A new species of Ingolfiellidae (Peracarida, Amphipoda, Crustacea) from the Azores, Portugal

A new species of Ingolfiellid Amphipod Ingolfiella azorensis n. sp. is described from samples collected in a benthic survey off the Azores archipelago, Portugal. The new species is characterized by the lack of ocular lobes, a four-toothed dactylus on the first and second gnathopods, and having dissimilar claws on the third to seventh pereiopods. Individuals were obtained from shallow subtidal samples of sand. The new findings bring the number of Ingolfiellidae from Macaronesia up to six, equalling almost 20 % of the world’s known species, suggesting this area as a potential evolutionary centre for Ingolfiellidae.     

Burrowing,grooming, and feeding behaviour of Paraceradocus,an antarctic amphipod genus (Crustacea)

Summary Species of the amphipod genus Paraceradocus found near the Antarctic Peninsula were observed in aquaria. The animals live under stones in burrows in sediment which they excavate with their gnathopods. During burrowing the animal regularly turns backwards in a somersault-like movement. Paraceradocus feeds on detritus, which is manipulated by the gnathopods and the antennes. The gnathopods are also used for grooming. A dense brush of setae at the medial surface of the carpi of the gnathopods I is used to clean off fine particles from the antennes. These particles are transferred to the maxillipeds and are ingested. The rear appendages are mainly cleaned by the gnathopods II. Young animals sitting between the gnathopods of the adult participate in feeding.     

A new marine interstitial Psammogammarus (Crustacea, Amphipoda, Melitidae) from Gura Ici Island, off western Halmahera (North Moluccas, Indonesia), and an overview of the genus

Psammogammarus wallaceisp. n. is described from the shallow marine interstitial of a sand and coral rubble beach on the Gura Ici islands (North Moluccas; Indonesia). This is the first record of this circum-tropical genus from SE Asia, with the geographically closest relative inhabiting the Ryukyu archipelago in Japan. The new species is highly distinctive by the display of sexual dimorphism on pleopod II, with the medial margin of the male proximal article of exopod provided with a comb of short, blunt curved spinules; no other representative of the genus is known to display sexually-dimorphic appendages aside of the gnathopods. The new species is also noteworthy by the outline of the palm margin of male gnathopod II, hardly excavated, and by showing a carpus broader than long. An overview of the genus Psammogammarus with 14 species to date is provided.     

Two new species of Urothoe (Crustacea, Amphipoda, Gammaridea) from the East Johor Islands Archipelago, Malaysia

Two new species of urothoid amphipods from Pulau Sibu and Pulau Tinggi, Johor are described and illustrated. The specimens of Urothoe sibuensis new species were collected by vertical haul plankton net and is distinctively different from other existing Urothoe species by these combination of special characters; similar gnathopods 1-2 with short and stout propodus expanded into poorly defined palms; large eyes and epimeron 3 smooth. Urothoe tinggiensis new species as collected using an airlift suction sampler at seagrass area is characterized by its different gnathopodal configuration with setose dactylus of 5th pereopod; eyes minute; carpus is wider than merus in the 5th pereopod; subquadrate coxa 4; merus and carpus of pereopods 6-7 are linear.     

Cleansing mechanisms of caprellid amphipods (Crustacea) from North America

There are three cleaning mechanisms utilized by intact caprellids separable by the body region being cleansed: antennae, mouthparts, and the remainder of the body. Antennal cleansing is a function of the first gnathopods and maxill'ipeds, mouthpart cleaning utilizes all of the mouthparts, and body cleansing relies solely on the first gnathopods. Behaviorally, filter feeders groom and feed approximately as much as predators, but filter feeders cleanse their entire body whereas predators primarily cleanse only both pair of antenna. The possibility that filter feeding was evolutionarily derived from cleaning activities is proposed.     

An assessment of Putative Sexually Antagonistic Traits in a Freshwater Amphipod Species

Sexual conflict can result in an ‘evolutionary arms race’ between males and females, with the evolution of sexual antagonistic traits used to resolve the conflict in favor of one sex over the other. We assessed the resolution of sexual conflict in a Hyalella amphipod species by manipulating putative sexually antagonistic traits in males and females and used mate‐guarding duration as our metric of conflict resolution. We discovered that large male posterior gnathopod size increased mate‐guarding duration, which suggests that it is a sexually antagonistic trait in this species. In contrast, female and male body size did not significantly affect mate‐guarding duration. Given that male posterior gnathopods show heightened condition dependence, future investigations should explore the interactive effects of sexual conflict and ecological context on trait evolution, phenotypic divergence, and speciation to elucidate the complex mechanisms involved in the evolution of biological diversity.     

