Actinobacillus rossii sp. nov., Actinobacillus seminis sp. nov., nom. rev., Pasteurella bettii sp. nov., Pasteurella lymphangitidis sp. nov., Pasteurella mairi sp. nov., and Pasteurella trehalosi sp. nov

Evidence from numerical taxonomic analysis and DNA-DNA hybridization supports the proposal of new species in the genera Actinobacillus and Pasteurella. The following new species are proposed: Actinobacillus rossii sp. nov., from the vaginas of postparturient sows; Actinobacillus seminis sp. nov., nom. rev., associated with epididymitis of sheep; Pasteurella bettii sp. nov., associated with human Bartholin gland abscess and finger infections; Pasteurella lymphangitidis sp. nov. (the BLG group), which causes bovine lymphangitis; Pasteurella mairi sp. nov., which causes abortion in sows; and Pasteurella trehalosi sp. nov., formerly biovar T of Pasteurella haemolytica, which causes septicemia in older lambs.     

Strong seasonality of Bonamia sp. infection and induced Crassostrea ariakensis mortality in Bogue and Masonboro Sounds, North Carolina, USA

Asian oyster Crassostrea ariakensis is being considered for introduction to Atlantic coastal waters of the USA. Successful aquaculture of this species will depend partly on mitigating impacts by Bonamia sp., a parasite that has caused high C. ariakensis mortality south of Virginia. To better understand the biology of this parasite and identify strategies for management, we evaluated its seasonal pattern of infection in C. ariakensis at two North Carolina, USA, locations in 2005. Small (<50 mm) triploid C. ariakensis were deployed to upwellers on Bogue Sound in late spring (May), summer (July), early fall (September), late fall (November), and early winter (December) 2005; and two field sites on Masonboro Sound in September 2005. Oyster growth and mortality were evaluated biweekly at Bogue Sound, and weekly at Masonboro, with Bonamia sp. prevalence evaluated using parasite-specific PCR. We used histology to confirm infections in PCR-positive oysters. Bonamia sp. appeared in the late spring Bogue Sound deployment when temperatures approached 25 degrees C, six weeks post-deployment. Summer- and early fall-deployed oysters displayed Bonamia sp. infections after 3-4 weeks. Bonamia sp. prevalences were 75% in Bogue Sound, and 60% in Masonboro. While oyster mortality reached 100% in late spring and summer deployments, early fall deployments showed reduced (17-82%) mortality. Late fall and early winter deployments, made at temperatures <20 degrees C, developed no Bonamia sp. infections at all. Seasonal Bonamia sp. cycling, therefore, is influenced greatly by temperature. Avoiding peak seasonal Bonamia sp. activity will be essential for culturing C. ariakensis in Bonamia sp.-enzootic waters.     

Speciation of Protopolystoma Bychowsky, 1957 (Monogenea: Polystomatidae) in hosts of the genus shape Xenopus (Anura: Pipidae)

