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2. Somatic pairing, endomitosis and chromosome aberrations in snakes (Viperidae and Colubridae)

Author

Beçak Maria Luiza, Beçak Willy, and Pereira Alexandre

Subjects
snakes, somatic pairing, chromosome positioning, endomitosis, diplochromosomes, Science
Abstract

The positioning of macrochromosomes of Bothrops jararaca and Bothrops insularis (Viperidae) was studied in undistorted radial metaphases of uncultured cells (spermatogonia and oogonia) not subjected to spindle inhibitors. Colchicinized metaphases from uncultured (spleen and intestine) and cultured tissues (blood) were also analyzed. We report two antagonic non-random chromosome arrangements in untreated premeiotic cells: the parallel configuration with homologue chromosomes associated side by side in the metaphase plate and the antiparallel configuration having homologue chromosomes with antipolar distribution in the metaphase ring. The antiparallel aspect also appeared in colchicinized cells. The spatial chromosome arrangement in both configurations is groupal size-dependent and maintained through meiosis. We also describe, in untreated gonia cells, endomitosis followed by reductional mitosis which restores the diploid number. In B. jararaca males we observed that some gonad regions present changes in the meiotic mechanism. In this case, endoreduplicated cells segregate the diplochromosomes to opposite poles forming directly endoreduplicated second metaphases of meiosis with the suppression of first meiosis. By a successive division, these cells form nuclei with one set of chromosomes. Chromosome doubling in oogonia is known in hybrid species and in parthenogenetic salamanders and lizards. This species also presented chromosome rearrangements leading to aneuploidies in mitosis and meiosis. It is suggested that somatic pairing, endomitosis, meiotic alterations, and chromosomal aberrations can be correlated processes. Similar aspects of nuclei configurations, endomitosis and reductional mitosis were found in other Viperidae and Colubridae species.

Published
2003

7. Passeriformes

Author

Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, Beçak, Willy, Chen, T. R., Shoffner, Robert N., Benirschke, Kurt, editor, Hsu, T. C., editor, Beçak, Maria Luiza, editor, Beçak, Willy, editor, Chen, T. R., editor, and Shoffner, Robert N., editor

Published
1975
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8. Squamata

Author

Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, Beçak, Willy, Chen, T. R., Shoffner, Robert N., Benirschke, Kurt, editor, Hsu, T. C., editor, Beçak, Maria Luiza, editor, Beçak, Willy, editor, Chen, T. R., editor, and Shoffner, Robert N., editor

Published
1975
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9. Ciconiiformes

Author

Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, Beçak, Willy, Chen, T. R., Shoffner, Robert N., Benirschke, Kurt, editor, Hsu, T. C., editor, Beçak, Maria Luiza, editor, Beçak, Willy, editor, Chen, T. R., editor, and Shoffner, Robert N., editor

Published
1975
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10. Anseriformes

Author

Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, Beçak, Willy, Chen, T. R., Shoffner, Robert N., Benirschke, Kurt, editor, Hsu, T. C., editor, Beçak, Maria Luiza, editor, Beçak, Willy, editor, Chen, T. R., editor, and Shoffner, Robert N., editor

Published
1975
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11. Rajiformes

Author

Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, Beçak, Willy, Chen, T. R., Shoffner, Robert N., Benirschke, Kurt, editor, Hsu, T. C., editor, Beçak, Maria Luiza, editor, Beçak, Willy, editor, Chen, T. R., editor, and Shoffner, Robert N., editor

Published
1975
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12. Speciation Routes of Anurans

Author

Beçak, Maria Luiza

Subjects
Science / Life Sciences / Zoology / Ethology (Animal Behavior)
Abstract

Genome duplication was long been reported by our laboratory in Brazilian anurans belonging to the Leptodactylidae and Hylidae families. Thanks to other investigators, several polyploid species with related diploid forms were also found in diverse regions of South America, Africa and Australia. Our cytogenetic, enzymatic and molecular experiments performed in the Brazilian polyploids showed a higher level of variability resulting from tetrasomic gene expression according to the binomial equation (p + q)4. These results were supported by the classical Ohno’s theory of vertebrate evolution via genome duplication. Later, we suggested that the epigenetic mutations could have a role in the expansion of the tetraploid animals exploring different regions. Here, we provide an overview of the data on polyploid anurans in light of the speciation process. Some biogeographic events of Mesozoic and Cenozoic Eras probably related to anurans evolution were also focused.

Published
2018

13. Lophortyx californica : California quail

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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14. Zenaidura macroura : Mourning dove

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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15. Meleagris gallopavo : Turkey

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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16. Streptopelia risoria

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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17. Numida meleagris : Guinea fowl

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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18. Phasianus colchicus : Chinese ringneck pheasant

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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19. Columba livia domestica : Common pigeon

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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20. Lophura swinhoei : Swinhoe’s pheasant

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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21. Coturnix coturnix japonica : Japanese quail

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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22. Gallus domesticus : Domestic fowl

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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23. Caiman crocodilus Linnaeus : South American alligator, jacaré

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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24. Bothrops jararacussu Lacerda : Jararacuçu

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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25. Chrysolophus pictus : Golden pheasant

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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26. Mitu mitu : Razor-billed curassow

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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28. Tomodon dorsatus Duméril et Bibron Corre campo

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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29. Bothrops moojeni Hoge Moojen’s fer de lance, caicaca

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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30. Xenodon merremii Wagler : Merrem’s xenodon, Boipeva

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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31. Bothrops jararaca Wied : Jararaca

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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33. Thamnodynastes strigatus Günther : Thamnodynastes

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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34. Chironius bicarinatus Wied : Cipo snake, Cobra cipó

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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35. Boa constrictor amarali Stull : Boa constrictor, Jibóia

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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36. Eunectes murinus Linnaeus : Anaconda, Sucuri

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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37. Epicrates cenchria crassus Cope : Rainbow boa, Salamanta

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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38. Bufo americanus Holbrook : American toad

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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39. Amphisbaena alba Linnaeus

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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40. Anolis carolinensis Cuvier

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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41. Rana dalmatina Bonaparte : Agile frog

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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42. Rana pipiens pipiens Schreber : Northern leopard frog

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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43. Rana esculenta Linnaeus : Water frog

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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44. Rana clamitans Latreille : Green frog

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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45. Xenopus laevis Daudin : African clawed frog or Platanna

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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46. Scaphiopus holbrooki Harlan : Eastern spadefoot toad

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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47. Rana arvalis Nilsson : Moor frog

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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48. Ceratophrys dorsata Wied : Horned frog

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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49. Leptodactylus ocellatus Linnaeus : Ocellated frog

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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50. Bufo marinus Linnaeus : Giant, or marine, toad

Author

Beçak, Maria Luiza, Beçak, Willy, Roberts, Franklin L., Shoffner, Robert N., Volpe, E. Peter, Benirschke, Kurt, Hsu, T. C., Beçak, Maria Luiza, editor, Beçak, Willy, editor, Roberts, Franklin L., editor, Shoffner, Robert N., editor, Volpe, E. Peter, editor, Benirschke, Kurt, editor, and Hsu, T. C., editor

Published
1971
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