Biomechanics and energy cost of the amphipod Corophium volutator filter-pump

The integrated function of the setal filter-basket and the pleopodal pump in the burrowing amphipod Corophium volutator was studied by video-microscopy in order to evaluate the energy costs of filter feeding. Video-microscope observations indicated that, in general, nine short, water-pumping beat cycles of the pleopods are succeeded by one slow cycle that coincides with cleaning of the setal filter and transient slowdown of inhalant water velocity. The position of the plumose setal filter on the second pair of gnathopods ensures that all water runs through the filter-basket. The fine V-shaped bristles on the setae enlarge the total filter area so that the velocity of water flowing through the filter is relatively slow, about 2.5 mm s(-1), giving rise to a resistance of about 2.9 mm H(2)O, which is the most important contribution to the total pressure drop in the system. In "standard" individuals of C. volutator with lengths of 3 and 6 mm, the normal operating pump pressure and pumping rate were, respectively, 2.6 and 3.1 mm H(2)O, and 18.3 and 85.5 ml h(-1); the overall pump efficiencies were 5.1% and 11.6%, respectively. These results show that the Corophium filter-pump is comparable to other low-pressure biological pumps in filter-feeding marine invertebrates, such as mussels, polychaetes, ascidians, and bryozoans.     

Paradollfusnema telfordi n. sp. (Nematoda: Cosmocercidae) from the worm lizard,Rhineura floridana (Amphisbaenia), of Florida

Paradollfusnema telfordi n. sp. (Nematoda: Cosmocercidae) from the large intestine of a worm lizard, Rhineura floridana, collected in Florida is described and illustrated. Paradollfusnema telfordi n. sp. represents the second species assigned to the genus and is distinguished from the other species on the basis of caudal papillae patterns in the male: P. telfordi n. sp. with 8 pairs of precloacal papillae, second pair from anterior much larger than others; Paradollfusnema amphisbaenia with 4 or 5 pairs of precloacal papillae, all of equal size.     

A new species of Ditrachybothridium (Cestoda: Diphyllidea) from Galeus sp. (Selachii, Scyliorhynidae) from the south Pacific Ocean, with a revision of the diagnosis of the order, family, and genus and notes on descriptive terminology of microtriches

Ditrachybothridium piliformis is a new species from the spiral intestine of a cat shark, Galeus sp., from the southern Pacific Ocean. This is only the second species assigned to Ditrachybothridium. It differs from the type species D. macrocephalum in lacking spines on the scolex, a character originally used to diagnose the genus. The diagnoses of the Ditrachybothridiidae and of Ditrachybothridium have been revised to reflect this difference. This new species is further differentiated from the type species in its possession of pectinate spinitriches on the tegument of the scolex. The holdfast structures of this species are weakly muscularized, with no membrane-bound layer of radial muscles, indicating that the holdfast structures are bothria rather than bothridia as described in the most recent literature. Several reports for other species have indicated the same situation in other diphyllideans. The diagnosis of the order has been revised to reflect this finding.     

Direct and indirect fitness consequences of female choice in a crustacean

Understanding the evolution and maintenance of female mate choice requires information on both the benefits (the sum of direct and indirect benefits) and costs of selective mating. In this study, I assessed the fitness consequences of female mate choice in a freshwater crustacean. In Hyalella amphipods, males attempt to form precopulatory pairs with females. Large males, bearing large posterior gnathopods, tend to be over-represented in precopulatory pairs. I show that females receive both direct (reduced risk of predation while paired) and indirect (sexy sons) benefits from mating with these males. Furthermore, the behavioral mechanisms used to filter male phenotypes carry no detectable energetic cost for females. Thus, females that choose males with successful phenotypes are expected to have higher Darwinian fitness than females that mate at random. This study shows that direct and indirect selection act together to favor large male size, which explains the sexual size dimorphism and size-based mating biases observed in this species.     

