Meals for two: foraging activity of the butterflyfish Chaetodon striatus (Perciformes) in southeast Brazil.

The banded butterflyfish (Chaetodon striatus) from the tropical and subtropical western Atlantic is a territorial, diurnal forager on benthic invertebrates. It is usually seen moving singly or in pairs, a few meters above the sea floor. We studied the foraging activity of C. striatus on rocky reefs in southeastern Brazil. This fish spent about 11 h and 30 min per day on feeding activities, and preferred colonies of non-scleratinian anthozoans over sandy and rocky substrata while foraging. The lowest feeding rates were recorded in the early morning and late afternoon, but we found no further differences between feeding rates throughout the day. We also found no differences between the feeding rates of paired and single individuals.     

Eimeria ovata n. sp. and Other Coccidia of the Eastern Chipmunk Tamias striatus in Massachusetts

SYNOPSIS. Eimeria vilasi, E. wisconsinensis , and E. ovata n. sp. were found in the intestinal contents of eastern chipmunks Tamias striatus in Massachusetts. The oocysts of E. ovata are ovoid with mean dimensions of 26.1 × 16.7 μ. The outer oocyst wall is rough, with small pits. Micropyle and oocyst residuum are absent. Sporulation time at room temperature is 7–8 days.     

Morphology and Phylogeny of Two Species of Loxodes (Ciliophora,Karyorelictea), with Description of a New Subspecies,Loxodes striatus orientalis subsp. n.

The morphology and phylogeny of Loxodes vorax and L. striatus orientalis subsp. n. were investigated based on infraciliature and small subunit (SSU) rRNA gene sequence data. Loxodes striatus orientalis subsp. n. was separated from L. striatus striatus stat. n. by having fewer dikinetids in the intrabuccal kinety (35–55 vs. 50–70) and a variable number of macronuclei (2–4 vs. 2). In addition, the SSU rRNA gene sequence of the new subspecies differs in 13 and 11 nucleotides from that of two populations of the nominotypic subspecies. We also summarized the morphological differences between Loxodes and Remanella based on the data available. Phylogenetic analyses revealed that the genus Loxodes was monophyletic and nested within Remanella species. This study might, therefore, support the hypothesis that the freshwater genus Loxodes evolved from the marine genus Remanella.     

Reproductive phenology in three Genisteae (Fabaceae) shrub species of the W Mediterranean Region

We studied the flower duration, the phenology of flowering and fruiting, and flower, fruit, and seed production in three Genisteae shrub species of the W Mediterranean Region: Cytisus multiflorus, C. striatus , and Retama sphaerocarpa . Flower duration was negatively correlated with temperature, and in the case of C. striatus it was also influenced by pollination. In Cytisus multiflorus , which flowers during winter in the population studied, two floral morphs were recognized differentiated by flower size, phenological pattern, and production of the reproductive organs: morph LF (large flowers) and morph SF (small flowers). The former is earlier in phenology but its reproductive success is less than the second since it not only produces significantly fewer flowers/plant, but also a smaller crop of fruit and seeds. The flowering of the LF morph lasted some three months and of the SF morph 11 weeks. The winter-spring flowering C. striatus , with a four month duration of flowering time, is sympatric with C. multiflorus and their flowering periods overlap, but the former is more successful reproductively. Retama sphaerocarpa is clearly spring flowering, with an extremely short duration of flowering (c. 6.5 weeks), but, unlike the other two species which disperse their seeds in the same season in which they are produced, it staggers the dispersal of its diaspores over more than one year. Despite the great flower per plant production, especially in Retama sphaerocarpa , and of the number of fruit initiated, the final crop of fruit and seed/plant is low in the three species (C. multiflorus : fruit 8.40% and seeds 1.96%; C. striatus : fruit 13.09% and seeds 4.12%; Retama sphaerocarpa : fruit 5.65% and seeds 1.33%).     

Serological examination of a rhabdovirus isolated from snakehead (Ophicephalus striatus) in Thailand with ulcerative syndrome

A rhabdovirus has been isolated from snakehead (Ophicephalus striatus) in Thailand showing an ulcerative syndrome. The virus did not exhibit any serological relationship to VHSV, IHNV, RVC, PFRV or EVX.

Zusammenfassung

Serologische Untersuchung eines Rhahdovirusisolates vom Schlangenkopffisch (Ophicephalus striatus) mit ulcerativem Syndrom in Thailand
Von einem Schlangenkopffisch (Ophicephalus striatus) mit dem ulcerativem Syndrom wurde ein Rhabdovirus in Thailand isoliert, das keine serologische Verwandtschaft zu VHSV, IHNV, RVC, PFRV und EVX aufweist.