The taxonomy, geographical distribution and hostrange of the polystomatid genus ProtopolystomaBychowsky, 1957 are reviewed. P. xenopodis(Price, 1943) and five new species are recognised,which occur in clawed toads ( Xenopus spp.)throughout subsaharan Africa. Of the two clawed toadsubgenera, Xenopus and Silurana, only theformer is infected. Protopolystoma spp. aredifferentiated by morphological variation of the gut,large hamulus and penis armature. P.xenopodis is found in Xenopus laevis subspeciesin South Africa, Transkei, Zimbabwe, DemocraticRepublic of Congo (D.R.C.), Rwanda, Uganda, Kenya andCameroon ( X. l. poweri and X. l.sudanensis are new host records). It also occurs inintroduced populations of X. l. laevis in theUnited States (southern California) and United Kingdom(South Wales). In subsaharan Africa the speciesdisplays significant, but continuous, geographicalvariation of penis spine size between southernpopulations in X. l. laevis and those in morenortherly host subspecies. Data on the natural hostrange of this parasite were complemented by anexperimental study of host-specificity in the southernform. This can produce patent infections in X.l. victorianus and X. gilli, but not X.wittei nor X. (Silurana) tropicalis. P.simplicis n. sp. is endemic to central and eastAfrican areas, infecting X. laevis subspecies ineastern D.R.C., Rwanda, Uganda and western Kenya, X. wittei-like hosts in eastern D.R.C., westernUganda, Rwanda and Burundi, X. vestitus inwestern Uganda and Xenopus sp. at Nairobi,Kenya. P. ramulosus n. sp. occurs in X.fraseri-like toads in eastern D.R.C. (Gabon andCameroon are also possible literature records), and P. fissilis n. sp. is found in X. fraseri-and X. wittei-like species in Cameroon andeastern D.R.C., and in southern Rwanda, respectively. Two Protopolystoma taxa are found in X.muelleri populations now suspected to representdistinct species: P. occidentalis n. sp. occursin X. muelleri (western form) in Ghana, Togo,Nigeria and Cameroon, while P. orientalis n. sp.is found in X. muelleri (eastern form) in SouthAfrica, Zimbabwe and Tanzania. The allopatricallydistributed species P. ramulosus, P.simplicis, P. occidentalis and P.orientalis form a relatively homogenous grouping withsome interspecific morphological overlap. These taxaare distinguished from P. xenopodis by penisspine morphology and from P. fissilis by hamulusroot form and aspects of gut morphology. Unidentified Protopolystoma sp. have been recorded in X. clivii in Ethiopia, X. fraseri aff. inCameroon and Xenopus sp. in Kenya and Tanzania. At some localities, single host species were infectedby two representatives of Protopolystoma. P. fissilis was recorded in eastern D.R.C. with P. ramulosus, with Protopolystoma sp. inCameroon in X. fraseri-like hosts and with P. simplicis in X. wittei-like hosts in Rwanda. P. xenopodis co-occurred with P. simplicisin X. laevis subspecies through central and eastAfrica.     

A preliminary study of parasites and diseases of perch in an intensive culture system

The recent development of intensive rearing of European perch Perca fluviatilis in warm water effluents revealed important pathological problems. This study gives a preliminary overview of parasites and diseases encountered in experimental perch farming. No virus has been recorded since the beginning of the experiments in 1993. By contrast, mass mortality caused by bacterial disease alone or associated with other pathogens were frequently observed. The main identified bacterial species were: Aeromonas sp., A. veronii, A. hydrophila, Streptococcus sp., Staphylococcus sp., Vibrio fluviatilis and Enterobacter agglomerans. Protozoans were the most common parasites observed on cultured P. fluviatilis. High mortality rate due to Ichthyobodo necator and Trichodina sp. may take place at different stages of perch rearing. In contrast, the infestation by Ambiphrya sp. and Heteropolaria sp. was size- or age-related; these two ciliates infested perch weighing < 1 g and > 20 g, respectively. In spite of the presence of other parasites such as Ichthyophthirius multifiliis, Hexamita spp., Gyrodactylus sp. and Argulus sp. in the rearing system P. fluviatilis does not appear to be affected. Further abnormalities or diseases inherent to intensive culture systems are also described.     

Four New Species of Eimeria and One of Tyzzeria from the Ceylon Jungle Fowl Gallus lafayettei*

One species of Tyzzeria and 4 new species of Eimeria are described from the Ceylon jungle fowl Gallus lafayettei. The sporulated oocysts of Tyzzeria galli sp. n. are 13.8 (12–15) μ m; of Eimeria lafayettei sp. n., 19.5 (19–21) X 14.2 (13.5–15) μ m; of Eimeria indentata sp. n., 30.3 (29.5–32) X 21.4 (20–22) μ m; of Eimeria symmetrica sp. n., 35 × 28.5 μ m, and of Eimeria dissanaikei sp. n., 21 (19–23) X 14 (12–16) μ m. E. indentata, E. symmetrica, and E. dissanaikei produced patent infections in domestic fowl but T. galli and E. lafayettei did not. This is the 1st record of the genus Tyzzeria from the order Galliformes.     

