and a new definition is provided for the Asellota.     

Response of oxidative stress parameters and sunscreening compounds in Arctic amphipods during experimental exposure to maximal natural UVB radiation

The paper investigates tolerance to UV radiation (UVR) in 3 amphipod species from the Arctic Kongsfjord, Spitsbergen: the herbivore Gammarellus homari (0- to 5-m water depth), the strictly carnivore scavenger Anonyx nugax (2- to 5-m water depth) and the detritivore/carnivore Onisimus edwardsi (2- to 5-m water depth). In previous radiation exposure experiments, both carnivore species displayed elevated mortality rates already at moderate UVR levels. Therefore, the concentrations of sunscreening compounds (mycosporine-like amino acids, MAAs, and carotenoids) and two antioxidant enzymes (superoxide dismutase, catalase) were studied in the animals under control conditions and following moderate as well as high UVR exposure.In both carnivore amphipods elevated sensitivity to experimental UVR exposure went along with a degradation of the tissue carotenoid and MAAs and a decrease of the enzymatic antioxidant defence, which resulted in increased lipid peroxidation in exposed animals. In contrast, the herbivore G. homari seems well protected by high concentrations of MAAs absorbed from its algal diet, and no oxidative stress occurred under experimental UVR. The species-specific degree of UV tolerance correlates well with the animals' typical vertical distribution in the water column.     

Hemibranchiate sphaeromatids (Crustacea: Isopoda) from Queensland, Australia, with a world-wide review of the genera discussed

All known Queensland species of the isopod family Sphaeromatidae, subfamily Sphaeromatinae (= hemibranchs), are discussed. The following new taxa are erected: Calcipila cornuta, gen. nov., sp. nov. ; Cymodoce tribullis, sp. nov. ; Cymodoce bipapilla, sp. nov. ; Paracilicaea aspera, sp. nov. ; Cilicaeopsis glebosa, sp. nov. ; Cilicaeopsis furculata, sp. nov. ; Cilicaea calcarifera, sp. nov. ; Zuzara curtispina, sp. nov. ; Zuzara digitata, sp. nov. ; and Clianella brucei, sp. nov. Exosphaeroma intermedium Baker is transferred to the genus Sphaeroma Latreille. The genus Dynoides Barnard is reviewed and its current synonymy is contested. With several new records, this brings the total number of sphaeromatid species known from Queensland to 49, 24 of which are in the subfamily Sphaeromatinae. A checklist of all sphaeromatid species occurring in Queensland waters is given. From the rest of Australia: Cymodoce tuberculata Haswell is given the replacement name Cymodoce haswelli, nom. nov. ; Cymodoce granulata Miers is made a junior synonym of Cerceis trispinosa (Haswell) (subfamily Dynameninae); Zuzara diadema Leach, Z. dicantha (Milne Edwards) and Z. Integra Haswell are made junior synonyms of Z. semipunctata Leach; Cilicaeopsis dakini Tattersall is tentatively transferred to the genus Paracilicaea Stebbing. The genera discussed are reviewed world-wide and among the non-Australian species: Exosphaeroma papillae Bayliff is transferred to the genus Sphaeroma; Sphaeroma irakiensis Ahmed is made a junior synonym of Sphaeroma annandalei annandalei Stebbing; Cymodoce richardsoniae Nobili is shown to be distinct from Cymodoce truncata Leach; Cymodoce eupyga Nobili is transferred to the genus Paracilicaea; Dynoides amblysinus Pillai, Dynoides castroi Loyola e Silva and Exosphaeroma globicaudum (Dana) are transferred to the genus Clianella Boone; Dynoides brasiliensis (Loyola e Silva; and Sphaeroma savignn Milne Edwards sensu Dana, 1853 are declared to be conspecific with Clianella castroi. The name Sorrentosphaera Verhoeff is made a junior synonym of Dynamene Leach (subfamily Dynameninae.     

New data on the systematics of leaf-beetle genus Chrysolina (Coleoptera, Chrysomelinae) from the Palaearctic region

Chrysolina przewalskii (Jacobson, 1895) and Ch. lucidula Chen, 1934 are redescribed based on the type specimens. Neotype of Ch. przewalskii is designated. Ch. daccordii Lopatin, 2000 is a new junior synonym of Ch. juldusana (Lopatin, 1962); Ch. daosana Lopatin, 2007 is a new junior synonym of Ch. tani Lopatin, 1998; Ch. burchana Lopatin, 1998 is a new junior synonym of Ch. przewalskii (Jacobson, 1895). Ch. lucidula Chen, 1934 described from a mislabeled specimen is a new junior synonym of the South European Ch. lucida (Olivier, 1807). Ch. hyrcana var. cyanescens (Jacobson, 1894) is synonymized with Ch. circumducta (Ménétriés, 1848) and is merely a color form of the latter species.     

Revision of the fossil cylindrotomidae (Diptera,Nematocera) from florissant and White River,USA

Fossil species of the genusCyttaromyia Scudder (Diphtera, Cylindrotomidae) described by Scudder in 1877 and 1894 from the Eocene of White River Basin and the Lower Oligocène of Florissant, Colorado, are revised.Cyttaromyia fenestrata Scudder from White River andCyttaromyia princetoniana Scudder are redescribed; the remaining species: C.cancellata Scudder, C.clathrata Scudder and C.oligocena Scudder are regarded as junior synonyms of C.princetoniana.     