Résumé

Examen sérologique d'un rhabdovirus isolé de Ophicephalus striatus avec syndrome ulcératif en Thaïlande
En Thaïlande un rhabdivirus a été isolé de Ophicephalus striatus montrant un syndrome ulcératif. Le virus ne montrait aucune relation sérologique avec VHSV, IHNV, RVC, PFRV ou EVX.     

On the Parasitic Protozoa of Liberia. V. Coccidia of Liberian Rodents.

SYNOPSIS. In a survey of coccidia of rodents from Harbel, Libera, the following species of Eimeria were found and described: E. musculoidei n. sp. from Mus (Leggada) musculoides; E. separata Becker & Hall, 1931 from Rattus (Dephomys) defua (new host record); E. praomysis n. sp. from Rattus (Praomys) tullbergi rostratus; E. dasymysis n. sp. from Dasymys incomptus rufulus; E. lemniscomysis n. sp. from Lemniscomys striatus striatus; and E. lophuromysis n. sp., E. sikapusii n. sp., E. liberiensis n. sp., E. harbelensis n. sp., E. africana n. sp., and E. kruidenieri n. sp. from Lophuromys sikapusi sikapusi.     

Chromosomal evolution in the African Arvicanthine rats (Murinae, Rodentia): comparative cytogenetics of Lemniscomys (L. zebra, L. rosalia, L. striatus) and Arvicanthis dembeensis

Chromosomenevolution bei den afrikanischen arvicanthinen Ratten (Murinae, Rodentia): Vergleichende Cytogenetik von Lemniscomys (L. zebra, L. rosalia, L. striatus) und Arvicanthus dembeensis
Chromosomenbänderungsanalysen (G- und C- Bänderung) wurden an zwei Arten von Lemniscomys ( L. zebra, L. rosalia ) und einer dritten Art aus Benin ( L. striatus ) durchgeführt, um den Verlauf der Chromosomenevolution in dieser Gattung zu verfolgen. Ein Mustervergleich mit der G-Bänderung macht es möglich, die Umstrukturierung der Chromosomen der Karyotypen zu erkennen. Die beiden Arten aus Tansania ( L. rosalia 2n=54, FNa=62; und L. zebra 2n=54, FNa=58) sind durch zwei perizentrische Inversionen voneinander unterschieden. Ein Polymorphismus für das X-Chromosom findet sich in beiden Arten. L. rosalia zeigt außerdem zwei verschiedene Formen des Y-Chromosoms. Das Bänderungsmuster von L. striatus (2n=44, FNa=68) aus Benin läßt im Vergleich zu L. zebra fünf Robertsonsche Fusionen erkennen. Außerdem ist der Karyotyp von L. rosalia aus Tansania verschieden von dem der für Südafrika (2n=48, FNa=62) beschrieben wurde und sollte daher als eine eigene Art betrachtet werden. Eine vergleichende Bänderungsanalyse mit einer anderen arvicanthinen Art ( Arvicanthus dembeensis, 2n=62, FNa=62) zeigt zwischen den beiden Gattungen eine vollständige Homologie in den G-Banden und die Unterschiede beruhen ausschließlich auf Tandem-Fusionen, perizentrischen Inversionen und Robertsonschen Fusionen.     

Parasites of commercial shrimps and fishes in Argentine sea: on the adult and metacercaria of Opecoeloides feliciae n. sp. (Digenea: Opecoelidae).

Opecoeloides feliciae n. sp., first record of opecoelid metacercariae in commercial shrimps of South Atlantic Ocean, parasitizing Cynoscion striatus (adults) and Artemesia longinaris (metacercariae), is described, illustrated and compared with related species of the genus. Adults, immature worms and metacercariae are compared, and rates of prevalence and intensity of infection are also given.     

Contrasts in algal food processing among five herbivorous coral-reef fishes

There were significant differences among five sympatric herbivorous reef fish species in their ranking of seven food-processing characters. Between them Zebrasoma scopas and Stegastes nigricans had the lowest bite rates, longest filling times, lowest defaecation activities and slowest gut turnover. Acanthurus nigrofuscus and Scarus sordidus were similar in having the fastest filling times, and high bite rates, gut-contents masses, gut turnover and defaecation activities. Ctenochaetus striatus was intermediate between those species pairs in five out of seven characters. Rich algal diets of S. nigricans and Z. scopas were contrasted with the carbonate intake of S. sordidus . The food-processing pattern of C. striatus was related to the siliceous content of a diatom diet. Food-processing characteristics of A. nigrofuscus were attributed to a diet which is readily absorbed and/or is of high nutritional quality.     

Linkage strategies for genetically complex traits. II. The power of affected relative pairs.