Studies on endoparasites of the black bear (Ursus americanus) in the southeastern United States.

Examination of 53 black bears (Ursus americanus) from six states in the southeastern United States revealed at least 17 species of endoparasites, including Sarcocystis sp., Spirometra mansonoides (spargana), Macracanthorhynchus ingens, Ancylostoma caninum, Arthrocephalus lotoris, Baylisascaris transfuga, Capillaria aerophila, Capillaria putorii, Crenosoma sp., Cyathospirura sp., Dirofilaria immitis, Gnathostoma sp., Gongylonema pulchrum, microfilariae, Molineus barbatus, Physaloptera sp. and Strongyloides sp. Twelve of these represent new host records for black bear, and two are considered to be new species. Data are presented on prevalence, intensity and geographic distribution of each species. Pathologic effects were associated with infections of spargana of S. mansonoides and adults of C. aerophilia.     

Important disease conditions of newly cultured species in intensive freshwater farms in Greece: first incidence of nodavirus infection in Acipenser sp

We describe here the main pathological conditions of freshwater fish recently introduced for intensive rearing (open ponds and recirculating freshwater systems) in Greece. Sturgeon were susceptible to skeletal abnormalities of the spine (scoliosis and lordosis) of unknown aetiology. Horizontal transmission of nodavirus from infected sea bass to sturgeon was detected for the first time. This caused serious pathology and clinical signs, such as lethargy and imbalance, leading to secondary infections with Aeromonas hydrophila and Trichodina sp. and chronic, but steady, mortality. Sea bass were very susceptible to nodavirus infection, monogenean infections and gas bubble disease. Mullet reared under recirculated and open-flow conditions were very sensitive to Chilodonella sp. infection, whereas catfish were susceptible to infection with Ichthyophthirius sp. leading to secondary infections with A. hydrophila, Saprolegnia sp. and Myxobacteria spp. Tilapia were very susceptible to gas bubble disease and A. hydrophila. This bacterium was associated with management manipulations for all species and fully responsive to corrective hygiene methods.     

STUDY ON SUBGENUS XORIDES (HYMENOPTERA: ICHNEU-MONIDAE) FROM NORTH CHINA

Abstract  This papa deals with nine species of Xorides (Xorides ) collected in North China, of which three are new to the science, namely Xorides (X.) furcatus sp. nov., X . (X.) hirtus sp. nov. and X. (X.) aculeatus sp.nov., three, are new records, X. (X.) brachylabis , X. (X.) praecato-rius , X. (X.1 sepulchralis , and the other three species already known in China, X. (X.) sapporen-sis, X . (X.1 erigentis, X . (X.) hingganensis .     

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. IV. Four new species in Talpa europaea from England

Moles from England were examined for coccidian oocysts and all 64 Talpa europaea were infected; of 64 infected hosts, 56 (88%) had multiple infections representing two to six coccidian species when examined. Oocysts in 31 of the 64 samples remainedunsporulated. Three eimerians and one isosporan were studied from the 33 fecal samples that had sporulated oocysts and these are described as new species; Cyclospora talpae Pellérdy & Tanyi, 1968, and Isospora sofiae (Golemansky, 1978) Levine & Ivens, 1979, are redescribed; and Cyclospora sp., similar to C. talpae, is discussed. Sporulated oocysts of C. talpae are ellipsoidal, 14.3 X 9.6 (12-19 X 6-13) microns with sporocysts ovoid, 9.4 X 5.7 (6-13 X 4-8) microns; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Cyclospora sp. are subspheroidal to ellipsoidal, 12.5 X 8.9 (10-14 X 6-12) microns with sporocysts ovoid, 8.6 X 5.3 (6-10 X 4-6) microns; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Eimeria avonensis n. sp. are elongate-ellipsoidal, 15.0 X 9.6 (13-20 X 7-12) microns with sporocysts ovoid, 6.6 X 3.6 (5-9 X 3-7) microns; it was found in 15 of the 33 (45.5%) sporulated samples. Sporulated oocysts of Eimeria berea n. sp. are subspheroidal, 12.1 X 10.5 (10-15 X 8-14) microns with sporocysts ovoid, 6.3 X 3.9 (5-10 X 2-5) microns; it was found in 8 of the 33 (24.2%) sporulated samples.(ABSTRACT TRUNCATED AT 250 WORDS)     