SYSTEMATICS OF THE CAMBRIAN TRILOBITE FAMILY NEPEIDAE, WITH REVISION OF AUSTRALIAN SPECIES

Abstract:  Taxonomy of the Cambrian trilobite family Nepeidae is revised. Morphometric analyses of the genera Nepea and Penarosa demonstrate that use of proportions of linear dimensions of the cranidium to differentiate species is invalid, and that infrageneric variation is continuous. The taxonomy and biostratigraphy of all Australian species of Nepeidae is revised. Species considered valid herein include: Nepea narinosa (type species), N. tonsillata , N. nans , Penarosa retifera (type species), P. elaticeps , P. rhinodelphis , P. netenta , Loxonepea loxophrys (type species) and Ferenepea hispida (type species). Folliceps is considered to be a junior subjective synonym of Nepea , Trinepea is regarded as a junior subjective synonym of Penarosa , and Ascionepea is considered to be a junior subjective synonym of Ferenepea .     

On the Three Enigmatic Species of <Emphasis Type="Italic">Acmaeodera</Emphasis> Eschscholtz from India and Pakistan in the Collection of Forest Research Institute in Dehradun (Coleoptera,Buprestidae: Polycestinae)

The taxonomic position of three enigmatic buprestid species: Acmaeodera kerremansi Stebbing, A. beesoni Obenberger, and A. gardneri Obenberger described from the “Upper Punjab” is discussed. Examination of the high resolution images of the type specimens of these species deposited in the National Forest Insect Collection (Forest Research Institute, Dehradun, India) has proved that all of them belong to the subgenus Lisposcelis Volkovitsh. Lectotype is designated for A. kerremansi. The putative synonymy of some recently described Indian acmaeoderine taxa is discussed. A list of all the known species of the subgenus Lisposcelis is provided.     

中国竹飞虱属分类研究(半翅目,蜡蝉总科,飞虱科)

整理记述中国飞虱科竹飞虱属Bambusiphaga Huang et Ding 14种.研究发现丁锦华、黄其林(1979)对该属模式种黑斑竹飞虱B.nigripunctata雄性外生殖器阳茎结构的图示与王金川、丁锦华(1996)在<甘肃飞虱>中对该种阳茎结构的记述及图示不同,通过解剖西北农林科技大学昆虫?骀 博物馆馆藏的该种标本,发现其阳茎结构与王金川、丁锦华(1996)记述及图示的阳茎结构相同,在检查了该种的模式标本后,确认丁锦华、黄其林(1979)图示的雄性外生殖器阳茎结构并非本种.本文对该种雄性外生殖器结构作了重新描记,并绘制了该种成虫及雄性外生殖器鉴别特征图.文中还建立1个新组合:B.bakeri(Muir)nov.comb.及2个新异名:B.membranacea Yang et Yang,1986为B.furca Huang et Ding,1979的异名;B.latispina Qin et Yuan,1999为B.bakeri(Muir,1919)的异名.文中还提供了该属所有中国种类的检索表.     

论奥陶纪三叶虫属Reedocalymene Kobayashi, 1951

由于建立Ｒｅｅｄｏｃａｌｙｍｅｎｅ一属的模式种标本保存甚差,长期以来,这一属的概念一直不甚明了,研究了峡东地区庙坡组新发现的丰富日保存完好的Ｒｅｅｄｏｃａｌｙｍｅｎｅ ｅｘｐａｎｓａ Ｙｉ材料,其中完整背过 首次发现。新材料揭示了以往Ｒｅｅｄｏｃａｌｙｍｅｎｅ的一些鲜为人知的背面和腹面形态,从而有可能对该属进行全面的修订,讨论了Ｒ．ｅｘ－ｐａｎｓａ的某些重要特征,如面线、前坑、腹边缘板、前舌以及壳     

Neoaplectana Steiner, 1929 a junior synonym of Steinernema Travassos, 1927 (Nematoda; Rhabditida)

Summary A type specimen of Steinernema kraussei and a population of this nematode from the type host were compared with three species of Neoaplectana. No characters were found to separate the two genera and so Neoplectana Steiner, 1929 is considered to be a junior synonym of Steinernema Travassos, 1927. Valid species now included within the genus Steinernema are: S. kraussei (Steiner, 1923) Travassos, 1927 (type species); S. glaseri (Steiner, 1929) n.comb.; S. feltiae (Filipjev, 1934) n.comb. and S. bibionis (Bovien, 1937) n.comb. A key is given to these four species and their junior synonyms are listed.     

Revision of the type species of Sigalion, Thalenessa and Eusigalion (Polychaeta: Sigalionidae)

The type species of Sigalion Audouin & Milne Edwards, 1830 (5. mathildae), Thalenessa Baird, 1866 (S. edwardsi Kinberg, 1856) and Eusigalion Augener, 1918 (E. vazensis) are re-examined. Since they were first described all three genera have been variously misrepresented, but are currently distinguished by the presence (Thalenessa; syn. Eusigalion) or absence (Sigalion) of a median antenna. Material examined in the present study indicates that S. mathildae also possesses a median antenna. Thalenessa and Eusigalion are considered to be junior synonyms of Sigalion and the generic placings of all species attributed to these genera are investigated.