Tantulocarida (Crustacea) from the Southern Ocean deep sea,and the description of three new species of <Emphasis Type="Italic">Tantulacus</Emphasis> Huys,Andersen &; Kristensen, 1992

During the expedition ANT XIX/3 meiofauna samples were collected from the German research vessel Polarstern near the Shackleton Fracture Zone. During sorting of the samples 86 tantulus larvae were found. Extensive examination of the larvae revealed a high diversity of tantulocaridans in the Southern Ocean deep sea (33 species). A remarkable proportion of these were new species of Tantulacus Huys, Andersen & Kristensen, 1992. The present paper reports the discovery of three new Antarctic tantulocarids which are referred to Tantulacus. The affiliation of T. longispinosus n. sp., T. karolae n. sp. and T. dieteri n. sp. to Tantulacus is straightforward: all representatives of the Tantulocarida are characterised by the presence of 1-2 slender setae on the endopod of the second to fifth thoracopods, but in none of the hitherto described genera, other than Tantulacus, are these elements modified. Tantulacus hoegi Huys, Andersen & Kristensen, 1992 and the three new species share the possession of a distal rigid spine on the endopod of the second to fifth thoracopods as a synapomorphy and thus can be readily distinguished from other tantulocaridans. This is the first record of free-living sediment-inhabiting tantulus larvae from this area, although this probably reflects the degree of undersampling.     

Allatotropin, leucokinin and AKH in honey bees and other Hymenoptera

In the honey bee no allatotropin gene has been found, even though allatotropin stimulates the synthesis of juvenile hormone in this species. We report here that honey bees and other Hymenoptera do have a typical allatotropin gene, although the peptides predicted have a somewhat different structure from that of other insect allatotropins. Polyclonal antisera to honey bee allatotropin reacted with material in the neurohemal organs of the segmental nerves of abdominal ganglia. We were unable to find the allatotropin peptide using mass spectrometry in extracts from these tissues. Thus the expression of this gene in honey bees is less important than in other insect species. We also characterized the leucokinin gene which similarly appears to be very weakly expressed in worker honey bees. Unlike the allatotropin gene, which is conserved within Hymenoptera, the leucokinin gene is much more variable in structure and was not found in ants nor the parasitic wasp Nasonia vitripennis. The absence of significant expression of adipokinetic hormone (AKH) in the honey bee may be due to the existence of a second TATA box in the promotor region of the gene, which explains the production of an mRNA encoding a putative peptide precursor from which no AKH should be released. Such a second TATA box was not found in other Hymenoptera, and may therefore be specific for the two Apis species. It is suggested that functional disintegration of this important metabolic gene became possible in Apis because of the highly evolved social nature of the species.     

PETAURALGES MORDAX SP. N. (ACARI: PSOROPTIDAE) FROM AN AUSTRALIAN DASYURID MARSUPIAL

Abstract
Petauralges mordax sp. n. from Phascogale tapoatafa (Meyer) is the second species of this listropsoralgine genus to be recorded from Australia. The other genera in the subfamily are Neotropical.     

A new freshwater halacarid mite, genus Peregrinacarus (Halacaridae, Acari) from the Falklands

Peregrinacarus falklandensis n. sp., a halacarid mite from an East Falkland creek, is described and illustrated. This is the second Peregrinacarus species to date. The other species, P. reticulatus Bartsch, is recorded from Marion Island, Indian Ocean. The two species differ in chaetotaxy of the legs. The presence of halacarids in freshwater of southern polar and adjacent regions is discussed.     

Description and proposed life cycle of Maritrema novaezealandensis n. sp. (Microphallidae) parasitic in red-billed gulls, Larus novaehollandiae scopulinus, from Otago Harbor, South Island, New Zealand

Maritrema novaezealandensis n. sp. is described from Otago Harbor, South Island, New Zealand, on the basis of adult specimens collected from the Red-billed gull, Larus novaehollandiae scopulinus, and excysted metacercariae obtained from crabs. It belongs to the "eroliae group" and differs from other related species mainly in the shape, size, and patterns of distributions of the spines on the cirrus, the shape of the metraterm, the presence of an unlobed ovary, and the complete ring of the vitelline follicles. Based on morphometric features of metacercariae and adult specimens, the trophic relationships among invertebrate and vertebrate hosts, experimental infections, and previous reports of species of Maritrema with similar transmission patterns, the life cycle of M. novaezealandensis n. sp. is described. A 3-host life cycle is proposed for this parasite. The first intermediate host is the mud snail, Zeacumantus subcarinatus, in which the cercarial stage is produced in sporocysts located within the gonad of the snail. At least 3 crab species (Hemigrapsus crenulatus, Macrophtalmus hirtipes, and Halicarcinus whitei) and several species of amphipods act as second intermediate hosts, with metacercariae encysted in the body cavity of the crustacean host. Finally, the definitive host, the gull, L. n. scopulinus, harbors the adult worms in its intestine.     

