INTERSEXUALITY IN THE FRESHWATER CRAYFISH SAMASTACUS SPINIFRONS (PHILIPPI, 1882) (DECAPODA, PARASTACIDAE)

Crustaceana ◽  
1999 ◽  
Vol 72 (3) ◽  
pp. 325-337 ◽  
Author(s):  
Erich Rudolph
Keyword(s):  
Freshwater Crayfish ◽  
South American ◽  
Southern Chile ◽  
Morphometric Analyses ◽  
Males And Females ◽  
Normal Males

AbstractSamastacus spinifrons, a South American freshwater crayfish, has always been characterized as gonochoric in the literature. Yet, in 1989, a specimen with anomalous sexual characters was captured in the river Hueyusca. Since then, 13 other specimens showing such anomalous features have been collected in various rivers in the Osorno province, southern Chile. Anatomical dissections disclosed that 4 of them had testes; 4 others had ootestes and 5 had ovaries. Further, all the specimens had gonoducts and gonopores of both sexes, except in one of those with ovaries, wich had oviducts only. Morphometric analyses of abdomens of normal males and females, in comparison with those of intersexual specimens showed that the latter have abdomens with male characteristics. These conditions are all described, the frequency of the phenomenon is reported and a possible explanation for its occurrence is proposed. El camaron de rio de Sudamerica, Samastacus spinifrons, siempre ha sido caracterizado como gonocorico por la literatura. Sin embargo, en 1989 se capturo en el rio Hueyusca un especimen con caracteres sexuales anomalos. Desde entonces, se han colectados otros 13 especimenes con caracteres anomalos en varios rios de la provincia de Osorno, en el sur de Chile. Las disecciones anatomicas demostraron que 4 de ellos tenian testiculos, otros 4 tenian ovotestis, y 5 tenian ovarios. Ademas, todos tenian gonoductos y gonoporos de ambos sexos, excepto uno de aquellos con ovarios que solo tenia oviductos. Analisis morfometricos de los abdomenes de los machos y hembras normales, comparados con aquellos de especimenes intersexo demostraron que estos ultimos tienen un abdomen con caracteristicas masculinas. Se describen todas estas condiciones, se comunica la frecuencia de ocurrencia de este fenomeno y se propone una probable explicacion para el.

scholarly journals Evolving in islands of mud: old and structured hidden diversity in an endemic freshwater crayfish from the Chilean hotspot

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pedro F. Victoriano ◽  
Guillermo D’Elía
Keyword(s):  
Southeastern Brazil ◽  
Freshwater Crayfish ◽  
South American ◽  
Southern Chile ◽  
Effective Population ◽  
Conservation Units ◽  
Genetic Groups ◽  
The Pacific ◽  
Conservation Actions ◽  
Andean Uplift

AbstractParastacus is a genus of South American freshwater crayfishes disjunctively distributed in southern Chile, Northern Argentina, Uruguay and Southeastern Brazil. Parastacus pugnax is a Chilean endemic distributed along 700 km of latitude in central-southern Chile from the Pacific coast to the Andean piedmont, which is intensively captured for consumption for local communities. Considering the habitat (wet meadows) and natural history (primary burrower, non-migrant) of the species, we tested a hypothesis of highly structured genetic diversity using mtDNA of 465 specimens gathered at 56 localities across the species range. The crown age of P. pugnax was estimated at 38 Ma, predating the main Andean uplift. The genetic variation of P. pugnax is large and geographically structured. In some cases, genetic groups do not match basin limits, suggesting a previous to current dynamic of basin evolution. The uncovered intraspecific main lineages have different demographic histories. A latitudinal cline in past effective population size reduction suggests environmental singularities with a glacial effect in the southern populations. We suggest adding morphologic and more genetic data in order to assess species limits. Our results contribute to improve future conservation actions for this taxon, providing basic information to delimit conservation units.

GONADOTROPHIN PATTERNS IN MALE AND FEMALE RATS:

1968 ◽  
Vol 58 (4) ◽  
pp. 600-612 ◽  
Author(s):  
Robert Boyd ◽  
Donald C. Johnson
Keyword(s):  
Ascorbic Acid ◽  
Testosterone Propionate ◽  
Female Rats ◽  
Female Rat ◽  
Feedback Effects ◽  
Male And Female ◽  
Prostate Weight ◽  
Male And Female Rats ◽  
Males And Females ◽  
Normal Males