Splenomegaly and Reticulocytosis Caused by Babesia microti Infections in Natural Populations of the Montane Vole, Microtus montanus

ABSTRACT. A survey for Babesia microti in rodents was conducted at six sites within Grand Teton National Park, Wyoming. Blood and spleen smears, hematocrits, and reticulocyte counts were made on all of the animals to evaluate parameters for the diagnosis of babesiosis. Ticks were removed for identification. Of 257 Microtus montanus , 103 were infected with B. microti. In addition, five of 12 Microtus pennsylvanicus and one of three Arvicola richardsoni were parasitized by B. microti. Peromyscus maniculatus (n = 40) were not infected. Concurrent infections by Hepatozoon sp., Trypanosoma sp., and the bacterium, Grahamella sp., were noted in blood smears from a number of M. montanus. Splenomegaly and reticulocytosis were significant parameters associated with babesiosis while decreased hematocrit was not. Ticks removed from the voles were identified as Ixodes eastoni and were the probable vectors of the B. microti.     

Splenomegaly and reticulocytosis caused by Babesia microti infections in natural populations of the montane vole, Microtus montanus.

A survey for Babesia microti in rodents was conducted at six sites within Grand Teton National Park, Wyoming. Blood and spleen smears, hematocrits, and reticulocyte counts were made on all of the animals to evaluate parameters for the diagnosis of babesiosis. Ticks were removed for identification. Of 257 Microtus montanus, 103 were infected with B. microti. In addition, five of 12 Microtus pennsylvanicus and one of three Arvicola richardsoni were parasitized by B. microti. Peromyscus maniculatus (n = 40) were not infected. Concurrent infections by Hepatozoon sp., Trypanosoma sp., and the bacterium, Grahamella sp., were noted in blood smears from a number of M. montanus. Splenomegaly and reticulocytosis were significant parameters associated with babesiosis while decreased hematocrit was not. Ticks removed from the voles were identified as Ixodes eastoni and were the probable vectors of the B. microti.     

A retrospective study of the microbiological and parasitological status of laboratory rodents in France

Between 1988 and 1997, 72 mouse colonies and 38 rat colonies were examined for the presence of bacteria parasite infections. Among mouse and rat bacteria, high positive rates were observed with Proteus species (sp.), Pasteurella pneumotropica, Mycoplasma sp. and Pseudomonas aeruginosa. Concerning murine colonies, parasites frequently detected were Tritrichomonas sp., Syphacia sp., Aspiculuris tetraptera, Entamoeba muris, Spironucleus muris, Myobia musculi, Chilomastix sp. and Myocoptes musculinus. In rats, high rates were obtained with Syphacia sp., Tritrichomonas sp., Spironucleus muris, Entamoeba muris and Chilomastix sp. During the first part of the last decade, some agents such as Clostridium piliforme, Citrobacter sp., Mycoplasma sp., Pseudomonas aeruginosa, Myobia musculi, Radfordia ensifera, Spironucleus muris and Giardia muris were often found among rodents, and most of them were still present in 1997. At the time of our study, results point out that some agents are still persistent, even increasing during the same period. It is particularly the case for parasites such as Entamoeba muris and the oxyurids, but also for bacteria like Proteus sp. and Klebsiella pneumoniae. We can thus conclude that only very limited success has been achieved in preventing microbial and parasitic infections in mice and rats colonies.     

