20 research outputs found
An assemblage of terrestrial isopods (Crustacea) in southern Brazil and its contribution to leaf litter processing
InfluĂȘncia do estado nutricional no risco para transtornos alimentares em estudantes de nutrição
Marsupial extension in terrestrial isopods (Crustacea, Isopoda, Oniscidea)
In Oniscidea, the marsupium is a ventral pouch where the offspring develop independently of an external water source. The marsupium is formed by five pairs of overlapping oostegites that develop in the females during their reproductive period. In this study, ovigerous females of 35 species were dissected, their oostegites were extracted, and the intra-marsupial offspring were counted. Two marsupium forms were recognized: distended, in which the oostegites protrude distally in relation to the sternites; and non-distended, in which the oostegites are parallel to the sixth and seventh sternites. Armadillidium nasatum, A. vulgare, Pudeoniscus birabeni, Circoniscus gaigei and Cubaris murina, conglobating species with a non-distended marsupium, and Neotroponiscus daguerri and N. carolii, non-conglobating species with a distended marsupium, have a concavity on the ventral floor of the 6th and 7th pereionites, here called the marsupial extension. This is the first record of a marsupial extension which extends beyond the area formed by the oostegites in Oniscidea
First report of pigmentation dystrophy in terrestrial isopods, Atlantoscia floridana (van Name) (Isopoda, Oniscidea), induced by larval acanthocephalans
The observation of pigmentation alteration in isopod crustaceans induced by acanthocephalans, known as pigmentation dystrophy, has been documented in North America in species of the aquatic genera Asellus Geoffroy, 1764, Lirceus Rafinesque-Schmaltz, 1820, and Caecidotea Packard, 1871, and in Europe, in Asellus. Recently, three depigmented specimens of Atlantoscia floridana (van Name, 1940), a terrestrial isopod, occurring from >Florida, USA to northern Argentina were found showing pigmentation dystrophy and harboring larval acanthocephalans. Photographic documentation of live and preserved, infected isopods is presented. Morphometric data and photomicrographs of the male, unencysted cystacanth specimen which allowed its placement in the genus Centrorhynchus LĂŒhe, 1911 are presented. This is the first record of the phenomenon of pigmentation dystrophy in terrestrial isopod crustaceans, the first record of A. floridana infected by an acanthocephalan and the first record of a species of Centrorhynchus in a terrestrial isopod
Growth curve of Balloniscus glaber Araujo & Zardo (Crustacea, Isopoda, Oniscidea) from Parque Estadual de ItapuĂŁ, Rio Grande do Sul, Brazil Curva de crescimento de Balloniscus glaber Araujo & Zardo (Crustacea, Isopoda, Oniscidea) no Parque Estadual de ItapuĂŁ, Rio Grande do Sul, Brasil
Based on field data, this study presents the growth curve of Balloniscus glaber Araujo & Zardo, 1995, a terrestrial isopod species found in Parque Estadual de ItapuĂŁ (PEI), Rio Grande do Sul, Brazil. Specimens were monthly sampled, from May 2004 to April 2005, at PEI. Captured individuals were sexed, their cephalothorax width was measured, and the growth curve was described according to von Bertalanffy's model. Male and female growth curves are described by the equations: Wt = 2.256[1-e-0.00394(t+91.128)] and Wt = 2.588[1-e-0.00301(t+101)], respectively. Curves show differential growth between males and females, with females reaching higher W<FONT FACE=Symbol>¥</FONT>, and a slower growth rate than males. Based on theses curves, life span was estimated.<br>Esse estudo, baseado em dados de campo, esse estudo apresenta a curva de crescimento de Balloniscus glaber Araujo & Zardo, 1995, um isĂłpodo terrestre encontrado no Parque Estadual de ItapuĂŁ (PEI), Rio Grande do Sul. Os espĂ©cimes foram coletados mensalmente, de maio de 2004 a abril de 2005, no PEI. Os indivĂduos capturados foram sexados e tiveram o cefalotĂłrax mensurado e a curva de crescimento descrita a partir do modelo de von Bertalanffy. As curvas de crescimento para machos e para fĂȘmeas sĂŁo descritas pelas equaçÔes: Lt = 2,256[1-e-0,00394(t+91,128)] e Lt = 2,588[1-e-0,00301(t+101)], respectivamente. As curvas apresentam crescimento diferencial entre machos e fĂȘmeas, com fĂȘmeas atingindo maior L' mas com uma taxa de crescimento menor do que os machos. Com base na curva foi estimada a longevidade dos animais
Effect of Sulfur Content on Microbial Composition and Biodegradation of a Brazilian Diesel and Biodiesel Blend (B10)
Environmental
legislation has driven the reduction of sulfur levels
in automotive fuels worldwide (â€10 ppm). We evaluate the behavior
of microbial biomass in terms of community composition, metabolite
production, and degradation of the Brazilian blend B10, made with
ultra-low-sulfur diesel (ULSD, 6.3 ppm), high-sulfur diesel (HSD,
327 ppm), and ultra-high-sulfur diesel (UHSD, 861 ppm) during simulated
storage. The microcosm was assembled in glass flasks containing an
aqueous phase (mineral medium) and an oil phase (fuels) at two conditions
of microbial contamination: natural (âŒ10<sup>3</sup> colony-forming
units (CFU) per liter ) and inoculated (âŒ10<sup>6</sup> bacterial
cells and fungal spores per milliliter), evaluated each 10 days for
40 days. The results showed that biomass production was more pronounced
in inoculated treatment and could be described at <i>T</i><sub>40</sub> as UHSD < ULSD < HSD B10. The higher degradation
of terminal methyl ester fraction (50 ± 1%), and aromatic compounds
(46 ± 2%) was in HSD B10, and ULSD B10 suffered the lowest degradation
(23 ± 3%; 26 ± 7%, respectively) (<i>p</i> <
0.05). <i>Pseudomonas</i> (Proteobacteria) was the predominant
bacterial genus at the interface (âŒ91%), but in the water phase,
changes in relative abundance and development of <i>Pandoraea</i> (Proteobacteria) and <i>Propionispora</i> (Firmicutes)
were observed (<i>p</i> < 0.05). Ascomycota and Basidiomycota
were the most abundant fungal phyla (âŒ78%). Putative fatty
acids myristic, palmitic, stearic, oleic, linoleic, and α-linolenic
acid were detected in the water phase with high relative abundance
at all sulfur levels compared to controls (<i>p</i> <
0.05), indicating the degradation products of the fatty acid methyl
esters present in soybean biodiesel. The data set suggests that the
reduction of sulfur content may have favored microbial growth; however,
the addition of fatty acid methyl ester (FAME), additives, and the
origin of petroleum-based fuels may be a more-relevant factor in the
B10-blend aerobic biodegradation