ABSTRACT The effects of various doses of testosterone propionate (TP) upon the release of luteinizing hormone (LH or ICSH) from the hypophysis of a gonadectomized male or female rat were compared. Prostate weight in hypophysectomized male parabiotic partners was used to evaluate the quantity of circulating LH. Hypophyseal LH was measured by the ovarian ascorbic acid depletion method. Males castrated when 45 days old secreted significantly more LH and had three times the amount of pituitary LH as ovariectomized females. Administration of 25 μg TP daily reduced the amount of LH in the plasma, and increased the amount in the pituitary gland, in both sexes. Treatment with 50 μg caused a further reduction in plasma LH in males, but not in females, while pituitary levels in both were equal to that of their respective controls. LH fell to the same low level in partners of males or females receiving 100 μg TP. When gonadectomized at 39 days, males and females had the same amount of plasma LH, but males had more stored hormone. Pituitary levels were unchanged from controls following treatment with 12.5, 25 or 50 μg TP daily, but plasma values dropped an equal amount in both sexes with the latter two doses. Androgenized males or females, gonadectomized when 39 days old, were very sensitive to the effects of TP and plasma LH was significantly reduced with 12.5 μg daily. Pituitary LH in androgenized males was higher than that of normal males but was reduced to normal by small amounts of TP. The amount of stored LH in androgenized females was not different from that of normal females and it was unchanged by any dose of TP tested. Results are consistent with the conclusion that the male hypothalamic-hypophyseal axis is at least as sensitive as the female axis to the negative feedback effects of TP. Androgenization increases the sensitivity to TP in both males and females.

Lethal mutations in Euphydryas aurinea beckeri (Lederer, 1853) (Lepidoptera: Nymphalidae) from Sierra Blanca, Malaga, Spain

2019 ◽  
Vol 70 (4) ◽  
pp. 211-216
Author(s):  
Jim Pateman ◽  
Peter Russell
Keyword(s):  
The Other ◽  
Lethal Mutations ◽  
Males And Females ◽  
Normal Males

Two Euphydryas aurinea beckeri females from Sierra Blanca, Malaga, Spain were captured and returned to the U.K.; each laid a single egg batch on Succisa pratensis. Both batches hatched and the resulting larvae were reared through to adulthood. One group of larvae produced butterflies with three different mutations: pupae with spines, legs lacking distal tarsals and claws, and with appendages attached to the genitalia which protruded though the rear of the abdomens in both males and females. The other group of larvae produced normal males and females.

A new genus and species of groundwater isopod of the family Protojaniridae (Isopoda: Asellota: Gnathostenetroidoidea) from southern Chile

Zootaxa ◽  
2021 ◽  
Vol 4966 (5) ◽  
pp. 550-562
Author(s):  
JORGE PÉREZ-SCHULTHEISS ◽  
GEORGE D. F. WILSON
Keyword(s):  
New Genus ◽  
South American ◽  
New Taxon ◽  
Southern Chile ◽  
New Genus And Species ◽  
The Third ◽  
The Family ◽  
Apical Lobe ◽  
Antennal Scale ◽  
Freshwater Springs

A new asellotan isopod of the family Protojaniridae Fresi, Idato & Scipione, 1980 is described from freshwater springs in the Osorno province, Los Lagos region, southern Chile. Wiyufiloides osornoensis gen. & sp. n. is the third South American protojanirid species and the first known groundwater isopod in Chile. The new genus and species is principally characterized by the presence of a vestigial antennal scale, a strongly subchelate pereiopod I and the absence of an apical lobe on the protopod of pleopod II. The new taxon is described in detail and figures are given. 

Morphometrical and molecular evidence suggests cryptic diversity among hookworms (Nematoda: Uncinaria) that parasitize pinnipeds from the south-eastern Pacific coasts

2018 ◽  
Vol 94 ◽  
Author(s):  
M.T. González ◽  
Z. López ◽  
J.J. Nuñez ◽  
K.I. Calderón-Mayo ◽  
C. Ramírez ◽  
...  
Keyword(s):  
Large Subunit ◽  
Principal Component ◽  
Eastern Pacific ◽  
Lsu Rdna ◽  
Molecular Evidence ◽  
South American ◽  
Southern Chile ◽  
The South ◽  
South Eastern ◽  
Neophoca Cinerea

AbstractHookworms of the genus Uncinaria parasitize pinniped pups in various locations worldwide. Four species have been described, two of which parasitize pinniped pups in the southern hemisphere: Uncinaria hamiltoni parasitizes Otaria flavescens and Arctocephalus australis from the South American coast, and Uncinaria sanguinis parasitizes Neophoca cinerea from the Australian coast. However, their geographical ranges and host specificity are unknown. Uncinaria spp. are morphologically similar, but molecular analyses have allowed the recognition of new species in the genus Uncinaria. We used nuclear genetic markers (internal transcribed spacer (ITS) and large subunit (LSU) rDNA) and a mitochondrial genetic marker (cytochrome c oxidase subunit I (COI)) to evaluate the phylogenetic relationships of Uncinaria spp. parasitizing A. australis and O. flavescens from South American coasts (Atlantic and Pacific coasts). We compared our sequences with published Uncinaria sequences. A Generalized Mixed Yule Coalescent (GMYC) analysis was also used to delimit species, and principal component analysis was used to compare morphometry among Uncinaria specimens. Parasites were sampled from A. australis from Peru (12°S), southern Chile (42°S), and the Uruguayan coast, and from O. flavescens from northern Chile (24°S) and the Uruguayan coast. Morphometric differences were observed between Uncinaria specimens from both South American coasts and between Uncinaria specimens from A. australis in Peru and southern Chile. Phylogenetic and GMYC analyses suggest that south-eastern Pacific otariid species harbour U. hamiltoni and an undescribed putative species of Uncinaria. However, more samples from A. australis and O. flavescens are necessary to understand the phylogenetic patterns of Uncinaria spp. across the South Pacific.