Some aspects of protozoan infections in immunocompromised patients- a review

Protozoa are among the most important pathogens that can cause infections in immunocompromised hosts. These microorganisms particularly infect individuals with impaired cellular immunity, such as those with hematological neoplasias, renal or heart transplant patients, patients using high doses of corticosteroids, and patients with acquired immunodeficiency syndrome. The protozoa that most frequently cause disease in immunocompromised patients are Toxoplasma gondii, Trypanosoma cruzi, different Leishmania species, and Cryptosporidium parvum; the first two species cause severe acute meningoencephalitis and acute myocarditis, Leishmania sp. causes mucocutaneous or visceral disease, and Cryptosporidium can lead to chronic diarrhea with hepatobiliary involvement. Various serological, parasitological, histological and molecular methods for the diagnosis of these infections are currently available and early institution of specific therapy for each of these organisms is a basic measure to reduce the morbidity and mortality associated with these infections.     

Pathogens of bark beetles (Curculionidae: Scolytinae) and other beetles in Bulgaria

The presence and diversity of beetle pathogens associated with different tree species in Bulgaria was investigated. In total, 818 specimens belonging to 22 beetle species were examined. Pathogens occurred in 9 host species. The infections were found in the gut (virus, nematodes, protozoans, microsporidia) and haemolymph (nematodes) of the infected insects. The following pathogen species: ItEPV, Beauveria bassiana, B. brongniartii, Isaria farinosa, Gregarina typographi, Gregarina spp., Chytridiopsis typographi, Chytridiopsis sp., and nematodes were revealed. Insects with mycoses were mummified and filled up with fungal structures, formed pseudosclerotium. Most pathogens were established in bark beetles (Scolytinae). For the first time, the fungus B. bassiana was reported in Tomicus piniperda, Orthotomicus longicollis, O. erosus, X. spinole, Taphrorychus villifrons and Phylobius sp. in Bulgaria. We also present the first records of gregarines in O. longicollis, Acanthocinus aedilis, Rhagium inquisitor, Pyrochroa coccinea, and of the microsporidium Chytridiopsis sp. in O. longicollis.     

Coccidian parasites (Apicomplexa: Eimeriidae) of Microtus spp. (Rodentia: Arvicolidae) from the United States, Mexico, and Japan, with descriptions of five new species

Beginning in July 1980, 149 voles (Microtus spp.) representing 9 species and 14 subspecies collected in Japan, Mexico and the United States were examined for coccidia; 67 (45%) had oocysts in their feces. These included 1 of 3 (33%) M. californicus sactidiegi; 0 of 1 M. longicaudus longicaudus; 0 of 1 M. l. macrurus; 48 of 111 (43%) M. mexicanus including 11 of 26 (42%) M. m. fulviventer, 1 of 2 (50%) M. m. fundatus, 13 of 31 (42%) M. m. mexicanus, 1 of 4 (25%) M. m. mogollonensis and 22 of 48 (46%) M. m. subsimus; 5 of 8 (63%) M. montanus arizonensis; 6 of 6 M. montebelli montebelli; 2 of 4 (50%) M. oregoni oregoni; 5 of 13 (38%) M. pennsylvanicus pennsylvanicus; 0 of 1 M. quasiater and 0 of 1 M. townsendii townsendii. The following coccidians were identified from infected voles: Eimeria saxei n. sp. (syn. E. wenrichi "B") from M. c. sactidiegi; E. ochrogasteri, E. saxei, E. wenrichi (syn. E. wenrichi "A"), and Eimeria sp. from M. m. fulviventer, Eimeria sp. from M. m. fundatus; E. ochrogasteri, E. saxei, Eimeria tolucadensis n. sp., E. wenrichi, and Eimeria sp. from M. m. mexicanus; E. wenrichi from M. m. mogollonensis; Eimeria coahuiliensis n. sp., E. saxei, Eimeria subsimi n. sp., E. wenrichi, Eimeria sp., and Isospora mexicanasubsimi n. sp. from M. m. subsimus; E. tamiasciuri and E. wenrichi from M. m. arizonensis; Eimeria spp. from M. m. montebelli; E. saxei and E. wenrichi from M. o. oregoni; and E. ochrogasteri and E. wenrichi from M. p. pennsylvanicus. Sporulated oocytsts of Eimeria coahuiliensis n. sp. were ellipsoid, 29.6 X 19.6 (27-34 X 18-22) micron with ovoid sporocysts 14.4 X 8.9 (13-18 X 8-10) microns. Sporulated oocysts of Eimeria saxei n. sp. were subspheroid, 13.0 X 11.0 (11-14 X 10-12) micron with ovoid sporocysts 7.5 X 4.0 (6-9 X 4-5) micron. Sporulated oocysts of Eimeria subsimi n. sp. were ovoid/subspheroid, 25.1 X 18.7 (22-28 X 17-21) micron with ellipsoid sporocysts 13.9 X 7.4 (13-15 X 6-8) micron. Sporulated oocysts of Eimeria tolucadensis n. sp. were subspheroid, 25.4 X 20.3 (23-26 X 19-23) micron with ellipsoid sporocysts 11.3 X 7.8 (10-13 X 7-9) micron. Sporulated oocysts of Isospora mexicanasubsimi n. sp. were subspheroid, 23.7 X 23.1 (21-26 X 21-26) micron with ovoid sporocysts 14.9 X 10.8 (12-16 X 10-12) micron.(ABSTRACT TRUNCATED AT 400 WORDS)     