The power to detect disease-susceptibility loci through linkage analysis using pairs of affected relatives and affected-unaffected pairs is examined. Allelic identity by descent (ibd) for a completely polymorphic marker for sibling, uncle-nephew, grandparent-grandchild, half-sib, and first-cousin pairs is considered. Affected-unaffected pairs generally represent a poor strategy. For single-locus models, ibd depends on lambda R, the risk ratio for type R relatives compared with population prevalence, and the recombination fraction theta. The ibd for grandparent-grandchild pairs is least affected by recombination, followed by sibs, half-sib, uncle-nephew, and first-cousin pairs. For diseases with large lambda values and for small theta values, distant relatives offer greater power. For larger theta values, grandparent-grandchild pairs are best; for small lambda values, sibs are best. Additive and multiplicative multilocus models are considered. For the multiplicative model, the same formulas as in the single-locus model apply, except that lambda iR (for the ith contributing locus) is substituted for lambda R. For the additive model, the deviation from null expectation for ibd is divided among all contributing loci. Compared with the multiplicative model, for an additive model there is usually greater advantage in distant relationships. Multipoint analysis using linked marker loci for affected relative pairs is described. Simultaneous use of multiple markers diminishes the effect of recombination and allows for localization of the disease-susceptibility locus.     

Studies on ciliated protozoa in eutrophic lakes: 1. Seasonal distribution in relation to thermal stratification and hypolimnetic anoxia

An investigation into the spatial and temporal distribution of ciliate populations in a small monomictic eutrophic lake was carried out over a one-year period. A community of large cilates dominated by Loxodes striatus, L. magnus, Spirostomum teres and Frontonia leucas occurred in the deep water sediments during the period of winter mixis. These cilates vacated the sediment during summer stratification, progressively colonising the hypolimnion in phase with the upwards spread of anoxic conditions, returning once more to the sediment following destratification. The possible significance of this ciliate community is discussed.     

Positive co‐occurrence between feeding‐associative savannah fishes depends on species and habitat

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Conkunitzin-S1 is the first member of a new Kunitz-type neurotoxin family. Structural and functional characterization

Conkunitzin-S1 (Conk-S1) is a 60-residue neurotoxin from the venom of the cone snail Conus striatus that interacts with voltage-gated potassium channels. Conk-S1 shares sequence homology with Kunitz-type proteins but contains only two out of the three highly conserved cysteine bridges, which are typically found in these small, basic protein modules. In this study the three-dimensional structure of Conk-S1 has been solved by multidimensional NMR spectroscopy. The solution structure of recombinant Conk-S1 shows that a Kunitz fold is present, even though one of the highly conserved disulfide cross-links is missing. Introduction of a third, homologous disulfide bond into Conk-S1 results in a functional toxin with similar affinity for Shaker potassium channels. The affinity of Conk-S1 can be enhanced by a pore mutation within the Shaker channel pore indicating an interaction of Conk-S1 with the vestibule of potassium channels.     

Karyological observations on Turbellaria Proseriata: karyometric analysis ofMonocelis fusca,M. lineata (Monocelididae) andParotoplana macrostyla (Otoplanidae)

A karyometric analysis of the chromosome set of the marine turbellariansMonocelis fusca, M. lineata andParotoplana macrostyla has been carried out. The karyotype of the twoMonocelis species investigated (2n=6) is formed by three pairs of small and similarly sized chromosomes: InM. fusca, chromosome 1 is metacentric, chromosome 2 acrocentric and chromosome 3 is subtelocentric.M. lineata also presents one pair of metacentric chromosomes (chromosome 2), while chromosomes 1 and 3 are submetacentric.P. macrostyla (2n=12) reveals two pairs of large metacentric and four pairs of small chromosomes, three of which are metacentric, whereas the last is subtelocentric.     

Labeling patterns of chloroplastidic isoprenoids in cultured cells of liverwort Ptychanthus striatus.

Incorporation studies administering 2H- and 13C-labeled mevalonate (MVA) and 13C-labeled glucose to suspension cultured cells of the liverwort, Ptychanthus striatus, were carried out in order to examine the biosynthesis of the phytyl side-chain of chlorophyll a. Administration of 13C- and 2H-labeled MVA provided evidence for the involvement of the MVA pathway in the phytyl side-chain biosynthesis and preferential labeling of the farnesyl diphosphate (FPP)-derived portion. An alternate labeling pattern in the phytyl side-chain was observed which was slightly different to the non-equivalent labeling in other liverworts, such as Heteroscyphus planus and Lophocolea heterophylla and in the hornwort, Anthoceros punctatus. The labeling pattern observed after the administration of 13C-labeled glucose revealed the simultaneous involvement of the non-MVA pathway in the phytol biosynthesis of P. striatus cells.     

Qualitative and quantitative studies on DNA and RNA synthesis in Loxodes striatus nuclei.