Monostephanostomum georgianum n. sp. (Digenea: Acanthocolpidae) from Arripis georgianus (Valenciennes) (Perciformes: Arripidae) off Kangaroo Island,South Australia,with comments on Monostephanostomum Kruse, 1979 and Stephanostomum Looss, 1899

Monostephanostomum georgianum n. sp. is described from Arripis georgianus off Kangaroo Island, South Australia. It differs from its congeners by the presence of a short second row of oral spines. M. manteri Kruse, 1979 is reported from A. georgianus off southern Western Australia and Kangaroo Island, South Australia and A. trutta off northern Tasmania. It is considered that the other two species, M. yamagutii Ramadan, 1984 and M. krusei Reimer, 1983, should probably be removed from this genus. Two new combinations are formed, M. gazzae (Shen, 1990) n. comb. (from Stephanostomum) and M. mesospinosum (Madhavi, 1976) n. comb. (from Stephanostomum). A key to the four recognised species of Monostephanostomum is given.     

A new endogean, anophthalmous species of Parazuphium Jeannel from Northern Morocco (Coleoptera, Carabidae), with new molecular data for the tribe Zuphiini

A new species of the genus Parazuphium (Coleoptera, Carabidae, Zuphiini), Parazuphium aguileraisp. n., is described from the Tingitan peninsula in North Morocco. The only known specimen was found under a large deeply buried boulder, and belongs to an anophthalmous, depigmented and flattened species. This is the second species of blind Parazuphium known so far, the other being Parazuphium feloi Machado 1998 from a lava tube in the Canary Islands. Molecular data of the only known Parazuphium aguilerai sp. n. specimen are provided, and a reconstructed phylogeny based on these molecular data confirms its inclusion inside Zuphiini within Harpalinae. Identification keys to the Mediterranean and Macaronesian species of Parazuphium are provided.     

Ergasilus thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) from the gills of Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae) from southern Brazil

The female of Ergasilus thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) is described from the gills of the "jundiá," Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae), from fish ponds in the State of Rio Grande do Sul, Brazil. The new species has a falciform semipinnate terminal seta on the first exopod, which suggests phylogenetic affinity to 10 other congeners, all from fishes of the Amazon Basin. Based on general morphology, the new species shows great similarity to E. callophysus Thatcher and Boeger, 1984, a parasite of another pimelodid fish Callophysus macropterus. Ergasilus thatcheri n. sp., however, can be easily differentiated from E. callophysus in its possession of a more distal sensillum not located on a cuticular elevation, and a row of spinules on the inner margin of the second antennal segment (first endopodal segment).     

CONDITION DEPENDENCE OF A SEXUALLY SELECTED TRAIT IN A CRUSTACEAN SPECIES COMPLEX: IMPORTANCE OF THE ECOLOGICAL CONTEXT

The genic capture model offers a promising solution to the lek paradox. Heightened condition dependency of sexually selected traits is a prerequisite of this model. Condition dependency is empirically inferred by the sensitivity of traits to stressors. The magnitude of ecological stress (e.g., competition and predation) experienced by populations varies considerably. Thus, condition dependence should manifest more in populations experiencing higher levels of stress. We experimentally assessed the sensitivity of a sexually selected trait (posterior gnathopod) to food resource stress in an amphipod species. We found that gnathopod size variation was 59% higher under food stress, with no corresponding effect on nonsexually selected traits. In addition, we assessed levels of gnathopod variation and the allometry of gnathopods for males sampled from natural populations for two amphipod species that experience different levels of stress (driven by contrasting size‐selective predation and associated life‐history trade‐offs). Populations that experience higher resource stress had both steeper allometries and greater gnathopod size variation. These results suggest that the magnitude of ecological stress experienced by natural populations strongly impacts condition dependency of sexually selected traits, and could play an important role in shaping trait variation and thus the opportunity for sexual selection.