Description of four novel species of Xenorhabdus, family Enterobacteriaceae: Xenorhabdus budapestensis sp. nov., Xenorhabdus ehlersii sp. nov., Xenorhabdus innexi sp. nov., and Xenorhabdus szentirmaii sp. nov

The taxonomic affiliation was determined for four Xenorhabdus strains isolated from four Steinernema hosts from different countries. As compared to the five validly described Xenorhabdus species, i.e., X. nematophila, X. japonica, X. beddingii, X. bovienii and X. poinarii, these isolates represented novel species on the basis of 16S rRNA gene sequences and riboprint patterns, as well as by physiological and metabolic properties. They were named Xenorhabdus budapestensis sp. nov., type strain DSM 16342^T, isolated from Steinernema bicornutum; Xenorhabdus ehlersii sp. nov., type strain DSM 16337^T, isolated from Steinernema serratum; Xenorhabdus innexi sp. nov., type strain DSM 16336^T isolated from Steinernema scapterisci; and Xenorhabdus szentirmaii sp. nov., type strain DSM 16338^T, isolated from Steinernema rarum.     

中国东北辽宁省西部几种中生代化石木

对产自辽宁省西部中生代化石木进行了解剖学研究。经鉴定,它们是：朝阳原始云杉型木（新种）（Ｐｒｏｔｏｐｉｃｅｏｘｙｌｏｎ ｃｈａｏｙａｎｇｅｎｓｅ Ｄｕａｎ ｓｐ．ｎｏｖ．）,西部南洋杉型木（Ａｒａｕｃａｒｉｏｘｙｌｏｎ ｓｉｄｕｇａｗａｅｎｓｅ Ｓｈｉｍａｋｕｒａ）,巴图南洋杉型木（新种）（Ａｒａｕｃａｒｉｏｘｙｌｏｎ ｂａｔｕｅｎｓｅ Ｄｕａｎ ｓｐ．ｎｏｖ．）和辽西紫杉型木（新种）（Ｔａｘｏｘ     

Enumeration and isolation of cellulolytic and hemicellulolytic bacteria from human feces

The fibrolytic microbiota of the human large intestine was examined to determine the numbers and types of cellulolytic and hemicellulolytic bacteria present. Fecal samples from each of five individuals contained bacteria capable of degrading the hydrated cellulose in spinach and in wheat straw pretreated with alkaline hydrogen peroxide (AHP-WS), whereas degradation of the relatively crystalline cellulose in Whatman no. 1 filter paper (PMC) was detected for only one of the five samples. The mean concentration of cellulolytic bacteria, estimated with AHP-WS as a substrate, was 1.2 X 10(8)/ml of feces. Pure cultures of bacteria isolated on AHP-WS were able to degrade PMC, indicating that interactions with other microbes were primarily responsible for previous low success rates in detecting fecal cellulolytic bacteria with PMC as a substrate. The cellulolytic bacteria included Ruminococcus spp., Clostridium sp., and two unidentified strains. The mean concentration of hemicellulolytic bacteria, estimated with larchwood xylan as a substrate, was 1.8 X 10(10)/ml of feces. The hemicellulose-degrading bacteria included Butyrivibrio sp., Clostridium sp., Bacteroides sp., and two unidentified strains, as well as four of the five cellulolytic strains. This work demonstrates that many humans harbor intestinal cellulolytic bacteria and that a hydrated cellulose source such as AHP-WS is necessary for their consistent detection and isolation.     