scholarly journals The predation of farmed salmon by South American sea lions (Otaria flavescens) in southern Chile

2009 ◽  
Vol 67 (3) ◽  
pp. 475-482 ◽  
Author(s):  
Juan Vilata ◽  
Doris Oliva ◽  
Maritza Sepúlveda
Keyword(s):  
Prey Size ◽  
South American ◽  
Southern Chile ◽  
Otaria Flavescens ◽  
Sea Lions ◽  
Farmed Salmon ◽  
South American Sea Lion ◽  
Autumn And Winter ◽  
Strong Suspicion

Abstract Vilata, J., Oliva, D., and Sepúlveda, M. 2010. The predation of farmed salmon by South American sea lions (Otaria flavescens) in southern Chile. – ICES Journal of Marine Science, 67: 475–482. The South American sea lion Otaria flavescens is abundant off southern Chile. Because Chilean salmon farming has experienced an explosive growth in the past two decades, interactions between O. flavescens and this industry have increased. Fieldwork, including in situ behavioural observations, was carried out at three salmon farms off southern Chile from May to July 2008. The aim was to analyse possible patterns in the interactions and to evaluate whether they were influenced by the endogenous circa-rhythms of the species, prey size, tidal flux, and the use of an acoustic harassment device (AHD). The results showed that the attacks by O. flavescens followed seasonal patterns, with salmon predated more in autumn and winter, and daily patterns, with more interactions at night. In addition, attacks were more frequent on larger salmon, suggesting the existence of a prey-size preference. More sea lions were sighted at the ebb and flow tide peaks, when currents are stronger, suggesting that currents linked to tidal flux might facilitate the access of the sea lions to the farmed salmon. Although the use of AHDs appeared positive at one site, there is a strong suspicion that their efficacy may be site-specific.

ISOLATION OF A STEROID-LIKE SUBSTANCE FROM URINE AND CITROUS FRUITS

1958 ◽  
Vol 36 (1) ◽  
pp. 869-881 ◽  
Author(s):  
Wojciech Nowaczynski ◽  
Thomas Sandor ◽  
Erich Koiw ◽  
R. Norman Jones ◽  
Jacques Genest
Keyword(s):  
Physicochemical Characterization ◽  
Oxidative Degradation ◽  
Physicochemical Characteristics ◽  
Fruit Juices ◽  
Free Form ◽  
Elementary Analysis ◽  
Males And Females ◽  
Normal Males ◽  
Partial Chemical

The isolation and the partial chemical and physicochemical characterization of a chloroform-soluble substance obtained from human urine and citrous fruit juices are presented. The urinary compound, designated as compound III, is present mostly as a conjugate hydrolyzed by animal β-glucuronidase whereas it is in free form in fruit juices. It is present in the urine of normal males and females and in a number of pathological conditions. Its urinary excretion is significantly increased as a result of diets rich in potassium (250 meq./day). In various paper chromatographic systems, the compound has a mobility similar to that of aldosterone. Detailed study of its chemical and physicochemical characteristics, including oxidative degradation and infrared and elementary analysis, suggests a steroidal or sesquiterpinoidal structure. However, at the present time, the data obtained do not permit the final elucidation of the chemical formula of compound III.

scholarly journals DDRT-PCR approaches applied for preeminent results in the isolation of DETs from fish brain tissues

2015 ◽  
Vol 75 (1) ◽  
pp. 224-228
Author(s):  
FA. Alves-Costa ◽  
AP. Wasko
Keyword(s):  
Fish Species ◽  
Tandem Repeats ◽  
Variable Number ◽  
Differentially Expressed ◽  
South American ◽  
Adult Males ◽  
South American Species ◽  
Commercial Species ◽  
Pcr Method ◽  
Males And Females

Differential Display (DD) is a technique widely used in studies of differential expression. Most of these analyses, especially those involving fish species, are restricted to species from North America and Europe or to commercial species, as salmonids. Studies related to South American fish species are underexplored. Thus, the present work aimed to describe DD technique modifications in order to improve outcomes related to the isolation of DETs (Differentially Expressed Transcripts), using Leporinus macrocephalus, a large commercially exploited South American species, as a fish design. Different DDRT-PCR approaches were applied to brain samples and the products of the reactions were analyzed on 6% polyacrylamide gels stained with 0.17% Silver Nitrate (AgNO3). The use of PCR reactions under high stringency conditions and longer oligonucleotides based on VNTR (Variable Number of Tandem Repeats) core sequences led to better results when compared to low stringency PCR conditions and the use of decamer oligonucleotides. The improved approach led to the isolation of differentially expressed transcripts on adult males and females of L. macrocephalus. This study indicates that some modifications on the DDRT-PCR method can ensure isolation of DETs from different fish tissues and the development of robust data related to this approach.

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