Hemisorubim platyrhynchos: A More Manageable Shovelnose Catfish. Author: Seth Gibson. GIBS Photographer: Aaron Norman. Monster cats can reach several . Braz J Biol. Nov;64(4) Epub Mar 2. Age and growth of the porthole shovelnose catfish (Hemisorubim platyrhynchos) in the Pantanal. Hemisorubim platyrhynchos is a medium- to large-sized pimelodid catfish distributed along several river basins of the Neotropical Region.

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The extensive exploitation of its populations due to overfishing could affect its genetic variability, which is still poorly known. Among these, otoliths, vertebrae, and fin-spines are the structures that have produced the best results Fenerich et al. In some cases, sections revealed grooves crossing the rings. The fish, which came from commercial and experimental fisheries, were all caught with hook and line.

Porthole shovelnose catfish

Slow-growing platyrhyncyos may reach this size only when they are older 3 or more rings. The chromosomes were classified according to their arm ratios as metacentrics msubmetacentrics smsubtelocentrics stand acrocentrics a Levan et al.

Idade e crescimento do jurupoca Hemisorubim platyrhynchos platyrhyynchos Pantanal. The results suggest that fork length is a good predictor of age for individuals of this species. Additional information about the study area is given in Penha and Penha et al.

The objective of the present study was to describe the karyotypic structure of specimens from three populations of Hemisorubim platyrhynchos aiming to characterize andcompare the obtained results with the available cytogenetic data on this and other related species.


During the period of legally prohibited fishing between November and February44 additional specimens were collected for research purposes. Received Feb 21; Accepted Mar However, it should be noted that it was fairly difficult to identify the rings on the edge of the spine in individuals with more than five rings. To circumvent the problem created by the reabsorption of the first growth ring Casselman,an ANOVA was performed.

The meat of H. Geneticand Molecular Research 4 4: Journal List Comp Cytogenet platyrhyncohs. The estimated growth parameters indicate that the species presents a relatively slow platyrhymchos rate. Brazilian Journal of Biology 64 4: In this work, Hemisorubim platyrhynchos from three isolated populations were cytogenetically analyzed.

Human uses

The relatively low amount of heterochromatin in chromosomes of Hemisorubim platyrhynchos andin other species of hejisorubim Pimelodidae catfishes suggests that this may be a characteristic of this family.

Services on Demand Journal. Of these genera, Hemisorubim is most closely related to Pseudoplatystoma. Although few studies compare the age determined by various structures of platgrhynchos same sample, preliminary data indicate that age underestimations tend to result when based on pectoral fin-spines in comparison with those based on dorsal spines Layher, and vertebrae Clay, Porthole shovelnose catfish Scientific classification Kingdom: Hemisorubim platyrhynchosPimelodidae, Cytogenetics.

Check date values in: Pimelodidaewith an uncommon large Y chromosome. Suggestion of a Cytotaxonomical Classification. Nucleolus organizer regions Ag-NORs were revealed by the silver-staining method Howell and Black and C-banding was performed according to Sumner Fisheries Management and Ecology However, first-year growth is rapid. Pimelodidaean endangered species from South American rivers.


Age and growth of the porthole shovelnose catfish (Hemisorubim platyrhynchos) in the Pantanal

Journal du Conseil Most studies undertaken so far have founded evidence of ring formation during the dry season Fenerich et platyrhynchso. The Alu I restriction enzyme shows bands that resemble C-banding, principally on the biarmed chromosome, producing a reverse pattern Fig.

Because the confidence intervals overlapped, they were considered statistically the same. This fact was also evidenced when using other banding techniques, such as RE Alu Iand indicates that this pair constitutes a species-specific cytogenetic marker.

Even so, indirect evidence suggests that the pectoral fin-spines of H. The sample used in platyrhychos study included individuals with FL varying from 26 to 64 cm. It feeds on benthic organisms and fish Froese and Pauly The mean length reached in the cohort’s first year of life, shown in column FL 1 of Table 1decreased with the age of the cohort from which it was estimated, the only exception being the most recent cohort.

Hemisorubim platyrhynchos Valenciennes Individual life span was estimated at The mentionedchromosome could be considered a species-specific cytogenetic marker, since it has platyrhjnchos been reported in other species of this group heemisorubim fish.