Enumeration and isolation of cellulolytic and hemicellulolytic bacteria from human feces.

The fibrolytic microbiota of the human large intestine was examined to determine the numbers and types of cellulolytic and hemicellulolytic bacteria present. Fecal samples from each of five individuals contained bacteria capable of degrading the hydrated cellulose in spinach and in wheat straw pretreated with alkaline hydrogen peroxide (AHP-WS), whereas degradation of the relatively crystalline cellulose in Whatman no. 1 filter paper (PMC) was detected for only one of the five samples. The mean concentration of cellulolytic bacteria, estimated with AHP-WS as a substrate, was 1.2 X 10(8)/ml of feces. Pure cultures of bacteria isolated on AHP-WS were able to degrade PMC, indicating that interactions with other microbes were primarily responsible for previous low success rates in detecting fecal cellulolytic bacteria with PMC as a substrate. The cellulolytic bacteria included Ruminococcus spp., Clostridium sp., and two unidentified strains. The mean concentration of hemicellulolytic bacteria, estimated with larchwood xylan as a substrate, was 1.8 X 10(10)/ml of feces. The hemicellulose-degrading bacteria included Butyrivibrio sp., Clostridium sp., Bacteroides sp., and two unidentified strains, as well as four of the five cellulolytic strains. This work demonstrates that many humans harbor intestinal cellulolytic bacteria and that a hydrated cellulose source such as AHP-WS is necessary for their consistent detection and isolation.     

Experimental deep-sea deployments reveal diverse Northeast Pacific wood-boring bivalves of Xylophagainae (Myoida: Pholadidae)

Only a single species of deep-sea wood boring bivalve has beenknown off the forested northwest coast of North America, althoughthe Xylophagainae are so diverse in other areas that up to fivespecies occur in a given length of wood. To determine whetheradditional species were present in the Northeast Pacific andif so, how they coexist, lengths of wood were experimentallydeployed on heavily sedimented sites on the Cascadia Basin andEscanaba Trough, non-hydrothermally active basalt on Gorda Ridgeand Axial Volcano, and an isolated sediment pond within theaxis of Juan de Fuca Ridge, at depths of between 1,530 and 3,232 m.All locations were between 41°and 48°N, at least 240 kmoff the North American coast. Six previously unknown species,Xylophaga corona n. sp., X. zierenbergi n. sp., X. heterosiphonn. sp., X. oregona n. sp., X. microchira n. sp. and Xylopholascrooki n. sp., were collected and are described here. Dominantspecies differed in recoveries made after 10 and 24 months atJuan de Fuca Ridge and Cascadia Basin localities. Xylophagamicrochira n. sp. dominated four of five deployments recoveredwithin 12 months, but its abundance declined by 24 months, beinglargely replaced on Juan de Fuca Ridge by X. oregona n. sp.,a species known only from this Ridge and from an incidentalcollection on the Nootka Fracture Zone. At Cascadia Basin sites,the abundances of X. heterosiphon n. sp. and of what are likelyto be predatory polyclad flatworms increased as that of X. microchiran. sp. declined. Xylophaga microchira n. sp. is hypothesizedto be specialized for early colonization, but to be competitivelyinferior to X. oregona n. sp., and more vulnerable to predatorsthan X. heterosiphon n. sp. The dominance of competitively superiorand more predator-resistant species in older deployments arguesthat biotic interactions contribute to coexistence of multiplespecies of wood-borers despite direct competition among them. (Received 2 February 2007; accepted 16 August 2007)