In this study the characteristics of the synthesis of DNA and RNA in the nuclei of Loxodes were investigated. Loxodes striatus is a primitive ciliate with 2 pairs of structurally differentiated diploid nuclei, the macro- and micronuclei. The macronuclei and differentiated morphologically into a clearly recoginzable central core and an outer zone. To determine DNA and RNA synthesis, individual organisms were analyzed by autoradiography after incubating groups of cells with a 3H-labeled precursor ([3H]thymidine for DNA and [3H]uridine for RNA). The following observations were made: (A) All portions of macro- and micronuclei appeared to contain DNA as judged by the localizations of incorporated [3H]thymidine. (B) The macro- and micronuclei did not synthesize DNA at the same time; moreover, the duration of DNA synthesis in the former was much longer than of the latter nucleus. (C) Replication of DNA in the inner core and outer zone of the macronucleus occurred at separate times with little if any overlap. (D) All of the detectable [3H]uridine incorporation was found in the macronucleus and none in the micronucleus. Within the macronucleus the central core was more heavily labeled. (E) The quantitative differences in the label of the different components synthesis can occur in adult macronuclei. The possible explantion of these results is discussed in the context of the nuclear evolution of ciliates and of recent information on nuclear differentiation.     

Adaptative features of enzymes from family sciaenidae--II. Studies on phosphoglucose isomerase (PGI) of fishes from the south coast of Uruguay

1. The electrokinetic and thermostability properties of phosphoglucose isomerase (PGI) in three species of temperate fishes (Perciformes, Acanthopterygii)--Cynoscion striatus, Macrodon ancylodon and Micropogonias furnieri--have been analyzed in order to study the adaptative 2. Unlike most diploid fishes the PGI of these species seemed to be encoded by three PGI loci. 3. The subunits encoded by these loci occurred at different levels in the different tissues and organs analyzed. 4. Genetic variants at two loci (Pgi-A and Pgi-B2) were detected in Cynoscion striatus, and at one (Pgi-A) in Micropogonias furnieri. 5. The product of these loci could be separated in three PGI regions based on their electrophoretic distribution and thermostability properties. 6. The more anodal region (including isozymes and allozymes) was more thermolabile than the less anodal one, which is predominant in a single tissue skeletal muscle. 7. Relative activities of PGI isozymes were compared by Klebe's method to determine pattern of divergence of duplicated gene expression in the three species studied.     

Self-sterility in two Cytisus species (Leguminosae, Papilionoideae) due to early-acting inbreeding depression

In most angiosperms, the endosperm develops before the embryo, but with harmony between the two structures until final seed formation. In an embryological study, we show that inbreeding depression causes disharmony in development of the two structures in two Leguminosae shrubs, Cytisus multiflorus and C. striatus. Our main objective was to test the causes of self-sterility in the two species by comparing the embryological development of the self seeds with that of cross seeds. In developing selfed seeds of C. multiflorus, the embryo reaches at most the globular stage and never forms mature seeds, while in C. striatus a few mature selfed seeds are formed. In both species, the main cause of abortion of developing selfed seeds is diminished endosperm development (low values of the ratio of endosperm to embryo), which triggers collapse of the endosperm and embryo. The results indicate that self-sterility in C. striatus is postzygotic because of strong, early inbreeding depression, while in C. multiflorus there exists a mixed pre- and postzygotic mechanism; the prezygotic mechanism causes rejection of some self-pollen tubes in the style/ovary, and the early inbreeding depression triggers abortion of fertilized ovules that escaped that action.     

Implications of raccoon latrines in the epizootiology of baylisascariasis.

Raccoons (Procyon lotor) frequently establish defecation sites, termed latrines, on large logs, stumps, rocks, and other horizontally oriented structures/surfaces. These latrines are important foci of infective eggs of Baylisascaris procyonis, a nematode parasite of raccoons which is pathogenic to numerous species of mammals and birds. To examine the role of raccoon latrines in this animal-parasite interaction, we documented animal visitations to raccoon latrines in two large forested tracts and two woodlots in Indiana (USA) during 1994 and 1995. Species richness of vertebrate visitors did not differ between sites or years, but species composition differed by site and year. Fourteen mammal and 15 bird species were documented visiting raccoon latrines. Small granivorous mammals, including white-footed mice (Peromyscus leucopus), eastern chipmunks (Tamias striatus), and tree squirrels (Sciurus carolinensis, S. niger, Tamiasciurus hudsonicus) were the most common visitors to latrine sites. White-footed mice, chipmunks, white-breasted nuthatches (Sitta carolinensis), and opossums (Didelphis virginiana) were photographed foraging on undigested seeds in raccoon feces. Active foraging at latrines also was shown experimentally; seeds embedded in raccoon feces were removed at a greater rate at latrine sites than at nonlatrines. We conclude that raccoon latrines are visited routinely by a variety of vertebrates, especially small granivorous rodents and birds which forage for seeds in raccoon feces, and that raccoon latrines are probable sites of transmission of B. procyonis to susceptible mammals and birds.